Instrumentation and Control of a Bulge Test on a Superplastic Pb-Sn Alloy

Superplasticity is characterized by high elongations under a high strain rate sensibility, and it’s variation with strain rate, temperature and grain size. This parameter is often obtained from uniaxial tensile test. However, superplastic deformation is a biaxial process; hence there is a need to develop a way to get this parameter in a biaxial test. This work aims to set up the instrumentation to record and control a biaxial superplastic forming in a Pb-Sn alloy. The control system project has been divided into tracking variables: strain and pressure. The instrumentation is able to predict the breaking point at the beginning of the superplastic forming process from biaxial testing.