Quantitative determination of homogeneous strain value in superplastic tension

Abstract

After load instability, a passage of homogeneous strain e can be still continued in superplastic tensile deformation. But untill now, no one has given the precise value of e corresponding to actual materials, neither in experimental measurements nor in theoretical calculations. Using the elaborate experimental measuring methods of m value and its function expressions, the note first gives the method to determine homogeneous e, and the homogeneous e value of typical superplastic alloy Zn-5% Al under 18°C and 340°C respectively.