材料期刊网

采用双层辉光等离子表面合金化技术对45钢进行表面渗Nb处理，用OM、SEM和XRD分析了渗Nb层的显微组织、化学成分及其相组成，测试了渗Nb合金层的显微硬度和表面耐磨性。结果表明：经过离子渗Nb处理后可获得约10μm的表面合金层；渗层中Nb含量随渗层深度呈梯度变化，渗层与基体结合牢固；XRD表明其表面形成Fe3Nb3C，Fe2Nb，NbC和Nb6C5等相。摩擦磨损试验表明：Nb的渗入使45钢基体摩擦系数由0.80左右降到了0.15，磨损失重仅为基体的18%，大大提高了耐磨性能。

Plasma niobiumizing was conducted on 45 steel using the double glow plasma surface alloying technique to improve its wear resistance. The microstructure, composition distribution and phase constituents of the niobiumizing layer were investigated by ways of OM, SEM and XRD respectively, the surface microhardness and wearability of the niobiumizing layer were also tested. The thickness of niobiumizing layer is approximately 10μm.The concentration of Nb decreased gradually along the depth of alloying layer which contributed a metallurgical bonding with the matrix. A ball-on-disc wear test was also carried out at room temperature. The results indicated that the friction coefficient decreases from 0.80 to 0.15 and the worn mass is only 18% of that of the matrix, so friction and wear resistance can be both improved remarkably.