A study of premachined hole growth in superplastic materials

Because of cavities nucleation at the grain boundaries and their subsequent growth and coalescence large number of alloys show premature failure during superplastic flow. In this paper, the authors will introduce the study of the growth of void intentionally premachined on specimen subject to tensile test: in particular the effects of the material parameters on the void growth will be analysed. Tensile tests were conducted at constant crosshead velocity using a fine-grained Pb–Sn alloy that presents superplastic properties at room temperature. The results of the experiments are in good accordance with the numerical predictions obtained by using a code based on the finite element method.