The effect of Cu and Sb on the microstructure and mechanical properties in Sn-Sb-Cu-Ni-Cd whitemetal

The effects of Cu and Sb on the microstructure and mechanical properties of Sn-Sb-Cu-Ni-Cd whitemetal were investigated. Any compound phase was not observed in the whitemetal with 0.05 wt% Cu, while as the Cu content was increased, star- or needle-like Cu6Sn5 phases were found. The tensile strength gradually increased with Cu up to 5 % and then remained almost constant with Cu content above 5 %, while the hardness continuously increased with Cu content because of the increased hard Cu6Sn5 phases. As the Sb content increased, SbSn cuboids were present as well as Cu6Sn5. The tensile strength and hardness continuously increased and the elongation decreased with Sb content.