Tailoring the TRIP Effect in Q&P Steels using Strain Rate and Temperature

Phase metastability has emerged as a pathway to tailor the work hardening behavior of many unique structural alloys. For instance, the deformation induced martensitic phase transformation of austenite to martensite enhances the work hardening rate, and thus the formability and toughness of lean-alloy “Q&P” steels. In this talk, we will elucidate the roles of extrinsic deformation processing variables, such as temperature and strain rate, on the kinetics of the martensitic transformation. The relationship between microstructure evolution and strain hardening will be evaluated by mechanical tests complemented with in-situ X-ray diffraction and ex-situ electron backscatter diffraction. Our resolution of the martensitic phase transformation on both the bulk and micro-scale will explore pathways for tailoring the martensitic phase transformation of metastable steel alloys.