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Silver Based Materials

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Pure silver (also called fine silver) exhibits the highest electrical and thermal conductivity of all metals. It is also resistant against oxidation. Major disadvantages are its low mechanical wear resistance, the low softening temperature, and especially its strong affinity to sulfur and sulfur compounds. In the presence of sulfur and sulfur containing compounds brownish to black silver sulfide layer are formed on its surface. These can cause increased contact resistance or even total failure of a switching device if they are not mechanically, electrically, or thermally destroyed. Other weaknesses of silver contacts are the tendency to weld under the influence of over-currents and the low resistance against material transfer when switching DC loads. In humid environments and under the influence of an electrical field silver can creep (silver migration) and cause electrical shorting between adjacent current paths.

<xr id="tab:Overview_of_the_Most_Widely_Used_Silver_Grades"/> shows the typically available quality grades of silver. In certain economic areas, i.e. China, there are additional grades with varying amounts of impurities available on the market. In powder form silver is used for a wide variety of silver based composite contact materials. Different manufacturing processes result in different grades of Ag powder as shown in <xr id="tab:Quality_Criteria_of_Differently_Manufactured_Silver_Powders"/>. ~~additional~~ Additional properties of silver powders and their usage are described in ~~chapter~~ [[ Precious Metal Powders and Preparations#Precious_Metal_Powders|Precious Metal Powders ]] und [[Precious_Metal_Powders_and_Preparations|Table Different Types of Silver Powders.]] Semi-finished silver materials can easily be warm or cold formed and can be clad to the usual base materials(<xr id="fig:Strain hardening of Ag bei cold working"/> and <xr id="fig:Softening of Ag after annealing after different degrees"/>). For attachment of silver to contact carriermaterials welding of wire or profile cut-offs and brazing are most widely applied. Besides these mechanical processes such as wire insertion (wire staking) and the riveting (staking) of solid or composite contact rivets are used in the manufacture of contact components.

Contacts made from fine silver are applied in various electrical switching devices such as relays, pushbuttons, appliance and control switches for

currents < 2 A ''(<xr id="tab:Application Examples and Forms of Supply for Silver and Silver Alloys"/>). Electroplated silver coatings are widely used to reduce the contact resistance and improve the brazing behavior of other contact materials and components.

~~'''Table 2.11: Overview of the Most Widely Used Silver Grades'''~~

<table border="1" cellspacing="0" style="border-collapse:collapse"><tr><td>Designation</td><td>Composition minimum Ag [wt%]</td><td>Impurities[ppm]</td><td>Notes on Usage</td></tr><tr><td>SpectroscopicallyPure Ag</td><td>99.999</td><td>Cu < 3Zn < 1Si < 1Ca < 2Fe < 1Mg < 1Cd < 1</td><td>Sheets, strips, rods, wires for electronic applications</td></tr><tr><td>High Purity Ag, oxygen-free</td><td>99.995</td><td>Cu < 30Zn < 2Si < 5Ca < 10Fe < 3Mg < 5Cd < 3</td><td>Ingots, bars, granulate for alloyingpurposes</td></tr></table>

<figtable id="tab:Overview_of_the_Most_Widely_Used_Silver_Grades"><caption>'''Overview of ~~Differently Manufactured~~ the Most Widely Used Silver ~~Powders~~Grades'''</caption><table class="twocolortable"><tr><th>Designation</th><th>Composition minimum Ag [wt%]</th><th>Impurities[ppm]</th><th>Notes on Usage</th></tr><tr><td>SpectroscopicallyPure Ag</td><td>99.999</td><td>Cu < 3Zn < 1Si < 1Ca < 2Fe < 1Mg < 1Cd < 1</td><td>Sheets, strips, rods, wires for electronic applications</td></tr><tr><td>High Purity Ag, oxygen-free</td><td>99.995</td><td>Cu < 30Zn < 2Si < 5Ca < 10Fe < 3Mg < 5Cd < 3</td><td>Ingots, bars, granulate for alloying purposes</td></tr></table></figtable>

~~Fig. 2.45: Strain hardening of Ag 99.95 by cold working~~

~~[[File:Strain hardening of Ag bei cold working.jpg|right|thumb|Strain hardening of Ag 99.95 bei cold working]]~~

~~Fig~~<figtable id="tab:Quality_Criteria_of_Differently_Manufactured_Silver_Powders"><caption>'''Quality Criteria of Differently Manufactured Silver Powders'''</caption> {| class="twocolortable" style="text-align: left; font-size: 12px"|-!colspan="2" |Impurities !Ag-Chem.46*!Ag-ES**!Ag-V***|-|Cu |ppm|< 100|< 300|< 300|-|Fe |ppm|< 50|< 100|< 100|-|Ni |ppm|< 50|< 50|< 50|-|Cd |ppm|||< 50|-|Zn |ppm|||< 10|-|Na + K + Mg + Ca |ppm|< 80|< 50|< 50|-|Ag CI |ppm|< 500|< 500|< 500|-|NO3 |ppm|< 40|< 40||-|Nh4CI |ppm|< 30|< 30||-!colspan="5" |Particle Size Distribution (screen analysis)|-|> 100 μm |%|0|0|0|-|< 100 bis > 63 μm |%|< 5|< 5|< 15|-|< 36 μm |%|< 80|< 90|< 75|-|Apparent Density |g/cm3|1.0 - 1.6|1.0 - 1.5|3 - 4|-|Tap Density |ml/100g|40 - 50|40 - 50|15 - 25|-!colspan="5" |Press/Sintering Behavior|-|Press Density |g/cm3|5.6 - 6.5|5.6 - 6.3|6.5 - 8.5|-|Sinter Density |g/cm3|> 9|> 9.3|> 8|-|Volume Shrinkage |%|> 34|> 35|> 0|-|Annealing Loss|%|< 2|< 0.1|< 0.1|}</figtable> <nowiki>*</nowiki> Manufactured by chemical precipitation <nowiki>**</nowiki> Manufactured by electrolytic deposition <nowiki>***</nowiki> Manufactured by atomizing of a melt <div class="multiple-images"> <figure id="fig:Strain hardening of Ag bei cold working">[[File: ~~Softening~~ Strain hardening of Ag bei cold working.jpg|left|thumb|<caption>Strain hardening of Ag 99.95 - cold working</caption>]]</figure> <figure id="fig:Softening of Ag after annealing ~~for 1 hr~~ after different degrees ~~of strain hardening~~">[[File:Softening of Ag after annealing after different degrees.jpg|~~right~~left|thumb|<caption>Softening of Ag 99.95 after annealing for 1 hr after different degrees of strain hardening</caption>]]</figure></div><div class="clear"></div>

===Silver Alloys===

To improve the physical and contact properties of fine silver , melt-metallurgical produced silver alloys are used ''(<xr id="tab:Physical Properties of Silver and Silver Alloys"/>). By adding metal components , the mechanical properties such as hardness and tensile strength as well as typical contact properties such as erosion resistance, and resistance against material transfer in DC circuits are increased ''(<xr id="tab:Mechanical Properties of Silver and Silver Alloys"/>). On the other hand however, other properties such as electrical conductivity and chemical corrosion resistance can be negatively impacted by alloying ''(~~Figs~~<xr id="fig:Influence of 1 10 atom of different alloying metals"/> and <xr id="fig:Electrical resistivity p of AgCu alloys"/>). <figtable id="tab:Physical Properties of Silver and Silver Alloys"><caption>'''Physical Properties of Silver and Silver Alloys'''</caption> {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Silver Content [wt%]!Density [g/cm3]!Melting Point or Range [°C]!Electrical Resistivity [μΩ·cm]!Electrical Conductivity [MS/m]!Thermal Conductivity [W/mK]!Temp. Coefficient of the Electr.Resistance [10-3/K]!Modulus of Elasticity [GPa]|-|Ag|99.95|10.5|961|1.67|60|419|4.1|80|-|AgNi0.15|99.85|10.5|960|1.72|58|414|4.0|82|-|AgCu3|97|10.4|900 - 938|1.92|52|385|3.2|85|-|AgCu5|95|10.4|910|1.96|51|380|3.0|85|-|AgCu10|90|10.3|870|2.0|50|335|2.8|85|-|AgCu28|72|10.0|779|2.08|48|325|2.7|92|-|Ag98CuNi ARGODUR 27|98|10.4|940|1.92|52|385|3.5|85|-|AgCu24.5Ni0.5|75|10.0|805|2.20|45|330|2.7|92|-|Ag99.5NiMg ARGODUR 32 Not heat treated|99.5|10.5|960|2.32|43|293|2.3|80|-|ARGODUR 32 Heat treated|99.5|10.5|960|2.32|43|293|2.1|80|}</figtable> <div class="multiple-images"> <figure id="fig:Influence of 1 10 atom of different alloying metals">[[File:Influence of 1 10 atom of different alloying metals.jpg|left|thumb|<caption>Influence of 1-10 atom% of different alloying metals on the electrical resistivity of silver</caption>]]</figure> <figure id="fig:Electrical resistivity p of AgCu alloys">[[File:Electrical resistivity p of AgCu alloys.jpg|left|thumb|<caption>Electrical resistivity p of AgCu alloys with 0-20 weight% Cu in the soft annealed and tempered stage a) Annealed and quenched b) Tempered at 280°C</caption>]]</figure></div><div class="clear"></div> <figtable id="tab:Mechanical Properties of Silver and Silver Alloys"><caption>'''Mechanical Properties of Silver and Silver Alloys'''</caption><table class="twocolortable"><tr><th>Material</th><th>HardnessCondition</th><th>Tensile StrengthRm [MPa]</th><th>Elongation A [%] min.</th><th>Vickers HardnessHV 10</th></tr><tr><td>Ag</td><td>R 200R 250R 300R 360</td><td>200 - 250250 - 300300 - 360> 360</td><td>30832</td><td>30608090</td></tr><tr><td>AgNi0.15</td><td>R 220R 270R 320R 360</td><td>220 - 270270 - 320320 - 360> 360</td><td>25621</td><td>407085100</td></tr><tr><td>AgCu3</td><td>R 250R 330R 400R 470</td><td>250 - 330330 - 400400 - 470> 470</td><td>25421</td><td>4590115120</td></tr><tr><td>AgCu5</td><td>R 270R 350R 460R 550</td><td>270 - 350350 - 460460 - 550> 550</td><td>20421</td><td>5590115135</td></tr><tr><td>AgCu10</td><td>R 280R 370R 470R 570</td><td>280 - 370370 - 470470 - 570> 570</td><td>15321</td><td>6095130150</td></tr><tr><td>AgCu28</td><td>R 300R 380R 500R 650</td><td>300 - 380380 - 500500 - 650> 650</td><td>10321</td><td>90120140160</td></tr><tr><td>Ag98CuNiARGODUR 27</td><td>R 250R 310R 400R 450</td><td>250 - 310310 - 400400 - 450> 450</td><td>20521</td><td>5085110120</td></tr><tr><td>AgCu24,5Ni0,5</td><td>R 300R 600</td><td>300 - 380> 600</td><td>101</td><td>105180</td></tr><tr><td>Ag99,5NiMgARGODUR 32Not heat treated</td><td>R 220R 260R 310R 360</td><td>220260310360</td><td>25521</td><td>407085100</td></tr><tr><td>ARGODUR 32 Heat treated</td><td>R 400</td><td>400</td><td>2</td><td>130-170</td></tr></table></figtable>

~~Fig. 2.47: Influence of 1-10 atom% of different alloying metals on the electrical resistivity of silver~~

~~[[File:Influence of 1 10 atom of different alloying metals.jpg|right|thumb|Influence of 1-10 atom% of different alloying metals on the electrical resistivity of silver]]~~

~~Fig. 2.48:~~

[[File:Electrical resistivity p of AgCu alloys.jpg|right|thumb|Electrical resistivity p of AgCu alloys with 0-20 weight% Cu in the soft annealed and tempered stage a) Annealed and quenched b) Tempered at 280°C]]

====Fine-Grain Silver====

Fine-Grain ~~Silver (ARGODUR-Spezial)~~ silver is defined as a silver alloy with an addition of 0.15 wt% of ~~Nickel~~nickel. Silver and nickel are not soluble in each other in solid form. In liquid silver , only a small amount of nickel is soluble as the phase diagram ''illustrates (<xr id="fig:Phase diagram of silver nickel"/>). During solidification of the melt , this nickel addition gets finely dispersed in the silver matrix and eliminates the pronounce coarse grain growth after prolonged influence of elevated temperatures ''(~~Figs~~<xr id="fig:Coarse grain micro structure of Ag"/> and <xr id="fig:Fine grain microstructure of AgNiO"/>). <div class="multiple-images">

~~Fig. 2.49~~<figure id="fig: Coarse grain micro structure of Ag ~~99.97 after 80% cold working and 1 hr annealing at 600°C~~">[[File:Coarse grain micro structure of Ag.jpg|~~right~~left|thumb|<caption>Coarse grain micro structure of Ag 99.97 after 80% cold working and 1 hr annealing at 600°C</caption>]]</figure>

~~Fig. 2.50~~<figure id="fig: Fine grain microstructure of ~~AgNi0.15 after 80% cold working and 1 hr annealing at 600°C~~AgNiO">[[File:Fine grain microstructure of AgNiO.jpg|~~right~~left|thumb|<caption>Fine grain microstructure of AgNi0.15 after 80% cold working and 1 hr annealing at 600°C</caption>]]</figure>

<figure id="fig:Phase diagram of silver nickel">[[File:Phase diagram of silver nickel.jpg|left|thumb|<caption>Phase diagram of silver nickel</caption>]]</figure></div><div class="clear"></div> Fine-~~grain~~ Grain silver has almost the same chemical corrosion resistance as fine silver. Compared to pure silver , it exhibits a slightly increased hardness andtensile strength ''(<xr id="tab:Mechanical Properties of Silver and Silver Alloys"/>). The electrical conductivity is just slightly decreased by this low nickel addition. Because of its significantly improved contact properties , fine grain silver has replaced pure silver in many applications.

