A Study on Modelling the Superplastic Behaviour of Ti54M Alloy

Abstract

Superplastic forming is a cost-effective process for manufacturing complex-shaped titanium parts. TIMETAL® 54M (Ti54M) is a titanium alloy that has been commercially available since 2003, however studies on modelling its superplastic behaviour are scarce in the literature. Finite element modelling can be used to enable the manufacturing of complex-shaped parts economically as the number of experimental trials can be reduced. This paper illustrates the implementation of a microstructural-based model to predict the superplastic behaviour of Ti54M alloy during forming at elevated temperature. The parameters of the material model are derived in this work for the Ti54M alloy. A Matlab script has been developed for the calculation and calibration of the material model parameters based on material experimental data. The material model was implemented into the finite element commercial software Abaqus by means of a user-defined subroutine. The finite element calculations take into account also grain size evolution. Finally, a pressure profile was numerically calculated for forming a non-commercial part via superplastic forming targeting optimal conditions for the material.