Difference between revisions of "Precipitation Hardening Copper Alloys"

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(Other Precipitation Hardening Copper Alloys)
(5.1.6.2.2 Copper-Zirconium Alloys)
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Besides the naturally hard copper materials, precipitation hardening copper alloys play also an important role as carrier materials for electrical contacts. By means of a suitable heat treatment, finely dispersed precipitations of a second phase can be achieved, that increases the mechanical strength of these copper alloys significantly.  
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====5.1.6.1 Copper-Beryllium Alloys (Beryllium Bronze)====
  
====<!--5.1.6.1-->Copper-Beryllium Alloys (Beryllium Bronze)====
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The cause for precipitation hardening of CuBe materials is the rapidly diminishing solubility of beryllium in copper as temperature decrease. As the
 +
phase diagram for CuBe shows, 2.4 wt% of Be are soluble in Cu at 780°C <xr id="fig:Phase diagram of copperberyllium with temperature ranges for brazing and annealing treatments"/> (Fig. 5.28). In this temperature range annealed CuBe alloys are homogeneous(solution annealing). The homogeneous state can be frozen through rapid cooling to room temperature (quenching). Through a subsequent annealing at 325°C the desired precipitation hardening is achieved which results in a significant increase in mechanical strength and electrical conductivity of CuBe ''(Table 5.17)''. The final strength and hardness values depend on the annealing temperature and time as well as on the initial degree of cold working ''(Table 5.18)'' and [[#figures7|(Figs. 43 – 75)]](Figs. 5.29 - 5.31).
  
The cause for precipitation hardening of CuBe materials, is the rapidly diminishing solubility of beryllium in copper as temperature decreases. As the
+
<figure id="fig:Phase diagram of copperberyllium with temperature ranges for brazing and annealing treatments">
phase diagram for CuBe shows, 2.4 wt% of Be are soluble in Cu at 780°C (<xr id="fig:Phase_diagram_of_copperberyllium_with_temperature_ranges_for_brazing_and_annealing_treatments"/><!--(Fig. 5.28)-->). In this temperature range, annealed CuBe alloys are homogeneous(solution annealing). The homogeneous state can be frozen through rapid cooling to room temperature (quenching). Through a subsequent annealing at 325°C, the desired precipitation hardening is achieved, which results in a significant increase in mechanical strength and electrical conductivity of CuBe (<xr id="tab:Physical_Properties_of_Selected_Copper_Beryllium_Alloys"/><!--(Tab. 5.17)-->). The final strength and hardness values depend on the annealing temperature and time, as well as on the initial degree of cold working (<xr id="tab:Mechanical Properties of Selected Copper-Beryllium Alloys"/><!--(Table 5.18)--> and <xr id="fig:Precipitation_hardening_of_CuBe2_at_325°C_after_different_cold_working"/>, <xr id="fig:Precipitation_hardening_of_CuBe2_(soft)_at_325°C"/>, <xr id="fig:Precipitation_hardening_of_CuBe2_(half hard)_at_different_annealing_temperatures"/>).
+
Fig. 5.28: Phase diagram of copperberyllium with temperature ranges for brazing and annealing treatments
 +
[[File:Phase diagram of copper beryllium with temperature ranges.jpg|right|thumb|Phase diagram of copper- beryllium with temperature ranges for brazing and annealing treatments]]
 +
</figure>
  
 +
As precipitation hardening alloys CuBe materials, mainly CuBe2 and CuBe1.7 have gained broad usage as current carrying contact springs because of their outstanding mechanical properties. Besides these CuCo2Be and CuNi2Be, which have medium mechanical strength and a relatively high electrical
 +
conductivity, are also used as contact carrier materials. After stamping and forming into desired contact configurations these CuBe materials are then precipitation hardened. CuBe alloys are available as semi-finished materials in a variety of cold work conditions. They can also be supplied and used in the already precipitation hardened condition without significant strength losses. In this case the hardening was already performed at the alloy producer.
  
As precipitation hardening alloys CuBe materials, mainly CuBe2 and CuBe1.7 have gained broad usage as current carrying contact springs because of their outstanding mechanical properties. Besides these, CuCo2Be and CuNi2Be, which have medium mechanical strength and a relatively high electrical
+
Since Beryllium is rated as a carcinogen by the European regulation EU-67/548, it has been tried to reach the application properties of the well established CuBe1.7 and CuBe2 alloys with a lower Be content. The development efforts for alternate precipitation hardening materials without toxic and declaration requiring additive materials, for example CuNiCoSi, are aimed at the replacement of CuBe.
conductivity, are also used as contact carrier materials. After stamping and forming into desired contact configurations, these CuBe materials are then precipitation hardened. CuBe alloys are available as semi-finished materials in a variety of cold work conditions. They can also be supplied and used in the already precipitation hardened condition, without significant strength losses. In this case, the hardening was already performed at the alloy producer.
 
  
Since Beryllium is rated as a carcinogen by the European regulation EU-67/548, it has been tried to reach the application properties of the well established CuBe1.7 and CuBe2 alloys with a lower Be content. Development efforts for alternative precipitation hardening materials without toxic and declarable additives are underway, e.g. CuNiCoSi as a substitute for CuBe.
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<div id="figures7">
 +
<xr id="fig:Precipitation hardening of CuBe2 at 325°C after different cold working"/> Fig. 5.29: Precipitation hardening of CuBe2 at 325°C after different cold working
  
<div class="multiple-images">
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<xr id="fig:Precipitation hardening of CuBe2 (soft) at 325°C"/> Fig. 5.30: Precipitation hardening of CuBe2 (soft) at 325°C
  
