原位生成WB-CrB增强镍基激光熔覆层  

In-Situ Synthesis of WB-CrB Reinforced Ni-Based Coatings by Laser Cladding

作　　者：杨文超[1] 晁明举[1] 孙艳敏[1] 杨宁[1] 田得雨[1] 

机构地区：[1]郑州大学物理工程学院材料物理教育部重点实验室,河南郑州450052

出　　处：《激光与光电子学进展》2010年第8期80-85,共6页Laser & Optoelectronics Progress

基　　金：河南省教育厅自然科学研究计划基金(2006140009)资助课题

摘　　要：采用激光熔覆技术,在45#钢表面制备原位生成WB-CrB颗粒增强镍基复合涂层。使用X射线衍射仪(XRD)、金相显微镜、扫描电镜(SEM)和能量色散谱(EDS),对熔覆层的显微组织和物相构成进行分析,并对硬度、摩擦性能进行测试。结果表明,在适当工艺条件下,原位生成WB-CrB颗粒增强镍基涂层形貌良好,涂层与基材呈冶金结合。熔覆层底部组织为定向生长的γ(NiFe)树枝晶,熔覆层中上部组织为WB-CrB颗粒相,均匀分布于γ(NiFe)树枝晶基体中。熔覆层具有较高的硬度(平均硬度HV0.31350)和良好的耐磨性,其摩损失重仅为纯Ni60熔覆层的1/7。大量WB-CrB复合颗粒的形成及其在涂层中的均匀弥散分布是熔覆层硬度和耐磨性提高的主要原因。The in-situ WB-CrB reinforced Ni-based composite coating is synthesized by laser cladding on steel 45# by prior to pasting.The microstructure and phase analyses are performed by X-ray diffractometer（XRD）,optical microscope,scanning electron microscopy（SEM） and energy dispersive spectroscopy（EDS）.The microhardness and tribological properties of the coatings are also investigated.The results indicate that the coating epitaxial growing from the substrate with excellent bonding between the coating and substrate is ensured by the strong metallurgical interface.The microstructure at the bottom of the cladding layer mainly consists of orients dendrites of γ（NiFe）.The microstructure at the middle and upper zones contains WB-CrB particles dispersed in the matrix of γ（NiFe）.Compared with a pure Ni60 coating,the hardness of the WB-CrB complex particulate-reinforced composite coating is enhanced to HV0.31350.The wear and tear mass loss in a block on ring test against hardened steel is reduced by a factor of seven.This can be attributed to the presence of in-situ synthesized WB-CrB complex particles and their well distribution in the coating.

关 键 词：激光熔覆 原位生成WB-CrB 显微组织 耐磨性 

分 类 号：TN249[电子电信—物理电子学] TG665[金属学及工艺—金属切削加工及机床]