Void Nucleation, Growth, and Coalescence Observed by Synchrotron Radiation X-ray Laminography during Tensile Deformation of Fe–0.02 mass% N Alloy

Abstract

High-strength steel is required in many industries. However, elongation decreases as strength increases. Therefore, many types of high-strength steels have been developed in order to improve the balance of these mutually contradictory properties. These representative steel types are dual-phase (DP) steels, comprising mixtures of ferritic and martensitic 1) or bainitic phases, 2) and transformation-induced plasticity (TRIP) 3)-assisted steels, 4) in which the austenitic-martensitic phase transformation is triggered by deformation. Some studies 5,6) have investigated the effects of the microstructures of DP and TRIP steels on the strength and elongation