<figure id="fig:Phase_diagram_of_copperberyllium_with_temperature_ranges_for_brazing_and_annealing_treatments">
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<xr id="fig:Precipitation hardening of CuBe2 (half hard) at different annealing temperatures"/> Fig. 5.31: Precipitation hardening of CuBe2 (half hard) at different annealing temperatures
[[File:Phase diagram of copper beryllium with temperature ranges.jpg|left|thumb|<caption>Phase diagram of copper- beryllium with temperature ranges for brazing and annealing treatments</caption>]]
+
</div>
</figure>
 
  
<figure id="fig:Precipitation_hardening_of_CuBe2_at_325°C_after_different_cold_working">  
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<div class="multiple-images">
[[File:Precipitation hardening of CuBe2 at 325C.jpg|left|thumb|<caption>Precipitation hardening of CuBe2 at 325°C after different cold working</caption>]]
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<figure id="fig:Precipitation hardening of CuBe2 at 325°C after different cold working">  
 +
[[File:Precipitation hardening of CuBe2 at 325C.jpg|right|thumb|Precipitation hardening of CuBe2 at 325°C after different cold working]]
 
</figure>
 
</figure>
  
<figure id="fig:Precipitation_hardening_of_CuBe2_(soft)_at_325°C">  
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<figure id="fig:Precipitation hardening of CuBe2 (soft) at 325°C">  
[[File:Precipitation hardening of CuBe2 (soft) at 325C.jpg|left|thumb|<caption>Precipitation hardening of CuBe2 (soft) at 325°C</caption>]]
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[[File:Precipitation hardening of CuBe2 (soft) at 325C.jpg|right|thumb|Precipitation hardening of CuBe2 (soft) at 325°C]]
 
</figure>
 
</figure>
  
<figure id="fig:Precipitation_hardening_of_CuBe2_(half hard)_at_different_annealing_temperatures">  
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<figure id="fig:Precipitation hardening of CuBe2 (half hard) at different annealing temperatures">  
[[File:Precipitation hardening of CuBe2 half hard.jpg|left|thumb|<caption>Precipitation hardening of CuBe2 (half hard) at different annealing temperatures</caption>]]
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[[File:Precipitation hardening of CuBe2 half hard.jpg|right|thumb|Precipitation hardening of CuBe2 (half hard) at different annealing temperatures]]
 
</figure>
 
</figure>
 
</div>
 
</div>
 
<div class="clear"></div>
 
<div class="clear"></div>
  
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'''Table 5.17: Physical Properties of Selected Copper-Beryllium Alloys''' (2 Teile!)
  
<figtable id="tab:Physical_Properties_of_Selected_Copper_Beryllium_Alloys">
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'''Table 5.18: Mechanical Properties of Selected Copper-Beryllium Alloys''' (2 Teile!)
<caption>'''<!--Table 5.17:-->Physical Properties of Selected Copper-Beryllium Alloys'''</caption> 
 
  
{| class="twocolortable" style="text-align: left; font-size: 12px"
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====5.1.6.2 Other Precipitation Hardening Copper Alloys====
|-
 
!Material<br />Designation<br />EN UNS
 
!Composition<br />[wt%]
 
!Density<br />[g/cm<sup>3</sup>]
 
!colspan="2" style="text-align:center"|Electrical<br />Conductivity
 
!Electrical<br />Resistivity<br />[μΩ·cm]
 
!Thermal<br />Conductivity<br />[W/(m·K)]
 
!Coeff. of Linear<br />Thermal<br />Expansion<br />[10<sup>-6</sup>/K]
 
!Modulus of<br />Elasticity<br />[GPa]
 
!Softening Temperature<br />(approx. 10% loss in<br />strength)<br />[°C]
 
!Melting<br />Temp Range<br />[°C]
 
|-
 
!
 
!
 
!
 
![MS/m] 
 
![% IACS]
 
!
 
!
 
!
 
!
 
!
 
!
 
|-
 
|CuBe1.7<br />CW100C<br />C17000
 
|Be 1.6 - 1.8<br />Co 0.3<br />Ni 0.3<br />Cu Rest
 
|8.4
 
|8 - 9[[#text-reference1|<sup>a</sup>]]<br />12 - 13[[#text-reference2|<sup>b</sup>]]<br />11[[#text-reference3|<sup>c</sup>]]
 
|14 - 16<br />21 - 22<br />19
 
|11 - 12.5[[#text-reference1|<sup>a</sup>]]<br />7.7 - 8.3[[#text-reference2|<sup>b</sup>]]9.1[[#text-reference3|<sup>c</sup>]]
 
|110
 
|17
 
|125[[#text-reference1|<sup>a</sup>]]<br />[[#text-reference2|<sup>b</sup>]]
 
|ca. 380
 
|890 - 1000
 
|-
 
|CuBe2<br />CW101C<br />C17200
 
|Be 1.8 - 2.1<br />Co 0.3<br />Ni 0.3<br />Cu Rest
 
|8.3
 
|8 - 9[[#text-reference1|<sup>a</sup>]]<br />12 - 13[[#text-reference2|<sup>b</sup>]]<br />11[[#text-reference3|<sup>c</sup>]]
 
|14 - 16<br />21 - 22<br />19
 
|11 - 12.5[[#text-reference1|<sup>a</sup>]]<br />7.7 - 8.3[[#text-reference2|<sup>b</sup>]]<br />9.1[[#text-reference3|<sup>c</sup>]]
 
|110
 
|17
 
|125[[#text-reference1|<sup>a</sup>]]<br />135[[#text-reference2|<sup>b</sup>]]
 
|ca. 380
 
|870 - 980
 
|-
 
|CuCo2Be<br />CW104C<br />C17500
 
|Co 2.0 - 2.8<br />Be 0.4 - 0.7<br />Ni 0.3<br />Cu Rest
 
|8.8
 
|11 - 14[[#text-reference1|<sup>a</sup>]]<br />25 - 27[[#text-reference2|<sup>b</sup>]]<br />27 - 34[[#text-reference3|<sup>c</sup>]]
 