====Hard-Silver Alloys====

Using copper as an alloying component increases the mechanical stability of silver significantly(<xr id="fig:Strain hardening of AgCu3 by cold working"/>, <xr id="fig:Softening of AgCu3 after annealing"/> and <xr id="fig:Strain hardening of AgCu5 by cold working"/>). The most important among the binary AgCu alloys is that of AgCu3, ~~known~~ in europe also ~~under the name of~~ known as hard-silver. This material still has a chemical corrosion resistance close to that of fine silver. In comparison to pure silver and fine-grain silver , AgCu3 exhibits increased mechanical strength as well as higher arc erosion resistance and mechanical wear resistance ~~''(Table 2.14)''~~.

Increasing the Cu content further also increases the mechanical strength of AgCu alloys and improves arc erosion resistance and resistance against material transfer while ~~at the same time however~~ simultaneously the tendency to oxide formation becomes detrimental. This causes - during switching under arcing conditions - an increase in contact resistance with rising numbers of operation. In special applications , where highest mechanical strength is recommended and a reduced chemical resistance can be tolerated, the eutectic AgCu alloy with 28 wt% of copper ''is used (<xr id="fig:Phase diagram of silver copper"/>). AgCu10 , also known as coin silver , has been replaced in many applications by composite silver-based materials while sterling silver (AgCu7.5) has never extended its important usage from decorative table wear and jewelry to industrial applications in electrical contacts.

Besides these binary alloys, ternary AgCuNi alloys are used in electrical contact applications. From this group , the material ARGODUR 27, an alloy of 98 wt% Ag with a 2 wt% Cu and nickel addition has found practical importance close to that of AgCu3. This material is characterized by high resistance to oxidation and low tendency to re-crystallization during exposure to high temperatures. Besides high mechanical stability this AgCuNi alloy also exhibits a strong resistance against arc erosion. Because of its high resistance against material transfer , the alloy AgCu24.5Ni0.5 has been used in the automotive industry for an extended time in the North American market. Caused by miniaturization and the related reduction in available contact forces in relays and switches , this material has been replaced widely because of its tendency to oxide formation.

The attachment methods used for the hard silver materials are mostly close to those applied for fine silver and fine grain silver.

Hard-silver alloys are widely used for switching applications in the information and energy technology for currents up to 10 A, in special cases also for higher current ranges ''(<xr id="tab:Application Examples and Forms of Supply for Silver and Silver Alloys"/>). Dispersion hardened alloys of silver with 0.5 wt% MgO and NiO (ARGODUR 32) are produced by internal oxidation. While the melt-metallurgical alloy is easy to cold-work and form, the material becomes very hard and brittle after dispersion hardening. Compared to fine silver and hard-silver, this material has a greatly improved temperature stability and can be exposed to brazing temperatures up to 800°C without decreasing its hardness and tensile strength.Because of these mechanical properties and its high electrical conductivity ARGODUR 32 is mainly used in the form of contact springs that are exposed to high thermal and mechanical stresses in relays and contactors for aeronautic applications. <div class="multiple-images"> <figure id="fig:Phase diagram of silver copper"> [[File:Phase diagram of silver copper.jpg|left|thumb|<caption>Phase diagram of silver-copper</caption>]]</figure> <figure id="fig:Strain hardening of AgCu3 by cold working"> [[File:Strain hardening of AgCu3 by cold working.jpg|left|thumb|<caption>Strain hardening of AgCu3 by cold working</caption>]]</figure> <figure id="fig:Softening of AgCu3 after annealing"> [[File:Softening of AgCu3 after annealing.jpg|left|thumb|<caption>Softening of AgCu3 after annealing for 1 hr after 80% cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgCu5 by cold working"> [[File:Strain hardening of AgCu5 by cold working.jpg|left|thumb|<caption>Strain hardening of AgCu5 by cold working</caption>]]</figure> <figure id="fig:Softening of AgCu5 after annealing"> [[File:Softening of AgCu5 after annealing.jpg|left|thumb|<caption>Softening of AgCu5 after annealing for 1 hr after 80% cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgCu 10 by cold working"> [[File:Strain hardening of AgCu 10 by cold working.jpg|left|thumb|<caption>Strain hardening of AgCu 10 by cold working</caption>]]</figure> <figure id="fig:Softening of AgCu10 after annealing"> [[File:Softening of AgCu10 after annealing.jpg|left|thumb|<caption>Softening of AgCu10 after annealing for 1 hr after 80% cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgCu28 by cold working"> [[File:Strain hardening of AgCu28 by cold working.jpg|left|thumb|<caption>Strain hardening of AgCu28 by cold working</caption>]]</figure> <figure id="fig:Softening of AgCu28 after annealing"> [[File:Softening of AgCu28 after annealing.jpg|left|thumb|<caption>Softening of AgCu28 after annealing for 1 hr after 80% cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgNi0.15 by cold working"> [[File:Strain hardening of AgNiO15 by cold working.jpg|left|thumb|<caption>Strain hardening of AgNiO15 by cold working</caption>]]</figure> <figure id="fig:Softening of AgNi0.15 after annealing"> [[File:Softening of AgNiO15 after annealing.jpg|left|thumb|<caption>Softening of AgNiO15 after annealing</caption>]]</figure> <figure id="fig:Strain hardening of ARGODUR 27"> [[File:Strain hardening of ARGODUR 27.jpg|left|thumb|<caption>Strain hardening of AgCu1.8Ni0.2 (ARGODUR 27) by cold working</caption>]]</figure>

~~Dispersion hardened alloys~~ <figure id="fig:Softening of ~~silver with 0.5 wt% MgO and NiO (~~ARGODUR ~~32) are produced by internal oxidation. While the melt-metallurgical alloy is easy to cold-work and form the material becomes very hard and brittle~~ 27 after dispersion hardening. Compared to fine silver and hard-silver this material has a greatly improved temperature stability and can be exposed to brazing temperatures up to 800°C without decreasing its hardness and tensile strength.annealing"> ~~Because~~ [[File:Softening of ~~these mechanical properties and its high electrical conductivity ???~~ ARGODUR ~~32 is mainly used in the form~~ 27 after annealing.jpg|left|thumb|<caption>Softening of ~~contact springs that are exposed to high thermal and mechanical stresses in relays, and contactors~~ AgCu1.8Ni0.2 (ARGODUR 27) after annealing for ~~aeronautic applications.~~1 hr after 80% cold working</caption>]]</figure></div><div class="clear"></div>

~~'''Table 2.13: Physical Properties of Silver and Silver Alloys'''~~

~~Fig. 2.51: Phase diagram of silver-nickel~~

~~[[File:Phase diagram of silver nickel.jpg|right|thumb|Phase diagram of silver nickel]]~~

~~Fig. 2.52~~<figtable id="tab: ~~Phase diagram~~ Contact and Switching Properties of ~~silver~~Silver and Silver Alloys"><caption>'''<!-~~copper[[File:Phase diagram of silver copper.jpg|right|thumb|Phase diagram of silver~~-~~copper]]Fig.~~ Table 2.5315: ~~Phase diagram of silver~~-~~cadmium[[File:Phase diagram of silver cadmium.jpg|right|thumb|Phase diagram of silver~~-~~cadmium]]Fig. 2.54: Strain hardening of AgCu3 by cold working[[File:Strain hardening of AgCu3 by cold working.jpg|right|thumb|Strain hardening~~ >Contact and Switching Properties of ~~AgCu3 by cold working]]~~Silver and Silver Alloys'''</caption>

~~'''Table 2.14: Mechanical Properties of Silver and Silver Alloys'''<table border~~{| class="~~1" cellspacing="0~~twocolortable" style="~~border~~text-~~collapse~~align:collapse"><tr><td>Material/DODUCO-Designation</td><td>HardnessCondition</td><td>Tensile StrengthRm [MPa]</td><td>Elongation A [%] min.</td><td>Vickers HardnessHV 10</td></tr><tr><td>Ag</td><td>R 200R 250R 300R 360</td><td>200 - 250250 - 300300 - 360&gtleft; 360</td><td>30832</td><td>30608090</td></tr><tr><td>AgNi 0,15ARGODUR Special</td><td>R 220R 270R 320R 360</td><td>220 font- ~~270270~~ |- ~~320320 - 360> 360</td><td>256~~2~~1</td><td>407085100</td></tr><tr><td>AgCu3</td><td>R 250R 330R 400R 470</td><td>250 | Properties|- ~~330~~|Ag 330 - 400400 - 470> 470</td><td>25421</td><td>4590115120</td></tr><tr><td>AgCu5</td><td>R 270R 350R 460R 550</td><td>270 - 350350 - 460460 - 550> 550</td><td>20421</td><td>5590115135</td></tr><tr><td>AgCu10</td><td>R 280R 370R 470R 570</td><td>280 - 370370 - 470470 - 570> 570</td><td>AgNi0.15321</td><td>6095130150</td></tr><tr><td>AgCu28</td><td>R 300R 380R 500R 650</td><td>300 |Highest electrical and thermal conductivity, high affinity to sulfur (sulfide formation), low welding resistance, low contact resistance, very good formability |Oxidation resistant at higher make currents, limited arc erosion resistance, tendency to material transfer in DC circuits, easy to braze and weld to carrier materials|- 380380 - 500500 - 650> 650</td><td>10321</td><td>90120140160</td></tr><tr><td>Ag98CuNiARGODUR 27</td><td>R 250R 310R 400R 450</td><td>250 - 310310 - 400400 - 450> 450</td><td>20521</td><td>5085110120</td></tr><tr><td>AgCu24|Ag Alloys |Increasing contact resistance with increasingCu content,~~5Ni0~~compared to fine Ag higher arc erosion resistance and mechanical strength,5</td><td>R 300R 600</td><td>300 - 380> 600</td><td>101</td><td>105180</td></tr><tr><td>AgCd10</td><td>R 200R 280R 400R 450</td><td>200 - 280280 - 400400 - 450> 450</td><td>15321</td><td>3675100115</td></tr><tr><td>Ag99lower tendency to material transfer|Good formability,5NiMgARGODUR 32Not heat treated</td><td>R 220R 260R 310R 360</td><td>220260310360</td><td>25521</td><td>407085100</td></tr><tr><td>ARGODUR 32 Heat treated</td><td>R 400</td><td>400</td><td>2</td><td>130-170</td></tr>good brazing and welding properties |}</~~tablefigtable>

~~Fig. 2.55: Softening of AgCu3 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of AgCu3 after annealing.jpg|right|thumb|Softening of AgCu3 after annealing for 1 hr after 80% cold working]]~~

~~Fig. 2.56: Strain hardening of AgCu5 by cold working~~

~~[[File:Strain hardening of AgCu5 by cold working.jpg|right|thumb|Strain hardening of AgCu5 by cold working]]~~

~~Fig. 2.57: Softening of AgCu5 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of AgCu5 after annealing.jpg|right|thumb|Softening of AgCu5 after annealing for 1 hr after 80% cold working]]~~

~~Fig. 2.58: Strain hardening of AgCu 10 by cold working~~

~~[[File:Strain hardening of AgCu 10 by cold working.jpg|right|thumb|Strain hardening of AgCu 10 by cold working]]~~

~~Fig. 2.59: Softening of AgCu10 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of AgCu10 after annealing.jpg|right|thumb|Softening of AgCu10 after annealing for 1 hr after 80% cold working]]~~

~~Fig. 2.60: Strain hardening of AgCu28 by cold working~~

~~[[File:Strain hardening of AgCu28 by cold working.jpg|right|thumb|Strain hardening of AgCu28 by cold working]]~~

~~Fig. 2.61: Softening of AgCu28 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of AgCu28 after annealing.jpg|right|thumb|Softening of AgCu28 after annealing for 1 hr after 80% cold working]]~~

~~Fig. 2.62: Strain hardening of AgNi0.15 by cold working~~

~~[[File:Strain hardening of AgNiO15 by cold working.jpg|right|thumb|Strain hardening of AgNiO15 by cold working]]~~

~~Fig. 2.63: Softening of AgNi0.15 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of AgNiO15 after annealing.jpg|right|thumb|Softening of AgNiO15 after annealing]]~~

