快速渗氮处理下的TC4钛合金的摩擦磨损性能  

Friction and wear properties of TC4 titanium alloy with high-speed nitriding treatment

作　　者：丁旭 王匀[1] 杜道忠 周泓 于超 刘为力 刘振强 李瑞涛 DING Xu;WANG Yun;DU Daozhong;ZHOU Hong;YU Chao;LIU Weili;LIU Zhenqiang;LI Ruitao(School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China;School of Public Service,Rural Construction College,Changzhou 213147,China)

机构地区：[1]江苏大学机械工程学院,镇江212013 [2]江苏城乡建设职业学院公共事业学院,常州213147

出　　处：《复合材料学报》2024年第8期4334-4343,共10页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(52105259);泰州市科技成果转化项目(SCG202220);泰州市科技支撑计划(TG202247);扬州市重点研发项目(SCY2022010022);无锡市科技攻关项目(G20222007);泰州市双创人才项目(泰人才办[2022]22号)。

摘　　要：为了改善TC4钛合金表面硬度、耐磨性较差的缺点,本文提出了基于超快高温烧结(UHS)工艺的快速渗氮处理(HSNT)表面处理方法。对TC4钛合金表面进行HSNT,利用X射线衍射仪和扫描电子显微镜研究试样的微观组织,采用维氏显微硬度计和摩擦磨损试验装置对试样进行力学性能测试。2 min即可在TC4钛合金表面形成改性层,改性层由两部分组成,最表层为氮化物层,厚度10μm,平均显微硬度为HV_(0.1)973.55,主要成分为Ti N;次表层为渗氮层,厚度10μm,平均显微硬度为HV_(0.1)774.53,截面显微硬度整体呈现出阶梯分布的趋势。摩擦磨损试验发现,在20 N载荷下,经过HSNT的TC4的摩擦系数为0.406,降低了24.4%,经过HSNT的TC4的磨损体积为0.302 mm^(3),降低了86.7%。不同载荷下经过HSNT的TC4的摩擦系数和磨损体积始终小于TC4钛合金,且均随着载荷的增加而增大。在20 N载荷下,TC4的磨损机制主要表现为磨粒磨损和氧化磨损,经过HSNT的TC4的磨损机制主要表现为粘着磨损和氧化磨损。经过HSNT的TC4钛合金的性能得到了明显的改善,弥补了TC4硬度低、耐磨性差的缺点。In order to improve the surface hardness and wear resistance of TC4 titanium alloy,a high-speed nitriding treatment(HSNT)based on ultrafast high-temperature sintering(UHS)process was proposed.HSNT was applied to the surface of TC4 titanium alloy,and the microstructure of the sample was studied by X-ray diffractometer and scanning electron microscope.The mechanical properties of the sample were tested by Vickers microhardness tester and friction and wear test device.The modified layer can be formed on the surface of TC4 titanium alloy in 2 min.The modified layer consists of two parts.The outermost layer is the nitride layer,the thickness is about 10μm,the average microhardness is HV_(0.1)973.55,and the main component is TiN.The sub-surface layer is nitriding layer,the thickness is also about 10μm,the average microhardness is HV_(0.1)774.53,the cross-section microhardness overall shows a trend of ladder distribution.The friction and wear test shows that under 20 N load,the friction coefficient of TC4 with HSNT is 0.406,which is reduced by 24.4%,and the wear volume of TC4 with HSNT is 0.302 mm^(3),which is reduced by 86.7%.The friction coefficient and wear volume of TC4 with HSNT under different loads are always smaller than that of TC4 titanium alloy,and all increase with the increase of load.Under 20 N load,the wear mechanism of TC4 is mainly abrasive wear and oxidative wear,while the wear mechanism of TC4 with HSNT is mainly adhesive wear and oxidative wear.The performance of TC4 titanium alloy with HSNT has been significantly improved,making up for the shortcomings of low hardness and poor wear resistance of TC4.

关 键 词：TC4钛合金 快速渗氮 微观组织 显微硬度 摩擦磨损 

分 类 号：TB331[一般工业技术—材料科学与工程]