New Strategy for the Prediction of the Gas Pressure Profile of Superplastic Forming of Al-5083 Aluminium Alloy

Abstract:

This paper describes a new approach for identification of the optimum pressure history for SPF processes, based on mechanisms-based hyperbolic constitutive equations. This equation set has been modified to incorporate the effect of the damage behaviour the material suffers due to the cavitational evolution of Al-5083 superplastic alloy. A large deformation, multiaxial formulation of the constitutive equation set is implemented and applied to finite element modelling of a bulge test forming process to characterise the cavitation evolution behaviour in the bulge test, using conventional (constant strain rate) and the newly proposed (variable strain rate) strategy.

• Periodical: Materials Science Forum (Volume 735)
• Pages: 204-209
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.735.204
• Online since: December 2012
• Authors: Nagore Otegi, Lander Galdos, Iñaki Hurtado, Sean B. Leen
• Keywords: AA5083 Aluminum Alloy, Cavitation, Mechanisms-Based Constitutive Equations, Superplastic Forming

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