Effect of Er on Microstructure and Corrosion Behavior of Al-Zn-Mg-Cu-Sc-Zr Aluminum Alloys.

In this study, the influence of Er addition on the microstructure, type transformation of second phases, and corrosion resistance of an Al-Zn-Mg-Cu alloy were explored. The results revealed that the added Er element could significantly refine the alloy grains and change the second-phase composition at the grain boundary of the alloy. In the as-cast state, the Er element significantly enhanced the corrosion resistance of the alloy due to its refining effect on the grains and second phases at the grain boundary.