Measurement of edge fracture strain of dual-phase steels by in-plane bending test

Abstract

Edge ductility of dual phase steels is highly affected by the preparation of the edge and especially shear cutting has a detrimental effect on the formability. In this study, a novel in-plane bending test is used to characterize the edge ductility of dual-phase steels. Digital image correlation technique is employed to calculate the fracture strain along the edge in the desired material orientation. The proposed test setup isolates the material-dependent aspects, namely damage and hardening, from those resulting from testing procedure factors such as contact stresses and friction compared to conventional hole expansion capacity (HEC) test. The results show that the edge crack phenomenon depends on the material orientation.