La2O3改性Ti/MoS2镍基复合涂层微观组织和摩擦学性能研究  

Microstructure and Tribological Properties of La2O3 Modified Ti/MoS2 Nickel-based Composite Coatings

作　　者：韩雪 刘金娜 崔秀芳 卢熙群[2] 金国 HAN Xue;LIU Jin-na;CUI Xiu-fang;LU Xi-qun;JIN Guo(Key Laboratory of Ultra Light Materials and Surface Technology under the Ministry of Education,School of Materials Science and Chemical Engineering,Harbin Engineering University,Harbin 150001,China;School of Power and EnergyEngineering,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学材料科学与化学工程学院超轻材料与表面技术教育部重点实验室,哈尔滨150001 [2]哈尔滨工程大学动力与能源工程学院,哈尔滨150001

出　　处：《表面技术》2019年第9期167-176,共10页Surface Technology

基　　金：国家自然科学基金资助项目(51575118)~~

摘　　要：目的为提升Ni60A+Ti/MoS2复合涂层的力学性能和摩擦学性能。方法利用激光熔覆技术在HT270灰铸铁表面制备了La2O3改性镍基自润滑复合涂层,通过硬度测试、摩擦磨损实验、XRD测试分析和扫描电镜分析,对比分析了La2O3添加量对复合涂层的微观组织、相组成、显微硬度和室温及200℃条件下摩擦学性能的影响。结果La2O3改性后的涂层主要由CrNiFeC、NiTi、(Fe,Cr)7C3、Cr7C3、TiC、Ti2CS、MoS2相和La2O3组成。添加La2O3后可以明显细化晶粒,使组织更加均匀致密,提高了熔覆层显微硬度及耐磨性。当La2O3的添加量为1.0%时,涂层的硬度值最高达776HV0.2。La2O3改性后,涂层的摩擦学性能也得到了优化。室温时,1.0%La2O3涂层的磨损失重仅为1.8mg,摩擦系数为0.48,与未添加La2O3的涂层相比,磨损失重降低了47.1%,摩擦系数也明显降低;200℃高温磨损时,1.0%La2O3涂层的磨损失重降低了41.3%,摩擦系数降低到0.50。结论La2O3的加入可以有效提高涂层的减摩性和耐磨性等摩擦学性能,同时还能优化涂层的组织结构和硬度等力学性能。采用激光熔覆技术制备的La2O3改性镍基涂层,力学性能和摩擦学性能得到有效提高。The work aims to improve the mechanical properties and tribological properties of Ni60A+Ti/MoS2 composite coating.La2O3 modified nickel-based self-lubricating composite coating was prepared on the surface of HT270 gray cast iron by laser cladding technology.The effects of La2O3 amount on microstructure,phase composition,microhardness and tribological properties at room temperature and 200 ℃ were analysed by hardness test,friction and wear test,XRD test and SEM.The La2O3 modified coating was mainly composed of CrNiFeC,NiTi,(Fe,Cr)7C3,Cr3C7,TiC,Ti2CS,MoS2 phases and La2O3.After La2O3 was added,the grains were refined and the structure was more uniform and dense.The microhardness and wear resistance of the cladding layer were improved.When the addition amount of La2O3 was 1.0%,the hardness of the coating was up to 776HV0.2.The tribological properties of the coating after La2O3 modification were also optimized.The 1.0% La2O3 coating had grinding loss of only 1.8 mg and friction coefficient of 0.48 at room temperature.Compared with the coating without La2O3,the weight loss was reduced by 47.1%,and the friction coefficient was also significantly reduced.The wear loss of 1.0% La2O3 coating was reduced by 41.3% and the friction coefficient was reduced to 0.50 at 200 ℃.The addition of La2O3 can effectively improve the tribological properties of the coating,such as wear reduction and wear resistance and also optimize the mechanical properties,such as the structure and hardness.La2O3 modified Ni-based coatings prepared by laser cladding can effectively improve the mechanical and tribological properties of composite coatings.

关 键 词：镍基合金 激光熔覆 LA2O3 自润滑涂层 摩擦学性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]