Numerical Analysis of Surface Roughening and Necking in Aluminum Alloy Tubes Under Internal Pressure

The crystal plasticity based finite element model is used to simulate surface roughening and localized necking in aluminum alloy tubes under internal pressure. A new approach for defining onset of necking is proposed. The effects of spatial orientation distribution, strain rate sensitivity, work hardening, and initial surface topography on surface roughening and necking are discussed. It is demonstrated that while localized necking is very sensitive to both the initial texture and its spatial orientation distribution, the initial surface topography on necking has only a small influence on necking.