净化催渗离子渗氮及渗层性能研究

Research on Purification Permeation Plasma Nitriding and Nitriding Layer Performance

采用阶段性通入含氮气氛的方法,探究净化处理对N80钢离子渗氮的影响。采用金相显微镜、显微硬度计、XRD分析离子渗氮层。结果表明:净化处理对离子渗氮具有明显的催渗作用。净化处理的催渗作用随着净化时间的延长和净化温度的升高而增加。但处理时间过久或温度过高,起不到催渗作用,反而造成金属表面脱碳,影响离子渗氮效果。净化处理20 min后550℃离子渗氮6 h,渗氮层厚度约0.55 mm,比未经净化处理的离子渗氮层厚约0.2 mm,且渗氮层硬度梯度减小,韧性提高。

The effects of purification treatment on the ion nitriding of N80 steel were researched by using the method of passing into the nitrogen atmosphere in stage. The nitriding layer was analyzed by optical microscope, microhardness tester and XRD. The results show that the purification treatment has obvious enhancing permeation effect on the ion nitriding. The permeation effect increases with the increase of temperature and time of the purification treatment. But the too long purification treatment time or too high temperature can not play a role in enhancing permeation effect, instead result in metal surface decarburization. When the purification treatment is 20 min, then ion nitriding is for 6 h at 550℃, the thickness of the nitriding layer is about 0.55 mm, which is thicker about 0.2 mm than the niaiding layer without purification treatment, and the hardness gradient of the nitriding layer reduces, and the toughness is enhanced.