|19 - 24<br />43 - 47<br />47 - 59
 
|7.1 - 9.1[[#text-reference1|<sup>a</sup>]]<br />3.7 - 4.0[[#text-reference2|<sup>b</sup>]]<br />2.9[[#text-reference3|<sup>c</sup>]]
 
|210
 
|18
 
|131[[#text-reference1|<sup>a</sup>]]<br />138[[#text-reference2|<sup>b</sup>]]
 
|ca. 450
 
|1030 - 1070
 
|-
 
|CuNi2Be<br />CW110C<br />C17510
 
|Ni 1.4 - 2.2<br />Be 0.2 - 0.6<br />Co 0.3<br />Cu Rest
 
|8.8
 
|11 - 14[[#text-reference1|<sup>a</sup>]]<br />25 - 27[[#text-reference2|<sup>b</sup>]]<br />27 - 34[[#text-reference3|<sup>c</sup>]]
 
|19 - 24<br />43 - 47<br />47 - 59
 
|7.1 - 9.1[[#text-reference1|<sup>a</sup>]]<br />3.7 - 4.0[[#text-reference2|<sup>b</sup>]]<br />2.9[[#text-reference3|<sup>c</sup>]]
 
|230
 
|18
 
|131[[#text-reference1|<sup>a</sup>]]<br />138[[#text-reference2|<sup>b</sup>]]
 
|ca. 480
 
|1060 - 1100
 
|}
 
<div id="text-reference1"><sub>a</sub> solution annealed, and cold rolled</div>
 
<div id="text-reference2"><sub>b</sub> solution annealed, cold rolled, and precipitation hardened</div>
 
<div id="text-reference3"><sub>c</sub> solution annealed, cold rolled, and precipitation hardened at mill (mill hardened)</div>
 
</figtable>
 
<br/>
 
<br/>
 
  
<figtable id="tab:Mechanical Properties of Selected Copper-Beryllium Alloys">
+
=====5.1.6.2.1 Copper-Chromium Alloys=====
<caption>'''<!--Table 5.18:-->Mechanical Properties of Selected Copper-Beryllium Alloys'''</caption> 
 
  
{| class="twocolortable" style="text-align: left; font-size: 12px"
+
As the phase diagram shows, copper-chromium has a similar hardening profile compared to CuBe <xr id="fig:Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium"/>(Fig. 5.32). In the hardened stage CuCr has limitations to work hardening. Compared to copper it has a better temperature stability with good electrical conductivity. Hardness and electrical conductivity as a function of cold working and precipitation hardening conditions are illustrated in [[#figures8|(Figs. 6 – 9)]] Figs. 5.33-5.35, <xr id="tab:tab5.19"/> (Tables 5.19) and <xr id="tab:tab5.20"/> (Tab. 5.20).
|-
 
!Material
 
!Hardness<br />Condition
 
!Tensile Strength R<sub>m</sub><br />[MPa]
 
!0,2% Yield Strength<br />R<sub>p02</sub><br />[MPa]
 
!Elongation<br />A<sub>50</sub><br />[%]
 
!Vickers<br />Hardness<br />HV
 
!Bend Radius[[#text-reference4|<sup>1</sup>]]<br />perpendicular to<br />rolling direction
 
!Bend Radius[[#text-reference4|<sup>1</sup>]]<br />parallel to<br />rolling direction
 
!Spring Bending<br />Limit σ<sub>FB</sub><br />[MPa]
 
!Spring Fatigue<br />Limit σ<sub>BW</sub><br />[MPa]
 
|-
 
|CuBe1,7
 
|R 390[[#text-reference5|<sup>a</sup>]]<br />R 680[[#text-reference5|<sup>a</sup>]]<br />R 1030[[#text-reference6|<sup>b</sup>]]<br />R 1240[[#text-reference6|<sup>b</sup>]]<br />R 680[[#text-reference7|<sup>c</sup>]]<br />R 1100[[#text-reference7|<sup>c</sup>]]
 
|380 -520<br />680 - 820<br />1030 - 1240<br />1240 - 1380<br />680 - 750<br />1100 - 1200
 
|&ge; 180<br />&ge; 600<br />&ge; 900<br />&ge; 1070<br />&ge; 480<br />&ge; 930
 
|35<br />2<br />3<br />1<br />18<br />3
 
|80 - 135<br />210 - 250<br />330 - 380<br />360 - 420<br />220 - 350<br />330 - 370
 
|0 x t<br />1 x t<br />1 x t<br /><br />1 x t<br />6 x t
 
|0 x t<br />3 x t<br />1.5 x t<br /><br />1 x t<br />10 x t
 
| <br /> <br />700<br />1000<br />390<br />790
 
| <br /> <br />260<br />280<br /> <br />260
 
|-
 
|CuBe2
 
|R 410[[#text-reference5|<sup>a</sup>]]<br />R 690[[#text-reference5|<sup>a</sup>]]<br />R 1140[[#text-reference6|<sup>b</sup>]]<br />R 1310[[#text-reference6|<sup>b</sup>]]<br />R 690[[#text-reference7|<sup>c</sup>]]<br />R 1200[[#text-reference7|<sup>c</sup>]]
 
|410 -540<br />690 - 820<br />1140 - 1310<br />1310 - 1480<br />690 - 760<br />1200 - 1320
 
|&ge; 190<br />&ge; 650<br />&ge; 1000<br />&ge; 1150<br />&ge; 480<br />&ge; 1030
 
|35<br />2<br />3<br />1<br />18<br />3
 
|90 - 140<br />215 - 260<br />350 - 400<br />380 - 450<br />220 - 250<br />360 - 410
 
