Effect of tungsten content on the structure, physical and mechanical properties of silicon bronze (Cu-3 wt%Si)

Abstract

This research investigated the effect of tungsten content on the structure, physical and mechanical properties of silicon bronze (Cu-3 wt%Si). Tungsten was added in concentrations of 0.1, 0.3, 0.5, 0.8, 1 and 1.5 wt%. The samples were produced using permanent die casting technique, machined and stored for the structural analysis, physical and mechanical tests. The microstructural analysis of the control sample (Cu-3 wt%Si) revealed the presence of dendrite of intermetallic compounds which could be primary silicon and copper silicide (Cu3Si) phases while the alloy doped with tungsten consisted of fine grains of intermetallic compounds evenly dispersed in the copper matrix. The mechanical tests results showed that addition of tungsten to silicon bronze significantly increased the percentage elongation, ultimate tensile strength, hardness and electrical conductivity of the alloy by 174.5%, 741.2%, 98.9% and 14.9% respectively. Maximum percentage elongation, electrical conductivity, ultimate tensile strength and hardness of 25.8%, 61.25% IACS, 286 MPa and 358 BHN respectively were obtained.