激光熔覆再制造镍基高温合金气门的组织和性能研究  

Microstructure and properties of nickel based superalloys valve by laser cladding remanufacturing

作　　者：郑子云[1] 马冰[1] 依颖辉[1] 郭昌明[2] 冯胜强[1] 刘光[1] 潘力平[1] 

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315103 [2]中国北方发动机研究所,山西大同037036

出　　处：《兵器材料科学与工程》2013年第3期101-104,共4页Ordnance Material Science and Engineering

基　　金：浙江省国际科技合作专项项目(2012C24011);宁波市国际合作项目(2010D10014);宁波市国际合作攻关项目(2011D10008);宁波市工业攻关项目(2012B10009)

摘　　要：采用激光熔覆技术对磨损失效的Nimonic 80A气门进行修复。利用金相显微镜观察熔覆层组织,用扫描电镜和能谱仪对熔覆层进行组织和成分分析,研究熔覆层硬度的变化,采用渗透探伤检测熔覆层表面缺陷,对合格的再制造气门进行装机考核实验。结果表明:激光熔覆层组织主要由柱状树枝晶和枝晶间的共晶组织组成,熔覆层和基体之间形成冶金结合,熔覆层内部无气孔和微裂纹等缺陷;熔覆层平均硬度较基体提高了37.7%;再制造气门的耐磨性是新气门的1.5倍。The worn Nimonic 80A valve was repaired by laser cladding. Metallurgical microscope,SEM,EDS and penetrant inspection test were used to analyze the microstructure and composition of the cladding layer. The microhardness of cladding layer was measured by Vicker hardness tester. Meanwhile,the experiment of trial run was conducted with the qualified remanufactured valve. Results show that the cladding layer consists of columnar dendrite and interdendritic eutectic structure. The bond between the cladding layer and substrate is mainly metallurgical,and there are no internal defects,such as blowholes and microcracks,in the cladding layer. The average microhardness of the cladding layer is 37.7% higher than that of substrate, and the wear resistance is 1.5 times greater than that of the new valve.

关 键 词：激光熔覆 Nimonic 80A 气门 再制造 

分 类 号：TG156.99[金属学及工艺—热处理]