Influence of Microstructural Parameters on the Corrosion Resistance of 7075 Aluminum Alloy

The aim of this analysis was to identify the cause of poor corrosion resistance of final product, after the slight change of heat treatment of initial material. Although the hardness of material prior and after the change was the same, significant difference in microstructure was revealed by microstructural analysis. Change in heat treatment process led to heterogeneous distribution of precipitates and increase in the precipitate size which caused deterioration in corrosion resistance. Based on the findings, further optimization of heat treatment was suggested. More importantly, initial material inspection based on microstructural analysis, not only mechanical testing, was recommended.