| Explosive compaction of powders is a new technique that employs shock wave to compress powders to form solid components under high temperature and high pressure in a few microseconds, and is an important research object in the area of explosive applications. As a new technique of high-energy machining, explosive powder compaction has two distinct characteristics that the time acting on powders of explosive compaction is short and the detonation pressure is great.Tungsten carbide particle reinforced copper-based composites has been wildly used to make compound electric resistance welding electrode. The most commonly used powder metallurgy approach for producing such composites comprises processings of cold compaction and hot pressing and extrusion. The paper attempts to fabricate WC/Cu composites by explosive compaction technique.The thesis documents emphatically analyze the state of equation of powders as well as the macroscopical and microcosmic mechanism of explosive compaction of powders, also the action of shock wave on powders in load settings.The experiments have been made to compact powders of WC/Cu with cylindrical configuration/single tube set-up by symmetrical sliding detonation, expecting to get excellent electrode material. By improving on the setting of explosive compaction, adverse factors affecting the quality of compacts are eliminated after a lot of experiments. Ultimately well compacts are made by such operations as blending powders, deoxidizing, vacuumizing the settings of explosive compaction.The state of equation of powders of WC/Cu and the P-V curve are worked out. The macrostructure, microstructure and performances of composites are examined. The optimal parameters are gotten according to the effects of the ratio of explosive mass to powder mass, the detonation velocity, impact energy on the density.Finally, the conclusion has been made that the WC/Cu composites fabricated by explosive compaction can satisfy the needs for comprehensive performances.
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