Ni60/高铝青铜复合涂层定向组织结构特征  

Directional crystal structure characteristics of Ni60/high-aluminum bronze composite coating

作　　者：杨效田[1,2] 段军灵 付小月 巩禄 李文生[1,2] YANG Xiaotian;DUAN Junling;FU Xiaoyue;GONG Lu;LI Wensheng(College of Materials and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学材料科学与工程学院,甘肃兰州730050 [2]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050

出　　处：《哈尔滨工程大学学报》2018年第12期2068-2074,共7页Journal of Harbin Engineering University

基　　金：国家自然科学基金项目(51365024);国家国际科技合作项目(2015DFR51090);兰州理工大学博士基金项目资助

摘　　要：为改善Ni60单一合金涂层的性能,满足苛刻工况的要求,将高铝青铜合金添加到Ni60合金粉体当中,采用高频感应重熔和强制冷却的方法对超音速等离子喷涂的预制涂层进行处理,制备了定向结构的Ni60+5%高铝青铜复合涂层,研究了定向结构复合涂层的微观结构特征、元素分布、物相转变以及对涂层硬度的影响。结果表明:经过高频感应重熔和强制冷却处理,使预制涂层的层流状组织结构成功转变为外延生长的致密的定向结构组织,涂层和基体的结合界面由原来的机械结合转变为牢固的冶金结合。定向结构组织中主枝主要由Ni、Fe元素为主的化合物和固溶体相组成,在其周围包裹有以Cr、C、B构成的析出相,加入高铝青铜的主要元素Cu、Al在定向晶形成过程中和Ni发生反应形成化合物呈网状结构分布在树枝晶主枝杆和析出相之间,起到连接过渡作用。由于定向结构涂层的单向取向特征,表面硬度相对于预制涂层有所降低,但整体均匀性更好。To improve the performance of Ni60 single alloy coatings and make it suitable for severe working conditions,high-aluminum bronze alloy was added to the Ni60 alloy powder.Directional composite coatings of Ni60 and 5%high-aluminum bronze were prepared by high-frequency induction remelting and forced cooling and supersonic plasma spraying.The microstructure,element distribution,phase transformation,and effects of directional structure on coating hardness were studied.The results show that after the high-frequency induction remelting and forced cooling,the laminar structure of the prefabricated coating was transformed to a dense directional structure of epitaxial growth.The bonding type between the substrate and the coating turned from mechanical bonding of prefabricated coatings to metallurgical bonding of directional structured coatings.The main branch of the directional structure was mainly composed of compounds and solid solutions of Ni and Fe,surrounded by precipitated phases of Cr,C,and B.The Al and Cu of high-aluminum bronze reacted with Ni during formation of the directional structure and formed net structure compounds distributed between the main branch and the precipitated phases,bridging the main branch and the precipitated phases.Because of the unidirectional characteristic of the directional structured coating,its surface hardness decreased compared with the prefabricated coatings,but the holistic homogeneity was better.

关 键 词：感应重熔 强制冷却 定向结构 复合涂层 微观结构 元素分布 硬度性能 Ni60/高铝青铜 

分 类 号：TG146[一般工业技术—材料科学与工程]