改善铬钼模具钢综合性能的热处理工艺研究

Study on heat treatment process to improve the comprehensive performance of chrome molybdenum steel

铬钼模具钢有很高的硬度和耐磨性,在冷作模具中应用十分广泛,但该钢种强韧性较低,易导致模具早期失效。为了提高铬钼模具钢模具的强度和韧性,研究了一种强韧化处理工艺,材料经锻造、余热淬火、高温回火、机械加工后,进行真空淬火加3次回火,再经线切割后采用冷处理及表面强化处理。通过这种热处理工艺,不仅保证了模具强度和硬度,同时又提高了模具的韧性和抗冲击能力,从而使模具获得了最佳的综合机械性能,模具的使用寿命成倍增加。

Chrome molybdenum steel possesses high hardness and wear resistance, so it is widely used in the cold working dies. But its low strength and toughness can easily lead to premature failure of the die. In order to improve the strength and toughness of chrome mo- lybdenum steel die, a strengthening-toughening heat treatment process is investigated. The steel is processed by forging, after heat hardening, high temperature tempering, machi- ning, vacuum quenching and three times tempering, wire electrode-cutting, cold treatment and surface strengthening treatment. The treatment process not only can ensure the die＇s strength and hardness, but also improve its toughness and impact resistant ability, so that the die and mould can obtain the best comprehensive mechanical properties and multiplied service life.