Powder Characteristics of W - Cu Composite Powder Produced by Hydrogen Reduction
김태형Tae Hyeong Kim, 변준Joon Byeon, 이재성Jai Sung Lee
Abstract
An investigation has been performed to find the optimum production route for producing microhomogenous W-Cu composite powder by hydrogen reduction of WO₃-CuO oxide mixture. The optimum reduction condition was determined not only by TG and X-ray diffraction analysis of the phase decomposition occuring during reduction of WO₃-CuO mixture but also by investigating the powder characteristics and the mixing homogeneity of coreduced W-Cu powder. As a result, two stage reduction process has been established, consisting of the stepwise isothermal heat treatment at low (200℃∼300℃) and high temperatures(800℃). The experimental results revealed that the two stage reduction process is more effective than the one stage process for improving the refinement and the mixing homogeneity of W -Cu powder. This is mainly due to the fact chat tile first step isothermal reduction heating at low temperature efficiently inhibits Cu segregation and minimize the formation of W-Cu aggregates due to sintering of Cu powder.