Microstructural studies of W-10Â wt.% Cu composites prepared by using ultrafine composite powder

Tungsten-copper (W-Cu) composites containing 10 wt.% Cu (W-10Cu) were prepared by pressing and sintering a type of ultrafine composite powder. Constituent phases, grain size and orientation relationship between W and Cu grains were characterized and investigated. The results show that W-10Cu composites are composed of W and Cu elementary substance and orientation relationship between W and Cu grains is defined as 1¯1¯4Cu//01¯1W and (131)Cu//(200)W. The existence of the orientation relationship depends largely on the two factors. First, the grain sizes of both W and Cu were in the nanoscale range. Secondly, the interplanar spacing between both phases can match well owing to the residual stress of the W/Cu interface. Consequently, the obtained composites exhibited high density and excellent thermal conductivity.