INFLUENCE OF DAMAGE AND TEXTURE EVOLUTION ON LIMIT STRAIN IN BIAXIALLY STRETCHED ALUMINUM-ALLOY SHEETS

A numerical code has been developed to calculate limit strains of text ured aluminum alloy sheets. This code is based on the Marciniak-Kuczyn ski (M-K) model, but allows for void nucleation and growth so that bot h limit strain and fracture strain can be predicted. The strain induce d void nucleation model was employed together with the Cocks and Ashby 's void growth model. The influences of initial texture, texture evolu tion, and void nucleation and growth during deformation on the limit s trains of an A-Mg alloy were all investigated. Satisfactory agreement was obtained between the predictions and measured data. It was also sh own that the introduction of void damage into the old M-K model can le ad to more reasonable and accurate predictions. (C) 1998 Elsevier Scie nce S.A. All rights reserved.