~~Fig. 2.64: Strain hardening of ARGODUR 27 by cold working~~

~~[[File:Strain hardening of ARGODUR 27.jpg|right|thumb|Strain hardening of ARGODUR 27 by cold working]]~~

~~Fig. 2.65: Softening of ARGODUR 27 after annealing for 1 hr after 80% cold working~~

~~[[File:Softening of ARGODUR 27 after annealing.jpg|right|thumb|Softening of ARGODUR 27 after annealing for 1 hr after 80% cold working]]~~

~~Table 2.15: Contact and Switching Properties of Silver and Silver Alloys~~

<figtable id="tab:Application Examples and Forms of Supply for Silver and Silver Alloys"><caption>'''Application Examples and Forms of Supply for Silver and Silver Alloys'''</caption> {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Application Examples!Form of Supply|-|Ag AgNi0.15 AgCu3 AgNi98NiCu2 ARGODUR 27 AgCu24,5Ni0,5|Relays, Micro switches, Auxiliary current switches, Control circuit devices, Appliance switches, Wiring devices (≤ 20A), Main switches |'''Semi-finished Materials:''' Strips, wires, contact profiles, clad contact strips, toplay profiles, seam- welded strips '''Contact Parts:''' Contact tips, solid and composite rivets, weld buttons; clad, welded and riveted contact parts|-|AgCu5 AgCu10 AgCu28 |Special applications|'''Semi-finished Materials:''' Strips, wires, contact profiles, clad contact strips, seam-welded strips '''Contact parts:''' Contact tips, solid contact rivets, weld buttons; clad, welded and riveted contact parts|-|Ag99.5NiOMgO ARGODUR 32|Miniature relays, aerospace relays and contactors, erosion wire for injection nozzles|Contact springs, contact carrier parts |}</figtable>

====Silver-Palladium Alloys====

The addition of 30 wt% Pd increases the mechanical properties as well as theresistance of silver against the influence of sulfur and sulfur containingcompounds significantly ''(~~Tables~~ <xr id="tab:Physical Properties of Silver-Palladium Alloys"/> and <xr id="tab:Mechanical Properties of Silver-Palladium Alloys"/>).Alloys with 40-60 wt% Pd have an even higher resistance against silver sulfideformation. At these percentage ranges however , the catalytic properties ofpalladium can influence the contact resistance behavior negatively. Theformability also decreases with increasing Pd contents. AgPd alloys are hard, arc erosion resistant, and have a lower tendency towards material transfer under DC loads (<xr id="tab:Contact and Switching Properties of Silver-Palladium Alloys"/>). On the other hand, the electrical conductivity is decreased at higher Pd contents. The ternary alloy AgPd30Cu5 has an even higher hardness, which makes it suitable for use in sliding contact systems. AgPd alloys are mostly used in relays for the switching of medium to higher loads (> 60V, > 2A) as shown in <xr id="tab:Application Examples and Forms of Suppl for Silver-Palladium Alloys"/>. Because of the high palladium price, these formerly solid contacts have been widely replaced by multi-layer designs such as AgNi0.15 or AgNi10 with a thin Au surface layer. A broader field of application for AgPd alloys remains in the wear resistant sliding contact systems. <div class="multiple-images"><figure id="fig:Phase diagram of silver palladium">[[File:Phase diagram of silver palladium.jpg|left|thumb|<caption>Phase diagram of silver-palladium</caption>]]</figure> <figure id="fig:Strain hardening of AgPd30 by cold working">[[File:Strain hardening of AgPd30 by cold working.jpg|left|thumb|<caption>Strain hardening of AgPd30 by cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgPd50 by cold working">[[File:Strain hardening of AgPd50 by cold working.jpg|left|thumb|<caption>Strain hardening of AgPd50 by cold working</caption>]]</figure> <figure id="fig:Strain hardening of AgPd30Cu5 by cold working">[[File:Strain hardening of AgPd30Cu5 by cold working.jpg|left|thumb|<caption>Strain hardening of AgPd30Cu5 by cold working</caption>]]</figure> <figure id="fig:Softening of AgPd30 AgPd50 AgPd30Cu5">[[File:Softening of AgPd30 AgPd50 AgPd30Cu5.jpg|left|thumb|<caption>Softening of AgPd30, AgPd50, and AgPd30Cu5 after annealing of 1 hr after 80% cold working</caption>]]</figure></div><div class="clear"></div>

~~AgPd alloys are hard, arc erosion resistant, and have a lower tendency towards~~

~~material transfer under DC loads ''(Table 2.19)''. On the other hand the electrical~~

~~conductivity is decreased at higher Pd contents. The ternary alloy AgPd30Cu5~~

~~has an even higher hardness which makes it suitable for use in sliding contact~~

~~systems.~~

~~AgPd alloys are mostly used in relays for the switching~~ <figtable id="tab:Physical Properties of ~~medium to higher loads~~(Silver-Palladium Alloys">~~60V, >2A) as shown in Table 2.20. Because of the high palladium price theseformerly solid contacts have been widely replaced by multi-layer designs suchas AgNi0.15 or AgNi10 with a thin Au surface layer. A broader field of applicationfor AgPd alloys remains in the wear resistant sliding contact systems.~~

~~Fig.~~ <caption>''' Physical Properties of ~~silver~~Silver-~~palladium~~Palladium Alloys'''</caption>

~~Fig~~{| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material!Palladium Content [wt%]!Density [g/cm3]!Melting Point or Range [°C]!Electrical Resistivity [μΩ·cm]!Electrical Conductivity [MS/m]!Thermal Conductivity [W/m·K]!Temp. Coefficient of the Electr. Resistance [10-3/K]|-|AgPd30|30|10.9|1155 - 1220|14.7|6.8|60|0.4|-|AgPd40|40|11.1|1225 - 1285|20.8|4.8|46|0.36|-|AgPd50|50|11. 2|1290 - 1340|32.~~67:~~3|3.1|34|0.23|-|AgPd60|60|11.4|1330 - 1385|41.7|2.4|29|0.12|-|AgPd30Cu5|30|10.8|1120 - 1165|15.6|6.4|28|0.37~~Strain hardening~~|}~~of AgPd30 by cold working~~</figtable>

~~Fig. 2.68:~~

~~Strain hardening~~

~~of AgPd50 by cold working~~

~~Fig.~~ <figtable id="tab:Mechanical Properties of Silver-Palladium Alloys"><caption>'''Mechanical Properties of Silver-Palladium Alloys'''</caption>~~Strain hardening~~<table class="twocolortable">of <tr><th>Material</th><th>HardnessCondition</th><th>Tensile StrengthRm[MPa]</th><th>Elongation A[%]min.</th><th>Vickers HardnessHV</th></tr><tr><td>AgPd30</td><td>R 320R 570</td><td>320570</td><td>383</td><td>65145</td></tr><tr><td>AgPd40</td><td>R 350R 630</td><td>350630</td><td>382</td><td>72165</td></tr><tr><td>AgPd50</td><td>R 340R 630</td><td>340630</td><td>352</td><td>78185</td></tr><tr><td>AgPd60</td><td>R 430R 700</td><td>430700</td><td>302</td><td>85195</td></tr><tr><td>AgPd30Cu5</td><td>R 410R 620</td><td>410620</td><td>402</td><td>90190</td></tr></table>~~by cold working~~</figtable>

~~Fig. 2.70:~~

~~Softening of AgPd30, AgPd50,~~

~~and AgPd30Cu5 after annealing of 1 hr~~

~~after 80% cold working~~

<figtable id="tab:Contact and Switching Properties of Silver-Palladium Alloys"><caption>'''Contact and Switching Properties of Silver-Palladium Alloys''</caption>'

~~Table~~ {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !colspan="2~~.18: Mechanical~~ " | Properties ~~of Silver~~|-|AgPd30-60|Corrosion resistant, tendency to Brown Powder formation increases with Pd content, low tendency to material transfer in DC circuits, high ductility |Resistant against Ag2S formation, low contact resistance, increasing hardness with higher Pd content, AgPd30 has highest arc erosion resistance, easy to weld and clad|-~~Palladium Alloys~~|AgPd30Cu5 |High mechanical wear resistance|High Hardness |}</figtable>

~~Table 2.19: Contact and Switching Properties of Silver-Palladium Alloys~~

<figtable id="tab:Application Examples and Forms of Suppl for Silver-Palladium Alloys"><caption>'''Application Examples and Forms of Suppl for Silver-Palladium Alloys'''</caption><table class="twocolortable"><tr><th>Material</th><th>Application Examples</th><th>Form of Supply</th></tr><tr><td>AgPd 30-60</td><td>Switches, relays, push-buttons,connectors, sliding contacts</td><td>'''Semi-finished Materials:'''Wires, micro profiles (weld tapes), cladcontact strips, seam-welded strips'''Contact Parts:'''Solid and composite rivets, weld buttons;clad and welded contact parts, stamped parts</td></tr><tr><td>AgPd30Cu5</td><td>Sliding contacts, slider tracks</td><td>Wire-formed parts, contact springs, solidand clad stamped parts</td></tr></table></figtable>

===Silver Composite Materials===

====Silver-Nickel ~~(SINIDUR)~~ Materials====Since silver and nickel are not soluble in each other in solid form and also show very limited solubility in the liquidphase ~~have only very limited solubility~~ , silver nickel composite materials withhigher Ni contents can only be produced by powder metallurgy. During extrusionof sintered Ag/Ni billets into wires, strips and rods , the Ni particles embedded inthe Ag matrix are stretched and oriented in the microstructure into a pronouncedfiber structure ''(~~Figs~~<xr id="fig:Micro structure of AgNi9010"/> and <xr id="fig:Micro structure of AgNi 8020"/>) The high density produced during hot extrusion, aids the arc erosion resistance of these materials (<xr id="tab:Physical Properties of Silver-Nickel (SINIDUR) Materials"/>). The typical application of Ag/Ni contact materials is in devices for switching currents of up to 100A (<xr id="tab:Application Examples and Forms of Supply for Silver-Nickel (SINIDUR) Materials"/>). In this range, they are significantly more erosion resistant than silver or silver alloys. In addition, they exhibit with nickel contents < 20 wt% a low and over their operational lifetime consistent contact resistance and good arc moving properties. In DC applications Ag/Ni materials exhibit a relatively low tendency of material transfer distributed evenly over the contact surfaces (<xr id="tab:Contact and Switching Properties of Silver-Nickel (SINIDUR) Materials"/>). Typically Ag/Ni materials are usually produced with contents of 10-40 wt% Ni. The most common used materials Ag/Ni 10 and Ag/Ni 20- and also Ag/Ni 15, mostly used in north america-, are easily formable and applied by cladding (<xr id="fig:Strain hardening of AgNi9010 by cold working"/>, <xr id="fig:Softening of AgNi9010 after annealing"/>, <xr id="fig:Strain hardening of AgNi8020"/>,  <xr id="fig:Softening of AgNi8020 after annealing"/>). They can be, without any additional welding aids, economically welded and brazed to the commonly used contact carrier materials.The Ag/Ni materials with nickel contents of 30 and 40 wt% are used in switching devices, requiring a higher arc erosion resistance and where increases in contact resistance can be compensated through higher contact forces. The most important applications for Ag/Ni contact materials are typically in relays, wiring devices, appliance switches, thermostatic controls, auxiliary switches and small contactors with nominal currents > 20A (<xr id="tab:Application Examples and Forms of Supply for Silver-Nickel (SINIDUR) Materials"/>). <figtable id="tab:Physical Properties of Silver-Nickel (SINIDUR)Materials"><caption>'''Physical Properties of Silver-Nickel Materials'''</caption><table class="twocolortable"><tr><th>Material</th><th>Silver Content</th><th>Density</th><th>Melting Point</th><th>ElectricalResistivityp</th><th colspan="2">Electrical Resistivity (soft)</th></tr><tr><th></th><th>[wt%]</th><th>[g/cm3]</th><th>[°C]</th><th>[µΩ·cm]</th><th>[% IACS]</th><th>[MS/m]</th></tr><tr><td>Ag/Ni 90/10</td><td>89 - 91</td><td>10.2 - 10.3</td><td>960</td><td>1.82 - 1.92</td><td>90 - 95</td><td>52 - 55</td></tr><tr><td>Ag/Ni 85/15</td><td>84 - 86</td><td>10.1 - 10.2</td><td>960</td><td>1.89 - 2.0</td><td>86 - 91</td><td>50 - 53</td></tr><tr><td>Ag/Ni 80/20</td><td>79 - 81</td><td>10.0 - 10.1</td><td>960</td><td>1.92 - 2.08</td><td>83 - 90</td><td>48 - 52</td></tr><tr><td>Ag/Ni 70/30</td><td>69 - 71</td><td>9.8</td><td>960</td><td>2.44</td><td>71</td><td>41</td></tr><tr><td>Ag/Ni 60/40</td><td>59 - 61</td><td>9.7</td><td>960</td><td>2.70</td><td>64</td><td>37</td></tr></table></figtable> <figtable id="tab:tab2.22"><caption>'''Mechanical Properties of Silver-Nickel Materials'''</caption>

