激光熔覆原位生成Ti(C,N)颗粒强化半钢轧辊熔覆层  

Investigation of in-situ formed Ti(C,N) particle reinforced Fe-based alloy composite coatings on adamite by laser cladding

作　　者：齐勇田[1] 邹增大[1] 王新洪[1] 施瀚超[1] 

机构地区：[1]山东大学材料科学学院,济南250061

出　　处：《焊接学报》2008年第8期69-72,共4页Transactions of The China Welding Institution

基　　金：山东省自然科学基金资助项目(Z2006F07)

摘　　要：以横流CO2激光束作为诱导热源，在铸造半钢轧辊ZUB160CrNiMo基材上形成了含有Ti（C，N）增强粒子的铁基熔覆层，用光镜、扫描电镜、X射线衍射、电子探针等手段对复合熔覆层中增强粒子的成分、形貌和尺寸进行了分析，并采用光学显微硬度计对复合熔覆层的显微硬度进行了测试和分析。结果表明，熔覆前加入的颗粒状TiN在激光熔覆过程中发生了分解，随后分解出的[Ti]又和石墨[C]和[N]分别发生了化合反应，原位生成了新的颗粒状强化相T1（C，N）。在熔覆层中的增强相是以Ti（C0.3N0.7）和Ti（C0.2N0.8）这两种形式存在的。在熔覆层中Ti（C，N）的形貌特征多呈外沿比较光滑、尺寸不等颗粒。颗粒相的大小在0．1～5μm之间，呈弥散分布。熔覆层的显微硬度达到800～900HV0．2。A new method is realized to produce Fe-based alloy composite coating reinforced by Ti(C,N) particle on the substrate named Adamite steel through laser cladding technology. The microstructure of laser cladding layer is analyzed by means of optical microscopy (OM), X-ray diffractionmetry (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and electron probe microscopy analyzer (EPMA). The microhardness of laser cladding layer is measured by microhardness meter. The results show that Ti(C,N) particle is introduced by an in-situ metallurgical reaction of TiN particle and graphite powder during laser cladding process. At the beginning of laser cladding process, TiN particle is decomposed by high laser heat energy, TiN→[Ti]+[N]. At the same time, the new particle named Ti(C0.3N0.7)and Ti(C0.2N0.8) comes into being by the following chemical combination reactions, [Ti]+[C]→TiC,[Ti]+[N]→TiN, xTiC+(1-x)TiN→Ti(CxN1-x). The fine Ti(C,N) particle is dispersed evenly in the matrix. Size of the Ti(C,N) particle is within 0.1-5 mm. The shape of some Ti(C,N)particle is similar to rotundity, and the other is irregular shape. The microhardness of laser cladding layer is distributed within HV0.2 800-900.

关 键 词：碳氮化钛 TiN 原位反应 激光熔覆 半钢轧辊 

分 类 号：TB331[一般工业技术—材料科学与工程]