Abstract: In view of the problem of Cr12MoV steel roll cracking easily and hardened layer depth during induction hardening, the effects of preheating temperature, quenching heating temperature, induction coil moving speed and power frequency on hardness, cracking and hardened layer depth of the Cr12MoV steel roll were studied, and the method of Cr12MoV steel roll with high hardness without cracking and thick hardened layer was explored. The results show that when the quenched and tempered hardness of the Cr12MoV steel roll is lower than 32 HRC and the preheating temperature is higher than 450 ℃, quenching cracking can be avoided. With the increase of induction hardening temperature or the moving speed of the induction coil, the hardness of the hardened Cr12MoV steel roll increases first and then decreases, but the hardened layer depth is not significantly affected. However, with the decrease of induction power frequency, the hardened layer depth of hardened Cr12MoV steel roll increases obviously, but it has little effect on hardness of hardened Cr12MoV steel.

Key words: Cr12MoV steel roll, induction hardening, preheating temperature, hardness, hardened layer depth