~~The high density produced during hot extrusion aids the arc erosion resistance~~{| class="twocolortable" style="text-align: left; font-size: 12px"~~of these materials ''~~|-!Material !Hardness Condition!Tensile Strength Rm [Mpa]!Elongation A (~~Tables 2~~soft annealed) [%] min.~~21 and~~ !Vickers Hardness HV 10|-|Ag/Ni 90/10 |soft R 220 R 280 R 340 R 400|< 250 220 - 280 280 - 340 340 - 400 > 400|25 20 3 2~~.22)''. The typical application of~~ 1|< 50 50 - 70 65 - 90 85 - 105 > 100|-|Ag/Ni85/15 ~~contact materials is in devices for switching currents of up to 100A ''(Table~~ |soft R 300 R 350 R 380 R 400|< 275 250 - 300 300 - 350 350 - 400 > 400|20 4 2 2~~.24)''.~~ 1|< 70 70 - 90 85 - 105 100 - 120 > 115|-|Ag/Ni 80/20 ~~In this range they are significantly more erosion resistant than silver or silver~~|soft R 300 R 350 R 400 R 450~~alloys. In addition they exhibit with nickel contents~~ |< 300 300 - 350 350 - 400 400 - 450 > 450|20 ~~wt% a low and over their~~ 4 2 2 1|< 80 80 - 95 90 - 110 100 - 125 > 120|-|Ag/Ni 70/30 |R 330 R 420 R 470 R 530|330 - 420 420 - 470 470 - 530 > 530|8 2 1 1|80 100 115 135~~operational lifetime consistent contact resistance and good arc moving~~|-~~properties. In DC applications~~ |Ag/Ni ~~materials exhibit a relatively low tendency~~60/40 |R 370 R 440 R 500 R 580|370 - 440 440 - 500 500 - 580 > 580~~of material transfer distributed evenly over the contact surfaces ''(Table~~ |6 2~~.23)''.~~ 1 1|90 110 130 150|}</figtable>

~~Typically Ag/Ni (SINIDUR) materials are usually produced with contents of 10-40~~

~~wt% Ni. The most widely used materials SINIDUR 10 and SINIDUR 20- and also~~

~~SINIDUR 15, mostly used in north america-, are easily formable and applied by~~

~~cladding ''(Figs. 2.71-2.74)''. They can be, without any additional welding aids,~~

~~economically welded and brazed to the commonly used contact carrier~~

~~materials.~~

~~The (SINIDUR) materials with nickel contents of 30 and 40 wt% are used in~~

~~switching devices requiring a higher arc erosion resistance and where increases~~

~~in contact resistance can be compensated through higher contact forces.~~

~~The most important applications for~~ <div class="multiple-images"><figure id="fig:Strain hardening of AgNi9010 by cold working">[[File:Strain hardening of AgNi9010 by cold working.jpg|right|thumb|<caption>Strain hardening of Ag/Ni ~~contact materials are typically in~~90/10 by cold working</caption>]]~~relays, wiring devices, appliance switches, thermostatic controls, auxiliaryswitches, and small contactors with nominal currents~~ </figure>~~20A ''(Table 2.24)''.~~

~~Table 2~~<figure id="fig:Softening of AgNi9010 after annealing">[[File:Softening of AgNi9010 after annealing.~~21: Physical Properties~~ jpg|right|thumb|<caption>Softening of ~~Silver-Nickel (SINIDUR) Materials~~Ag/Ni 90/10 after annealing for 1 hr after 80% cold working</caption>]]</figure>

~~Table 2~~<figure id="fig:Strain hardening of AgNi8020">[[File:Strain hardening of AgNi8020.~~22: Mechanical Properties~~ jpg|right|thumb|<caption>Strain hardening of ~~Silver-Nickel (SINIDUR) Materials~~Ag/Ni 80/20 by cold working</caption>]]</figure>

~~Fig. 2.71~~<figure id="fig:Softening of AgNi8020 after annealing">~~Strain hardening~~[[File:Softening of AgNi8020 after annealing.jpg|right|thumb|<caption>Softening of Ag/Ni 9080/~~10 by~~ 20 after annealing for 1 hr after 80% cold working</caption>]]</figure>

~~Fig. 2.72~~<figure id="fig:Micro structure of AgNi9010">~~Softening~~ [[File:Micro structure of AgNi9010.jpg|right|thumb|<caption>Micro structure of Ag/Ni 90/10a) perpendicular to the extrusion direction b) parallel to the extrusion direction</caption>]]~~after annealingfor 1 hr after 80% cold working~~</figure>

~~Fig. 2.73~~<figure id="fig:Micro structure of AgNi 8020">~~Strain hardening~~[[File:Micro structure of AgNi 8020.jpg|right|thumb|<caption>Micro structure of Ag/Ni 80/20 ~~by cold working~~a) perpendicular to the extrusion direction b) parallel to the extrusion direction</caption>]]</figure></div><div class="clear"></div>

~~Fig. 2.74:~~

~~Softening of Ag/Ni 80/20~~

~~after annealing~~

~~for 1 hr after 80% cold working~~

~~Fig.~~ <figtable id="tab:Contact and Switching Properties of Silver-Nickel (SINIDUR) Materials"><caption>'''Contact and Switching Properties of AgSilver-Nickel Materials'''</~~Ni 90/10 a) perpendicular to the extrusion directionb) parallel to the extrusion direction~~caption>

~~Fig. 2.76~~{| class="twocolortable" style="text-align: ~~Micro structure of~~ left; font-size: 12px"|-!Material !Properties|-|Ag/Ni |High arc erosion resistance at switching currents up to 100A, Resistance against welding for starting current up to 100A, low and over the electrical contact life nearly constant contact resistance for Ag/Ni 90/10 and Ag/Ni 80/20 ~~a) perpendicular~~ , ow and spread-out material transfer under DC load, non-conductive erosion residue on isolating components resulting in only minor change of the dielectric strength of switching devices, good arc moving properties, good arc extinguishing properties, good or sufficient ductility depending on the Ni content, easy to ~~the extrusion direction~~weld and braze|}~~b) parallel t o the extrusion direction~~</figtable>

~~Table 2.23: Contact and Switching Properties of Silver-Nickel (SINIDUR) Materials~~

<figtable id="tab:Application Examples and Forms of Supply for Silver-Nickel (SINIDUR) Materials"><caption>'''Application Examples and Forms of Supplyfor Silver-Nickel ~~(SINIDUR)~~ Materials'''</caption> {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material!Application Examples!Switching or Nominal Current!Form of Supply|-|Ag/Ni 90/10-80/20|Relays Automotive Relays - Resistive load - Motor load|> 10A > 10A|rowspan="9" | '''Semi-finisched Materials:''' Wires, profiles, clad strips, Seam-welded strips, Toplay strips '''Contact Parts:''' Contact tips, solid and composite rivets, Weld buttons, clad, welded, brazed, and riveted contact parts|-|Ag/Ni 90/10, Ag/Ni 85/15-80/20|Auxiliary current switches|≤ 100A|-|Ag/Ni 90/10-80/20|Appliance switches|≤ 50A|-|Ag/Ni 90/10|Wiring devices|≤ 20A|-|Ag/Ni 90/10|Main switches, Automatic staircase illumination switches|≤ 100A|-|Ag/Ni 90/10-80/20|Control Thermostats|> 10A ≤ 50A|-|Ag/Ni 90/10-80/20|Load switches|≤ 20A|-|Ag/Ni 90/10-80/20|Contactors circuit breakers|≤ 100A|-|Ag/Ni 90/10-80/20 paired with Ag/C 97/3-96/4|Motor protective circuit breakers|≤ 40A|-|Ag/Ni 80/20-60/40 paired with Ag/C 96/4-95/5|Fault current circuit breakers|≤ 100A|rowspan="2" | Rods, Profiles, Contact tips, Formed parts, brazed and welded contact parts|-|Ag/Ni 80/20-60/40 paired with Ag/C 96/4-95/5|Power switches|> 100A|}</figtable>

==== Silver-Metal Oxide Materials Ag/CdO, Ag/SnO2, Ag/ZnO====

The family of silver-metal oxide contact materials includes the material groups:silver-cadmium oxide ~~(DODURIT CdO)~~, silver-tin oxide ~~(SISTADOX)~~, and silverzincoxide ~~(DODURIT ZnO)~~. Because of their very good contact and switchingproperties like high resistance against welding, low contact resistance, and higharc erosion resistance, silver-metal oxides have gained an outstanding positionin a broad field of applications. They are mainly ~~are~~ used in low voltage electricalswitching devices like relays, installation and distribution switches, appliances,industrial controls, motor controls, and protective devices ''(<xr id="tab:Application Examples of Silver–Metal Oxide Materials"/>). *'''Silver-cadmium oxide materials'''.

*Silver-cadmium oxide ~~(DODURIT CdO)~~ materialswith 10-15 wt% are produced by both, internal oxidation and powder metallurgical methods.

~~Silver-cadmium oxide (DODURIT CdO) materials with 10-15 wt% are produced~~The manufacturing of strips and wires by ~~both,~~ internal oxidation starts with a molten alloy of silver and ~~powder metallurgical methods '~~cadmium. During a heat treatment below it's melting point in an oxygen rich atmosphere of such a homogeneous alloy, the oxygen diffuses from the surface into the bulk of the material and oxidizes the Cd to CdO in a more or less fine particle precipitation inside the Ag matrix. The CdO particles are rather fine in the surface area and getting larger towards the center of the material (<xr id="fig:Micro structure of AgCdO9010"/>).

~~The~~ During the manufacturing of ~~strips and wires~~ Ag/CdO contact material by internal oxidation ~~starts with a moltenalloy~~ , the processes vary depending on the type of ~~silver and cadmium~~semi-finished material. ~~During~~ For Ag/CdO wires, a ~~heat treatment below it's melting point in aoxygen rich atmosphere in such a homogeneous alloy~~ complete oxidation of the ~~oxygen diffuses from~~AgCd wire is performed, followed by wire-drawing to the ~~surface into the bulk~~ required diameter (<xr id="fig:Strain hardening of internally oxidized AgCdO9010"/> and <xr id="fig:Softening of ~~the~~ internally oxidized AgCdO9010"/>). The resulting material ~~and oxidizes the Cd to CdO~~ is used for example, in ~~a more orless fine particle precipitation inside~~ the production of contact rivets. For Ag ~~matrix. The~~ /CdO ~~particles~~ strip materials two processes are ~~rather~~commonly used: Cladding of an AgCd alloy strip with fine silver, followed by complete oxidation, results in ~~the surface~~ a strip material with a small depletion area ~~and are becoming larger further away towards~~ in the centerof ~~the material '~~it's thickness and an Ag backing suitable for easy attachment by brazing (~~Fig~~sometimes called "Conventional Ag/CdO"). 2Using a technology that allows the partial oxidation of a dual-strip AgCd alloy material in a higher pressure pure oxygen atmosphere, yields a composite Ag/CdO strip material that has - besides a relatively fine CdO precipitation - also an easily brazable AgCd alloy backing.~~83)''~~These materials are mainly used as the basis for contact profiles and contact tips.

During powder metallurgical production, the ~~manufacturing of Ag/CdO contact material~~ powder mixed made by ~~internal oxidation the~~different processes ~~vary depending on the type of semi-finished material.For Ag/CdO wires a complete oxidation of the AgCd wire is performed~~are typically converted by pressing, ~~followedby wire-drawing~~ sintering and extrusion to ~~the required diameter ''(Figs. 2.77~~ wires and ~~2.78)''~~strips. The ~~resultingmaterial is used for example~~ high degree of deformation during hot extrusion, produces a uniform and fine dispersion of CdO particles in the ~~production of contact rivets. For~~ Ag~~/CdO stripmaterials two processes are commonly used: Cladding of an AgCd alloy stripwith fine silver followed by complete oxidation results in a strip material with asmall depletion area in~~ matrix while at the ~~center of it's thickness and~~ same time achieving a ~~Ag backing suitable~~ high density which is advantageous for~~easy attachment by brazing~~ good contact properties (~~sometimes called “Conventional Ag~~<xr id="fig:Micro structure of AgCdO9010P"/~~CdO”~~>)~~. Usinga technology that allows the partial oxidation of a dual~~. ~~These materials (DODURIT CdO ZH) are mainlyused as~~ To obtain a backing suitable for brazing, a fine silver layer is applied by either com-pound extrusion or hot cladding prior to or right after the ~~basis for contact profiles and contact tips~~extrusion.

~~During powder metallurgical production the powder mixed made by differentprocesses are typically converted by pressing~~For larger contact tips, ~~sintering~~ and ~~extrusion to wiresand strips~~especially those with a rounded shape, the single tip Press-Sinter-Repress process (PSR) offers economical advantages. The ~~high degree of deformation during hot extrusion produces~~ powder mix is pressed into a~~uniform~~ die close to the final desired shape, the "green" tips are sintered, and ~~fine dispersion of CdO particles~~ in most cases, the ~~Ag matrix~~ repress process forms the exact final shape while at the sametime ~~achieving a high density which is advantageous for good contact properties''(Fig. 2.84)''. To obtain a backing suitable for brazing~~, ~~a fine silver layer is appliedby either com-pound extrusion or hot cladding prior to or right after~~ increasing the ~~extrusion''(Fig. 2.86)''~~contact density and hardness.

