42CrMoA钢制曲轴稀土离子氮碳共渗工艺研究

在不同温度、时间、气压及稀土含量下对42CrMoA钢进行了稀土离子氮碳共渗工艺试验,测定了不同工艺参数下表面强化层的硬度、厚度,并对比了稀土离子氮碳共渗工艺与其它表面强化工艺处理后的磨损性能和弯曲疲劳强度等力学性能进行了研究。结果表明:5%RE、520℃×2 h、1.05 kPa气压为该工艺的最佳参数;42CrMoA钢制高速增压柴油机曲轴用该工艺处理后,完全能满足其使用性能要求。

Rare Earth Ion Nitrocarburization Technique Used for 42CrMoA Steel Crankshafts

The paper did an experiment on 42CrMoA steel by using rare earth ion nitrocarburization technique at different temperature,time,atmospheric pressure and rare earth content.The surface hardness and the thickness of strengthened layers were measured under various parameters.The wear performance and bending fatigue strength of specimens treated by rare earth ion nitrocarburization were compared with those by other surface treatments.The experiment results show that the optimum parameters of this process are as follows: the rare earth content is 5%,and the treatment temperature,time and gas pressure are 520 ℃,2 hours and 1.05 kPa respectively.The 42CrMoA steel crankshaft treated with this technique can meet the performance requirements for 42CrMoA steel used in high-speed supercharge diesel engines.