作　　者： ; ; ; ;

机构地区： 山东大学材料科学与工程学院材料液态结构及其遗传性教育部重点实验室

出　　处： 《焊接学报》 2016年第11期39-42,共4页

摘　　要： 以Ni35自熔性合金粉末为熔覆材料,采用激光熔覆技术在锆合金表面原位生成了NiZr_2/陶瓷增强镍基涂层.利用金相显微镜、扫描电镜、X射线衍射仪等对熔覆界面附近的微观组织、物相组成及界面结合特征进行分析.结果表明,熔覆层基体组织为NiZr+Ni_(10)Zr_7,增强相NiZr_2以细针状均匀分布在熔覆层上部和底部,块状及棒状的陶瓷相Zr_5(Si_xNi_(1-x))_4/Zr(Si_xNi_(1-x))分布在熔覆层中部,熔覆层与基体间实现良好的熔焊冶金结合,界面结合区组织不均匀,分布有等轴状NiZr及晶间的α-Zr,熔覆层的显微硬度分布均匀,平均值约为1 100 Hv. The NiZr_2/ceramic reinforced Ni-based composite coating was in-situ synthesized by laser cladding using Ni35 self-fluxing powder on zirconium alloy substrate. The microstructure,phase constituents and interfacial characteristics were investigated by optical microscope,scanning electron microscope and X-ray diffraction method. Results indicated that the matrix of coating was mainly composed of NiZr + Ni_(10)Zr_7,fine needles NiZr_2 distributed at the top and the bottom,and blocky Zr_5( Si_xNi_(1-x))_4/Zr( Si_xNi_(1-x)) ceramic phase in the middle of the coating. Good metallurgical bonding between substrate and coating was obtained. Heterogeneous microstructure of interface zone was mainly compromised of equiaxial NiZ r phase and α-Zr at the grain boundary. The mean value of microhardness of the coating reached 1 100 HV.

关 键 词： 锆合金 激光熔覆 增强相 微观组织 界面特征

领　　域： [金属学及工艺] [金属学及工艺]