Infleunces of grainsize on fracture of superplaticity

摘要

The cavity growth process during superplastic deformation has been studied. A model for this process is proposed based on the theory of grain-boundary-sliding (GBS) and the theory of cavity growth. According to the deduced equation, the relationship between fracture strain and grain size at a specific temperature and strain rate is analyzed and discussed. It shows that the total elongation is an approximated to linear function of the inverse grain size for the superplastic materials.