Investigation on the hardness characteristic of high carbonised high chromium steel with cryogenic quenching

This paper investigates the mechanical behaviour of untreated High Carbonised High Chromium steel (HCHCR) with cryogenically treated HCHCR concerning its hardness. To enhance the properties like wear resistance, hardness, and toughness, the conventional heat treatment process was used. Nitriding and carburizing are the most widely used heat treatment process for surface treatment, tempering, and hardening. But 100% transformation of austenite at room temperature into martensite doesn't take place in any conventional hardening process. Even after the quenching process, some of the austenite remains in the martensite matrix and is retained as austenite. The austenite remaining in the martensite matrix exerts internal pressure in the structure and controls the expansion properties of the steel. The HCHCR material was quenched with liquid nitrogen and run at a low temperature of -80 ° C to -196 ° C for several hours. It converts austenitic resin to martensite and improves the grain structure of the steel. The results obtained show that retained austenite is converted to martensite, thereby increasing the hardness of the steel.