Investigating the Effect of T6 Heat Treatment on Mechanical Properties of 7075 Al Alloy
الموضوعات :
Mohsen Emami
1
(Department of Mechanical Engineering, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran)
Vahid Hasan Nasab
2
(Department of Mechanical Engineering, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran)
الکلمات المفتاحية: T6 Heat Treatment, Age Hardening, Aluminum Alloy 7075, Taguchi, Mechanical Properties, Optimization,
ملخص المقالة :
Age hardening is one of the most important methods used to improve the mechanical properties of non-ferrous alloys such as nickel, titanium, magnesium, and aluminum alloys. However, finding the optimal age hardening parameters to achieve higher mechanical properties—such as hardness, yield stress, tensile strength, and fatigue life—is essential. In this study, the effect of T6 heat treatment parameters, including solution and aging conditions, on the mechanical properties of commercial alloy 7075 was investigated. The Taguchi method was employed to design the experiments and analyze the results. Solution temperature, solution time, aging temperature, and aging time were the T6 heat treatment factors considered in this design. Temperatures of 430, 470, and 510 °C and times of 15, 35, and 55 minutes were set as the solution treatment levels. Additionally, temperatures of 140, 170, and 200 °C and times of 2, 7, and 12 hours were determined as the aging treatment levels. Upon optimization, the material achieved a Vickers hardness of 137.28 HV, yield strength of 266.91 MPa, tensile strength of 377.64 MPa, elongation to break of 15.19%, and fatigue life of 1,193,304 cycles. According to the research findings, achieving optimal mechanical properties such as hardness, tensile strength, and fatigue strength requires specific and distinct heat treatment conditions.
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