A new numerical strategy for SPF pressure profile computing based on statistical strain rate controlling

International audienceThis paper investigates the designing of Superplastic Forming pressure cycles in order to propose rapid forming sequences that suit industrial strategy, and which enable the control of microstructure evolutions. An optimization algorithm using ABAQUS® coupled with MATLAB® has been developed in order to improve forming cycles while allowing superplasticity. The numerical strategy is based on an algorithm controlling a statistical maximum of the distribution of strain rate of non-formed elements of part mesh instead of the maximum strain rate on the whole mesh for classical optimization algorithms. The objective of this method is to exclude numerical singularities that are used for pressure controlling in traditional techniques. This paper details firstly the new algorithm and then presents numerical and experimental results for different forming conditions obtained from industrial, classical, and optimized pressure cycles. These tests were performed on Ti-6Al-4V titanium alloys