Tungsten Copper Explosive Powder Compaction
Tungsten copper explosive powder compaction method is the use of explosive shock wave generated by the metal or non-metal sintering compacted powder processing technology. When the shock wave through the metal powder, which the powder received extrusion, collision, friction between the particles, the thermoplastic must cut and micro-jet.
Using a mixture of explosive RDX and ammonium nitrate, explosives, detonation velocity of 5000m / s, explosives packed density of 1.0g / cm3, the explosive filling thickness of 18mm. Test uses a purity greater than 99.9% of copper powder and 99.8% purity tungsten powder, copper powder, tungsten powder particle size are 200 mesh. By 92% W-8% Cu (mass fraction) ratio of ball milling. Consolidation explosive device inside pipe diameter of 18 / 22mm, the alloy powder filled pipe, tube ends sealed with metal plugs, end plugs each ends with a 2mm hole through hydrogen reduction can be carried out, the mixed powder initial installation density of 50%. In the milling of the mixed powder, filling, especially heated metal end plug seal welding process, will produce mixed oxide powder. So to the initial installation of the powder through H2 reduction, reduction temperature is too high, it is possible to make the grain growth, the other due to the lower melting point of copper, easy to form a high temperature fusion of copper grains were not conducive to the reduction; temperature low reduction is not complete, so the distribution set different temperatures (600,700,800,850 ℃) through hydrogen reduction at 2h, judgment was reducing effect at different temperatures, after the reduction of explosive compaction apparatus evacuated and sealed.
After the W-Cu alloy powder by hydrogen reduction at 850 ℃ 3h, it was 98% of the density of the composite material. Each component within the composite structure and maintain a uniform distribution of the elements, in the form of composite fracture of intergranular fracture, with explosive compaction method were W-Cu samples were annealed, the hardness of 330HV, conductivity of 20MS / m, good physical properties.