~~For larger contact tips,~~ Using different silver powders and ~~especially those with a rounded shape,~~ minor additives for the ~~single tipPress-Sinter-Repress process (PSR) offers economical advantages. Thepowder mix is pressed in a die close to the final desired shape~~basic Ag and CdO, ~~the “green” tipsare sintered, and in most cases the repress process forms the final exact shapewhile at the same time increasing the~~ starting materials can help influence certain contact ~~density and hardness~~properties for specialized applications.

~~Using different silver powders and minor additives for the basic~~ <div class="multiple-images"><figure id="fig:Strain hardening of internally oxidized AgCdO9010">[[File:Strain hardening of internally oxidized AgCdO9010.jpg|left|thumb|<caption>Strain hardening of internally oxidized Ag ~~and~~ /CdO90/10 by cold working</caption>]]~~starting materials can help influence certain contact properties for specializedapplications.~~</figure>

~~Fig. 2.77~~<figure id="fig:Softening of internally oxidized AgCdO9010">~~Strain hardening~~ [[File:Softening of internally oxidized AgCdO9010.jpg|left|thumb|<caption>Softening of internally oxidized(i.o.) Ag/CdO 90/10 by after annealing for 1 hr after 40% cold working</caption>]]</figure>

~~Fig. 2.78~~<figure id="fig:Strain hardening of AgCdO9010P">~~Softening~~ [[File:Strain hardening of ~~internally oxidized~~AgCdO9010P.jpg|left|thumb|<caption>Strain hardening of powder metallurgical (p.m.) Ag/CdO 90/10 ~~after annealingfor 1 hr after 40%~~ by cold working</caption>]]</figure>

~~Table 2.25~~<figure id="fig: ~~Physical and Mechanical Properties as well as Manufacturing Processes and~~Softening of AgCdO9010P after annealing">~~Forms~~ [[File:Softening of ~~Supply~~ AgCdO9010P after annealing.jpg|left|thumb|<caption>Softening of ~~Extruded Silver Cadmium Oxide~~powder metallurgical Ag/CdO 90/10 after annealing for 1 hr after 40% cold working</caption>]]~~(DODURIT CdO) Contact Materials~~</figure>

~~Fig. 2.79~~<figure id="fig:Strain hardening of AgCdO8812">[[File:Strain hardening of AgCdO8812.jpg|left|thumb|<caption>Strain hardening ofpowder metallurgical Ag/CdO 9088/12</caption>]]</~~10 P by cold working~~figure>

~~Fig. 2.80~~<figure id="fig: Softeningof AgCdO8812WP after annealing">[[File:Softening of AgCdO8812WP after annealing.jpg|left|thumb|<caption>Softening of powder metallurgical Ag/CdO 9088/~~10 P~~ 12 after annealingfor 1 hr after ~~40%~~ different degrees of cold working</caption>]]</figure>

~~Fig. 2.81~~<figure id="fig:Micro structure of AgCdO9010">~~Strain hardening~~[[File:Micro structure of AgCdO9010.jpg|left|thumb|<caption>Micro structure of Ag/CdO 8890/10 i.o. a) close to surface b) in center area</caption>]]</~~12 WP~~figure>

~~Fig. 2.82~~<figure id="fig:Micro structure of AgCdO9010P">~~Softening~~ [[File:Micro structure of AgCdO9010P.jpg|left|thumb|<caption>Micro structure of Ag/CdO 8890/~~12WP after annealing~~10 p.m.: a) perpendicular to extrusion direction b) parallel to extrusion direction</caption>]]~~for 1 hr after different degrees ofcold working~~</figure>

~~Fig. 2.83: Micro structure of Ag~~</~~CdO 90~~div><div class="clear"></~~10 i.o. a) close to surfaceb) in center area~~div>

~~Fig. 2.84: Micro structure of Ag/CdO 90/10 P:~~

~~a) perpendicular to extrusion direction~~

~~b) parallel to extrusion direction~~

~~Fig~~*'''Silver–tin oxide materials'''Over the past years, many Ag/CdO contact materials have been replaced by Ag/SnO2 based materials with 2-14 wt% SnO2 because of the toxicity of Cadmium. This changeover was further favored by the fact that Ag/SnO2~~.85~~ contacts quite often show improved contact and switching properties such as lower arc erosion, higher weld resistance and a significant lower tendency towards material transfer in DC switching circuits (<xr id="tab:~~Micro structure~~ Contact and Switching Properties of Silver–Metal Oxide Materials"/>). Ag/~~CdO 90~~SnO2</~~10 ZH~~sub> materials have been optimized for a broad range of applications by other metal oxide additives and modification in the manufacturing processes that result in different metallurgical, physical and electrical properties (<xr id="tab:1tab2.28"/> and <xr id="tab:tab2.29"/~~CdO layer~~>).

~~Fig~~Manufacturing of Ag/SnO2 by ''internal oxidation'' is possible in principle, but during heat treatment of alloys containing > 5 wt% of tin in oxygen, dense oxide layers formed on the surface of the material prohibit the further diffusion of oxygen into the bulk of the material. 2By adding Indium or Bismuth to the alloy, the internal oxidation is possible and results in materials that typically are rather hard and brittle and may show somewhat elevated contact resistance and is limited to applications in relays.86Adding a brazable fine silver layer to such materials results in a semifinished material, suitable for the manufacture as smaller weld profiles (<xr id="fig: Micro structure of ~~AgCdO 88~~Ag SnO2 92 8 WTOS F"/~~12 WP~~>). Because of their resistance to material transfer and low arc erosion, these materials find for example a broader application in automotive relays (<xr id="tab: aApplication Examples of Silver–Metal Oxide Materials"/>) ~~perpendicular to extrusion direction~~b.

*Silver–tin oxide(SISTADOX)materials~~Over~~ ''Powder metallurgy'' plays a significant role in the ~~past years, many Ag/CdO contact materials have been replaced by~~manufacturing of Ag/SnO2 ~~based~~ contact materials ~~with 2-14 wt%~~ . Besides SnO2 ~~because~~ a smaller amount (<1 wt%) of ~~the toxicity ofCadmium. This changeover was further favored by the fact that Ag~~one or more other metal oxides such as WO3</~~SnO~~sub>, MoO23~~contacts quite often show improved contact and switching properties such aslower arc erosion, higher weld resistance~~, CuO and ~~a significant lower tendencytowards material transfer in DC switching circuits ''(Table~~ /or Bi2~~.30)''. Ag~~</~~SnO~~sub>O23are added. These~~materials have been optimized for a broad range~~ additives improve the wettability of ~~applications by other metal~~the oxide ~~additives~~ particles and ~~modification in~~ increase the viscosity of the Ag melt. They also provide additional benefits to the ~~manufacturing processes that result indifferent metallurgical, physical~~ mechanical and ~~electrical~~ arcing contact properties ''of materials in this group (<xr id="tab:tab2.26"/>).

~~Manufacturing of Ag/SnO~~<~~sub~~figtable id="tab:tab2.26">2<~~/sub~~caption> by ''~~internal oxidation~~'~~' is possible in principle, butduring heat treatment of alloys containing > 5 wt% of tin in oxygen, dense oxidelayers formed on the surface of the material prohibit the further diffusion ofoxygen into the bulk of the material. By adding Indium or Bismuth to the alloy theinternal oxidation is possible and results in materials that typically are rather hardand brittle and may show somewhat elevated contact resistance and is limitedto applications in relays. To make a ductile material with fine oxide dispersion(SISTADOX TOS F) ''(Fig.~~  Physical and ~~extrusion which lead to materials with improved properties inrelays. Adding a brazable fine silver layer to such materials results in a semifinishedmaterial suitable for the manufacture~~ Mechanical Properties as well as ~~smaller weld profiles(SISTADOX WTOS F) ''(Fig. 2.116)''. Because~~ Manufacturing Processes and Forms of Supply of ~~their resistance to materialtransfer and low arc erosion these materials find for example a broaderapplication in automotive relays~~ Extruded Silver-Tin Oxide Contact Materials''~~(Table 2.31)~~''.</caption>

''{| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Silver Content [wt%]!Additives!Theoretical Density [g/cm3]!Electrical Conductivity [MS/m]!Vickers Hardness [HV0,1]!Tensile Strength [MPa]!Elongation (soft annealed) A[%]min.!Manufacturing Process!Form of Supply|-|Ag/SnO2 98/2 SPW|97 - 99|WO3|10,4|59 ± 2|57 ± 15|215|35|Powder Metallurgy|1|-|Ag/SnO2 92/8 SPW|91 - 93|WO3|10,1|51 ± 2|62 ± 15|255|25|Powder ~~metallurgy'' plays a significant role in the manufacturing of~~ Metallurgy|1|-|Ag/SnO2 90/10 SPW|89 - 91|WO3|10|47 ± 5||250|25|Powder Metallurgy|1|-|Ag/SnO2 88/12 SPW|87 - 89|WO3~~contact materials~~|9. ~~Besides~~ 9|46 ± 5|67 ± 15|270|20|Powder Metallurgy|1|-|Ag/SnO2 ~~a smaller amount (~~92/8 SPW4|91 - 93|WO3|10,1|51 ± 2|62 ± 15|255|25|Powder Metallurgy|1,2|-|Ag/SnO2 90/10 SPW4|89 - 91|WO3|10|||||Powder Metallurgy|1 ~~wt%) of one or more~~,2|-|Ag/SnO2 88/12 SPW4 |87 - 89~~other metal oxides such as~~ |WO3|9, 8|46 ± 5|80 ± 10|||Powder Metallurgy|1,2|-|Ag/SnO2 88/12 SPW6|87 - 89|MoO3|9.8|42 ± 5|70 ± 10|||Powder Metallurgy|2|-|Ag/SnO2 97/3 SPW7|96 - 98|Bi2O3 and WO3||||||Powder Metallurgy|2|-|Ag/SnO2 90/10 SPW7|89 - 91|Bi2O3 and WO3|9, 9|||||Powder Metallurgy|2|-|Ag/SnO2 88/12 SPW7|87 - 89|Bi2O3 and WO3|9.8|42 ± 5|70 ± 10|||Powder Metallurgy|2|-|Ag/SnO2 98/2 PMT1|97 - 99|Bi2O3 and CuO |10,4|57 ± 2||215|35|Powder Metallurgy|1,2|-|Ag/SnO2 96/4 PMT1|95 - 97|Bi2O3 and CuO||||||Powder Metallurgy|1,2|-|Ag/SnO2 94/6 PMT1|93 - 95|Bi2O3 and CuO||||||Powder Metallurgy|1,2|-|Ag/SnO2 92/8 PMT1|91 - 93|Bi2O3 and CuO|10|50 ± 2|62 ± 15|240|25|Powder Metallurgy|1,2|-|Ag/SnO2 90/10 PMT1|89 - 91|Bi2O3 andCuO|10|48 ± 2|65 ± 15|240|25|Powder Metallurgy|1,2|-|Ag/or SnO2 88/12 PMT1|87 - 89|Bi2O3 ~~are added. These~~and CuO|9,9|46 ± 5||260|20|Powder Metallurgy|1,2|-|Ag/SnO2 90/10 PE|89 - 91|Bi2O3 and CuO|9,8|48 ± 2|55 - 100|230 - 330|28|Powder Metallurgy|1|-|Ag/SnO2 88/12 PE|87 - 89|Bi2O3 and CuO|9,7|46 ± 5|60 - 106|235 - 330|25|Powder Metallurgy|1|-|Ag/SnO2 88/12 PMT2|87 - 89|CuO|9,9||90 ± 10|||Powder Metallurgy|1,2|-|Ag/SnO2 86/14 PMT3|85 - 87~~additives improve the wettability of the oxide particles~~ |Bi2O3 and ~~increase the viscosity~~CuO|9,8|~~of the~~ |95 ± 10|||Powder Metallurgy|2|-|Ag ~~melt. They also provide additional benefits to the mechanical~~ /SnO2 94/6 LC1|93 - 95|Bi2O3 andIn2O3|9,8|45 ± 5|55 ± 10|||Powder Metallurgy|2|-|Ag/SnO2 90/10 POX1|89 - 91|In2O3|9,9|50 ± 5|85 ± 15|310~~arcing contact properties of materials in this group ''(Table~~ |25|Internal Oxidation|1,2|-|Ag/SnO2 90/10 POX1|87 - 89|In2O3|9,8|48 ± 5|90 ± 15|325|25|Internal Oxidation|1,2|-|Ag/SnO2 90/10 POX1|85 - 87 |In2O3|9,6|45 ± 5|95 ± 15|330|20|Internal Oxidation|1,2~~.26)''.~~|-|}</figtable>

~~In the manufacture the initial powder mixes different processes are appliedwhich provide specific advantages of the resulting materials in respect to theircontact properties ''(Figs.~~ 1 = Wires, Rods, Contact rivets, 2~~.87 – 2.119)''. Some of them are described here asfollows:~~:'''a) Powder blending from single component powders''' In this common process all components including additives that are part of the powder mix are blended as single powders. The blending is usually performed in the dry stage in blenders of different design.= Strips, Profiles, Contact tips

:'''b) Powder blending on the basis of doped powders''' For incorporation of additive oxides in the SnO2 powder the reactive spray process (RSV) has shown advantages. This process starts with a waterbased solution of the tin and other metal compounds. This solution is nebulized under high pressure and temperature in a reactor chamber. Through the rapid evaporation of the water each small droplet is converted into a salt crystal and from there by oxidation into a tin oxide particle in which the additive metals are distributed evenly as oxides. The so created doped AgSnO2 powder is then mechanically mixed with silver powder.