|0 x t<br />1 x t<br /> <br /> <br />1 x t<br />5 x t
 
|0 x t<br />3 x t<br /> <br /> <br />1.5 x t<br />10 x t
 
| <br /> <br />800<br />1040<br />400<br />900
 
| <br /> <br />270<br />300<br /> <br />280
 
|-
 
|CuCo2Be<br />CuNi2Be
 
|R 250[[#text-reference5|<sup>a</sup>]]<br />R 550[[#text-reference5|<sup>a</sup>]]<br />R 650[[#text-reference6|<sup>b</sup>]]<br />R 850[[#text-reference6|<sup>b</sup>]]<br />R 520[[#text-reference7|<sup>c</sup>]]
 
|250 - 380<br />550 - 700<br />650 - 820<br />850 - 1000<br />520 - 620
 
|&ge; 140<br />&ge; 450<br />&ge; 520<br />&ge; 750<br />&ge; 340
 
|20<br />2<br />10<br />1<br />5
 
|60 - 90<br />160 - 200<br />195 - 230<br />240 - 290<br />150 - 180
 
|0 x t<br />3 x t<br />1 x t<br />3 x t<br />1 x t
 
|0 x t<br /> <br />1 x t<br />3.5 x t<br />1 x t
 
| <br /> <br />360<br />650<br />300
 
| <br /> <br />220<br />250<br />210
 
|}
 
<div id="text-reference4"><sub>1</sub> t: Strip thickness max. 0.5 mm</div>
 
<div id="text-reference5"><sub>a</sub> solution annealed, and cold rolled</div>
 
<div id="text-reference6"><sub>b</sub> solution annealed, cold rolled, and precipitation hardened</div>
 
<div id="text-reference7"><sub>c</sub> solution annealed, cold rolled, and precipitation hardened at mill (mill hardened)</div>
 
</figtable>
 
<br/>
 
<br/>
 
  
====<!--5.1.6.2-->Other Precipitation Hardening Copper Alloys====
+
Copper-chromium materials are especially suitable for use as electrodes for resistance welding. During brazing the loss in hardness is limited if low melting brazing alloys and reasonably short heating times are used.
  
=====<!--5.1.6.2.1-->Copper-Chromium Alloys=====
+
<figure id="fig:Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium">
 +
Fig. 5.32: Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium
 +
[[File:Copper corner of the copper chromium phase diagram.jpg|right|thumb|Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium]]
 +
</figure>
  
As the phase diagram shows, copper-chromium has a similar hardening profile compared to CuBe (<xr id="fig:Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium"/><!--(Fig. 5.32)-->). In the hardened stage CuCr has limitations to work hardening. Compared to copper it has a better temperature stability with good electrical conductivity. Hardness and electrical conductivity as a function of cold working and precipitation hardening conditions are illustrated in [[#figures8|(Figs. 6 – 9]]<!--Figs. 5.33-5.35--> and <xr id="tab:Physical Properties of Other Precipitation Hardening Copper Alloys"/><!--(Tables 5.19)--> and <xr id="tab:Mechanical Properties of Other Precipitation Hardening Copper Alloys"/><!--(Tab. 5.20)-->).
+
<div id="figures5">
 +
<xr id="fig:Softening of precipitation hardened and subsequently cold worked CuCr1"/> Fig. 5.33: Softening of precipitation-hardened and subsequently cold worked CuCr1 after 4hrs annealing
  
Copper-chromium materials are especially suitable for use as electrodes for resistance welding. During brazing the loss in hardness is limited, if low melting brazing alloys and reasonably short heating times are used.
+
<xr id="fig:Electrical conductivity of precipitation hardened CuCr 0.6"/> Fig. 5.34 a: Electrical conductivity of precipitation hardened CuCr 0.6 as a function of annealing conditions
  
<div class="multiple-images">
+
<xr id="fig:Hardness of precipitation hardened CuCr 0.6"/> Fig. 5.34 b: Hardness of precipitation hardened CuCr 0.6 as a function of annealing conditions
  
<figure id="fig:Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium">
+
<xr id="fig:Electrical conductivity and hardness of precipitation hardened CuCr 0.6"/> Fig. 5.35: Electrical conductivity and hardness of precipitation hardened CuCr 0.6 after cold working
[[File:Copper corner of the copper chromium phase diagram.jpg|left|thumb|<caption>Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium</caption>]]
+
</div>
</figure>
 
  
 +
<div class="multiple-images">
 
<figure id="fig:Softening of precipitation hardened and subsequently cold worked CuCr1">  
 
<figure id="fig:Softening of precipitation hardened and subsequently cold worked CuCr1">  
[[File:Softening of precipitation hardened and subsequently cold worked CuCr1.jpg|left|thumb|<caption>Softening of precipitation-hardened and subsequently cold worked CuCr1 after 4hrs annealing</caption>]]
+
[[File:Softening of precipitation hardened and subsequently cold worked CuCr1.jpg|right|thumb|Softening of precipitation-hardened and subsequently cold worked CuCr1 after 4hrs annealing]]
 
</figure>
 
</figure>
  
 
<figure id="fig:Electrical conductivity of precipitation hardened CuCr 0.6">  
 
<figure id="fig:Electrical conductivity of precipitation hardened CuCr 0.6">  
[[File:Electrical conductivity of precipitation hardened CuCr 0.6.jpg|left|thumb|<caption>Electrical conductivity of precipitation hardened CuCr 0.6 as a function of annealing conditions</caption>]]
+
[[File:Electrical conductivity of precipitation hardened CuCr 0.6.jpg|right|thumb|Electrical conductivity of precipitation hardened CuCr 0.6 as a function of annealing conditions]]
 
