Tungsten Copper Applications
WCu alloys are used where the combination of high heat resistance, high electrical and/or thermal conductivity, and low thermal expansion are needed. Some of the applications are in electric resistance welding, as electrical contacts, and as heat sinks. As contact material the alloy is resistant to erosion by electric arc. WCu alloys are also used in electrodes for electrical discharge machining and electrochemical machining.
The CuW75 alloy, with 75% of tungsten, is widely used in chip carriers, substrates, flanges and frames for power semiconductor devices. The high thermal conductivity of copper together with the low thermal expansion of tungsten allows thermal expansion matching to silicorn, gallium arsenide, and some ceramics. Other materials for this applications are CuMo alloy, AlSiC, and Dymalloy.
Alloy with 70-90% of tungsten is used in liners of some specialty shaped charges. The penetration is enhanced by factor 1.3 against copper for homogeneous steel target, as both the density and the break-up time are increased. Tungsten powder based shaped charge liners are especially suitable for oil well completion. Other ductile metals can be used as binder in place of copper as well. Graphite can be added as lubricant to the powder.
1. High performance materials used in spaceflight field
Tungsten copper alloy has such excellent performances as heat-resistant, ablate-resistant, high-intensity, high-density and self-cooling,so it is widely used in spaceflight field.
2. Electrical Contact materials
Electrical contacts are subjected to extreme mechanical and thermal stresses during operation. For fractions of a second, temperatures rise to several thousand degrees as a result of the arcing. Our tungsten-Copper materials are used owing to their unique physical properties.
Advantages: without other element except tungsten and copper, uniform material, low content of gas and impurity, very high burn-off resistance, excellent thermal and electrical conductivity, all necessary joining and machining processes.
3. Electrodes?for?Spark?Erosion
Our?WCu?electrodes?are?best?suitable?for?EDM?machining?of?those?materials.
Advantages:?low?wear,?high?contour?sharpness,?good?machinability.
Types?of?product:?rods,?tubes?and?plates.
4. Electronics Packaging Materials
_ Ability to vary metal matrix density to achieve optimum combination of CTE and TC values
_ Excellent dimensional stability unaffected by high temperature cycling
_ Machinable to exceptional flatness and surface finish
_ Superior thermal conductivity compared to competitive products
_ Metallization capability includes electrolytic and electroless plating and thin film deposition
These characteristics make Refractory Metal& Ceramics Branch’s tungsten composites ideally suited for high power laser diode applications, silicon and III-V semiconductor materials, DWDM optical platforms and optoelectronic packages.
Dimentional:
W-Cu heat sinks galvanically plated with Ni or NiAu or electroless Ni plated
Semi-finished products: up to 100x100mm with a thickness of 0.5 to 50mm.
Tyipicaldde Heat Sink of WCu
| Material Composition(wt%) | W-10Cu | W-15Cu | W-20Cu | W-25Cu | W-30Cu |
| Denisty (g/cm3) | 17.1 | 16.4 | 15.5 | 14.8 | 14.2 |
| TC (W/m·K) | 191 | 198 | 221 | 235 | 247 |
| CTE (×10-6/K) | 6.3 | 7.1 | 7.6 | 8.5 | 9.0 |