Mo含量对激光熔覆CoCrW涂层摩擦磨损行为的影响  

Effect of Mo Content on the Friction and Wear Behavior of Laser Cladding CoCrW Coating

作　　者：罗兰 路世盛 胥卫奇 文泽东 王凌倩[1] 周健松[1,2] LUO Lan;LU Shisheng;XU Weiqi;WEN Zedong;WANG Lingqian;ZHOU Jiansong(Key Laboratory of Science and Technology on Wear and Protection of Materials,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,中国科学院材料磨损与防护重点实验室,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：《表面技术》2025年第3期90-100,共11页Surface Technology

基　　金：中国科学院战略性先导科技专项(XDB 0470302);中国科学院材料磨损与防护重点实验室青年基金(SYSQY-2023-1)。

摘　　要：目的考察不同含量的Mo元素对激光熔覆CoCrW涂层摩擦磨损行为的影响。方法采用激光熔覆技术制备不同Mo含量的CoCrW涂层,利用扫描电子显微镜、能谱分析仪和X射线衍射仪分析涂层的物相及元素组成,通过显微硬度计和高温摩擦试验机测试并分析涂层的硬度和摩擦学性能。结果不同Mo含量的熔覆层与基材均为冶金结合,涂层组织均匀致密,熔覆层主要由γ-Co和碳化物组成。在激光熔覆过程中,涂层的微观组织结构由中部粗大的树枝晶组织逐渐转变为表面尺寸较小的柱状晶和胞状晶组织。碳化物相的含量随着涂层中Mo含量的增大而增大,显微硬度也随之增加。当涂层中Mo的质量分数为30%(M3涂层)时,显微硬度达到最大值(954HV0.2)。在往复摩擦条件下,与Si3N4对磨时,随着温度的升高,4种涂层的摩擦因数和磨损率均表现出先升高后降低的趋势。在常温下,涂层以磨粒磨损为主。在400℃下,黏着磨损加剧。随着温度的升高,磨痕表面氧化物逐渐增多,在600~800℃下氧化釉质层逐渐形成,并致密化,改善了涂层的摩擦学性能。其中,M3涂层(Mo的质量分数为30%)在室温至高温范围内的耐磨性能最优异。结论随着Mo含量的增加,在固溶强化和弥散强化的协同作用下,激光熔覆层的硬度和摩擦学性能显著提高。在高温下,Mo元素促进了氧化釉质层的形成和致密化,对涂层的摩擦学性能改善更为明显。As a new type of green surface modification technology,laser cladding uses high-energy laser beam to prepare high-performance coatings on the metal surface.Compared to other technologies,the coatings prepared by laser cladding technology show a higher bonding to the substrate.Adding different elements in powder can further enhance the mechanical properties and oxidation and wear resistance of the laser cladding coatings.Among the alloying elements,Mo element can improve the high temperature strength and corrosion resistance of alloys.The work aims to prepare CoCrW coatings with different Mo contents(≥10%)by laser cladding technology,and systematically investigate the effects of different Mo contents(0%,10%,20%and 30%)on the microstructure,mechanical properties,and tribological properties of the coatings.GH4169 was selected as the substrate materials and ground by sandpaper.Different contents(0%,10%,20%and 30%mass fraction)of Mo were added in CoCrW as a cladding powder.4 kW fiber laser(YLS-4000)was used for laser cladding of pre-positioned powder.During the cladding process,the laser power was 1.4 kW,the scanning speed was 800 mm/min,the spot diameter was 4 mm,the overlap rate was 50%,and the powder thickness was 2.5 mm.The sample was cut by wire cutting,the cross section was polished and corroded with HCl(2 mL)+C2H5OH(2 mL)+CuCl2(0.1 g)solution.Scanning electron microscope(JEOL JSM-5600LV),energy disperse spectroscope(JSM-5600LV)and X-ray diffraction(PANalytical Empyrean)were adopted to evaluate the physical phase and elemental composition,and Vickers hardness measurement(MH-5-VM)and friction testing machine(Rtec-3000F)were utilized to assess and evaluate the hardness distribution and tribological properties of the coatings.The coatings showed a uniform and dense microstructure and formed a metallurgical bond to the substrate.Co-based coatings were mainly composed ofγ-Co and carbide phase.During the laser cladding process,the microstructure of the coatings gradually transformed from the large dendrite in the m

关 键 词：激光熔覆 CoCrW Mo含量 摩擦学性能 磨损机制 

分 类 号：TG174.4[金属学及工艺—金属表面处理]