Superplastic forming of Ti-4Al-3Mo-1V alloy: flow behavior modelling and finite element simulation

Abstract

Superplastic forming process of Ti-4Al-3Mo-1V alloy was optimized via an integrated approach. Material characterization, flow behavior modelling, finite element simulation (FES), and superplastic forming (SPF) were the steps of the study. The as-processed sheets were characterized via uniaxial constant strain rate tests at 750-900 °C and 1×10-4-1×10-2 s-1, which considered the superplasticity ranges of this alloy. The flow behavior was modelled using hyperbolic sine law constitutive equation (CE) and the artificial neural network (ANN). The constructed models were assessed via the cross-validation technique, which declare better predictability of the CE model comparing to the ANN model. The stress-strain data was used to adjust the mechanical properties of studied alloy inside the FES program, DEFORM 2D/3D. In this step the optimized pressure-time dependence was computed for SPF. The FES results were verified by experimental SPF via lab machine. The Ti-4Al-3Mo-1V alloy was successfully formed by superplastic forming technique using the proposed integrated approach.