研究采用双层辉光离子渗金属技术在Ti-6Al-4V合金表面制备Mo基改性层的Mo扩散过程。通过观察渗层截面组织形貌,测定各种合金化元素的分布情况,着重分析不同温度下不同元素的加入对Mo扩散行为的影响。结果表明:在800~950℃下,Ti-6Al-4V合金离子渗Mo后所得改性层厚度、Mo平均扩散系数及相同浓度下Mo的扩散系数都随温度升高而升高;由于反溅射和Ti-6Al-4V基体相变等原因,1000℃时各参数反常;加入合金元素W和N使Mo的扩散系数有所降低,Mo的平均扩散系数在单纯渗Mo时为2.37688×10^-4,W-Mo共渗时为1.47127×10^-4,W-Mo-N共渗时为7.02681×10^-5。
The molybdenum-based alloying layers on the surface of Ti-6Al-4V were prepared by a plasma surface alloying process.The microstructure and element distribution of the modified layers were examined.The diffuse process and the impact of temperature and alloying elements to diffusion coefficients of Mo(DMo) were studied.The results show that the depth of the molybdenum alloying layers,the mean diffusion coefficients of Mo(DMo) and the DMo at the same Mo concentration increase with increasing temperature in the rang of 800-950℃,while they are abnormal at 1 000℃ for the comprehensive influence of sputter and phase transition of the Ti6Al4V sample.Addition of tungsten and nitrogen reduces the DMo in different degrees,and Mo D values for alloying layers with Mo,W-Mo and W-Mo-N are 2.376 88×10^-4,1.471 27×10^-4and 7.026 81×10^-5,respectively.