感应熔覆原位自生TiC/Ni基复合涂层组织和形成机理  

Microstructure and forming mechanism of TiC/Ni composite coating in situ synthesized by induction cladding

作　　者：王振廷[1] 孟君晟[1] 陈丽丽[1] 周晓辉[1] 

机构地区：[1]黑龙江科技学院材料科学与工程系,黑龙江哈尔滨150027

出　　处：《材料热处理学报》2007年第6期99-103,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金资助项目(50075085);黑龙江省普通高等学校骨干教师创新资助计划项目(1054G046)

摘　　要：采用高频感应熔覆技术，以Ni60A、Ti粉和C粉为原料，在16Mn钢表面原位合成了TiC颗粒增强镍基复合材料涂层。借助扫描电镜、透射电镜、X射线衍射仪、显微硬度计对复合涂层的组织和形成机理进行了分析。结果表明：感应熔敷层组织是由γ-Ni基体、枝晶间共晶组织（γ-Ni＋M23C6）以及弥散分布的TiC颗粒组成。原位生成的TiC颗粒尺寸细小，分布均匀，颗粒大小为0．5～1．0μm。TiC颗粒是由微小八面体堆积而成，其形貌有八面体状和花瓣状。初晶TiC从镍溶液中生长时，由于TiC的生长不受限制，因此初晶TiC长成规则的八面体。当TiC以共晶的方式生长时，由于受到γ-Ni的影响，不可能自由生长，因此共晶TiC长成花瓣状。Ni-based composite coating reinforced by TiC particle was prepared on 16Mn steel by means of induction cladding technique with prealloyed powder of Ni60A ,Ti and C. The microstructure and properties of the coating were investigated by scanning electron microscopy, X-Ray diffraction, transmission electron microscopy and microhardness test, The results show that metallurgical bonding between the coating and 16Mn steel substrate is obtained. The microstructure of the clad coating is mainly composed of γ-Ni,M23C6 and TiC particle which is synthesized in-situ. Most of TiC particles are blocky and some of them are petal shape. TiC particle size is 0.5 - 1.0μm. The particles are dispersivly distributed in the cladded coating. TiC particle is deposited by micro-octahedrons, which is in the shape of octahedron and petal. When alloy temperature drop beneath the liquidus line, primary crystal γ-Ni separates out firstly, with the progress of solidification, the amount of solid phase increases and elements enriched between dendrite, and well-regulated octahedron TiC will separate out when the concentration of Ti and C exceeds saturation level of TiC in liquid phase. The formation of petal shape TiC is the result of eutectic reaction occurred in the last stage of solidification.

关 键 词：感应熔覆 原位自生 涂层 TiC颗粒形貌 

分 类 号：TG162.83[金属学及工艺—热处理] TG174.4[金属学及工艺—金属学]