Changes

For Pure Gold is besides Platinum the chemically most electrical contact applications gold alloys are usedstable of all precious metals. Depending on the alloying metal the melting In its pure form it is performed either under in not very suitable for use as a reducing atmosphere or contact material in a vacuum. The choice electromechanical devices because of alloying metals depends on the intended use of the resulting its tendency to stick and cold-weld at even low contact materialforces. The binary Au alloys with typically <10 wt% of other precious metals such as Pt, Pd, In addition it is not hard or Ag or non-precious metals like Ni, Co, strong enough to resist mechanical wear and Cu are the more commonly used ones ''exhibits high material losses under electrical arcing loads (Table 2.2<xr id="tab:Contact_and_Switching_Properties_of_Gold_and_Gold_Alloys"/>)''. On one hand these alloy additions improve the mechanical strength and electrical switching properties but on the other hand reduce the electrical conductivity and chemical corrosion resistance ''<!--(FigTab. 2.24)'' to varying degrees-->. This limits its use in form of thin electroplated or vacuum deposited layers.

[[FileFor most electrical contact applications, gold alloys are used. Depending on the alloying metal, the melting is performed either under a reducing atmosphere or in a vacuum. The choice of alloying metals depends on the intended use of the resulting contact material. The binary Au alloys with typically < 10 wt% of other precious metals such as Pt, Pd, Ag or non-precious metals like Ni, Co and Cu are the more commonly used ones (<xr id="tab:Physical Properties of Gold and Gold-Alloys"/>)<!--(Tab. 2.jpg|right|thumb|Physical Properties of Gold and Gold2)-Alloys]][[File:Influence of 1-10 atomic of different>.jpg|right|thumb|Influence of 1-10 atomic% of different alloying metals On one hand these alloy additions improve the mechanical strength and electrical switching properties but on the other hand reduce the electrical resistivity of gold conductivity and chemical corrosion resistance (<xr id="fig:Influence_of_1_10_atomic_of_different"/>)<!--(according to JFig. O2. Linde2)]]--> to varying degrees.

Under the aspect of reducing the gold content , ternary alloys with a gold content of approximately 70 wt% and additions of Ag and Cu or Ag and Ni resp., for example AuAg25Cu5 or AuAg20Cu10 are used , which exhibit for many applications good mechanical stability , while at the same time have sufficientresistance against the formation of corrosion layers ''(Table 2.3)''. Other ternary alloys based on the AuAg system are AuAg26Ni3 and AuAg25Pt6. These alloys are mechanically similar to the AuAgCu alloys but have significantly higher oxidation resistance at elevated temperatures ''(Table 2.4)''.[[File<xr id="tab:Mechanical Properties of Gold and Gold -Alloys.jpg|right|thumb|Mechanical Properties of Gold and Gold Alloys]]'''Table 2.4: Contact and Switching Properties of Gold and Gold Alloys'''<table border="1" cellspacing="0" style="border-collapse:collapse"><tr><td><p class="s11">Material</p>)</td><td><p class="s12">Properties</p></td></tr><tr><td><p class="s11">Au</p></td><td><p class="s12">Highest corrosion resistance, low</p><p class="s12">hardness</p></td><td><p class="s12">High electr!--(Table 2. conductivity,</p><p class="s12">strong tendency to cold welding</p></td></tr><tr><td><p class="s11">AuAg8</p></td><td><p class="s12">High corrosion resistance, low thermo</p><p class="s12">e.m.f.</p></td><td><p class="s12">Low contact resistance</p></td></tr><tr><td><p class="s11">AuPt10</p><p class="s11">AuPd5</p></td><td><p class="s12">Very high corrosion resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg10 3)-- 30</p></td><td><p class="s12">Mostly corrosion resistant</p></td><td><p class="s12">Higher hardness</p></td></tr><tr><td><p class="s11">AuNi5</p><p class="s11">AuCo5</p></td><td><p class="s12">High corrosion resistance, low</p><p class="s12">tendency to material transfer</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg25Pt6</p></td><td><p class="s12">High corrosion resistance, low contact resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg26Ni3</p><p class="s11">AuAg25Cu5</p><p class="s11">AuAg20Cu10</p></td><td><p class="s12">Limited corrosion resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuPd40</p><p class="s11">AuPd35Ag10</p><p class="s11">AuCu14Pt9Ag4</p></td><td><p class="s12">High corrosion resistance</p></td><td><p class="s12">High hardness and mechanical</p><p class="s12">wear resistance</p></td></tr></table>Caused by higher gold prices over the past years the development of alloys with further reduced gold content had a high priority. The starting point has been the AuPd system which has continuous solubility of the two components. Besides the binary alloy of AuPd40 and the ternary one AuPd35Ag9 other multiple component alloys were developed. These alloys typically have < 50 wt% Au and often can be solution hardened in order to obtain even higher hardness and tensile strength. They are mostly used in sliding contact applications.

