Experimental investigation on heat treatment of a high-speed steel for hot rolling roll mill

The authors describe the researching results to optimise the hardening and tempering of the high carbon high-speed steel for rolls containing 2.38%C, 5.07%V, 6.34%Mo, 5.09%Cr, 1.20%Ni, 1.17%Nb, 0.09%Ti and 0.05%RE by means of light optical microscope (LOM), scanning electron microscope (SEM), backscattered electron image (BSE), X-ray diffraction (XRD), and hardness, tensile strength, impact toughness and wear testers. The results show that the microstructure of above casting high-speed steel is given by a tempered martensitic matrix surrounded by eutectic carbides. Casting high-speed steel has higher hardness quenching at 1280 K-1340 K, and it has higher hardness, tensile strength, impact toughness, and abrasive wear resistance tempering at 793 K-833 K. The comprehensive properties of casting high-speed steel is the best while air-cooling quenching about 1340 K and tempering about 813 K.