The Effect of Quenching and Partitioning (Q&P) Heat Treatment on the Microstructure and Mechanical Properties of High Boron Steel

Materials

卷:14

Tian Xie¹  Teng Wu¹  Zhao Li¹  Run Wu¹  Mingwei Li¹  Yu Wang²  Song-Sheng Zeng³ 

[1] Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081, China;

[2] Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052, Australia;

[3] Valin ArcelorMittal Automotive Steel Co, Ltd., Loudi 417009, China;

关键词: high boron steel;    Q&;    P heat treatment;    retained austenite;    TRIP effect;    wear resistance;   

DOI  :  10.3390/ma14061556

来源: DOAJ

【 摘 要 】

High boron steel is prone to brittle failure due to the boride distributed in it with net-like or fishbone morphology, which limit its applications. The Quenching and Partitioning (Q&P) heat treatment is a promising process to produce martensitic steel with excellent mechanical properties, especially high toughness by increasing the volume fraction of retained austensite (RA) in the martensitic matrix. In this work, the Q&P heat treatment is used to improve the inherent defect of insufficient toughness of high boron steel, and the effect mechanism of this process on microstructure transformation and the change of mechanical properties of the steel has also been investigated. The high boron steel as-casted is composed of martensite, retained austensite (RA) and eutectic borides. A proper quenching and partitioning heat treatment leads to a significant change of the microstructure and mechanical properties of the steel. The net-like and fishbone-like boride is partially broken and spheroidized. The volume fraction of RA increases from 10% in the as-cast condition to 19%, and its morphology also changes from blocky to film-like. Although the macro-hardness has slightly reduced, the toughness is significantly increased up to 7.5 J·cm⁻², and the wear resistance is also improved.

【 授权许可】

Unknown