<figtable id="tab:Commonly Used Grades of Gold alloys are used in the form "><caption>'''Commonly Used Grades of welded wire or profile Gold<!--(also called weldtapes2.1), segments, contact rivets, and stampings produced from clad stripmaterials. The selection of the bonding process is based on the cost for the joining process, and most importantly on the economical aspect of using the-->'''</caption>least possible amount of the expensive precious metal component.<table class="twocolortable">

Besides being used as switching contacts in relays <tr><th><p class="s11">Designation</p></th><th><p class="s11">Composition Au</p><p class="s11">(min. content)</p></th><th><p class="s11">Impurites ppm</p></th><th><p class="s12">Remarks on forms and pushbuttonsapplication</p></th></tr><tr><td><p class="s11">Electronic Gold</p><p class="s11">Gold</p></td><td><p class="s11">99.999</p></td><td><p class="s11">Cu &lt; 3</p><p class="s11">Ag &lt; 3</p><p class="s11">Ca &lt; 1</p><p class="s11">Mg &lt;1</p><p class="s11">Fe &lt; 1</p></td><td><p class="s12">Wires, gold strips, alloying metal for semiconductors, electronic components</p></td></tr><tr><td><p class="s11">Pure Gold</p></td><td><p class="s11">99.995</p></td><td><p class="s11">Cu &lt; 10</p><p class="s11">Ag &lt; 15</p><p class="s11">Ca &lt; 20</p><p class="s11">Mg &lt; 10</p><p class="s11">Fe &lt; 3</p><p class="s11">Si &lt; 10</p><p class="s11">Pb &lt; 20</p></td><td><p class="s12">Granulate for high purity alloys are also applied in the design of connectors as well as sliding contacts for potentiometers, sensorsstrips, slip ringstubing, and brushes in miniature DC motors ''(Table 2.5)''profiles</p></td></tr><tr><td><p class="s11">Ingot Grade-Gold</p></td><td><p class="s11">99.95</p></td><td><p class="s11">Cu &lt; 100</p><p class="s11">Ag &lt; 150</p><p class="s11">Ca &lt; 50</p><p class="s11">Mg &lt; 50</p><p class="s11">Fe &lt; 30</p><p class="s11">Si &lt; 10</p></td><td><p class="s12">Alloys, commonly used grade</p></td></tr></table></figtable><br/><br/>

'''Table 2.5<figtable id="tab: Application Examples and Forms Physical Properties of Gold and Gold -Alloys'''<table border="1" cellspacing="0" style="border-collapse:collapse"><trcaption><td><p class="s11">Material</p></td><td><p class="s12">Application Examples</p></td><td><p class="s12">Form '''Physical Properties of Application</p></td></tr><tr><td><p class="s11">Pure Gold</p><p class="s11">(electroplated)</p></td><td><p class="s12">Corrosion protection layer for contact parts, stationary contacts, bonding surfaces</p></td><td><p class="s12">Electroplated coatings, bond surface layers</p></td></tr><tr><td><p class="s11">Hard Gold</p><p class="s11">(sputtered)</p></td><td><p class="s12">Contact parts for connectors and switches, sliding contact tracks, bonding surfaces</p></td><td><p class="s12">Electroplated coatings on contact rivets and stamped parts</p></td></tr><tr><td><p class="s11">Hard Gold</p><p class="s11">(sputtered)</p></td><td><p class="s12">Contacts in switches and relays for low loads, electronic signal relays</p></td><td><p class="s12">Contact surface layer on miniature</p><p class="s12">profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuAg8</p></td><td><p class="s12">Dry circuit switching contacts, electronic</p><p class="s12">signal relays</p></td><td><p class="s12">Contact rivets, welded contact</p><p class="s12">parts</p></td></tr><tr><td><p class="s11">AuAg20</p></td><td><p class="s12">Switching contacts for low loads, electronic</p><p class="s12">signal relays</p></td><td><p class="s12">Contact rivets, welded contact</p><p class="s12">parts</p></td></tr><tr><td><p class="s11">AuAg25Cu5</p><p class="s11">AuAg25Cu10</p><p class="s11">AuAg26Ni3</p></td><td><p class="s12">Contact parts for connectors, switches and relays</p></td><td><p class="s12">Claddings on Cu alloys, contact rivets, contact layer on micro profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuNi5</p><p class="s11">AuCo5 (heterogen)</p></td><td><p class="s12">Contacts in switches and relays for low and medium loads, material transfer resistant contacts</p></td><td><p class="s12">Contact rivets, welded contact parts, contact layer on miniature profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuPt10</p><p class="s11">AuAg25Pt6</p></td><td><p class="s12">Contacts for highest chemical corrosion resistance in switches and relays</p></td><td><p class="s12">Contact rivets, contact layer on micro profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuCu14Pt9Ag4</p></td><td><p class="s12">Sliding contacts for measurement data transfer</p></td><td><p class="s12">Wire-formed parts</p></td></tr>Alloys'''</tablecaption>