</figure>
 
</figure>
  
 
<figure id="fig:Hardness of precipitation hardened CuCr 0.6">  
 
<figure id="fig:Hardness of precipitation hardened CuCr 0.6">  
[[File:Hardness of precipitation hardened CuCr 0.6.jpg|left|thumb|<caption>Hardness of precipitation hardened CuCr 0.6 as a function of annealing conditions</caption>]]
+
[[File:Hardness of precipitation hardened CuCr 0.6.jpg|right|thumb|Hardness of precipitation hardened CuCr 0.6 as a function of annealing conditions]]
 
</figure>
 
</figure>
  
 
<figure id="fig:Electrical conductivity and hardness of precipitation hardened CuCr 0.6">   
 
<figure id="fig:Electrical conductivity and hardness of precipitation hardened CuCr 0.6">   
[[File:Electrical conductivity and hardness of precipitation hardened CuCr 0.6.jpg|left|thumb|<caption>Electrical conductivity and hardness of precipitation hardened CuCr 0.6 after cold working</caption>]]
+
[[File:Electrical conductivity and hardness of precipitation hardened CuCr 0.6.jpg|right|thumb|Electrical conductivity and hardness of precipitation hardened CuCr 0.6 after cold working]]
 
</figure>
 
</figure>
 
</div>
 
</div>
Line 206: Line 84:
  
  
<figtable id="tab:Physical Properties of Other Precipitation Hardening Copper Alloys">
+
'''Table 5.19: Physical Properties of Other Precipitation Hardening Copper Alloys''' (2 Teile!)
<caption>'''<!--Table 5.19:-->Physical Properties of Other Precipitation Hardening Copper Alloys'''</caption> 
 
  
{| class="twocolortable" style="text-align: left; font-size: 12px"
+
<figtable id="tab:tab5.20">
|-
+
'''Table 5.20: Mechanical Properties of Other Precipitation Hardening Copper Alloys'''
!Material<br />Designation<br />EN UNS
+
 
!Composition<br />[wt%]
+
<table border="1" cellspacing="0" style="border-collapse:collapse"><tr><td><p class="s16">Material</p></td><td><p class="s16">Hardness</p><p class="s16">Condi- tion</p></td><td><p class="s16">Tensile</p><p class="s16">Strength R<span class="s18">m</span></p><p class="s16">[MPa]</p></td><td><p class="s16">0,2% Yield</p><p class="s16">Strength R<span class="s18">p02</span></p><p class="s16">[MPa]</p></td><td><p class="s16">Elongation</p><p class="s16">A50</p><p class="s16">[%]</p></td><td><p class="s16">Vickers</p><p class="s16">Hardness</p><p class="s16">HV</p></td><td><p class="s16">Spring Bending</p><p class="s16">Limit <span class="s19">F</span><span class="s18">FB </span>[MPa]</p></td></tr><tr><td><p class="s16">CuCr</p></td><td><p class="s16">R 230<span class="s18">a</span></p><p class="s16">R 400<span class="s18">a </span>R 450<span class="s18">b </span>R 550<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 230</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 450</span></p><p class="s33">&gt;<span class="s16"> 550</span></p></td><td><p class="s33">&gt;<span class="s16"> 80</span></p><p class="s33">&gt;<span class="s16"> 295</span></p><p class="s33">&gt;<span class="s16"> 325</span></p><p class="s33">&gt;<span class="s16"> 440</span></p></td><td><p class="s16">30</p><p class="s16">10</p><p class="s16">10</p><p class="s16">8</p></td><td><p class="s33">&gt;<span class="s16"> 55</span></p><p class="s33">&gt;<span class="s16"> 120</span></p><p class="s33">&gt;<span class="s16"> 130</span></p><p class="s33">&gt;<span class="s16"> 150</span></p></td><td><p class="s16">350</p></td></tr><tr><td><p class="s16">CuZr</p></td><td><p class="s16">R 260<span class="s18">a</span></p><p class="s16">R 370<span class="s18">a </span>R 400<span class="s18">b </span>R 420<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 260</span></p><p class="s33">&gt;<span class="s16"> 370</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 420</span></p></td><td><p class="s33">&gt;<span class="s16"> 100</span></p><p class="s33">&gt;<span class="s16"> 270</span></p><p class="s33">&gt;<span class="s16"> 280</span></p><p class="s33">&gt;<span class="s16"> 400</span></p></td><td><p class="s16">35</p><p class="s16">12</p><p class="s16">12</p><p class="s16">10</p></td><td><p class="s33">&gt;<span class="s16"> 55</span></p><p class="s33">&gt;<span class="s16"> 100</span></p><p class="s33">&gt;<span class="s16"> 105</span></p><p class="s33">&gt;<span class="s16"> 115</span></p></td><td><p class="s16">280</p></td></tr><tr><td><p class="s16">CuCr1Zr</p></td><td><p class="s16">R 200<span class="s18">a</span></p><p class="s16">R 400<span class="s18">b</span></p><p class="s16">R 450<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 200</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 450</span></p></td><td><p class="s33">&gt;<span class="s16"> 60</span></p><p class="s33">&gt;<span class="s16"> 210</span></p><p class="s33">&gt;<span class="s16"> 360</span></p></td><td><p class="s16">30</p><p class="s16">12</p><p class="s16">10</p></td><td><p class="s33">&gt;<span class="s16"> 70</span></p><p class="s33">&gt;<span class="s16"> 140</span></p><p class="s33">&gt;<span class="s16"> 155</span></p></td><td><p class="s16">420</p></td></tr></table>
!Density<br />[g/cm<sup>3</sup>]
 
!colspan="2" style="text-align:center"|Electrical<br />Conductivity
 
!Electrical<br />Resistivity<br />[μΩ·cm]
 
!Thermal<br />Conductivity<br />[W/(m·K)]
 
!Coeff. of Linear<br />Thermal<br />Expansion<br />[10<sup>-6</sup>/K]
 
!Modulus of<br />Elasticity<br />[GPa]
 
!Softening Temperature<br />(approx. 10% loss in<br />strength)<br />[°C]
 
!Melting<br />Temp Range<br />[°C]
 
|-
 
!
 
