Fuel cap stamping simulation of AA5754 sheets using a microstructure based macro-micro multi-scale approach.

Abstracts A macro–micro multi-scale approach is applied to study the fuel-cap forming process to identify the effects of friction, material constitutive behavior and microstructural features on formability of aluminum sheets. In the sample level (macro-scale) model, lower friction at contacts between blank and dies/post are found to delay the onset of necking. This is due to the fact that the materials from the center and outer regions are less hindered by frictional force to flow to the regions of most severe deformation. High work hardening index and strain rate sensitivity are seen to effectively delay necking and enhance the fuel cap stamp formability. Particle distributions in the microstructurally-based sub-model are shown to play a weak role in pre-necking deformation, and have a large influence on post-necking deformation. The post-necking through-thickness thinning process, however, is very fast and makes a minor contribution to the total formability from initial deformation to final fracture, suggesting that continuous cast aluminum sheets with particle stringers may be used for stamping fuel cap component as efficiently as the direct chill cast aluminum sheets which a more homogeneous particle distribution. [ABSTRACT FROM AUTHOR]