'''Table 2.1: Commonly Used Grades of Gold'''<table border{| class="1" cellspacing="0twocolortable" style="bordertext-align: left; font-collapsesize:collapse12px">|-!Material!Gold<trbr/>Content<tdbr/>[wt.%]!Density<p class="s11">Designation<br/p><[g/td>cm<tdsup><p class="s11">Composition Au3</psup>]!Melting Point<p class="s11">(min. content)<br/p>or Range<br/td>[°C]!Electrical<td><p class="s11">Impurites ppm<br/p>Resistivity<br/td>[µΩ*cm]!Electrical<td><p class="s12">Remarks on forms and application<br/p>Conductivity<br/td><[MS/tr><tr><td><p class="s11">Electronic Glodm]!Thermal<br/p><p class="s11">GoldConductivity<br/p><[W/td><td><p class="s11">99(m*K)]!Temp. Coeff.999of<br/p>the electr. Resistance<br/td>[10<tdsup><p class="s11">Cu &lt; -3<sup/p><p class="s11">Ag &lt; 3</p><p class="s11">Ca &lt; 1K]!Modulus of<br/p><p class="s11">Mg &lt;1Elasticity<br/p><p class="s11"[GPa]|-|Au (99,95)| >Fe &lt; 99,95|19,3|1064|2,32|43|317|4,0|79|-|AuAg8|92|18,1</p></td><td><p class="s12">Wires|1058|6, strips13|16, alloying metal for semiconductors3|147|1,25|82|-|AuAg20|80|16, electronic components</p></td></tr><tr><td><p class="s11">Pure Gold</p></td><td><p class="s11">99.995</p></td><td><p class="s11">Cu &lt; 4|1035 - 1045|10</p><p class="s11">Ag &lt; 15</p><p class="s11">Ca &lt; 20</p><p class="s11">Mg &lt; ,0|10</p><p class="s11">Fe &lt; |75|0,86|89|-|AuNi5|95|18,3</p><p class="s11">Si &lt; 10</p><p class="s11">Pb &lt; 20</p></td><td><p class="s12">Granulate for high purity alloys|995 - 1018|13,5|7,4|53|0,71|83|-|AuCo5|95|18,2|1010 - 1015|55, strips6|1, tubing8||0, profiles</p></td></tr><tr><td><p class="s11">Ingot Grade68|88|-Gold</p></td><td><p class="s11">99|AuCo5 (het.)|95</p></td><td><p class="s11">Cu &lt; 100</p><p class="s11">Ag &lt; 150</p><p class="s11">Ca &lt; 50</p><p class="s11">Mg &lt; 50</p><p class="s11">Fe &lt; 30</p><p class="s11">Si &lt; 10</p></td><td><p class="s12">Alloys|18,2|1010 - 1015|5,99|16,7||||-|AuAg25Cu5|70|15,2|950 - 980|12,2|8,2||0,75|89|-|AuAg20C10|70|15,1|865 - 895|13,3|7,5|66|0,52|87|-|AuAg26Ni3|71|15,4|990 - 1020|11,0|9,1|59|0,88|114|-|AuPt10|90|19,5|1150 - 1190|12,5|8,0|54|||-|AuAg25Pt6|69|16,1|1060|15,9|6,3|46|0,54|93|-|AuCu14Pt9Ag4|73|16,0|955|14, commonly used grade</p></td></tr>3 - 25|4 - 7||||-|}</tablefigtable>

