激光重熔功率对HVOF喷涂WC-Ni涂层耐磨性的影响  

Effect of the Laser Remelting Power on the Wear Resistance of the WC-Ni Coatings Sprayed by HVOF

作　　者：乔振鑫 周平 赵菲[1] 杨睿 李华 QIAO Zhenxin;ZHOU Pin;ZHAO Fei;YANG Rui;LI Hua(College of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan 030024,China;Ningbo Cixi Institute of Biomedical Engineering,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315300,China)

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024 [2]中科院宁波材料技术与工程研究所慈溪医学生物医学工程研究所,浙江宁波315300

出　　处：《材料保护》2024年第11期127-138,共12页Materials Protection

基　　金：山西省基础研究计划资助项目(202303021211195);国家自然科学基金项目(52071329,U23A20627);民用航天技术预先研究项目(D020502);中国科学院青年创新促进会会员(2020299);宁波市“科技创新”2025重大专项(2020Z095);宁波市重点研发计划项目(2023Z195)资助。

摘　　要：为了探究微观组织结构的改变对涂层的硬度和耐磨性的影响,使用低成本的超音速火焰喷涂(HVOF)技术预沉积WC-Ni涂层,并利用50~150 W功率激光重熔后处理涂层,研究了激光重熔功率对WC-Ni涂层的显微组织、物相组成、显微硬度、耐磨损性能的影响。结果表明:采用150 W激光重熔后,涂层中的WC形成了蜂窝状骨架结构,使材料的韧性增强,可以显著抑制裂纹的生成和扩展;当激光功率较低时(50 W和100 W),涂层中并没有形成蜂窝状的骨架结构,但由于激光热作用,原始涂层扁平粒子之间的内聚力增强,硬度和耐磨性都有一定的提高。原始的WC-Ni涂层的硬度平均为327 HV_(0.2),50 W和100 W处理后涂层的硬度分别变为335 HV_(0.2)和346 HV_(0.2)。但150 W处理后的涂层中形成了均匀的蜂窝状WC骨架结构,且有部分WC和Ni形成了Ni4W,故150 W处理后的涂层硬度略有降低(288 HV_(0.2)),不过150 W处理后的涂层中的WC演变成了网状骨架结构,可以良好地抑制裂纹的形成与扩展,其磨损率最低,仅为3.544×10^(-5)mm^(3)/(N·m),相较于WC-Ni涂层[2.025×10^(-4)mm^(3)/(N·m)]、50 W[1.424×10^(-4)mm^(3)/(N·m)]和100 W[1.132×10^(-4)mm^(3)/(N·m)]激光重熔后涂层的磨损率分别降低了83.9%、75.1%和68.7%。蜂窝状WC-Ni结构涂层为开发耐磨材料提供了新的思路。In order to investigate the effect of microstructural changes on the hardness and wear resistance of coatings,low-cost high-velocity oxygen-fuel spraying(HVOF)technology was used to pre-deposit WC-Ni coatings,and the coatings were treated by laser remelting at a power of 50~150 W.The influence of laser remelting power on the microstructure,phase composition,microhardness and wear resistance of WC-Ni coatings was studied.Results showed that after remelted by 150 W laser,the WC in the coating formed a honeycomb like skeleton structure,enhancing the toughness of the material and significantly suppressing the generation and propagation of cracks.When the laser power was low(50 W and 100 W),no honeycomb like skeleton structure was observed in the coating.However,due to the thermal effect of the laser,the cohesion between the flat particles in the original coating was enhanced,and the hardness and wear resistance were improved to some extent.The average hardness of the original WC-Ni coating was 327 HV_(0.2),while the hardness of the coatings after 50 W and 100 W treatment increased to 335 HV_(0.2)and 346 HV_(0.2),respectively.Moreover,after 150 W treatment,a uniform honeycomb like WC skeleton structure was formed in the coating,and some WC and Ni formed Ni_4W,thereby reducing slightly the hardness of the coating after 150 W treatment(288 HV_(0.2)).The WC in the coating treated with 150 W evolved into a mesh like skeleton structure,which could effectively suppress the formation and propagation of cracks,and the wear rate was the lowest,only 3.544×10^(-5)mm^(3)/(N·m),This represented a reduction of 83.9%,75.1%,and 68.7%compared to the wear rates of the original WC-Ni coating[2.025×10^(-4)mm^(3)/(N·m)]and coatings subjected to 50 W[1.424×10^(-4)mm^(3)/(N·m)]and 100 W[1.132×10^(-4)mm^(3)/(N·m)]laser remelting,respectively.Overall,the WC-Ni coatings with honeycomb structure could provide a new approach for the development of wear-resistant materials.

关 键 词：激光表面重熔 超音速火焰喷涂 金属陶瓷涂层 蜂窝结构 摩擦磨损 

分 类 号：TG174.442[金属学及工艺—金属表面处理] TG665[金属学及工艺—金属学]