BEHAVIOUR OF SUPERPLASTIC MATERIALS AT LARGE STRAINS.

In this paper, some of the issues concerning the behaviour of superplastic materials at large strains are addressed. The development of necks during tensile tests is dealt with. Here the crucial role of grain growth-induced strain hardening is examined. This leads directly to a discussion of strain-enchanced grain growth during superplastic flow, in which the nature of the phenomenon is examined. Attention is then turned to the development of cavitation damage at large strains, and in particular to the role of cavity coalescence.