前置渗氧对TC4钛合金低温等离子复合渗层微观结构和耐磨损性能的影响  

Effect of Pre-Oxidation on Microstructure and WearResistance of Titanium Alloy by Low TemperaturePlasma Oxynitriding

作　　者：王海峰[1,2] 张志明 牛云松[2] 杨延格[2] 董志宏[2] 朱圣龙[2] 于良民[1] 王福会[3] WANG Haifeng;ZHANG Zhiming;NIU Yunsong;YANG Yange;DONG Zhihong;ZHU Shenglong;YU Liangmin;WANG Fuhui(Frontiers Science Center for Deep Ocean Multispheres and Earth System,and Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,China;Shi-changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;Shenyang National Key Laboratory for Materials Science,Northeastern University,Shenyang 110819,China)

机构地区：[1]中国海洋大学、深海圈层与地球系统前沿科学中心和海洋化学理论与工程技术教育部重点实验室,青岛266100 [2]中国科学院金属研究所、师昌绪先进材料创新中心,沈阳110016 [3]东北大学沈阳材料科学国家研究中心东北大学联合研究分部,沈阳110819

出　　处：《金属学报》2023年第10期1355-1364,共10页Acta Metallurgica Sinica

基　　金：国家重点研发计划项目,No.2019YFC0312100;国家自然科学基金项目,No.51701223;民机专项项目,No.MJ-2017-J-99。

摘　　要：针对钛合金硬度低、耐磨性差的缺点,提出了一种由渗氧和氧氮共渗两个过程组成的低温等离子复合渗工艺,并着重研究了前置渗氧对钛合金表面微观结构、物相组成及耐磨性能的影响。利用SEM、TEM、XRD等手段对复合渗层的微观结构和相组成进行了分析,结果表明,等离子复合渗处理的钛合金样品渗层主要由化合物层和扩散层组成,物相为金红石型TiO_(2)和氮化物TiN_(0.26)。采用显微硬度计、纳米压痕仪和往复式摩擦试验机对渗层的显微硬度和摩擦磨损性能进行了表征,结果表明,与传统等离子渗氮相比,等离子复合渗处理可增加渗层的厚度,显著提高钛合金的硬度和弹性模量,大幅改善钛合金的耐磨损性能。Titanium alloys are used in the aerospace industries,chemical industries,biomedicine,marine ships and other fields because of their high strength-to-weight ratio,good corrosion resistance,and biocompatibility.However,titanium alloys have low hardness and poor wear resistance,which limit their applications,especially under sliding contact.Plasma nitriding(PN)is an effective method for improving titanium alloy􀆳s tribological properties.PN can produce a composite layer composed of TiN and Ti_(2)N to improve the friction and wear properties of titanium alloy.However,the high temperature in the nitriding treatment results in a brittle“α-stabilized layer”(a continuous layer ofαphase titanium enriched with interstitial nitrogen atoms)and unfavorable phase transformations in the substrate that can impair the fracture toughness,ductility,and fatigue properties.In this study,a low-temperature plasma-composite treatment,consisting of plasma oxidizing and oxynitriding,has been developed to improve the hardness and wear resistance of Ti-6Al-4V alloy.The effect of the preoxidation process on the surface microstructure,phase composition,and wear performance of titanium alloy was studied.The microstructure and phase composition of the plasma-composite layer were observed using SEM,TEM,XRD,and other methods.The results showed that the composite layer of titanium alloy treated using plasma-compositetreatment is composed of compound and diffusion layers,and the phase is TiO_(2)(rutile)and TiN_(0.26).Microhardness and wear-resistance properties of the composite layer were characterized using microhardness tester,nanoindentation,and reciprocating-friction tester.The plasma-composite treatment can increase infiltration depth of the diffusion layer,surface hardness,elastic modulus,and wear resistance of the titanium alloy more than the traditional nitriding process.

关 键 词：钛合金 等离子渗氮 硬度 等离子渗氧 耐磨 

分 类 号：TG174.4[金属学及工艺—金属表面处理]