TiB_2对Ni基合金激光熔覆层组织与性能的影响  

Effect of TiB_2 on microstructure and properties of Ni-based alloy coating by laser cladding

作　　者：袁晓敏[1] 龚佑品[1] 何宜柱[1] 

机构地区：[1]安徽工业大学安徽省高校金属材料与加工重点实验室,安徽马鞍山243002

出　　处：《焊接学报》2007年第5期41-44,共4页Transactions of The China Welding Institution

基　　金：安徽省教育厅自然科学与研究基金资助项目(2005KJ225)

摘　　要：采用5kWCO2激光器在低碳钢表面熔覆Ni基合金层及TiB2/Ni基合金金属陶瓷涂层,研究了两种涂层的组织、显微硬度以及滑动磨损特性。结果表明,Ni基合金层主要组成相为γ-(Ni,Fe),Cr23C6等,TiB2/Ni基合金复合涂层组成相主要有γ-(Ni,Fe),Ni3B,TiB2和TiC等;Ni基合金层由发达γ-(Ni,Fe)枝晶和其间共晶组织所组成,TiB2/Ni基合金复合涂层典型组织为等轴固溶体以及其间细小共晶组织;TiB2对熔覆层的组织有显著的影响,使熔覆层组织细化,并由树枝晶转变为等轴晶;加入TiB2可显著提高Ni基合金涂层的显微硬度及耐磨性能。Ni-base alloy and TiB2/Ni-based alloy metal-ceramics coatings were obtained on low carbon steel surface by 5 kW CO2 laser.Microstructure,phases,microhardness and sliding wear resistance of the coatings were studied.The results shown that Ni-based alloy coating consists of γ-(Ni,Fe),Cr23C6 etc and TiB2/Ni-based alloy composite coating consists of γ-(Ni,Fe),Ni3B,TiB2 and TiC and so on.The Ni-based alloy coating is made up of flourishing γ-(Ni,Fe)dendrite and eutectic structure.Equiaxed solid solution and fine eutectic structure are observed in the TiB2/Ni-based alloy composite coating.The influence of TiB2 ceramics on microstructure of coating is prominent that the microstructure of coating is finer and the dendrite crystal gradually becomes equiaxed grain.The microhardness and wear resistance of Ni-based alloy can be improved remarkablely by adding TiB2.

关 键 词：激光熔覆 NI基合金 TIB2 金属陶瓷涂层 显微组织 

分 类 号：TG156.99[金属学及工艺—热处理]