Improved Simulation of Local Necks in Quick Plastic Forming 2008-01-1441
Two alternative finite element formulations are described which consider the influence of normal stress components on sheet deformations in Quick Plastic Forming . The new formulations, single field bricks and multi-field shells, were implemented in the forming simulation program PAM-STAMP  using a non-linear viscoelastic constitutive relation [3,4]. Simulations of two industrial components indicate that both new elements simulate local necking more accurately than the standard shells which ignore normal stresses. The multi-field shells require slightly more calculation time than the standard shells and significantly less than equivalent brick models.