Effect of Nickel on Corrosion Resistance of Al-Zn-Mg-Cu PM Alloy Produced by Mechanical Alloying

Kahtan S. Mohammed, Haider T. Naeem, Raid T. Hadi

Abstract: In this research, comparative study of corrosion resistance of PM Al-Zn-Mg-Cu alloy (A) and PM Al-Zn-Mg-Cu-1 %Ni alloy (B) produced using mechanical alloying process has been investigated. PM milled alloy (A) and alloy (B) specimens were sintered after compaction then homogenized, aged then retrogressed and reaged. PM Al-alloys were subjected to corrosive media (acidic: 1.0M HCl) and using weight loss method to evaluate their corrosion resistance. The findings of this study indicated that the precipitation hardening is obtained for PM milled Al- alloy A samples after heat treatment led to enhance their resistance of corrosion. Furthermore, the gain of corrosion resistance for PM Al-Zn-Mg-Cu-Ni alloy B specimens more than what PM Al-Zn-Mg-Cu alloy A caused by having in compounds of Al-Ni as well as precipitates of alloying elements, under the same operation conditions. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to show the corroded surfaces.

Keywords: Al-Zn-Mg-Cu-Ni PM alloy, Mechanical alloying, Corrosion resistance