Experimental Studies and FEM Analysis on the Creep Age Forming for Aluminium Alloy 7050

Abstract:

Creep age forming (CAF) is a combined creep forming and age hardening treatment process. How to control the springback after forming is one of the key problems for the process. In this paper, Creep tests were conducted for different stress levels at 160°C for 25h, which is the suitable parameters for CAF process of aluminum alloy 7050T451. Based on experimental results, a set of mechanism-based creep constitutive equations was formulated. The six material constants of the constitutive equations were determined by non-linear least squares fitting methods. The creep age forming process for aluminum alloy 7050T451 plate was simulated by using FE software ABAQUS through the subroutine CREEP. The effects of the forming parameters on the springback were analyzed. Finally, experimental research was performed. It is found that the developed numerical simulation can be used to simulate the whole process of creep age forming process. The maximum relative error is 6.9%.

• Periodical: Materials Science Forum (Volumes 773-774)
• Pages: 144-152
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.773-774.144
• Online since: November 2013
• Authors: Xia Huang, Yuan Song Zeng, Pen Tao Gai
• Keywords: Aluminum Alloy 7050, Creep Age Forming, Springback

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