表面预处理对钛合金表面低温等离子体氮化的影响  

Surface Modification of TC4Ti-Alloy by Acid/Plasma Etching and by Low Temperature Plasma Nitriding

作　　者：李金龙 滕越 张开策 郭媛媛 吕哲 王亚男 周艳文 李春福 LI Jinlong;TENG Yue;ZHANG Kaice;GUO Yuanyuan;LV Zhe;WANG Yanan;ZHOU Yanwen;LI Chunfu(Surface Engineering Institute,School of Materials and Metallurgy,School of Applied Technology,University of Science and Technology Liaoning,Anshan 114051,China)

机构地区：[1]辽宁科技大学材料与冶金学院表面工程研究所应用技术学院,鞍山114051

出　　处：《真空科学与技术学报》2021年第2期132-138,共7页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(51972155,51702145);辽宁省科技厅项目(SKLMEA-USTL-201709);辽宁科技大学产业技术研究院重大应用项目(601012431-10)。

摘　　要：为提高TC4钛合金表面摩擦学性能,探究酸洗及等离子体预处理对TC4钛合金表面低温等离子体氮化进程的影响。首先采用热丝增强等离子体氮化系统分别对表面酸洗及未酸洗TC4钛合金在氩气气氛下进行等离子体预处理,然后对各种表面预处理的TC4钛合金实施低温(500℃)等离子体氮化。采用扫描电子显微镜、能谱仪及X射线衍射仪分别分析了试样的截面形貌、氮势分布和物相组成;采用显微硬度计、摩擦磨损仪和轮廓仪测试氮化后TC4钛合金表面的显微硬度、磨痕曲线和摩擦系数,并计算了磨损量。结果表明:低温氮化后TC4钛合金基体组织形貌不变,表面获得厚度约10μm的氮化层。氮化后TC4钛合金的XRD衍射峰均向低角度偏移,表明形成含氮固溶体相。其中酸洗复合30 A等离子体预处理的TC4钛合金氮化后,XRD衍射峰向低角度偏移最明显,偏移量达0.2°。与基体相比,酸洗复合30 A等离子体预处理的TC4氮化表面显微硬度提高至691 HV,磨损量仅为基体的16%。酸洗复合等离子体预处理有效去除TC4钛合金表面氧化层、粗化表面,促进低温等离子体氮化进程,有利于含氮固溶体相形成,从而提高其表面摩擦学性能。The surfaces of TC4 Ti-alloy,an advanced functional material in high-tech industries,were modified by acid/plasma etching and by hot-filament enhanced low-temperature plasma nitriding.The influence of the acid/plasma etching on the microstructures,interfacial adhesion and tribological properties of nitrided TC4 Ti-alloy was investigated with X-ray diffraction,scanning electron microscope,energy dispersive spectroscopy and conventional mechanical probes.The results show that the acid/plasma etching had a major impact.Specifically,the acid/plasma etching significantly improved the surface cleanliness,removed the oxide/passivation layer,increased the surface roughness and thickness of nitrided layer,activated the surface reaction,promoted the formation of N-containing solid solution and enhanced the interfacial adhesion.Most importantly,the 10 μm nitrided layer,on the TC4 alloy pre-etched by acid/plasma,exhibited a micro-hardness of 691 HV and a wear-rate 84% lower than that of TC4 Ti-alloy.

关 键 词：钛合金 低温等离子体氮化 酸洗复合等离子体预处理 摩擦学 显微硬度 

分 类 号：TB79[一般工业技术—真空技术]