Optimization of superplastic hydroforming process of Aluminium alloy 5083

Superplastic forming of Aluminium alloy 5083 in hydroforming process is simulated using commercially available finite element software. The process is simulated at three different constant pressures through which the applied pressure effects on important parameters such as thickness distribution, final dome height, and distributions of equivalent stress and strain are evaluated. The superplastic forming process is also modeled at constant strain rate by applying two different algorithms for pressure control, which guarantee that the maximum strain rate is kept close to the optimum value. In the absence of experimental data, the calculated history of applied pressure is compared with the available analytical results. The forming process of a circular sheet in a rigid conical die at constant optimum strain rate is also simulated by using the pressure control algorithm. The influence of the friction coefficient between the die and sheet on pressure profile and final thickness profile are investigated. (C) 2007 Elsevier B.V. All rights reserved.