Fabrication and characterization of W-15Cu composite powders by a novel mechano-chemical process

W-Cu nanopowder was successfully prepared by a novel mechano-chemical method, in which WO3 and CuO powders were first jet-milled in a high-pressure airflow, then reduced in H-2 to Convert into W-Cu composite powders. The starting and milled WO3 and CuO powders, as well as the resulting W-CU powders were characterized by X-ray diffraction analysis (XRD), transmission electron microscope (TEM) and laser particle size analysis. Property of the sintered W-Cu compacts was also investigated. It was shown that jet milling effectively reduces particle size of the starting WO3 and CuO powders. The W-Cu composite powder fabricated by the mechano-chemical process has nanosize of less than 100 nm and high-dispersed and homogeneous distribution of W and Cu components. The W-Cu composite powder exhibits high sinterability, and relative density of near 99% of the theoretical was achieved for W-Cu compacts sintered at 1200 degrees C. Furthermore, the sintered W-Cu parts showed good physical and mechanical properties. Maximum electrical and thermal conductivity are 185 W m(-1) K-1 and 25 m Omega(-1) cm(-1) for W-Cu compacts sintered at 1200 degrees C, respectively, and bending strength and Vickers hardness are 673 and 372 MPa, respectively. (C) 2007 Elsevier B.V. All rights reserved.