Effect of Secondary Aging Process on the Structure and Properties of 7050 Aluminum Alloy Forging

Abstract:

The effect of the second-stage aging process on the tensile properties, fracture toughness and electrical conductivity of 7050 aluminum alloy die forgings was studied, and the mechanism of strengthening and toughening was analyzed by transmission electron microscope and scanning electron microscope. The results show that with the extension of the second-stage aging time, the morphology of the precipitation phase remains unchanged, but the average radius of the precipitation phase and the distance between each other gradually increase. The fracture modes at this aging temperature are mixed fracture mechanisms of dimple fracture and intergranular fracture, and the number of dimple fractures increases with time. With the extension of the second-stage aging time, the strength of the alloy decreases, and the fracture toughness and stress corrosion resistance increase. The alloys heat-treated at 120°C×6 h +177°C×6~8 h two-stage aging process have excellent comprehensive properties.

• Periodical: Key Engineering Materials (Volume 861)
• Pages: 57-64
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.861.57
• Online since: September 2020
• Authors: Wei Wei He*, Min Hao, Hui Qu Li, Liang Wang, Jun Zhou Chen
• Keywords: 7050 Aluminum Alloy Die Forging, Aging, Fracture Tough-Ness, Microstructure, Precipitate, Tensile Property

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