!
 
!
 
![MS/m] 
 
![% IACS]
 
!
 
!
 
!
 
!
 
!
 
!
 
|-
 
|CuCr
 
|Cr 0.3 - 1.2<br />Cu Rest
 
|8.89
 
|26[[#text-reference8|<sup>a</sup>]]<br />48[[#text-reference9|<sup>b</sup>]]
 
|45[[#text-reference8|<sup>a</sup>]]<br />83[[#text-reference9|<sup>b</sup>]]
 
|3.8[[#text-reference8|<sup>a</sup>]]<br />2.1[[#text-reference9|<sup>b</sup>]]
 
|170[[#text-reference8|<sup>a</sup>]]<br />315[[#text-reference9|<sup>b</sup>]]
 
|17
 
|112
 
|ca. 450
 
|980 - 1080
 
|-
 
|CuZr
 
|Zr 0.1 - 0.3<br />Cu Rest
 
|8.9
 
|35[[#text-reference8|<sup>a</sup>]]<br />52[[#text-reference9|<sup>b</sup>]]
 
|60[[#text-reference8|<sup>a</sup>]]<br />90[[#text-reference9|<sup>b</sup>]]
 
|2.9[[#text-reference8|<sup>a</sup>]]<br />1.9[[#text-reference9|<sup>b</sup>]]
 
|340[[#text-reference8|<sup>a</sup>]]
 
|16
 
|135
 
|ca. 500
 
|1020 - 1080
 
|-
 
|CuCr1Zr<br />CW106C<br />C18150
 
|Cr 0.5 - 1.2<br />Zr 0.03 - 0.3<br />Cu Rest
 
|8.92
 
|20[[#text-reference8|<sup>a</sup>]]<br />43[[#text-reference9|<sup>b</sup>]]
 
|34[[#text-reference8|<sup>a</sup>]]<br />74[[#text-reference9|<sup>b</sup>]]
 
|5.0[[#text-reference8|<sup>a</sup>]]<br />2.3[[#text-reference9|<sup>b</sup>]]
 
|170[[#text-reference8|<sup>a</sup>]]<br />310 - 330[[#text-reference9|<sup>b</sup>]]
 
|16
 
|110[[#text-reference8|<sup>a</sup>]]<br />130[[#text-reference9|<sup>b</sup>]]
 
|ca. 500
 
|1070 - 1080
 
|}
 
<div id="text-reference8"><sub>a</sub> solution annealed, and cold rolled</div>
 
<div id="text-reference9"><sub>b</sub> solution annealed, cold rolled, and precipitation hardened</div>
 
 
</figtable>
 
</figtable>
<br />
 
<br />
 
  
<figtable id="tab:Mechanical Properties of Other Precipitation Hardening Copper Alloys">
+
=====5.1.6.2.2 Copper-Zirconium Alloys=====
<caption>'''<!--Table 5.20:-->Mechanical Properties of Other Precipitation Hardening Copper Alloys'''</caption>
 
  
<table class="twocolortable">
+
The solubility of Zirconium in copper is 0.15 wt% Zr at the eutectic temperature of 980°C <xr id="fig:Copper corner of the copper zirconium for up to 0.5-wt zirconium"/> (Fig. 5.36). Copper-zirconium materials have a similar properties spectrum compared to the one for copper-chromium materials. At room temperature the mechanical properties of copper-zirconium are less suitable than those of copper chromium, its temperature stability is however at least the same.
<tr><th><p class="s16">Material</p></th><th><p class="s16">Hardness</p><p class="s16">Condi- tion</p></th><th><p class="s16">Tensile</p><p class="s16">Strength R<span class="s18">m</span></p><p class="s16">[MPa]</p></th><th><p class="s16">0,2% Yield</p><p class="s16">Strength R<span class="s18">p02</span></p><p class="s16">[MPa]</p></th><th><p class="s16">Elongation</p><p class="s16">A50</p><p class="s16">[%]</p></th><th><p class="s16">Vickers</p><p class="s16">Hardness</p><p class="s16">HV</p></th><th><p class="s16">Spring Bending</p><p class="s16">Limit <span class="s19">F</span><span class="s18">FB </span>[MPa]</p></th></tr><tr><td><p class="s16">CuCr</p></td><td><p class="s16">R 230<span class="s18">a</span></p><p class="s16">R 400<span class="s18">a </span>R 450<span class="s18">b </span>R 550<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 230</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 450</span></p><p class="s33">&gt;<span class="s16"> 550</span></p></td><td><p class="s33">&gt;<span class="s16"> 80</span></p><p class="s33">&gt;<span class="s16"> 295</span></p><p class="s33">&gt;<span class="s16"> 325</span></p><p class="s33">&gt;<span class="s16"> 440</span></p></td><td><p class="s16">30</p><p class="s16">10</p><p class="s16">10</p><p class="s16">8</p></td><td><p class="s33">&gt;<span class="s16"> 55</span></p><p class="s33">&gt;<span class="s16"> 120</span></p><p class="s33">&gt;<span class="s16"> 130</span></p><p class="s33">&gt;<span class="s16"> 150</span></p></td><td><p class="s16">350</p></td></tr><tr><td><p class="s16">CuZr</p></td><td><p class="s16">R 260<span class="s18">a</span></p><p class="s16">R 370<span class="s18">a </span>R 400<span class="s18">b </span>R 420<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 260</span></p><p class="s33">&gt;<span class="s16"> 370</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 420</span></p></td><td><p class="s33">&gt;<span class="s16"> 100</span></p><p class="s33">&gt;<span class="s16"> 270</span></p><p class="s33">&gt;<span class="s16"> 280</span></p><p class="s33">&gt;<span class="s16"> 400</span></p></td><td><p class="s16">35</p><p class="s16">12</p><p class="s16">12</p><p class="s16">10</p></td><td><p class="s33">&gt;<span class="s16"> 55</span></p><p class="s33">&gt;<span class="s16"> 100</span></p><p class="s33">&gt;<span class="s16"> 105</span></p><p class="s33">&gt;<span class="s16"> 115</span></p></td><td><p class="s16">280</p></td></tr><tr><td><p class="s16">CuCr1Zr</p></td><td><p class="s16">R 200<span class="s18">a</span></p><p class="s16">R 400<span class="s18">b</span></p><p class="s16">R 450<span class="s18">b</span></p></td><td><p class="s33">&gt;<span class="s16"> 200</span></p><p class="s33">&gt;<span class="s16"> 400</span></p><p class="s33">&gt;<span class="s16"> 450</span></p></td><td><p class="s33">&gt;<span class="s16"> 60</span></p><p class="s33">&gt;<span class="s16"> 210</span></p><p class="s33">&gt;<span class="s16"> 360</span></p></td><td><p class="s16">30</p><p class="s16">12</p><p class="s16">10</p></td><td><p class="s33">&gt;<span class="s16"> 70</span></p><p class="s33">&gt;<span class="s16"> 140</span></p><p class="s33">&gt;<span class="s16"> 155</span></p></td><td><p class="s16">420</p></td></tr></table>
 
