Reasons for the suppression of temper brittleness in steels with rapid electric tempering

The phenomenon of first-order temper brittleness, which is defined by a reduction in impact strength, by an increase in the ductile-brittle transition temperature, and by an increase in the proportion of the brittle component in a fracture, is observed in steels after tempering in the range 350–500°C. For steels inclined toward temper brittleness, it is recommended that during traditional heat treatment low-temperature (200–250 °C) and high-temperature (550–600°C) tempering is used which may not always provide the optimum combination of strength and ductility properties. Features are considered in the present work for the effect of rapid tempering on the properties of steel 30KhGSA.