Modeling of Yield Strength in Retrogression of RRA Treatment of Spray Formed Al-Zn-Mg-Cu Alloy

Abstract:

7075 alloy is the most typical Al-Zn-Mg-Cu alloy and widely used in industry. In the present study the regularities of the change for the size and volume fraction of the precipitates in the retrogression process and the effects of aging time on strengthening of spray formed 7075 alloy were investigated based on the thermodynamics, aging kinetics and hardening theory. The results show that there was a relationship between the parameters of retrogression treatment and yield strength of the alloy. A unified model is presented to establish the quantitative relations between the retrogression process and the yield strengths of spray formed 7075 alloy from the perspective of combining micro and macro.

• Periodical: Materials Science Forum (Volume 993)
• Pages: 146-151
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.993.146
• Online since: May 2020
• Authors: Rui Ming Su, Ying Dong Qu, Rong De Li*, Chang Tian, Sai Nan Nie
• Keywords: Al-Zn-Mg-Cu Alloy, Model, Retrogression, RRA, Yield Strength

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