</figtable>
 
  
=====<!--5.1.6.2.2-->Copper-Zirconium Alloys=====
+
<figure id="fig:Copper corner of the copper zirconium for up to 0.5-wt zirconium">
 +
[[File:Copper corner of the copper zirconium for up to 0.5-wt zirconium.jpg|right|thumb|Copper corner of the copper- zirconium for up to 0.5 wt% zirconium]]
 +
</figure>
  
The solubility of Zirconium in copper is 0.15 wt% Zr at the eutectic temperature of 980°C (<xr id="fig:Copper corner of the copper zirconium for up to 0.5-wt zirconium"/><!--(Fig. 5.36)-->). Copper-zirconium materials have a similar properties spectrum, compared to the one for copper-chromium materials. At room temperature the mechanical properties of copper-zirconium are less suitable than those of copper chromium, its temperature stability is however at least the same.
+
=====5.1.6.2.3 Copper-Chromium-Zirconium Alloys=====
  
=====<!--5.1.6.2.3-->Copper-Chromium-Zirconium Alloys=====
+
The earlier used CuCr and CuZr materials have been partially replaced over the years by the capitation hardening three materials alloy CuCr1Zr. This material exhibits high mechanical strength at elevated temperatures and good oxidation resistance as well as high softening temperatures. In its hardened condition CuCr1Zr has also a high electrical conductivity (Bild 5.37). Their usage extends from mechanically and thermally highly stressed parts such as contact tulips in high voltage switchgear to electrodes for resistance welding.
  
The earlier used CuCr and CuZr materials have been partially replaced over the years, by the capitation hardening three materials alloy CuCr1Zr. This material exhibits high mechanical strength at elevated temperatures and good oxidation resistance as well as high softening temperatures. In its hardened condition CuCr1Zr has also a high electrical conductivity (<xr id="fig:Softening of CuCr1Zr after 1hr annealing"/><!--(Bild 5.37)-->). Their usage extends from mechanically and thermally highly stressed parts, such as contact tulips in high voltage switchgear or electrodes for resistance welding.
+
Fig. 5.36: Copper corner of the copperzirconium for up to 0.5 wt% zirconium
 
+
[[File:Copper corner of the copper zirconium for up to 0.5-wt zirconium.jpg|right|thumb|Copper corner of the copper- zirconium for up to 0.5 wt% zirconium]]  
<div class="multiple-images">
 
<figure id="fig:Copper corner of the copper zirconium for up to 0.5-wt zirconium">
 
[[File:Copper corner of the copper zirconium for up to 0.5-wt zirconium.jpg|right|thumb|Figure 10: Copper corner of the copper- zirconium for up to 0.5 wt% zirconium]]  
 
</figure>
 
  
<figure id="fig:Softening of CuCr1Zr after 1hr annealing">
+
Fig. 5.37: Softening of CuCr1Zr after 1 hr annealing and after 90% cold working
[[File:Softening of CuCr1Zr after 1hr annealing.jpg|right|thumb|Figure 11: Softening of CuCr1Zr after 1 hr annealing and after 90% cold working]]
+
[[File:Softening of CuCr1Zr after 1hr annealing.jpg|right|thumb|Softening of CuCr1Zr after 1 hr annealing and after 90% cold working]]
</figure>
 
</div>
 
<div class="clear"></div>
 
  
 
==References==
 
==References==
 
[[Contact Carrier Materials#References|References]]
 
[[Contact Carrier Materials#References|References]]
 
[[de:Aushärtbare_Kupfer-Legierungen]]
 

Revision as of 11:21, 11 March 2014

5.1.6.1 Copper-Beryllium Alloys (Beryllium Bronze)

The cause for precipitation hardening of CuBe materials is the rapidly diminishing solubility of beryllium in copper as temperature decrease. As the phase diagram for CuBe shows, 2.4 wt% of Be are soluble in Cu at 780°C Figure 1 (Fig. 5.28). In this temperature range annealed CuBe alloys are homogeneous(solution annealing). The homogeneous state can be frozen through rapid cooling to room temperature (quenching). Through a subsequent annealing at 325°C the desired precipitation hardening is achieved which results in a significant increase in mechanical strength and electrical conductivity of CuBe (Table 5.17). The final strength and hardness values depend on the annealing temperature and time as well as on the initial degree of cold working (Table 5.18) and (Figs. 43 – 75)(Figs. 5.29 - 5.31).