In the manufacture for the initial powder mixes, different processes are applied which provide specific advantages of the resulting materials in respect to their contact properties . Some of them are described here as follows::'''ca) Powder blending ~~based on coated oxide~~ from single component powders''' In this common process ~~tin oxide~~ all components, including additives that are part of the powder is mix, are blended ~~with lower meting additive oxides such~~ as ~~for example Ag2 MoO4 and then heat treated~~single powders. The ~~SnO2 particles are coated~~ blending is usually performed in the dry stage in ~~this step with a thin layer~~ blenders of ~~the additive oxide~~different design.

:'''db) Powder blending ~~based~~ on ~~internally oxidized alloy~~ the basis of doped powders''' ~~A combination~~ For incorporation of additive oxides in the SnO2 powder ~~metallurgy and internal oxidation this~~ , the reactive spray process has shown advantages. This process starts with ~~atomized Ag alloy powder which~~ a waterbased solution of the tin and other metal compounds. This solution is ~~subsequently oxidized~~ nebulized under high pressure and temperature in ~~pure oxygen~~a reactor chamber. ~~During this process~~ Through the rapid evaporation of the Sn water, each small droplet is converted into a salt crystal and ~~other metal components are~~ from there gets transformed ~~to metal~~ by oxidation into a tin oxide ~~and precipitated inside~~ particle in which the additive metals are distributed evenly as oxides. The so created doped AgSnO2 powder is then mechanically mixed with silver ~~matrix of each~~ powder ~~particle~~.

:'''ec) Powder blending based on ~~chemically precipitated compound~~ coated oxide powders''' ~~A silver salt solution~~ In this process, tin oxide powder is ~~added to a suspension of~~ blended with lower melting additive oxides such as for example ~~SnO~~Ag2 ~~together with a precipitation agent. In a chemical reaction silver~~ MoO4 and ~~silver oxide respectively are precipitated around the additive metal oxide particles who act as crystallization sites~~then heat treated. ~~Further chemical treatment then reduces the silver oxide with the resulting precipitated powder being a mix of Ag and~~ The SnO2particles are coated in this step with a thin layer of the additive oxide.

~~Further processing of these differently produced~~ :'''d) Powder blending based on internally oxidized alloy powders ~~follows theconventional processes~~ ''' A combination of ~~pressing, sintering~~ powder metallurgy and ~~hot extrusion to wires andstrips~~internal oxidation this process starts with atomized Ag alloy powder which is subsequently oxidized in pure oxygen. ~~From these contact parts such as contact rivets~~ During this process the Sn and ~~tips~~ other metal components are~~manufactured. To obtain a brazable backing~~ transformed to metal oxide and precipitated inside the ~~same processes as used forAg/CdO are applied. As for Ag/CdO, larger contact tips can also bemanufactured more economically using the press-sinter-repress (PSR) process''(Table 2.27)~~silver matrix of each powder particle.''

~~Fig~~:'''e) Powder blending based on chemically precipitated compound powders''' A silver salt solution is added to a suspension of for example SnO2 together with a precipitation agent. 2In a chemical reaction, silver and silver oxide respectively are precipitated around the additive metal oxide particles, who act as crystallization sites.~~87:Strain hardening~~ Further chemical treatment then reduces the silver oxide with the resulting precipitated powder, being a mix ofAg/and SnO2 ~~92/8 PE by cold working~~.

~~Fig~~Further processing of these differently produced powders follows the conventional processes of pressing, sintering and hot extrusion to wires and strips. From these contact parts, contact rivets and tips are manufactured. 2To obtain a brazable backing, the same processes as used for Ag/CdO are applied.88As for Ag/CdO, larger contact tips can also be manufactured using the press-sinter-repress (PSR) process (<xr id="tab:~~Softening~~ Physical Properties ofAgPowder Metallurgical Silver-Metal Oxide Materials with Fine Silver Backing Produced by the Press-Sinter-Repress Process"/~~SnO~~>)<~~sub~~!--(Table 2.27)-->2.<~~/sub~~div id="figures"> ~~92/8 PE after annealingfor 1 hr after 40% cold working~~

~~Table 2.26~~<div class="multiple-images"><figure id="fig: ~~Physical and Mechanical Properties as well as Manufacturing Processes and~~Strain hardening of AgSNO2 92 8 PE">~~Forms~~ [[File:Strain hardening of ~~Supply~~ AgSNO2 92 8 PE.jpg|left|thumb|<caption>Strain hardening of ~~Extruded Silver-Tin Oxide (SISTADOX) Contact Materials~~Ag/SnO2 92/8 PE by cold working</caption>]]</figure>

~~Fig. 2.89~~<figure id="fig:Softening of AgSnO2 92 8 PE"> ~~Strain hardening~~ [[File:Softening of AgSnO2 92 8 PE.jpg|left|thumb|<caption>Softening ofAg/SnO2 8892/12 8 PE by after annealing for 1 hr after 40% cold working</caption>]]</figure>

~~Fig. 2.90~~<figure id="fig:Strain hardening of Ag SnO2 88 12 PE"> ~~Softening~~ [[File:Strain hardening of Ag SnO2 88 12 PE.jpg|left|thumb|<caption>Strain hardening of Ag/SnO2 88/12 PE~~after annealing for1 hr after 40%~~ by cold working</caption>]]</figure>

~~Fig. 2.91~~<figure id="fig:Softening of Ag SnO2 88 12 PE after annealing"> ~~Strain hardening~~ [[File:Softening of Ag SnO2 88 12 PE after annealing.jpg|left|thumb|<caption>Softening of ~~oxidized~~Ag/SnO2 88/12 ~~PW4 by~~ PE after annealing for 1 hr after 40% cold working</caption>]]</figure>

~~Fig. 2.92~~<figure id="fig:Strain hardening of oxidized AgSnO2 88 12 PW4"> ~~Softening~~ [[File:Strain hardening of oxidized AgSnO2 88 12 PW4.jpg|left|thumb|<caption>Strain hardening of oxidized Ag/SnO2 88/12 PW4 ~~afterannealing for 1 hrafter 30%~~ by cold working</caption>]]</figure>

~~Fig. 2.93~~<figure id="fig:Softening of Ag SnO2 88 12 PW4 after annealing"> ~~Strain hardening~~ [[File:Softening of Ag SnO2 88 12 PW4 after annealing.jpg|left|thumb|<caption>Softening ofAg/SnO2 9888/~~2 PX~~by 12 PW4 after annealing for 1 hr after 30% cold working</caption>]]</figure>

~~Fig. 2.94~~<figure id="fig:Strain hardening of internally oxidized Ag SnO2 88 12 TOS F"> ~~Softening~~ [[File:Strain hardening of internally oxidized Ag SnO2 88 12 TOS F.jpg|left|thumb|<caption>Strain hardening ofinternally oxidized Ag/SnO2 9888/~~2 PXafter annealingfor 1 hr after 80%~~12 TOS F by cold working</caption>]]</figure>

~~Fig 2.95~~<figure id="fig:Softening of Ag SnO2 88 12 TOS F after annealing"> ~~Strain hardening~~[[File:Softening of Ag SnO2 88 12 TOS F after annealing.jpg|left|thumb|<caption>Softening of Ag/SnO2 9288/~~8 PX~~by 12 TOS F after annealing for 1 hr after 30% cold working</caption>]]</figure>

~~Fig. 2.96~~<figure id="fig:Strain hardening of internally oxidized Ag SnO2 88 12P"> ~~Softening~~ [[File:Strain hardening ofinternally oxidized Ag SnO2 88 12P.jpg|left|thumb|<caption>Strain hardening of internally oxidized Ag/SnO2 9288/~~8 PXafter annealing for 1 hrafter 40%~~ 12P by cold working</caption>]]</figure>

~~Fig. 2.97~~<figure id="fig:Softening of Ag SnO2 88 12P after annealing"> ~~Strain hardening~~ [[File:Softening of Ag SnO2 88 12P after annealing.jpg|left|thumb|<caption>Softening of ~~internallyoxidized~~Ag/SnO2 88/12 ~~TOS F~~by SP after annealing for 1 hr after 40% cold working</caption>]]</figure>

~~Fig. 2.98~~<figure id="fig:Strain hardening of Ag SnO2 88 12 WPD"> ~~Softening~~ [[File:Strain hardening of Ag SnO2 88 12 WPD.jpg|left|thumb|<caption>Strain hardening ofAg/SnO2 88/12 ~~TOS F afterannealing for 1 hr after 30%~~WPD by cold working</caption>]]</figure>

~~Fig. 2.99~~<figure id="fig:Softening of Ag SnO2 88 12 WPD after annealing"> ~~Strain hardening~~ [[File:Softening of Ag SnO2 88 12 WPD after annealing.jpg|left|thumb|<caption>Softening of~~internally oxidized~~Ag/SnO2 88/~~12P~~by 12 WPD after annealing for 1 hr after different degrees of cold working</caption>]]</figure>

~~Fig. 2.100~~<figure id="fig:Micro structure of Ag SnO2 92 8 PE"> ~~Softening~~ [[File:Micro structure of Ag SnO2 92 8 PE.jpg|left|thumb|<caption>Micro structure ofAg/SnO2 8892/~~12P~~8 PE: a) perpendicular to extrusion direction b) parallel to extrusion direction</caption>]]~~after annealing for 1 hr after40% cold working~~</figure>

~~Fig. 2.101~~<figure id="fig:Micro structure of Ag SnO2 88 12 PE"> ~~Strain hardening~~ [[File:Micro structure of Ag SnO2 88 12 PE.jpg|left|thumb|<caption>Micro structure ofAg/SnO2 88/12 ~~WPC~~PE: a) perpendicular to extrusion direction b) parallel to extrusion direction</caption>]]~~by cold working~~</figure>

~~Fig. 2.102~~<figure id="fig:Micro structure of Ag SnO2 88 12 PW"> ~~Softening~~ [[File:Micro structure of Ag SnO2 88 12 PW.jpg|left|thumb|<caption>Micro structure of Ag/SnO2 88/12 ~~WPC after annealing~~SPW: a) perpendicular to extrusion direction b) parallel to extrusion direction</caption>]]~~for 1 hr after different degrees of cold working~~</figure>

~~Fig. 2.103~~<figure id="fig:Micro structure of Ag SnO2 88 12 TOS F"> ~~Strain hardening~~ [[File:Micro structure of Ag SnO2 88 12 TOS F.jpg|left|thumb|<caption>Micro structure ofAg/SnO2 8688/12 TOS F: a) perpendicular to extrusion direction b) parallel to extrusion direction</~~14 WPC~~caption>]]~~by cold working~~</figure>

~~Fig. 2.104~~<figure id="fig:Micro structure of Ag SnO2 92 8 WTOS F"> ~~Softening~~ [[File:Micro structure of Ag SnO2 92 8 WTOS F.jpg|left|thumb|<caption>Micro structure of Ag/SnO2 8692/~~14 WPC after annealing~~8 WTOS F: a) perpendicular to extrusion direction b) parallel to extrusion direction,1) AgSnO2 contact layer, 2) Ag backing layer</caption>]]~~for 1 hr after different degrees of cold working~~</figure>

~~Fig. 2.105~~<figure id="fig:Micro structure of Ag SnO2 88 12 WPD"> ~~Strain hardening~~ [[File:Micro structure of Ag SnO2 88 12 WPD.jpg|left|thumb|<caption>Micro structure ofAg/SnO2 88/12 WPD: parallel to extrusion direction 1) AgSnO2 contact layer, 2) Ag backing layer</caption>]]~~by cold working~~</figure>

~~Fig. 2.106:Softening of Ag/SnO~~<~~sub~~div class="clear">2</~~sub~~div> ~~88/12 WPD afterannealing for 1 hr after different degreesof cold working~~

~~Fig. 2.108:~~

~~Softening of Ag/SnO2 88/12 WPX after~~

~~annealing for 1 hr after different degrees~~

~~of cold working~~

~~Fig~~<figtable id="tab:Physical Properties of Powder Metallurgical Silver-Metal Oxide Materials with Fine Silver Backing Produced by the Press-Sinter-Repress Process"><caption>'''Physical Properties of Powder Metallurgical Silver-Metal Oxide Materials with Fine Silver Backing Produced by the Press-Sinter-Repress Process'''</caption><table class="twocolortable"><tr><th rowspan="2">Material</th><th rowspan="2">Additives</th><th rowspan="2">Density[ g/cm3]</th><th rowspan="2">ElectricalResistivity[µS ·cm]</th><th colspan="2">ElectricalConductivity</th><th rowspan="2">VickersHardnessHV 10.~~107:~~</th></tr>~~Strain hardening of~~<tr><th>[%IACS]</th><th>[MS/m]</th></tr>Ag<tr><td>AgCdO 90/10</td><td/><td>10.1</td><td>2.08</td><td>83</td><td>48</td><td>60</td></tr><tr><td>AgCdO 85/15 </td><td/><td>9.9</td><td>2.27</td><td>76</td><td>44</td><td>65</td></tr><tr><td>AgSnO2 90/10</td><td>CuO andBi2 O3</td><td>9.8</td><td>2.22</td><td>78</~~SnO~~td><td>45</td><td>55</td></tr><tr><td>AgSnO2 88/12 ~~WPX~~</td><td>CuO andBi2 O3</td><td>9.6</td><td>2.63</td><td>66</td><td>38</td><td>60</td></tr></table>Form of Support: formed parts, stamped parts, contact tips~~by cold working~~</figtable>

~~Fig~~*'''Silver–zinc oxide materials'''Silver zinc oxide contact materials with mostly 6 - 10 wt% oxide content, including other small metal oxides, are produced exclusively by powder metallurgy [[#figures1|(Figs. 58 – 63)]]. Adding WO3 or Ag2WO4 in the process - as described in the preceding chapter on Ag/SnO2 92- has proven most effective for applications in AC relays, wiring devices, and appliance controls. Just like with the other Ag metal oxide materials, semi-finished materials in strip and wire form are used to manufacture contact tips and rivets. Because of their high resistance against welding and arc erosion Ag/~~8 PE~~ZnO materials present an economic alternative to Cd free Ag-tin oxide contact materials (<xr id="tab: aContact and Switching Properties of Silver–Metal Oxide Materials"/> and <xr id="tab:Application Examples of Silver–Metal Oxide Materials"/>).

