Effect of artificial aging on micro-corrosion behavior of 7075 aluminum alloy

doi:10.13251/j.issn.0254-6051.2024.02.023

Abstract

Abstract: Effect of aging time on corrosion behavior of the 7075 aluminum alloy was investigated by means of corrosion electrochemical measurements, scanning electron microscope, transmission electron microscope and EDS elemental analysis. The results show that the specimen aged for 6 h at 120 ℃ has a higher self-corrosion potential and a lower corrosion driving force than the specimens aged for 2, 12 and 24 h, and the alloy aged for 6 h is less prone to corrosion. As the aging time increases, the overall corrosion profile of the alloy changes from intergranular corrosion to pit corrosion. Through the early corrosion morphologies of the substrate observed by using transmission electron microscope, the alloy aged for 6 h shows uniformly distributed shallow corrosion hollows on the surface, while the alloy aged for 24 h shows deep corrosion pits. The uniform distribution extent of solute elements in the substrate has a significant impact on the pitting behavior of the alloy.

Key words: 7075 aluminum alloy, artificial aging, corrosion morphology, precipitated phase

CLC Number:

TG146.2⁺1

Tang Huizhen, Wang Shuai, Yan Lijuan, Zhang Yongchao, Shen Jun, Ge Binghui. Effect of artificial aging on micro-corrosion behavior of 7075 aluminum alloy[J]. Heat Treatment of Metals, 2024, 49(2): 153-158.

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