Fig. 5.28: Phase diagram of copperberyllium with temperature ranges for brazing and annealing treatments
Phase diagram of copper- beryllium with temperature ranges for brazing and annealing treatments

As precipitation hardening alloys CuBe materials, mainly CuBe2 and CuBe1.7 have gained broad usage as current carrying contact springs because of their outstanding mechanical properties. Besides these CuCo2Be and CuNi2Be, which have medium mechanical strength and a relatively high electrical conductivity, are also used as contact carrier materials. After stamping and forming into desired contact configurations these CuBe materials are then precipitation hardened. CuBe alloys are available as semi-finished materials in a variety of cold work conditions. They can also be supplied and used in the already precipitation hardened condition without significant strength losses. In this case the hardening was already performed at the alloy producer.

Since Beryllium is rated as a carcinogen by the European regulation EU-67/548, it has been tried to reach the application properties of the well established CuBe1.7 and CuBe2 alloys with a lower Be content. The development efforts for alternate precipitation hardening materials without toxic and declaration requiring additive materials, for example CuNiCoSi, are aimed at the replacement of CuBe.

Figure 2 Fig. 5.29: Precipitation hardening of CuBe2 at 325°C after different cold working

Figure 3 Fig. 5.30: Precipitation hardening of CuBe2 (soft) at 325°C

Figure 4 Fig. 5.31: Precipitation hardening of CuBe2 (half hard) at different annealing temperatures

Precipitation hardening of CuBe2 at 325°C after different cold working
Precipitation hardening of CuBe2 (soft) at 325°C
Precipitation hardening of CuBe2 (half hard) at different annealing temperatures

Table 5.17: Physical Properties of Selected Copper-Beryllium Alloys (2 Teile!)

Table 5.18: Mechanical Properties of Selected Copper-Beryllium Alloys (2 Teile!)

5.1.6.2 Other Precipitation Hardening Copper Alloys

5.1.6.2.1 Copper-Chromium Alloys

As the phase diagram shows, copper-chromium has a similar hardening profile compared to CuBe Figure 5(Fig. 5.32). In the hardened stage CuCr has limitations to work hardening. Compared to copper it has a better temperature stability with good electrical conductivity. Hardness and electrical conductivity as a function of cold working and precipitation hardening conditions are illustrated in (Figs. 6 – 9) Figs. 5.33-5.35, ??? (Tables 5.19) and Table 1 (Tab. 5.20).

Copper-chromium materials are especially suitable for use as electrodes for resistance welding. During brazing the loss in hardness is limited if low melting brazing alloys and reasonably short heating times are used.

Fig. 5.32: Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium
Copper corner of the copper-chromium phase diagram for up to 0.8 wt% chromium

Figure 6 Fig. 5.33: Softening of precipitation-hardened and subsequently cold worked CuCr1 after 4hrs annealing

Figure 7 Fig. 5.34 a: Electrical conductivity of precipitation hardened CuCr 0.6 as a function of annealing conditions

Figure 8 Fig. 5.34 b: Hardness of precipitation hardened CuCr 0.6 as a function of annealing conditions

Figure 9 Fig. 5.35: Electrical conductivity and hardness of precipitation hardened CuCr 0.6 after cold working

Softening of precipitation-hardened and subsequently cold worked CuCr1 after 4hrs annealing
Electrical conductivity of precipitation hardened CuCr 0.6 as a function of annealing conditions
Hardness of precipitation hardened CuCr 0.6 as a function of annealing conditions
Electrical conductivity and hardness of precipitation hardened CuCr 0.6 after cold working


Table 5.19: Physical Properties of Other Precipitation Hardening Copper Alloys (2 Teile!)

Table 5.20: Mechanical Properties of Other Precipitation Hardening Copper Alloys

Material

Hardness

Condi- tion

Tensile

Strength Rm

[MPa]

0,2% Yield

Strength Rp02

[MPa]

Elongation

A50

[%]

Vickers

Hardness

HV

Spring Bending

Limit FFB [MPa]

CuCr

R 230a

R 400a R 450b R 550b

> 230

> 400

> 450

> 550

> 80

> 295

> 325

> 440

30

10

10

8

> 55

> 120

> 130

> 150

350

CuZr

R 260a

R 370a R 400b R 420b

> 260

> 370

> 400

> 420

> 100

> 270

> 280

> 400

35

12

12

10

> 55

> 100

> 105

> 115

280

CuCr1Zr

R 200a

R 400b

R 450b

> 200

> 400

> 450

> 60

> 210

> 360

30

12

10

> 70

> 140

> 155

420

5.1.6.2.2 Copper-Zirconium Alloys

The solubility of Zirconium in copper is 0.15 wt% Zr at the eutectic temperature of 980°C Figure 10 (Fig. 5.36). Copper-zirconium materials have a similar properties spectrum compared to the one for copper-chromium materials. At room temperature the mechanical properties of copper-zirconium are less suitable than those of copper chromium, its temperature stability is however at least the same.

Copper corner of the copper- zirconium for up to 0.5 wt% zirconium
5.1.6.2.3 Copper-Chromium-Zirconium Alloys

The earlier used CuCr and CuZr materials have been partially replaced over the years by the capitation hardening three materials alloy CuCr1Zr. This material exhibits high mechanical strength at elevated temperatures and good oxidation resistance as well as high softening temperatures. In its hardened condition CuCr1Zr has also a high electrical conductivity (Bild 5.37). Their usage extends from mechanically and thermally highly stressed parts such as contact tulips in high voltage switchgear to electrodes for resistance welding.

Fig. 5.36: Copper corner of the copperzirconium for up to 0.5 wt% zirconium

Copper corner of the copper- zirconium for up to 0.5 wt% zirconium

Fig. 5.37: Softening of CuCr1Zr after 1 hr annealing and after 90% cold working

Softening of CuCr1Zr after 1 hr annealing and after 90% cold working

References

References