~~Fig. 2.110: Micro structure of Ag/SnO2 88/12 PE: a) perpendicular to extrusion direction~~

~~b) parallel to extrusion direction~~

~~Fig~~<figtable id="tab:tab2. 28"><caption>''' Physical and Mechanical Properties as well as Manufacturing Processes and Forms of Supply of ~~Ag/SnO2~~Extruded Silver-Zinc Oxide Contact'''</~~sub~~caption> ~~88/12 PW: a) perpendicular to extrusion directionb) parallel to extrusion direction~~

~~Fig~~{| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Silver Content [wt%]!Additives!Density [g/cm3]!Electrical Resistivity [μΩ·cm]!colspan="2" style="text-align:center"|Electrical Conductivity [% IACS] [MS/m]!Vickers Hardness Hv1!Tensile Strength [MPa]!Elongation (soft annealed) A[%]min. !Manufacturing Process!Form of Supply|-|Ag/ZnO 92/8P |91 - 93||9.8|2.~~112: Micro structure of~~ 22|78|45|60 - 95|220 - 350|25|Powder Metallurgy a) indiv. powders|1|-|Ag/~~SnO~~ZnO 92/8PW25 |91 - 93|Ag2 98WO4|9.6|2 ~~PX:~~ .08|83|48|65 - 105|230 - 340|25|Powder Metallurgy c) coated|1|-|Ag/ZnO 90/10PW25 |89 - 91|Ag2WO4|9.6|2.17|79|46|65 - 100|230 - 350|20|Powder Metallurgy c) coated|1|-|Ag/ZnO 92/8WP |91 - 93||9.8|2.0|86|50|60 - 95|||Powder Metallurgy with Ag backing a) ~~perpendicular to extrusion direction~~individ.|2|-|Ag/ZnO 92/8WPW25 |91 - 93|Ag2WO4|9.6|2.08|83|48|65 - 105|||Powder Metallurgy c) coated|2|-|Ag/ZnO 90/10WPW25 |89 - 91b|Ag2WO4|9.6|2.7|79|46|65 - 110|||Powder Metallurgy c) ~~parallel to extrusion direction~~coated|2|}</figtable>

~~Fig.~~ 1 = Wires, Rods, Contact rivets, 2~~.113: Micro structure of Ag/SnO2 92/8 PX: a) perpendicular to extrusion directionb) parallel to extrusion direction~~= Strips, Profiles, Contact tips

~~Fig. 2.114: Micro structure of Ag/SnO2 88/12 TOS F: a) perpendicular to extrusion direction~~

~~b) parallel to extrusion direction~~

~~Fig. 2.115~~<div class="multiple-images"><figure id="fig:Strain hardening of Ag ZnO 92 8 PW25"> [[File: ~~Micro structure~~ Strain hardening of Ag~~/SnO~~ZnO 92 8 PW25.jpg|left|thumb|<~~sub~~caption>2Strain hardening of Ag/ZnO 92/8 PW25 by cold working</~~sub~~caption> ~~86/14 WPC: a) perpendicular to extrusion direction~~]]~~b) parallel to extrusion direction, 1) AgSnO2~~</~~sub~~figure> ~~contact layer, 2) Ag backing layer~~

~~Fig. 2.116~~<figure id="fig:Softening of Ag ZnO 92 8 PW25"> [[File: ~~Micro structure~~ Softening of Ag~~/SnO~~ZnO 92 8 PW25.jpg|left|thumb|<~~sub~~caption>2<Softening of Ag/~~sub>~~ ZnO 92/8 ~~WTOS F: a) perpendicular to extrusion directionb) parallel to extrusion direction,~~PW25 after annealing for 1~~) AgSnO~~hr after 30% cold working<~~sub~~/caption>2]]</~~sub~~figure> ~~contact layer, 2) Ag backing layer~~

~~Fig. 2.117~~<figure id="fig: ~~Micro structure~~ Strain hardening ofAg ZnO 92 8 WPW25"> [[File:Strain hardening of Ag~~/SnO~~ZnO 92 8 WPW25.jpg|left|thumb|<~~sub~~caption>2Strain hardening of Ag/ZnO 92/8 WPW25 by cold working</~~sub~~caption> ~~88/12 WPD: parallel to extrusion direction~~]]~~1) AgSnO2~~</~~sub~~figure> ~~contact layer, 2) Ag backing layer~~

~~Fig. 2.118~~<figure id="fig: ~~Micro structure~~ Softening ofAg ZnO 92 8 WPW25"> [[File:Softening of Ag~~/SnO~~ZnO 92 8 WPW25.jpg|left|thumb|<~~sub~~caption>2Softening of Ag/ZnO 92/8 WPW25 after annealing for 1hr after different degrees of cold working</~~sub~~caption> ~~88/12 WPX:parallel to extrusion direction~~]]~~1) AgSnO2~~</~~sub~~figure> ~~contact layer, 2) Ag backing layer~~

~~Fig. 2.119~~<figure id="fig:Micro structure of Ag ZnO 92 8 PW25"> [[File: Micro structure of Ag~~/SnO~~ZnO 92 8 Pw25.jpg|left|thumb|<~~sub~~caption>2<Micro structure of Ag/~~sub> 86~~ZnO 92/~~14 WPX~~8 PW25: a) perpendicular to extrusion directionb) parallel to extrusion direction~~, 1) AgSnO~~<~~sub~~/caption>2]]</~~sub~~figure> ~~contact layer, 2) Ag backing layer~~

~~Table 2~~<figure id="fig:Micro structure of Ag ZnO 92 8 WPW25"> [[File:Micro structure of Ag ZnO 92 8 WPW25.27jpg|right|thumb|<caption>Micro structure of Ag/ZnO 92/8 WPW25: ~~Physical Properties of Powder Metallurgical Silver-Metal Oxide Materials~~a) perpendicular to extrusion direction b) parallel to extrusion direction, 1) Ag/ZnO contact layer, 2) Ag backing layer</caption>]]</figure></div>~~with Fine Silver Backing Produced by the Press-Sinter-Repress Process~~<div class="clear"></div>

*'''Silver–zinc oxide (DODURIT ZnO) materials'''

~~Silver zinc oxide (DODURIT ZnO) contact materials with mostly 6 - 10 wt% oxide~~

~~content including other small metal oxides are produced exclusively by powder~~

~~metallurgy ''(Figs. 2.120 – 2.125)'' ''(Table 2.28)''. Adding Ag2WO4 in the process b)~~

~~as described in the preceding chapter on Ag/SnO2 has proven most effective~~

~~for applications in AC relays, wiring devices, and appliance controls. Just like~~

~~with the other Ag metal oxide materials, semi-finished materials in strip and wire~~

~~form are used to manufacture contact tips and rivets.~~

~~Because of their high resistance against welding and arc erosion Ag/ZnO~~

~~materials present an economic alternative to Cd free Ag-tin oxide contact~~

~~materials ''(Tables 2.30 and 2.31)''.~~

<figtable id="tab:tab2.29"><caption>'''Optimizing of Silver–Tin Oxide Materials Regarding their Switching Properties ~~as well as Manufacturing Processes~~ andForming Behavior'''</caption><table class="twocolortable">~~Forms of Supply of Extruded Silver~~<tr><th>Material/Material Group</th><th>Special Properties<th colspan="2"></th></tr><tr><td>Ag/SnO2 PE</td><td>Especially suitable for automotive relays(lamp loads)</td><td>Good formability (contact rivets)</td></tr><tr><td>Ag/SnO2 TOS F</td><td>Especially suited for high inductiveDC loads</td><td>Very good formability (contact rivets)</td></tr><tr><td>Ag/SnO2 WPD</td><td>Especially suited for severe loads (AC-~~Zinc Oxide (DODURIT ZnO~~4) ~~Contact~~and high switching currents</td><td/></tr><tr><td>Ag/SnO2 W TOS F</td><td>Especially suitable for high inductive DCloads</td><td/></tr></table></figtable>

~~Fig. 2.120: Strain hardening of~~

~~Ag/ZnO 92/8 PW25 by cold working~~

~~Fig.~~ <figtable id="tab:Contact and Switching Properties of Silver–Metal Oxide Materials"><caption>'''Contact and Switching Properties of ~~Ag/ZnO 92~~Silver–Metal Oxide Materials'''</~~8 PW25after annealing for 1 hr after 30% cold working~~caption>

~~Fig.~~ {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material!Properties|-|Ag/SnO2~~.122: Strain hardening~~ |Environmentally friendly materials, Very high resistance against welding during current-on-switching, Weld resistance increases with higher oxide contents, Low and stable contact resistance over the life of the device and good temperature rise properties through use ofspecial additives, High arc erosion resistance and contact life, Very low and flat material transfer during DC load switching, Good arc moving and very good arc extinguishing properties|-|Ag/ZnO 92 |Environmentally friendly materials, High resistance against welding during current-on-switching (capacitor contactors), Low and stable contact resistance through special oxide additives, Very high arc erosion resistance at high switching currents, Less favorable than Ag/SnO2 for electrical life and material transfer, With Ag2WO4</~~8 WPW25~~sub> additive especially suitable for AC relays~~by cold working~~|}</figtable>

~~Fig. 2.123: Softening of~~

~~Ag/ZnO 92/8 WPW25 after annealing for~~

~~1hr after different degrees of cold working~~

~~Fig.~~ <figtable id="tab:Application Examples of Silver–Metal Oxide Materials"><caption>'''Application Examples of Silver–Metal Oxide Materials'''</caption><table class="twocolortable"><tr><th>Material</th><th>Application Examples</th></tr><tr><td>Ag/SnO2</td><td>Micro ~~structure of~~ switches, Network relays, Automotive relays, Appliance switches,Main switches, contactors, Fault current protection relays (paired againstAg/C), (Main) Power switches</td></tr><tr><td>Ag/ZnO 92</td><td>Wiring devices, AC relays, Appliance switches, Motor-protective circuitbreakers (paired with Ag/~~8 Pw25: a~~Ni or Ag/C), Fault current circuit breakers paired againct Ag/C, (Main) ~~perpendicular to extrusion direction~~Power switches</td></tr></table>~~b) parallel to extrusion direction~~</figtable>

~~Fig~~====Silver–Graphite Materials====Ag/C contact materials are usually produced by powder metallurgy with graphite contents of 2 – 6 wt% (<xr id="tab:tab2. 32"/>). The earlier typical manufacturing process of ~~Ag/ZnO 92/8 WPW25:a~~single pressed tips by pressing - sintering - repressing (PSR) ~~perpendicular to~~ has been replaced in Europe for quite some time by extrusion ~~directionb) parallel~~ . In North America and some other regions however the PSR process is still used to ~~extrusion direction, 1) Ag/ZnO contact layer, 2) Ag backing layer~~some extend mainly for cost reasons.

~~Table~~ The extrusion of sintered billets is now the dominant manufacturing method for semi-finished AgC materials. The hot extrusion process results in a high density material with graphite particles stretched and oriented in the extrusion direction [[#figures4|(Figs. 68 – 71)]]. Depending on the extrusion method in either rod or strip form, the graphite particles can be oriented in the finished contact tips perpendicular or parallel to the switching contact surface (<xr id="fig: ~~Optimizing~~ Micro structure of ~~Silver–Tin Oxide Materials Regarding their SwitchingProperties~~ Ag C 95 5"/> and ~~Forming Behavior~~<xr id="fig:Micro structure of Ag C 96 4 D"/>).