Fig. 2.3<div class="multiple-images"><figure id="fig: Phase diagram of goldplatinumInfluence_of_1_10_atomic_of_different">[[File:Phase diagram Influence of 1-10 atomic of goldplatinumdifferent.jpg|rightleft|thumb|Phase diagram <caption>Fig 2.2 Influence of goldplatinum1-10 atomic% of different alloying metals on the electrical resistivity of gold (according to J. O. Linde)</caption>]]</figure></div><div class="clear"></div>

Fig<figtable id="tab:Mechanical Properties of Gold and Gold-Alloys"><caption>'''<!--Tab. 2.53: Phase diagram -->Mechanical Properties of goldGold and Gold-copperAlloys'''</caption>{| class="twocolortable" style="text-align: left; font-size: 12px"|-!Material !Hardness Condition!Tensile Strength Rm [MPa] min.!Elongation A₁₀ [File:Phase diagram of gold%] min.!Vickers Hardness HV|-|Au|R 140<br />R 170<br />R 200<br />R 240|140<br />170<br />200<br />240|30<br />3<br />2<br />1|20<br />50<br />60<br />70|- |AuAg20|R 190<br />R 250<br />R 320<br />R 390|190<br />250<br />320<br />390|25<br />2<br />1<br />1|38<br />70<br />95<br />115|-|AuAg30|R 220<br />R 260<br />R 320<br />R 380|220<br />260<br />320<br />380|25<br />3<br />1<br />1|45<br />75<br />95<br />110|-|AuAg25Cu5|R 400<br />R 470<br />R 570<br />R 700|400<br />470<br />570<br />700|25<br />4<br />2<br />2|90<br />120<br />160<br />185|-|AuAg20Cu10|R 480<br />R 560<br />R 720<br />R 820|480<br />560<br />720<br />820|20<br />3<br />1<br />1|125<br />145<br />190<br />230|-|AuAg26Ni3|R 350<br />R 420<br />R 500<br />R 570|350<br />420<br />500<br />570|20<br />2<br />1<br />1|85<br />110<br />135<br />155|-|AuAg25Pt6|R 280<br />R 330<br />R 410<br />R 480|280<br />330<br />410<br />480|18<br />2<br />1<br />1|60<br />90<br />105<br />125|-|AuCo5|R 340<br />R 390<br />R 450<br />R 530|340<br />390<br />450<br />530|10<br />2<br />1<br />1|95<br />105<br />120<br />150|-copper|AuCo5 prec.jpghardened|heterogeneous|360|right3|thumb110-130|-|AuNi5|R 380<br />R 450<br />R 560<br />R 640|380<br />450<br />560<br />640|25<br />3<br />2<br />1|115<br />135<br />160<br />190|-|AuPt10|R 260<br />R 310<br />R 370<br />R 410|260<br />310<br />370<br />410|20<br />2<br />1<br />1|80<br />90<br />100<br />105|Phase diagram of gold-copper]]|AuCu14Pt9Ag4|R 620<br />R 700<br />R 850<br />R 950<br />prec.hardened|620<br />700<br />850<br />950<br />900|20<br />3<br />2<br />1<br />3|190<br />225<br />260<br />270<br />280|}</figtable>

FigOther ternary alloys based on the AuAg system are AuAg26Ni3 and AuAg25Pt6. These alloys are mechanically similar to the AuAgCu alloys but have significantly higher oxidation resistance at elevated temperatures (<xr id="tab:Contact_and_Switching_Properties_of_Gold_and_Gold_Alloys"/>)<!--(Table 2.6: Phase diagram of gold4)-nickel[[File:Phase diagram of gold-nickel>.jpg|right|thumb|Phase diagram of gold-nickel]]

