Table 1 Physical properties of metallic tungsten and copper
|
performance
|
Density
g/cm3
|
Thermal expansion
Coefficient
10-6/℃
|
Thermal conductivity
w/(m·k)
|
Heat capacity
J/(kg·℃)
|
Elasticity
Modulus
GPa
|
Poisson density
|
Melting point
℃
|
Strength
MPa
|
|
Tungsten
|
19. 32
|
4. 5 |
174 |
136
|
411
|
0. 28
|
3410
|
550
|
|
Copper
|
8. 93
|
16. 6
|
403
|
385
|
145
|
0. 34
|
1083
|
120
|
Table2 Performance parameters of tungsten - copper alloy for electric alloy
|
Name
|
Symbol
|
Copper
|
Silver
|
Impurities
|
Tungsten
|
Density
|
Resistance
|
Conductance
|
Hardness
HB
|
Bending strength
|
|
Copper tungsten 50
|
CuW50
|
50±2
|
|
0.5
|
Margin
|
11.85
|
3.2
|
54
|
1128
|
|
|
Copper tungsten55
|
CuW55
|
45±2
|
|
0.5
|
Margin
|
12.30
|
3.5
|
49
|
1226
|
|
|
Copper tungsten60
|
CuW60
|
40±2
|
|
0.5
|
Margin
|
12.75
|
3.7
|
47
|
1373
|
|
|
Copper tungsten65
|
CuW65
|
35±2
|
|
0.5
|
Margin
|
13.30
|
3.9
|
44
|
1520
|
|
|
Copper tungsten70
|
CuW70
|
30±2
|
|
0.5
|
Margin
|
14.34
|
4.1
|
42
|
1716
|
790
|
|
Copper tungsten75
|
CuW75
|
25±2
|
|
0.5
|
Margin
|
14.50
|
4.5
|
38
|
1912
|
885
|
|
Copper tungsten80
|
CuW80
|
20±2
|
|
0.5
|
Margin
|
15.35
|
5.0
|
34
|
2158
|
980
|
|
Copper tungsten85
|
CuW85
|
15±2
|
|
0.5
|
Margin
|
15.90
|
5.7
|
30
|
2354
|
1080
|
1, High voltage switch with electrical alloy
Tungsten copper alloy in the high voltage switch 128kV SF6 circuit breaker WCu / CuCr, and high pressure vacuum load switch (12kV 40.5KV1000A), arrester is widely used, high pressure vacuum switch small size, easy to maintain, use a wide range, Burning and corrosive environments. The main performance requirements are resistance to arc ablation, anti-welding, cut-off current is small, less gas, low thermal emission capacity. In addition to conventional macro performance requirements, but also requires porosity, microstructure and performance, it is necessary to take a special process, vacuum degassing, vacuum infiltration and other complex processes.
2, Electric processing electrodes EDM electrode early use of copper or graphite electrode, cheap but not resistant to ablation, and now basically has been replaced by tungsten copper electrode. Tungsten copper electrode has the advantage of high temperature, high temperature strength, arc erosion, and conductive thermal conductivity, heat fast. Applications are concentrated in EDM electrodes, resistance solder electrodes and high voltage discharge tube electrodes.
The electrode is characterized by a wide variety of specifications, small quantities and total volume. The tungsten and copper material used as an electroformed electrode should have as high a density as possible and uniformity of the tissue, especially elongated rod, tubular and shaped electrodes.
