深海高抗腐蚀双金属油气管道双钨极热丝TIG堆焊工艺研究  

Double tungsten electrode TIG technology with hot wire for deep-seahigh corrosion resistance bimetal oil and gas pipelines

作　　者：石苏桐 浦娟[1,2] 吴铭方 魏宏兵[3] 郭学文 SHI Sutong;PU Juan;WU Mingfang;WEI Hongbing;GUO Xuewen(School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212100,China;School of Intelligent Manufacturing and Control Engineering,Shanghai Polytechnic University,Shanghai 201209,China;Weihai Wellham Marine Equipment Technology Co.Ltd.,Weihai 264200,China)

机构地区：[1]江苏科技大学材料科学与工程学院,镇江212100 [2]上海第二工业大学智能制造与控制工程,上海201209 [3]山东威尔汉姆海洋装备科技有限公司,威海264200

出　　处：《江苏科技大学学报(自然科学版)》2025年第2期33-38,共6页Journal of Jiangsu University of Science and Technology:Natural Science Edition

摘　　要：双钨极热丝TIG堆焊技术热输入量可控、沉积效率高和稀释率低,在管道内壁堆焊时无刚性固定约束亦能有效保障管道直线度,是一种很有前途的堆焊技术.文中采用双钨极热丝TIG堆焊技术在输油管道高强钢内壁制备两层Inconel 625镍基合金堆焊层,用金相显微镜和扫描电镜对镍/钢堆焊复合板进行微观组织分析,对镍/钢复合板进行硬度测试,并分别在距离镍/钢界面0.5、1.0、1.5 mm处的镍基合金堆焊层取样,进行耐晶间腐蚀性能测试.结果表明:堆焊层的微观结构表现出细胞枝晶结构,沿沉积方向外延生长,枝晶间存在二次相(如Laves相和碳化物);镍/钢堆焊复合板焊态下镍合金堆焊层硬度大于高强钢基板大于钢侧热影响区;试验得出通过钨极热丝TIG堆焊技术得到的堆焊层晶间腐蚀敏感度(degree of sensitization,DOS)值小于1,具有优异的耐晶间腐蚀抗性;随着堆焊层的位置靠近钢侧距离的增加,堆焊层中Fe含量减少,镍基合金堆焊层耐腐蚀性能增加.The double tungsten electrode TIG technology with hot wire has very low welding heat input and very narrow welding heat affected zone,so the welding stress is greatly reduced,and the internal wall welding can effectively guarantee the straightness of the pipeline without rigid fixed constraints,which greatly simplifies the production equipment.It is a promising welding technology.In this study,two layers of Inconel 625 nickel-based alloy surfacing were prepared on the inner wall of high-strength steel in oil pipelines by double tungsten hot wire TIG technology.The microstructure and composition of nickel/steel surfacing composite plate were observed by metallographic microscope and scanning electron microscope,and the hardness test was carried out.The intergranular corrosion resistance of Inconel 625 nickel-based alloy surfacing layers 0.5,1.0 and 1.5 mm away from the nickel/steel interface was tested.The results show that the microstructure of the surfacing layer shows the cell dendrite structure,which grows epitaxially along the deposition direction,and there are secondary phases(such as Laves phase and carbide)between the dendrites.The hardness of nickel alloy surfacing layer of nickel/steel surfacing composite plate is greater than that of high strength steel substrate and than that of heat-affected zone of steel side.The results show that the degree of senstitization(DOS)value of the surfacing layer obtained by double tungsten electrode TIG technology is less than 1,and it has excellent intergranular corrosion resistance.With the increase of the distance between the surfacing layer and the steel side,the Fe content in the surfacing layer decreases,and the corrosion resistance of the nickel-based alloy surfacing layer increases.

关 键 词：双钨极热丝TIG堆焊技术 625镍基合金 微观组织 耐晶间腐蚀性能 

分 类 号：TG455[金属学及工艺—焊接]