Fig. <figtable id="tab:Contact_and_Switching_Properties_of_Gold_and_Gold_Alloys"><caption>'''<!--Table 2.74: Phase diagram -->Contact and Switching Properties of gold-cobaltGold and Gold Alloys'''</caption><table class="twocolortable"> [[File:Phase diagram of gold-cobalt<tr><th><p class="s11">Material</p></th><th><p class="s12">Properties<th colspan="2"></p></th></tr><tr><td><p class="s11">Au</p></td><td><p class="s12">Highest corrosion resistance, low</p><p class="s12">hardness</p></td><td><p class="s12">High electr. conductivity,</p><p class="s12">strong tendency to cold welding</p></td></tr><tr><td><p class="s11">AuAg8</p></td><td><p class="s12">High corrosion resistance, low thermo</p><p class="s12">e.m.f.jpg|right|thumb|Phase diagram of gold</p></td><td><p class="s12">Low contact resistance</p></td></tr><tr><td><p class="s11">AuPt10</p><p class="s11">AuPd5</p></td><td><p class="s12">Very high corrosion resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg10 -cobalt]]30</p></td><td><p class="s12">Mostly corrosion resistant</p></td><td><p class="s12">Higher hardness</p></td></tr><tr><td><p class="s11">AuNi5</p><p class="s11">AuCo5</p></td><td><p class="s12">High corrosion resistance, low</p><p class="s12">tendency to material transfer</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg25Pt6</p></td><td><p class="s12">High corrosion resistance, low contact resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuAg26Ni3</p><p class="s11">AuAg25Cu5</p><p class="s11">AuAg20Cu10</p></td><td><p class="s12">Limited corrosion resistance</p></td><td><p class="s12">High hardness</p></td></tr><tr><td><p class="s11">AuPd40</p><p class="s11">AuPd35Ag10</p><p class="s11">AuCu14Pt9Ag4</p></td><td><p class="s12">High corrosion resistance</p></td><td><p class="s12">High hardness and mechanical</p><p class="s12">wear resistance</p></td></tr></table></figtable>

FigCaused by higher gold prices over the past years, the development of alloys with further reduced gold content had a high priority. 2The starting point has been the AuPd system, which has continuous solubility of the two components.8: Strain hardening Besides the binary alloy of AuPd40 and the ternary one AuPd35Ag9, other multiple component alloys were developed. These alloys typically have < 50 wt% Au by cold working[[File:Strain hardening of Au by cold workingand often can be solution hardened in order to obtain even higher hardness and tensile strength. They are mostly used in sliding contact applications.jpg|right|thumb|Strain hardening of Au by cold working]]

FigGold alloys are used in the form of welded wire or profile (also called weldtapes), segments, contact rivets and stampings produced from clad stripmaterials. 2.9: Softening The selection of Au after annealing the bonding process is based on the cost for 0.5 hrs after 80% cold working[[File:Softening the joining process and most importantly on the economical aspect of Au after annealing for 0.5 hrs.jpg|right|thumb|Softening using the least possible amount of Au after annealing for 0the expensive precious metal component.5 hrs after 80% cold working]]

Fig. 2.10: Strain hardening Besides being used as switching contacts in relays and pushbuttons, gold alloys are also applied in the design of AuPt10 by cold working[[Fileconnectors as well as sliding contacts for potentiometers, sensors, slip rings and brushes in miniature DC motors (<xr id="tab:Strain hardening Application Examples and Forms of AuPt10 by cold workingGold and Gold Alloys"/>)<!--(Table 2.5)-->.jpg|right|thumb|Strain hardening of AuPt10 by cold working]]

Fig. <figtable id="tab:Application Examples and Forms of Gold and Gold Alloys"><caption>'''<!--Table 2.115: Strain hardening -->Application Examples and Forms of AuAg20 by cold workingGold and Gold Alloys'''</caption>

Fig. 2.12: Strain hardening <table class="twocolortable"><tr><th><p class="s11">Material</p></th><th><p class="s12">Application Examples</p></th><th><p class="s12">Form of AuAg30 by cold workingApplication</p></th></tr><tr><td><p class="s11">Pure Gold</p><p class="s11">(electroplated)</p></td><td><p class="s12">Corrosion protection layer for contact parts, stationary contacts, bonding surfaces</p></td><td><p class="s12">Electroplated coatings, bond surface layers</p></td></tr><tr><td><p class="s11">Hard Gold</p><p class="s11">(sputtered)</p></td><td><p class="s12">Contact parts for connectors and switches, sliding contact tracks, bonding surfaces</p></td><td><p class="s12">Electroplated coatings on contact rivets and stamped parts</p></td></tr><tr><td><p class="s11">Hard Gold</p><p class="s11">(sputtered)</p></td><td><p class="s12">Contacts in switches and relays for low loads, electronic signal relays</p></td><td><p class="s12">Contact surface layer on miniature</p><p class="s12">profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuAg8</p></td><td><p class="s12">Dry circuit switching contacts, electronic</p><p class="s12">signal relays</p></td><td><p class="s12">Contact rivets, welded contact</p><p class="s12">parts</p></td></tr><tr><td><p class="s11">AuAg20</p></td><td><p class="s12">Switching contacts for low loads, electronic</p><p class="s12">signal relays</p></td><td><p class="s12">Contact rivets, welded contact</p><p class="s12">parts</p></td></tr><tr><td><p class="s11">AuAg25Cu5</p><p class="s11">AuAg25Cu10</p><p class="s11">AuAg26Ni3</p></td><td><p class="s12">Contact parts for connectors, switches and relays</p></td><td><p class="s12">Claddings on Cu alloys, contact rivets, contact layer on micro profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuNi5</p><p class="s11">AuCo5 (heterogen)</p></td><td><p class="s12">Contacts in switches and relays for low and medium loads, material transfer resistant contacts</p></td><td><p class="s12">Contact rivets, welded contact parts, contact layer on miniature profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuPt10</p><p class="s11">AuAg25Pt6</p></td><td><p class="s12">Contacts for highest chemical corrosion resistance in switches and relays</p></td><td><p class="s12">Contact rivets, contact layer on micro profiles (weld tapes)</p></td></tr><tr><td><p class="s11">AuCu14Pt9Ag4</p></td><td><p class="s12">Sliding contacts for measurement data transfer</p></td><td><p class="s12">Wire-formed parts</p></td></tr></table></figtable>

