Universality of quenching-partitioning-tempering local equilibrium model

Abstract

• Microstructural amount and C γ in low-C and medium-C Q-P-T steels were quantitatively characterized. • The QPT-LE model is a novel tool for the design of Q&P/Q-P-T steels. • The universality of QPT-LE model was firstly verified. The design of metastable retained austenite (RA) and its stability have always played a vital role in developing advanced high strength steels (AHSSs). The quenching-partitioning-tempering local equilibrium (QPT-LE) thermo-kinetic model was established by us, with consideration of carbide precipitation and interface migration. As a tool for designing AHSSs, the above model can well predict the microstructural amount and the carbon content in RA ( C γ ) in a high-C quenching-partitioning-tempering (Q-P-T) steel. In this work, QPT-LE model predicates the microstructural amount and C γ in low-C and medium-C Q-P-T steels more accurately than constrained carbon equilibrium (CCE) model without consideration of carbide precipitation and interface migration, and more accurately than quenching and partitioning-local equilibrium (QP-LE) model without consideration of carbide precipitation, which verifies the universality of QPT-LE model. The advantages of QPT-LE model are also discussed.