Controlled optimization of Mg and Zn in Al alloys for improved corrosion resistance via uniform corrosion

Aluminum alloys are the predominant metal used in various industrial applications due to their light weight, excellent corrosion resistance, high strength, and good plasticity. The aim of this work is to develop an Al alloy with high corrosion resistance while maintaining its mechanical properties. In this work, we investigated the effect of the addition of small amounts of Mg and Zn on the corrosion properties of the Al1XXX series alloys by preparing Al-xMg-yZn (0.10 < wt% of x < 1.00, 0.10 < wt% of y < 0.55) samples and compared them to conventional commercial Al1070 alloys. The addition of a comparatively small amount of Mg and Zn led to the formation of beta and tau phases. We found that the formation of phases at the grain boundary of the Al-Mg-Zn alloy leads to the transition from pitting corrosion to intergranular corrosion thus increasing the overall corrosion resistance. This study contributes to providing new and further insights into the development of excellent corrosion characteristics in Al1XXX alloys.