Research Progress on the Influence of Microstructure on Stress Corrosion Behavior and Mechanisms of 7000 Series High-Strength Aluminum Alloys

Abstract

The 7000 series (Al-Zn-Mg-Cu) high-strength aluminum alloy is one of the highest strength aluminum alloy series.Stress corrosion cracking (SCC) is a key factor affecting its service safety and stability.In this paper, the anodic dissolution mechanism and hydrogen-induced cracking (HIC) mechanism of SCC were reviewed, and the effects of microstructure on SCC behavior and mechanism of the 7000 series aluminum alloy were summarized.Based on the effects of chemical composition of the alloy, heat treatment, pre-strain and surface treatment on SCC sensitivity, the effects of different microstructures on SCC behavior were discussed.The key research directions to reduce the SCC sensitivity of the 7000 series high-strength aluminum alloy were put forward:the microstructure of the alloy is reasonably regulated by optimizing the alloying elements, using new heat treatment processes and surface treatment technologies, to improve the service life of the alloy and better protect the aluminum material.

Keywords

• 7000 series high-strength aluminum alloy； organizational structure； stress corrosion cracking； anodic dissolution； hydrogen induced cracking； research progress