Mechanical Engineering, University of Tabriz
Elastic-plastic finite-element analysis applied to metalforming allows the real macroscopic properties of the workpiece to be incorporated. This paper presents the results of an experimental study of the initiation of cracking in side-pressing of a heat-treated aluminium alloy (Duralloy 2014). Using an F. E. analysis, these are related to various fracture criteria. It is found that the criterion of generalised plastic work correlates well with the change in fracture site from the centre of the billet to the outer corner as the geometric shape becomes more oblate. For central cracks the limiting deformation is about 13%, but when these are suppressed the deformation can continue to nearly 50%.