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Critical point of heat treatment of Chinese grade 45 steel (℃)

Posted:2021-05-24 14:46:55

The general heat treatment process of Chinese grade 45 steel is as follows:

1) Softening treatment: 740 - 760℃ × 4 - 6h, at the cooling rate of 50 - 100℃ / h, the furnace is cooled to 600℃ and discharged for air cooling.

2) Normalizing: heating at 850 - 870℃, air cooling after discharging.

3) Quenching and tempering: 840 - 860℃, 450 - 550℃.

4) Quenching + tempering: 820 - 840℃ heating quenching, according to the actual situation, select the appropriate coolant; The tempering process depends on the required mechanical properties of the workpiece.