W_xC增强镍基合金等离子堆焊层组织与空蚀性能  

Microstructure and cavitation erosion performance of W_xC reinforced Ni-base alloy composite coating by plasma transferred arc welding

作　　者：刘舜尧[1] 张松[1] 崔文东[2] 张春华[1] 吴臣亮 孙足来 

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870 [2]沈阳鼓风机集团核电泵业有限公司,沈阳110869 [3]沈阳真空技术研究所,沈阳110042

出　　处：《焊接学报》2017年第4期39-42,共4页Transactions of The China Welding Institution

基　　金：国家重点研发计划资助项目(2016YFB1100204;2013ZX06002-002);国家自然科学基金资助项目(51271126);沈阳市科技计划资助项目(F16-032-0-00)

摘　　要：采用等离子堆焊技术在316L不锈钢表面原位合成W_xC增强镍基复合材料涂层,对涂层显微组织、相组成、硬质增强相的分布、显微硬度以及空蚀性能进行了分析.结果表明,Colmonoy 88合金等离子堆焊成形性良好,组织致密;堆焊层组织主要由γ-Ni固溶体,原位合成多角形、颗粒状W_xC及少量的Cr7C3,Fe3W3C,Cr B2相组成.堆焊过程中,熔池温度低于1 655 K时,原位生成WC和W2C,温度高于1 655 K时,原位生成的WC发生了分解.镍基合金堆焊层平均硬度可达1 619 HV,为基材的8倍以上,在3.5%Na Cl溶液中镍基复合材料抗空蚀性能为316L不锈钢基材的5倍.In-situ synthesis of W_xC particle reinforced Nibase composite coating was synthesized on 316L stainless steel by plasma transferred arc welding.Microstructure,phase constitent,the distribution of reinforced particle,microhardness and cavitation erosion property were investigated by using SEM,EDS,XRD,microhardness tester and ultrasonic vibrator,respectively.Results indicate that Colmonoy 88 coating exhibits a perfect plasma hardfacing tracks and the microstructure is dense.When the molten pool temperature is below 1 655 K,WC and W_2C reinforced particles are in situ synthesized during the melting process.When the molten pool temperature is higher than 1 655 K,the in situ synthesized WC particles are dissolved.The phase constituents of the coating are mainly composed ofγ-Ni solid solution,in-situ synthesized W_xC particles and a small amount of Cr_7C_3,Fe_3W_3C and CrB_2.The average microhardness of the coating is 1 619 HV,which is 8 times than that of the substrate.The cavitation erosion resistance of the Ni based composite material is 5 times than that of the substrate in 3.5% NaCl solution.

关 键 词：等离子堆焊 镍基合金 原位合成WxC 空泡腐蚀 

分 类 号：TG455[金属学及工艺—焊接]