Effect of Reinforcement Ratio on Physical and Mechanical Properties of Cu-W Composites Synthesized by Ball Milling

In this study, the effect of addition of W-reinforcements on physical and mechanical properties of Cu-W composites was investigated. For this aim, two different powder mixtures containing elemental copper (Cu) and various amounts of tungsten (W) were milled in a planetary type ball mill. In order to prevent excessive cold welding among powder particles, stearic acid was also added to each powder mixture at a constant ratio. Characterization of powders and microstructural analyses of the samples were carried out using laser diffractometry (Mastersizer) and scanning electron microscopy (SEM). Sintered densities were determined by Archimedes' technique of diethyl phthalate displacement. The hardness and electrical conductivity of the samples were tested using a Microhardness tester and a conductivity meter, respectively. It was found that powder particle size gradually decreases with increasing W-reinforcement and milling time. Moreover, density and microhardness values of the samples increase whereas electrical conductivity decreases with increasing W content.