P110套管内壁CMT/P堆焊Inconel 625合金的组织及性能研究  

Research on the Microstructure and Properties of Inconel 625 Alloy by CMT/P Overlay Welding on the Inner Wall of P110 Casing

作　　者：徐连勇[1,2] 王成 杨连河 赵雷 荆洪阳[1,2] 韩永典 XU Lianyong;WANG Cheng;YANG Lianhe;ZHAO Lei;JING Hongyang;HAN Yongdian(School of Materials Science and Engineering,Tianjin University,Tianjin 300350;Tianjin Key Laboratory of Modern Connection Technology,Tianjin 300350;CNOOC(Tianjin)Pipeline Engineering Technology Co.,Ltd.,Tianjin 300456)

机构地区：[1]天津大学材料科学与工程学院,天津300350 [2]天津市现代连接技术重点实验室,天津300350 [3]中海油(天津)管道工程技术有限公司,天津300456

出　　处：《机械工程学报》2023年第14期159-168,共10页Journal of Mechanical Engineering

摘　　要：针对P110油套管,采用冷金属过渡加脉冲的焊接工艺获得了平整、连续、无缺陷的Inconel 625合金堆焊层。借助体视显微镜、金相显微镜、SEM、EDS、XRD、TEM、碳硫仪等对堆焊层的成分及微观组织进行了分析。堆焊层组织从熔合线到堆焊层顶部依次为柱状晶、树枝晶、等轴晶,基体为Ni的固溶体,其上分布着Laves和MC型碳化物。堆焊层含有从母材扩散来的C、Fe等元素。采用双环电化学动电位再活化方法对堆焊层的耐腐蚀性进行了研究,发现随着C、Fe的扩散会降低其耐晶间腐蚀抗性。通过EBSD还发现,小角度晶界(具有<15o的晶粒取向)和特殊的大角度晶界(Σ≤29)中的Σ3n晶界(低Σ重合点阵,n=1,2,3)的提高,会提高晶间腐蚀耐性。结果表明采用合适的工艺参数进行Inconel 625合金的堆焊,可得出无明显缺陷,成形良好且具有良好耐腐蚀性能的堆焊层。For P110 oil casing,the forming good and defect-free Inconel 625 alloy cladding layer was obtained by the cold metal transition plus pulse welding process.The composition and microstructure of the cladding layer were analyzed with the Smartzoom,Metallurgical Microscope,SEM,EDS,XRD,TEM,Carbon Sulfur Analyzer,etc.The structure of the cladding layer is columnar,dendritic,and equiaxed from the fusion line to the top of the cladding layer.The matrix is a solid solution of Ni with Laves and MC carbides distributed inside it.The cladding layer contained C and Fe diffused from the base material.The double-loop electrochemical dynamic potential reactivation method was used to study the corrosion resistance of the cladding layer,which indicates that the diffusion of C and Fe will reduce the resistance to intergranular corrosion.EBSD analysis showed that the improvement of the low-angle grain boundaries(with a grain orientation of<15o)andΣ3n boundaries in the special high-angle grain boundaries(Σ≤29),(lowΣcoincidence lattice,n=1,2,3)will improve the resistance to intergranular corrosion.The results showed that the cladding of Inconel 625 alloy with suitable process parameters can obtain a cladding layer with no obvious defects,good weld formation,and good corrosion resistance.

关 键 词：CMT/P焊接 P110 Inconel 625堆焊 微观组织 腐蚀性能 

分 类 号：TG156[金属学及工艺—热处理]