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The WCu composite material has both a high ductility, good electrical and thermal conductivity, and other characteristics of the copper, but also has of tungsten high strength, high hardness, low coefficient of expansion, and other characteristics. These unique properties make tungsten copper alloys in electrical contact, especially as the upgrading of new products in the high pressure switch contact materials, resistance welding electrode materials, electronic packaging and thermal deposition material on behalf of silver copper alloy contact material, etc. is widely available to become an important functional materials. Powder injection molding from the plastic injection molding, powder metallurgy technology and plastic injection molding technology, metal die casting technology combine to produce a new type of near net shape technology, including mixing, forming, degreasing, sintering four processes. The metal powder injection molding technology to produce the small size and the shape of complex products, technical and cost advantages compared to other traditional forming methods. In this thesis, using mechanical alloying, injection molding and other advanced materials processing technology, successfully prepared WCu40 and WCu15 series alloy materials. Analysis by X-ray diffraction, scanning electron microscopy and other advanced analytical tools, as well as a combination of theoretical analysis and experimental analysis, WCu series alloy material. Select the optimal preparation parameters, the appearance of mechanical alloying powder morphology, particle size distribution, lattice constant do further analysis; simultaneously WCu15 contact material the DC conditions under arc corrosion characteristics arc corrosion contact surface morphology changes. The results show that: With the mechanical alloying process proceeds, the Cu particles to achieve crushing small and evenly distributed on the sheet W base, as the milling time, the lattice constant of Cu is increased, the lattice constant of W decreases, the Cu diffused into the W in solid solution to form an unsaturated. Alloy material prepared WCu series, a second phase of Cu particles are small and uniform distribution on the W matrix having dispersed characterized subtle tissue; after the injection molding of the product, the relative density of 94.2%; with increasing W content, WCU series conductivity and reduced elongation of the alloy material, the hardness and strength; under the conditions of 17V, 12A, WCu alloy contacts after electrical contact test, and the contact surface appears the Cu-rich area, rich W area, holes, pores, etc. kinds of electrical erosion morphology. With the increase in the number of operations, the quality of contact cathode increases with increasing W content, the total mass transfer reduction of the contact, the mass transfer of the WCu15 alloy contact is smaller than the pure copper contacts contact the mass transfer WCu15 Priority pure Ag contacts instead of Ag contact material, a meaningful exploration.
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