Microstructure and Mechanical Properties of a Nb-Microalloyed Medium Carbon Steel Treated by Quenching-Partitioning Process
The recently developed “quenching and partitioning” heat treatment and “quenching-partitioning-tempering” heat treatment are novel processing technologies, which are designed for achieving advanced high strength steels (AHSS) with combination of high strength and adequate ductility. In present study, a medium carbon steel containing Nb was subjected to the Q-P-T process, and both the microstructure and mechanical properties was studied. The experimental results show that the Nb-microalloyed steel demonstrates high tensile strength and relatively high elongation. The microstructure of the steel was investigated in terms of scanning electron microscope and transmission electron microscope, and the results indicate that the Q-P-T steel consist of fine martensite laths with dispersive carbide precipitates and the film-like interlath retained austenite. The orientation relationships between martensite and retained austenite is as well-known Kurdjurmov-Sachs relationship and Nishiyama-Wasserman relationship.
Chunliang Zhang and Liangchi Zhang
K. Zhang et al., "Microstructure and Mechanical Properties of a Nb-Microalloyed Medium Carbon Steel Treated by Quenching-Partitioning Process", Key Engineering Materials, Vols. 531-532, pp. 596-599, 2013