激光熔覆NiCrMo和NiCrBSi涂层的微观组织及摩擦学性能研究  

Microstructure and Tribological Properties of Laser Cladding NiCrMo and NiCrBSi Alloy Coatings

作　　者：曹四龙 王凌倩[1] 周健松[1] CAO Si-long;WANG Ling-qian;ZHOU Jian-song(State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院兰州化学物理研究所固体润滑国家重点实验室,甘肃兰州730000 [2]中国科学院大学材料与光电研究中心,北京100049

出　　处：《材料保护》2021年第3期1-8,33,共9页Materials Protection

摘　　要：目前有关NiCrMo合金涂层的高温摩擦学行为和机理研究鲜有报道。为此,利用激光熔覆技术制备了NiCrMo涂层,以研究较广泛、应用较深入的NiCrBSi合金涂层作为对照,通过X射线衍射仪、扫描电镜和Raman光谱仪对涂层的物相组成、微观结构和磨痕形貌、成分进行分析,研究了室温~800℃下2种镍基合金涂层的主要磨损机理。结果表明:NiCrMo合金涂层的微观结构主要由单一的γ-Ni固溶体形成的细小树枝晶组成。NiCrBSi合金涂层中较多含量的B、Si和C小原子主要以Cr7C3硬质相和Ni-B-Si共晶组织的形式分布于γ-Ni固溶体中。在室温~400℃时,NiCrMo合金涂层发生严重的磨粒磨损和塑性变形,NiCrBSi合金涂层具有更高的显微硬度和抗塑性变形能力,因而表现出更优异的耐磨性。当温度超过400℃时,Cr_(7)C_(3)硬质相和Fe_(2)O_(3)的疲劳脱落形成的硬质颗粒加剧了对氧化膜的切削破坏,导致NiCrBSi合金涂层在高温条件下发生严重的磨粒磨损,而NiCrMo合金涂层磨痕表面大量的金属氧化物以及NiMoO_(4)复合物能够形成连续致密的氧化釉质层起到减摩抗磨的作用,因此具有更好的高温耐磨性。At present,there are few reports on the high temperacture tribological behavior and mechanism of NiCrMo alloy coatings,for this,NiCrMo and NiCrBSi alloy coatings were prepared by laser cladding technology.The NiCrBSi alloy coatings,which were widely studied and widely used,were used as a contrast.The phase composition,microstructure,worn morphology and composition of the coatings were analyzed by X-ray diffraction,scanning electron microscopy and Raman characterization.The main wear mechanism of this two coatings was investigated from room temperature to 800℃.Results showed that the microstructure of NiCrMo alloy coating was mainly composed of fine dendrites formed by a single γ-Nisolid solution.The small atoms B,Si and C in NiCrBSi alloy coating were mainly distributed in γ-Nisolid solution in the form of Cr_(7)C_(3) hard phase and Ni-B-Si eutectic structure.From room temperature to 400℃,NiCrMo alloy coating had serious abrasive wear and plastic deformation.NiCrBSi alloy coating possessed higher microhardness and plastic deformation resistance,committing to better wear resistance.When the temperature was over 400℃,the hard particles formed by fatigue shedding of Cr_(7)C_(3) hard phase and Fe_(2)O_(3) aggravated the cutting damage to the oxide film,which led to serious abrasive wear of NiCrBSi alloy coating under high temperature.However,a large amount of metal oxides and NiMoO4 complex on the worn surface of NiCrMo alloy coating could form a continuous and compact oxide enamel film,which reduced the friction and wear rate,and thus NiCrMo alloy exhibited better wear resistance at high temperature.

关 键 词：NiCrMo合金涂层 NiCrBSi涂层 微观组织 力学性能 高温摩擦学性能 

分 类 号：TG665[金属学及工艺—金属切削加工及机床]