Tensile and Plane Bending Fatigue Properties of Two TRIP Steels at Room Temperature in the Air—A Comparative Study

Due to worldwide environmental concerns, automobile industries are trying to reduce the weight of the vehicles without compromising the crashworthiness by employing high-strength steel sheets as much as possible. Transformation-induced plasticity (TRIP) steels, relatively newer in the structural application, might play an important role in this regard. In this present work, tensile and plane bending fatigue properties and fracture behaviors of two low-alloy TRIP (TRIP590 and TRIP780 grades) steels were investigated at room temperature in air. After mechanical tests, fractographic observations were carried out in the SEM. Both steels showed reasonably high values of elongations and fatigue limits. However, with an increase in the bending stress level, the fatigue performance of TRIP780 steel improved gradually.