Mechanical behaviour modelling and finite element simulation of simple part of Ti-6Al-4V sheet under hot/warm stamping conditions

Abstract : In order to reduce production costs and environmental impact, the cycle time reductions associated with a decrease in temperature levels are relevant. This study focuses on the behaviour modelling of Ti-6Al-4V alloy at temperatures between 400 °C and 500 °C in order to obtain greater formability than at room temperature, whilst remaining below SPF conditions to reduce tool, workshop and energy costs. Mechanical tests are conducted to identify elasto-viscoplastic model parameters. They use displacement field measurements obtained by Digital Image Correlation (DIC) and based on innovative surface preparation patterns adapted to high temperature exposures. Different material parameters are identified to define a model that is able to predict the mechanical behaviour of Ti-6Al-4V alloy under hot/warm stamping conditions. Then, an omega shape forming test is developed to validate the behaviour model. Finally, the experimental results are compared with numerical simulations which require the implementation of the behaviour model formulation into an FE code.