Ductility evaluation for small plate specimens by fracture surface shape change

Abstract

In this study, tensile tests were conducted on small plate specimens of varying thicknesses to assess the impact of specimen geometry on ductility evaluation. The findings revealed that both fracture elongation and reduction in fracture surface area decreased as plate thickness diminished. Finite element analysis indicated that stress triaxiality at the center of the specimen increased with decreasing plate thickness, contributing to a reduction in fracture strain. Examination of the fracture surfaces showed that the rate of thickness reduction due to deformation was higher for thinner plates. For small plate specimens with a thickness of t=0.75 (SS-J3), the reduction rate of the fracture surface in the width direction was only marginally less than that of the round bar, and the modes of deformation and fracture closely resembled those of the round-bar. Therefore, in SS-J3 specimens, deformation of the fracture surface in the width direction may serve as a reliable indicator for ductility evaluation.journal articl