Numerical analysis of the influence of various factors on forming the limit of hydrostatic bulging for ductile materials

Abstract

The influences of various factors on the limit strain of the hydrostatic bulging of a circular clamped sheet of ductile and damaged materials have been analyzed with the rigid-viscoplastic finite element method. These factors include strain hardening, strain-rate sensitivity, yield surface shape and the inhomogeneous distribution of cavitation. It has been shown that the average limit thickness strain for hydrostatic bulging increases linearly with both strain hardening exponent ( n) and strain rate sensitivity ( m) of material. For damaged material, the average limit thickness strain for the case that initial maximum cavitation locates at the periphery of circular sheet is much larger than that at the pole.