~~Table 2~~Since the graphite particles in the Ag matrix of Ag/C materials prevent contact tips from directly being welded or brazed, a graphite free bottom layer is required.~~30: Contact and Switching Properties~~ This is achieved by burning out (de-graphitizing) the graphite selectively on one side of ~~Silver–Metal Oxide Materials~~the tips.

~~Table 2~~Ag/C contact materials exhibit on the one hand an extremely high resistance to contact welding but on the other have a low arc erosion resistance.~~31: Application Examples~~ This is caused by the reaction of ~~Silver–Metal Oxide Materials~~graphite with the oxygen in the surrounding atmosphere at the high temperatures created by the arcing. The weld resistance is especially high for materials with the graphite particle orientation parallel to the arcing contact surface. Since the contact surface after arcing consists of pure silver, the contact resistance stays consistantly low during the electrical life of the contact parts.

~~====Silver–Graphite (GRAPHOR)-Materials====~~A disadvantage of the Ag/C ~~(GRAPHOR) contact~~ materials ~~are usually produced by powder metallurgy~~is their rather high erosion rate. In materials with parallel graphite ~~contents~~ orientation this can be improved, if a part of ~~2 – 5 wt% ''~~the graphite is incorporated into the material (~~Table 2.32~~Ag/C DF)~~''. The earlier typicalmanufacturing process~~ in the form of fibers (<xr id="fig:Micro structure of ~~single pressed tips by pressing~~ Ag C DF"/>)<!- ~~sintering~~ - ~~repressing~~(~~PSR~~Fig. 2.133) ~~has been replaced in Europe for quite some time~~ -->. The weld resistance is determined by ~~extrusion. In NorthAmerica and some other regions however~~ the ~~PSR process is still used to someextend mainly for cost reasons~~total content of graphite particles.

~~The extrusion~~ Ag/C tips with vertical graphite particle orientation are produced in a specific sequence: Extrusion to rods, cutting of double thickness tips, burning out of ~~sintered billets is now the dominant manufacturing method~~ graphite to a controlled layer thickness, and a second cutting to single tips. Such contact tips are especially well suited for~~semi-finished AgC materials ''(Figs. 2.126 – 2.129)''. The hot extrusion processresults in~~ applications which require both, a high ~~density material with graphite particles stretched~~ weld resistance and ~~oriented inthe extrusion direction ''~~a sufficiently high arc erosion resistance (~~Figs~~<xr id="tab:tab2. 33"/>). ~~Depending on the extrusionmethod in either rod or strip form the graphite particles can be oriented in thefinished contact~~ For attachment of Ag/C tips ~~perpendicular (GRAPHOR) or parallel (GRAPHOR D) to theswitching contact surface ''(Figs. 2.131~~ welding and ~~2.132)''~~brazing techniques are applied.

~~Since~~ Welding the actual process depends on the material's graphite ~~particles in the Ag matrix of~~ orientation. For Ag/C ~~materials prevent contact~~tips ~~from directly being welded or brazed, a~~ with vertical graphite ~~free bottom layer isrequired~~orientation the contacts are assembled with single tips. ~~This~~ For parallel orientation a more economical attachment starting with contact material in strip or profile tape form is ~~achieved by either burning out (de-graphitizing)~~ used in integrated stamping and welding operations with the tape fed into the weld station, cut off to tip form and then welded to the carrier material before forming the ~~graphiteselectively on one side of~~ final contact assembly part. For special low energy welding, the ~~tips or by compound extrusion of a~~ Ag/C ~~billetcovered~~ profile tapes can be pre-coated with a ~~fine silver shell~~thin layer of high temperature brazing alloys such as CuAgP.

In a rather limited way, Ag/C ~~contact materials exhibit on the one hand an extremely high resistance tocontact welding but on the other have a low arc erosion resistance. This iscaused by the reaction of~~ with 2 – 3 wt% graphite ~~with the oxygen~~ can be produced in ~~the surroundingatmosphere at the high temperatures created by the arcing. The weld resistanceis especially high for materials~~ wire form and headed into contact rivet shape with ~~the graphite particle orientation parallel to thearcing contact surface. Since the contact surface after arcing consists of puresilver the contact resistance stays consistently~~ low ~~during the electrical life of thecontact parts~~head deformation ratios.

~~A disadvantage of the~~ The main applications for Ag/C materials are protective switching devices such as miniature molded case circuit breakers, motor-protective circuit breakers, and fault current circuit breakers, where during short circuit failures, highest resistance against welding is ~~their rather high erosion rate~~required (<xr id="tab:tab2. ~~In materialswith parallel graphite orientation this can be improved if part of the graphite isincorporated into the material in the form of fibers (GRAPHOR DF~~34"/>)~~, ''~~.~~The weld~~ For higher currents the low arc erosion resistance of Ag/C is ~~determined~~ compensated by ~~the total content of graphite particles~~asymmetrical pairing with more erosion resistant materials such as Ag/Ni, Ag/W and Ag/WC.

<div class="multiple-images"><figure id="fig:Strain hardening of Ag/C ~~tips with vertical graphite particle orientation are produced in a specific~~96 4 D">~~sequence~~[[File: ~~Extrusion to rods, cutting~~ Strain hardening of ~~double thickness tips, burning out ofgraphite to a controlled layer thickness, and a second cutting to single tips.Such contact tips are especially well suited for applications which require both,a high weld resistance and a sufficiently high arc erosion resistance ''(Table 2~~Ag C 96 4 D.~~33)''.For attachment~~ jpg|left|thumb|<caption>Strain hardening of Ag/C ~~tips welding and brazing techniques are applied.~~96/4 by cold working</caption>]]</figure>

~~welding the actual process depends on the material's graphite orientation. For~~<figure id="fig:Softening of Ag C 96 4 D"> [[File:Softening of Ag/C ~~tips with vertical graphite orientation the contacts are assembled withsingle tips~~96 4 D. ~~For parallel orientation a more economical attachment starting withcontact material in strip or profile tape form is used in integrated stamping andwelding operations with the tape fed into the weld station, cut off to tip form andthen welded to the carrier material before forming the final contact assemblypart. For special low energy welding the~~ jpg|left|thumb|<caption>Softening of Ag/C ~~profile tapes GRAPHOR D and DF~~96/4 after annealing</caption>]]~~can be pre-coated with a thin layer of high temperature brazing alloys such asCuAgP.~~</figure>

~~In a rather limited way,~~ <figure id="fig:Strain hardening of Ag C DF"> [[File:Strain hardening of Ag C DF.jpg|left|thumb|<caption>Strain hardening of Ag/C ~~with 2 – 3 wt% graphite can be produced in wire~~DF by cold working</caption>]]~~form and headed into contact rivet shape with low head deformation ratios.~~</figure>

~~The main applications for~~ <figure id="fig:Softening of Ag/C ~~materials are protective switching devices such~~DF after annealing"> ~~as miniature molded case circuit breakers, motor-protective circuit breakers,and fault current circuit breakers, where during short circuit failures highestresistance against welding is required ''(Table 2.34)''~~[[File:Softening of Ag C DF after annealing. ~~For higher currents the lowarc erosion resistance~~ jpg|left|thumb|<caption>Softening of Ag/C ~~is compensated by asymmetrical pairing with~~DF after annealing</caption>]]~~more erosion resistant materials such as Ag~~</~~Ni and Ag/W.~~figure>

~~Fig. 2.126~~<figure id="fig:Micro structure of Ag C 97 3"> ~~Strain hardening~~[[File:Micro structure of Ag C 97 3.jpg|left|thumb|<caption>Micro structure of Ag/C 9697/3: a) perpendicular to extrusion direction b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag backing layer</~~4 D~~caption>]]~~by cold working~~</figure>

~~Fig. 2.127~~<figure id="fig:Micro structure of Ag C 95 5"> ~~Softening~~ [[File:Micro structure of Ag C 95 5.jpg|left|thumb|<caption>Micro structure of Ag/C 9695/~~4 D after~~5: a) perpendicular to extrusion direction b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag backing layer</caption>]]~~annealing~~</figure>

~~Fig. 2.128~~<figure id="fig: ~~Strain hardening~~Micro structure of Ag C 96 4 D"> [[File:Micro structure of Ag C 96 4 D.jpg|left|thumb|<caption>Micro structure of Ag/C ~~DF by cold working~~96/4: a) perpendicular to extrusion direction b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag backing layer</caption>]]</figure>

~~Fig. 2.129~~<figure id="fig: ~~Softening~~Micro structure of Ag C DF"> [[File:Micro structure of Ag C DF.jpg|left|thumb|<caption>Micro structure of Ag/C DF ~~after annealing~~: a) perpendicular to extrusion direction b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag/Ni 90/10 backing layer</caption>]]</figure></div><div class="clear"></div>

~~Fig~~<figtable id="tab:tab2. 32"><caption>'''Physical Properties of ~~Ag/C 97~~Silver–Graphite Contact Materials'''</~~3: a) perpendicular to extrusion directionb) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag backing layer~~caption>

~~Fig~~{| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Silver Content [wt%]!Density [g/cm3]!Melting Point [°C]!Electrical Resistivity [μΩ·cm]!colspan="2" style="text-align:center"|Electrical Conductivity [% IACS] [MS/m]!Vickers-Hardnes HV10 42 - 45|-|Ag/C 98/2|97. 25 - 98.5|9.5|960|1.85 - 1.~~131: Micro structure of~~ 92|90 - 93|48 - 50|42 - 44|-|Ag/C 9597/3|96.5 - 97.5~~: a) perpendicular to extrusion directionb) parallel to extrusion direction,~~ |9.1|960|1) .92 - 2.0|86 - 90|45 - 48|41 - 43|-|Ag/C ~~contact layer,~~ 96/4|95.5 - 96.5|8.7|960|2.04 - 2) .13|81 - 84|42 - 46|40 - 42|-|Ag ~~backing layer~~/C 95/5|94.5 - 95.5|8.5|960|2.12 - 2.22|78 - 81|40 - 44|40 - 60|-|AgC DF GRAPHOR DF[[#text-reference1|1]]|95.7 - 96.7|8.7 - 8.9|960|2.27 - 2.50|69 - 76|40 - 44|-|}<div id="text-reference1">1 Graphite content 3.8 wt%, Graphite particles and fibers parallel to switching surface</div></figtable>

~~Fig. 2.132: Micro structure of Ag/C 96/4 D: a) perpendicular to extrusion direction~~

~~b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag backing layer~~

~~Fig. 2.133: Micro structure of Ag/C DF: a) perpendicular to extrusion direction~~

~~b) parallel to extrusion direction, 1) Ag/C contact layer, 2) Ag/Ni 90/10 backing layer~~

~~Table 2.32: Physical Properties of Silver–Graphite (GRAPHOR) Contact Materials~~

<figtable id="tab:tab2.33"><caption>'''Contact and Switching properties of Silver–Graphite ~~(GRAPHOR)~~ Contact Materials'''</caption><table class="twocolortable"><tr><th>Material</th><th>Properties</th></tr><tr><td>Ag/C</td><td>Highest resistance against welding during make operations at high currents,High resistance against welding of closed contacts during short circuit,Increase of weld resistance with higher graphite contents, Low contact resistance,Low arc erosion resistance, especially during break operations, Higher arc erosion with increasing graphite contents, at the same time carbon build-up on switching chamber walls increases, silver-graphite with vertical orientation has better arc erosion resistance, parallel orientation has better weld resistance,Limited arc moving properties, therefore paired with other materials,Limited formability,Can be welded and brazed with decarbonized backing, GRAPHOR DF is optimized for arc erosion resistance and weld resistance</td></tr></table></figtable>

~~Table 2.34: Application Examples and Forms of Supply of Silver–~~

~~Graphite (GRAPHOR) Contact Materials~~

~~Pre~~<figtable id="tab:tab2.34"><caption>'''<!--Table 2.34:--~~Production~~ >Application Examples and Forms of Supply of Silver– Graphite Contact Materials'''</caption><table class="twocolortable"><tr><th>Material</th><th>Application Examples</th><th>Form of Supply</th></tr><td>Ag/C 98/2</td><td>Motor circuit breakers, paired with Ag/Ni</td><td>Contact tips, brazed and welded contact parts, some contact rivets Contact profiles (~~Bild~~weld tapes), Contact tips, brazed and welded contact parts</td></tr><tr><td>Ag/C 97/3Ag/C 96/4Ag/C 95/5Ag/C DF</td><td>Circuit breakers, paired with Cu, Motor-protective circuit breakers, paired with Ag/Ni,Fault current circuit breakers, paired with Ag/Ni, Ag/W, Ag/WC, Ag/SnO2, Ag/ZnO,(Main) Power switches, paired with Ag/Ni, Ag/W</td><td>Contact tips, brazed and welded contactparts, some contact rivets withAg/C97/3</td></tr></table></figtable>

==References==

[[Contact Materials for Electrical Engineering#References|References]]

[[de:Werkstoffe_auf_Silber-Basis]]

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