Effect of Al Content on Microstructure and Properties of Zn-Cu-Al Alloy

Abstract Zn-Cu-Al zinc alloy was prepared by metal mould casting. The effects of Al addition on the microstructure, electrical conductivity and wear resistance of Zn-Cu-Al alloy were studied. The results show that the structure of Zn-Cu-Al alloy is composed of Zn solid solution containing Cu and Al (η phase), eutectic phase (α+η) and CuZn5 (ε phase); Al0.4Zn0.6 phase appeared when Al addition content exceeded 2.0wt.%; With the increase of Al addition content, eutectic phase (α+η) content increased and η phase grain refined. Meanwhile, the hardness and electrical conductivity of the alloy increase with the increase of Al addition content. When the addition of Al is 5.0 wt.%, the hardness and electrical conductivity of the alloy reach the maximum, 151HV and 26.4% IACS, respectively. The wear mechanism of the alloy is mainly plastic deformation with a mixture mode of plastic deformation and adhesion.