Heat treatment process of D2 cold modul steel

Vacuum heat treatment furnace of D2 cold modul steel

D2 modul steel is a commonly used cold working modul steel, and its performance is much better than CR12MO1V1 modul steel in all aspects. In addition, D2 modul steel has a good hardness performance after heat treatment, and its hardness can reach more than 59HRC.

First to stress relieving,which is in the workpiece after rough machining, heating to 600 ~ 650 ℃, for thermal insulation and 2 h, finally with the furnace cooled to 500 ℃, from air cooling.
Second, slow hardening is the workpiece temperature to 600 ℃, then heat to warm up for the first time, 20 min after the mean temperature to 850 ℃, and 30 min in the second preheating, heat preservation last heating to 1020 ~ 1040 ℃, the heat preservation of 25 ~ 40 min, from air cooling.

Third tempering: temper immediately after quenching, and temper at least twice, each heat preservation time is not less than 2 hours.Which is worthy of our attention should be timely after quenching tempering, prevent craze, and to prevent surface decarbonization, gauge and high precision mould should be cryogenic treatment (70 ℃), and high temperature tempering is adopted to reduce the workpiece deformation, high temperature tempering temperature 500 ~ 560 ℃, hardness greater than 58 HRC.