High temperature strain measurement by digital image correlation and ductile fracture evaluation of Ni-based superalloy

Abstract

Tensile and compression tests at 850℃ were conducted by using 6 types of specimen for ductile fracture evaluation of Ni-based superalloy. The digital image correlation method was applied to measure the strain during the tensile tests. Fracture strain, Lode angle parameter and stress triaxiality were obtained by the finite element analysis of the tensile and compression tests. These parameters were used to calibrate the material parameters of the modified Mohr-Coulomb (MMC) ductile fracture model.