Characterization of fracture in TRIP 1180

Abstract

This study investigated the characteristics of fracture in TRIP 1180 for the first time. Four different tests were performed, namely, uniaxial tension, three-point bending, bulge and hole expansion tests. Three directions of specimens were prepared for material with longitudinal axes oriented at 0º, 45º and 90º relatively to the rolling direction. A digital image correlation system was used to measure the strain for three point bending and bulge test. Thickness strain was measured manually using vernier calipers. The fracture angle was calculated manually after the fracture photograph was greatly magnified. Dimples were observed on all fractures, regardless of the type of test, indicating they were ductile fractures. There were large differences between the fracture angle of the sample and the result obtained from the theoretical expression in uniaxial tensile test. The fracture diagram by linking the four experiment results were attempted to know fracture characteristics of TRIP 1180 steel.