Comparative Study of Quench and Partition Processes in High Si and High Al Steels

Abstract:

The quench and partition process is a means to develop third-generation high-strength steels using many possible process variants. In this work, two variants of quench and partitioning heat treatments, one-step and two-step, were carried out for high Si and high Al steel alloys. The kinetics of isothermal transformation occurring during the one-step quench and partition process were analysed using dilatometry. Experimental analysis revealed the swing-back phenomenon in high Si steel, and the transformation characteristics above and below the M_s temperature differed. The high Al alloy resulted in higher retained austenite (19%) compared to high Si steel (17%) during the one-step quench and partition process. Aluminium addition favoured bainite formation more than silicon addition. A comparison of two heat treatment variants shows the two-step quench and partition heat treatment seemed preferable as it produced more retained austenite (22%) in the high Si steel.

• Periodical: Materials Science Forum (Volume 1105)
• Pages: 99-104
• DOI: https://doi.org/10.4028/p-5NcQhf
• Online since: November 2023
• Authors: Vinod Kurup*, Charles Witness Siyasiya, Roelf J. Mostert
• Keywords: Bainite, Dilatometer, High Al, Isothermal Transformation, Quench and Partitioning Process, Swing Back Phenomenon

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