Preparation of highly dispersed superfine W–20 wt% Cu composite powder with excellent sintering property by highly concentrated wet ball-milled process

The ball milling process and the CuWO₄–WO₃ precursors were investigated, and a new highly concentrated wet ball-milled process (HWM) was designed. W–20 wt% Cu composite powders with excellent sintering property were synthesized by highly concentrated wet ball-milled process and co-reduction. The powders were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), field electron transmission electron microscopy (FESEM) and laser-diffraction diameter tester. The results indicate that particle size of WO₃–CuO powder mixtures decreases to 390 nm rapidly with the milling time increasing to 5 h. The CuWO₄ precursors promote the microstructural homogeneity of W and Cu. W–Cu composite powders have a highly dispersed and well sintering property. The particle size of W–Cu powders milled by HWM for 5 h is about 680 nm. High-resolution transmission electron microscopy (HRTEM) result suggests that W phase and Cu phase are mixed at nanometer scale. The above W–Cu composite powders reach the relative density of about 99.3%.