Optimization of Superplastic Forming Process of AA7075 Alloy for the Best Wall Thickness Distribution

  • Manh Tien Nguyen Faculty of Mechanical Engineering, Le Quy Don Technical University, Ha Noi, Viet Nam
  • Truong An Nguyen Faculty of Mechanical Engineering, Le Quy Don Technical University, Ha Noi, Viet Nam
  • Duc Hoan Tran Faculty of Mechanical Engineering, Le Quy Don Technical University, Ha Noi, Viet Nam
  • Van Thao Le Advanced Technology Center, Le Quy Don Technical University, Ha Noi, Viet Nam
Keywords: superplastic forming, wall thickness distribution, optimization, response surface, AA7075 alloy


This work aims to optimize the process parameters for improving the wall thickness distribution of the sheet superplastic forming process of AA7075 alloy. The considered factors include forming pressure p (MPa), deformation temperature T (°C), and forming time t (minutes), while the responses are the thinning degree of the wall thickness ε (%) and the relative height of the product h*. First, a series of experiments are conducted in conjunction with response surface method (RSM) to render the relationship between inputs and outputs. Subsequently, an analysis of variance (ANOVA) is conducted to verify the response significance and parameter effects. Finally, a numerical optimization algorithm is used to determine the best forming conditions. The results indicate that the thinning degree of 13.121% is achieved at the forming pressure of 0.7 MPa, the deformation temperature of 500°C, and the forming time of 31 minutes.


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How to Cite
M. T. Nguyen, T. A. Nguyen, D. H. Tran, and V. T. Le, “Optimization of Superplastic Forming Process of AA7075 Alloy for the Best Wall Thickness Distribution”, Adv. technol. innov., vol. 6, no. 4, pp. 251-261, Aug. 2021.