Considerations in the Application of the 'Quenching and Partitioning' Concept to Hot Rolled AHSS Production

摘要

The "quenching and partitioning," or Q&P, concept involves partial transformation of austenite to mar-tensite, followed by carbon transport from the carbon-supersaturated martensite into untransformed austenite, thereby stabilizing it to room temperature. This concept has been studied by several research groups for potential application to TRIP-type sheet products produced by cold rolling and annealing. In the present contribution, the Q&P concept is considered in the context of hot strip mill processing, including alloy and process design, as well as fundamental differences with cold rolled Q&P processing and potential industrial issues. Non-isothermal partitioning behavior during coil cooling is predicted, and initial simulations are reported for a 0.19C, 1.6Mn, 1.6Si (wt. percent) TRIP steel. High strengths are found with significant levels of retained austenite, although further optimization studies are needed to fully assess the capability of this process concept.