Cr12MoV钢等离子体氮碳共渗工艺及稀土催渗

Process parameters and effect of rare earth element on plasma nitrocarburzing of Cr12MoV steel

对Cr12MoV钢在510～520℃、NH3流量为60 mL/min时不同时间、NH3/CO2不同气氛比值、不同等离子体共渗炉压的氮碳共渗工艺进行了研究。通过金相、XRD、SEM、EDS、摩擦磨损实验,探究了氮碳共渗优化工艺及稀土加入对Cr12MoV离子氮碳共渗的影响。结果表明:对于冷作模具钢Cr12MoV,时间为10 h、NH3/CO2为10∶1、炉压为500～700 Pa时,实验效果优化。另外,随着稀土镧的加入,渗层增厚且白亮层更致密,硬度梯度更平缓,氮碳共渗效果更佳。

Plasma nitrocarburizing treatment was carried out for Crl2MoV steel with different process parameters. The parameters was optimized based on the orthogonal experiments and the influences of addition of rare earth on plasma nitrocarburizing of Cr12MoV steel were examined by optical microscope, XRD analysis, SEM, EDS analysis and wear tests. The results show that the optimal parameters of plasma nitrocarburizing treatment for Cr12MoV steel are as follows： nitrocarburizing time is 10 h, the ratio of NH3 to CO2 is 10：1 under the pressure of 500-700 Pa. In addition, the thicker nitrocarburized layer is observed and the more flatter gradient of hardness distribution in the layer is obtained for the plasma nitrocarburized treatment with the addition of lanthanum.