增材制造Co-Cr-W合金修复QT400-18球墨铸铁发动机机体的抗穴蚀性能研究  

Research on Cavitation Erosion Resistance of QT400-18 Ductile Iron Engine Block Repaired by Additive Manufacturing with Co-Cr-W Alloy

作　　者：肖宇枫 魏翔宇 张峰 高俊杰 孙兵兵 XIAO Yufeng;WEI Xiangyu;ZHANG Feng;GAO Junjie;SUN Bingbing(AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;The Company Profile of HFYC(Zhenjiang)Additive Manufacturing Co.,Ltd.,Zhenjiang 212132,China)

机构地区：[1]中国航发北京航空材料研究院,北京100095 [2]航发优材(镇江)增材制造有限公司,江苏镇江212132

出　　处：《热加工工艺》2024年第20期110-115,122,共7页Hot Working Technology

基　　金：国家自然科学基金项目(52101058)。

摘　　要：为提高球墨铸铁发动机机体的表面性能,解决使用过程中空泡溃灭产生的穴蚀问题,分别采用激光熔覆和氩弧焊在QT400-18球墨铸铁表面进行Co-Cr-W钴基合金层的增材修复,并对熔覆层和堆焊层试样的组织、硬度、室温拉伸性能、抗穴蚀性能进行分析。结果表明:修复层主要为细小的、交错生长的柱状晶和树枝晶,激光熔覆层的组织比氩弧焊层组织更细密,硬度更高;这两种修复层试样的抗拉强度和基体接近,但塑性下降;经8 h穴蚀后,QT400-18基体损伤严重,激光熔覆试样和氩弧焊试样的表面较光滑,其抗穴蚀性能明显提高,激光熔覆试样和氩弧焊试样的失重相比球墨铸铁基体分别降低95.32%、93.58%。In order to improve the surface performance of ductile iron engine block and solve the problem of cavitation erosion caused by bubble collapse during use,laser cladding and argon arc welding were used to repair the surface of QT400-18 ductile iron,respectively.The microstructure,hardness,room temperature tensile performance and cavitation erosion resistance of the laser cladding layer and argon arc welding layer samples were analyzed.The results show that the repaired layers are mainly composed of small,staggered columnar crystals and dendritic crystals.The microstructure of the laser cladding layer is finer and harder than that of the argon arc welding layer.The tensile strengths of the two repaired layer samples are close to that of the matrix,but the plasticity decreases.After 8 h of cavitation erosion,the QT400-18 substrate is severely damaged,the laser cladding and argon arc welding samples have smoother surface,and the cavitation erosion resistance is obviously improved.Compared with that of QT400-18 substrate,the wear mass loss of the laser cladding and argon arc welding samples decreases by 95.32%and 93.58%,respectively.

关 键 词：钴基合金 QT400-18 穴蚀 激光熔覆 氩弧焊 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TG455[金属学及工艺—金属学]