Fig. 2.14<div class="multiple-images"><figure id="fig:Phase diagram of goldplatinum">[[File: Softening Phase diagram of AuNi5 after annealing for 0goldplatinum.5 hrs after 80% cold workingjpg|left|thumb|<caption>Phase diagram of goldplatinum</caption>]]</figure>

Fig<figure id="fig:Phase diagram of gold-silver">[[File:Phase diagram of gold-silver. 2.15: Strain hardening jpg|left|thumb|<caption>Phase diagram of AuCo5 by cold workinggold-silver</caption>]]</figure>

Fig<figure id="fig:Phase diagram of gold-copper">[[File:Phase diagram of gold-copper. 2.16: Precipitation hardening jpg|left|thumb|<caption>Phase diagram of AuCo5 at 400°C hardening temperaturegold-copper</caption>]]</figure>

Fig<figure id="fig:Phase diagram of gold-nickel">[[File:Phase diagram of gold-nickel. 2.17: Strain hardening jpg|left|thumb|<caption>Phase diagram of AuAg25Pt6 by cold workinggold-nickel</caption>]]</figure>

Fig<figure id="fig:Phase diagram of gold-cobalt">[[File:Phase diagram of gold-cobalt. 2.18: Strain hardening jpg|left|thumb|<caption>Phase diagram of AuAg26Ni3 by cold workinggold-cobalt</caption>]]</figure>

Fig. 2.19<figure id="fig:Strain hardening of Au by cold working">[[File: Softening Strain hardening of AuAg26Ni3 after annealing for 0Au by cold working.5 hrs after 80% jpg|left|thumb|<caption>Strain hardening of Au by cold working</caption>]]</figure>

Fig<figure id="fig:Softening of Au after annealing for 0. 25 hrs">[[File:Softening of Au after annealing for 0.20: Strain hardening 5 hrs.jpg|left|thumb|<caption>Softening of AuAg25Cu5 by Au after annealing for 0.5 hrs after 80% cold working</caption>]]</figure>

Fig. 2<figure id="fig:Strain hardening of AuPt10 by cold working">[[File:Strain hardening of AuPt10 by cold working.21: jpg|left|thumb|<caption>Strain hardening of AuAg20Cu10 AuPt10 by cold working</caption>]]</figure>

Fig. 2.22<figure id="fig:Strain hardening of AuAg20 by cold working">[[File: Softening Strain hardening of AuAg20Cu10 after annealing for 0AuAg20 by cold working.5 hrs after 80% jpg|left|thumb|<caption>Strain hardening of AuAg20 by cold working</caption>]]</figure>

Fig. 2<figure id="fig:Strain hardening of AuAg30 by cold working">[[File:Strain hardening of AuAg30 by cold working.23: jpg|left|thumb|<caption>Strain hardening of AuCu14Pt9Ag4 AuAg30 by cold working</caption>]]</figure>

Fig. 2.24<figure id="fig:Strain hardening of AuNi5 by cold working">[[File: Precipitation Strain hardening of AuCu14Pt9Ag4 at different AuNi5 by cold working.jpg|left|thumb|<caption>Strain hardening temperatures after 50% of AuNi5 by cold working</caption>]]</figure>