汽轮机汽蚀叶片YAG激光熔覆镍基合金研究  

YAG laser clad Ni-based alloy on water-eroded steam turbine blades

作　　者：杨胶溪[1] 王喜兵[1] 陈虹[1] 左铁钏[1] 

机构地区：[1]北京工业大学激光工程研究院,北京100022

出　　处：《金属热处理》2008年第10期47-50,共4页Heat Treatment of Metals

基　　金：国家科技计划"973"项目(2006CB605206-3)

摘　　要：用YAG激光器对表面汽蚀的2Cr13钢汽轮机叶片进行修复,采用同步送粉的方式进行自熔性Ni-Cr-B-Si合金粉末的激光熔覆。借助扫描电子显微镜(SEM)和能谱仪(EDS)对激光熔覆层进行组织及成分分析。研究结果表明,激光熔覆层硬度可达45～50 HRC,高于基底材料的硬度(35～40 HRC)。使用YAG固体激光对汽蚀叶片进行修复可以获得与母材冶金结合且无气孔、裂纹等缺陷的熔覆层,其组织主要是γ-Ni、Cr7C3、Ni2B、Ni3B以及少量的Cr2B和Cr3Si。The water eroded steam turbine engine blades were repaired by YAG laser. The coatings were fabricated by laser cladding with direct injection of the Ni-Cr-B-Si powder into the molten pool. Laser clad coatings were characterized by scanning electron microscopy （SEM） and EDS. The results show that the laser cladding coatings have a higher hardness value （45 -50 HRC） compared with that of the substrate material 2Cr13 steel（35 -40 HRC）. The clad layer on the blades can be produced free of pores and cracks by YAG laser. The laser clad Ni-Cr-B-Si alloy coating is mainly a solid solution of γ-Ni with different nickel intermetallics, fundamentally NizB,Ni3 B together with the Chromium carbides Cr7C3 and with lesser proportions of CrzB and Cr3Si.

关 键 词：激光熔覆 汽轮机叶片 针孔 组织结构 

分 类 号：TG174.44[金属学及工艺—金属表面处理]