Prediction of Ductile Metal Rupture with the E-W Model in PAM-CRASH 2003-01-2799
The use of high performance materials such as high strength steel grades, aluminum and magnesium alloys has raised the difficulty to accurately predict structural crash behavior: these materials are generally more prone to rupture than mild steel, and predicting rupture is still very difficult to achieve. In this paper certain facts behind metal rupture prediction are exposed together with the classical ways they have been approached in the past. A new “hybrid two parameter” model approach is proposed. These are models that include not only a measure of “damage” within the material but also a measure of the “critical volume” to be saturated with damage before the damage evolves to an ‘initial’ crack. The way this approach is manifested through the new E-W material rupture model in PAM CRASH is shown. Academic examples are presented with this new modeling capability and they are compared favorably with the existing academic literature evidence. Finally, pre-industrial application examples are shown to support the potential of the new E-W model to predict rupture phenomena in car body crash: aluminum car body parts, statically and dynamically loaded.