Manufacture of high-dispersed W-Cu composite powder by mechano-thermal process

Abstract

In order to improve the process of co-reduction of oxide powder, a new mechano-thermal process was designed to produce high-dispersed W-Cu composite powder by high temperature oxidation, short time high-energy milling and reduction at lower temperature. The particle size, oxygen content and their sintering abilities of W-Cu composite powder in different conditions were analyzed. The results show that after a quick milling of the oxide powder for about 3–10 h, the reduction temperature of the W-Cu oxide powder can be lowered to about 650 °C from 700–750 °C owning to the lowering of particle size of the oxide powder. The average particle size of W-Cu powder after reduction at 650 °C is about 0.5 µm smaller than that reduced at 750 °C. After sintering at 1 200 °C for 1 h in hydrogen atmosphere, the relative density and thermal conductivity of final products (W-20Cu) can attain 99.5% and 210 W · m−1 · K−1 respectively.