Investigation of stress corrosion cracking initiation of 7A52 aluminum alloy

Abstract

The stress corrosion cracking(SCC) behaviour of 7A52 aluminum alloy in air and in 3.5% NaCl solution was researched by slow strain rate test(SSRT) and SEM-EDS. The SCC susceptibility was estimated with the loss of the reduction in area. The experimental results indicate that the SCC susceptibility of 7A52 aluminum alloy in 3.5% chloride solution is the highest at strain rate of 1×10⁻⁶ s⁻¹. The lowest one is under the condition of 1×10⁻⁵ s⁻¹. Stress concentration and anode dissolving around Al-Fe-Mn intermetallics initiate micropores which will result in microcracks. The existence of intermetallics in the microstructure may play an important role in understanding the SCC initiation mechanisms of 7A52 aluminum alloy.

Keywords

7A52 aluminum alloy / stress corrosion cracking / stress corrosion cracking susceptibility / intermetallics

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