Slow cooling rate as furnace cooling can increase the values of hardness.

锻后冷却方式对硬度影响较大，冷却速度越慢，硬度值越高；

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Slow cooling rate as furnace cooling can increase the values of hardness.

锻后冷却方式对硬度影响较大，冷却速度越慢，硬度值越高；

youdao