An alternative method for the production of TRIP steels has been evaluated, based on low-carbon, high-manganese alloy concepts and batch annealing cycles. Significant levels of austenite have been developed in the experimental steels, and the stability of the austenite was determined to be a function of both intercritical annealing temperature and annealing time. Very fine- or ultrafine-grained ferrite-austenite-martensite microstructures resulted in strength-ductility combinations between currently available dual-phase and TRIP steels, and the recently introduced TWIP steels. Challenges in evaluating the micro-structure of the experimental materials have been addressed, in part, through the application of EBSD analysis. However, the ability to truly quantify the proportion of ferrite and martensite was complicated by difficulties accounting for grain boundaries and partially recrystallized constituents.
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