The invention provides a spheroidizing annealing technology of H13
hot work die steel and belongs to the field of die steel heat treatment technologies. The spheroidizing annealing technology of the H13
hot work die steel comprises the steps that (1) a forged H13 steel blank is cooled to the temperature of 400-500 DEG C, the cooled H13 steel blank is fed into a furnace, the temperature is raised to 720-750 DEG C at the temperature raising speed of 25-80 DEG C per hour for preheating, the temperature is kept for 1-2 hours, the temperature is then raised to 980-1050 DEG C at the temperature raising speed of 25-80 DEG C per hour, after all the furnace charge reaches the temperature, the temperature is kept for 3-5 hours, then the temperature of the forged H13 steel blank is lowered to be not higher than 550 DEG C through furnace cooling, and
air cooling and discharging are conducted; hot charging is conducted, the temperature is raised to 900-950 DEG C at the temperature raising speed of 25-80 DEG C per hour, after all the furnace charge reaches the temperature, the temperature is kept for 0.5-1 hour,
air cooling and discharging are conducted, and then the pre-treatment process is completed; and charging is conducted at the temperature 300-400 DEG C, the temperature is raised to 880+ / -10 DEG C at the temperature raising speed of 25-80 DEG C per hour, the temperature is kept for 4-6 hours, the temperature is lowered to 760+ / -10 DEG C at the
cooling speed of 15-20 DEG C per hour, after the temperature is kept for 8-12 hours, the H13
hot work die steel is cooled to be lower than or equal to 500 DEG C at the
cooling speed of 15-20 DEG C per hour, and then
air cooling and discharging are conducted. The spheroidizing annealing technology of the H13 hot work die steel has the advantages that carbides are evenly distributed in the structure, the structure is refined, the defects of network carbides and the like in an original structure are eliminated, and the annealing
hardness is lowered.