Influence of Three-Step Aging Heat Treatment on Properties of 7A04 Aluminum Alloy

Abstract:

Aiming at traditional peak aging of 7A04 Aluminum Alloy with high strength but low corrosion resistance, innovative gradually cooling three-step aging heat treatment process were designed, conventional mechanical properties and corrosion resistance of 7A04 aluminum after three kinds of aging treatments was studied through microstructure. The results show that compared with the traditional peak aging process, two gradually cooling three-step aging process is to improve materials tensile strength, plastic and impact toughness in different degrees. Meanwhile corrosion resistance of materials has improved significantly. And extension of low temperature aging time is conducive to the further improvement of strength.

• Periodical: Materials Science Forum (Volumes 704-705)
• Pages: 645-649
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.704-705.645
• Online since: December 2011
• Authors: Qiu Ze Li, Lei Xu, Ji Xiao Song, Jing Han, Xing Min Huang, Guang Ze Dai
• Keywords: 7A04 Aluminium Alloy, Corrosion Resistance, Heat Treatment, Mechanical Behavior, Microstructure

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