激光熔覆纳米Sm_2O_3颗粒增强Ni基合金涂层  

Laser claded Ni-based alloy coatings reinforced by nano-Sm_2O_3 particles

作　　者：李明喜[1] 张世宏[1] 李辉生[1] 何宜柱[1] 

机构地区：[1]安徽工业大学激光加工研究中心,安徽马鞍山243002

出　　处：《焊接学报》2006年第12期5-8,共4页Transactions of The China Welding Institution

基　　金：安徽省教育厅自然科学研究重点项目(2005KJ038ZD;2006KJ071A);安徽省高校金属材料与加工重点实验室资助项目

摘　　要：利用5 kWCO2激光器,在Q235低碳钢表面熔覆微米或纳米Sm2O3/Ni基合金复合材料,制备了涂层。利用光学显微镜、扫描电镜和X射线衍射仪,比较分析了熔覆层的组织及相结构,利用显微硬度计和MM 200型环—块滑动磨损机检测了熔覆层的硬度和耐磨性。结果表明,熔覆层的主要相为γ-Ni和Cr23C6,且出现了Fe7Sm,Ni3Si和Ni3B;加入稀土氧化物熔覆层的冶金结合区白亮带变窄;加入纳米Sm2O3不仅细化了熔覆层的组织,而且形成了大量的等轴晶;加纳米Sm2O3比微米Sm2O3的熔覆层的显微硬度和相对耐磨性大幅度提高,磨损机理由磨粒磨损和黏着磨损转变为微动磨损。Ni-based alloy coatings with nano/micro-Sm_2O_3 particles addition produced by a 5 kW CO_2 laser on Q235 low carbon steel were introduced.Cross-section of the coatings was examined to reveal their microstructure using optical microscope,scanning electron microscope,and X-ray diffraction instrument.The hardness and wear resistance were measured with microhardness tester and MM200 type sliding wear machine.The results showed that γ-Ni and Cr_(23)C_6 exist in the coatings.Fe_7Sm,Ni_3Si and Ni_3B are also found by adding nano-Sm_2O_3.Fine microstructure and equiaxed dendrite are observed with nano-Sm_2O_3 addition.A thin layer of metallurgical bonding,the white and bright strip,is observed by adding the rare earth oxide.The hardness and wear resistance of the coatings with nano-Sm_2O_3 addition are better than that with micro-Sm_2O_3.The mechanism was found from abrasive/adhesive wear to fretting wear.

关 键 词：激光熔覆 纳米Sm2O3 组织结构 显微硬度 耐磨性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]