FINITE ELEMENT SIMULATION OF SUPERPLASTIC BULGING WITH A DIE UNDER DIFFERENT PRESSURE MODES
超塑性充模胀形的有限元模拟

The optimum pressure norm in superplastic bulging with a die is determined by tracing the element with the largest strain rate and maintaining the strain rate at the optimum value, and the bulging processes under two kinds of pressure modes including constant pressure and optimum pressure norm are simulated by using large rigid-viscoplastic finite element method (FEM). The numerical results of the two pressure modes are compared and the effects of the strain rate sensitivity index m on the bulging process is analysed simultaneously.