N06200镍基合金管板与换热管焊接接头组织与性能研究  

Study on microstructure and mechanical properties of welded joint between N06200 nickel base alloy heat exchange tube and tubesheet

作　　者：武靖伟 王志刚 张建晓 王有银 王岑 张小许 车文斌 朱映宝 徐红 WU Jingwei;WANG Zhigang;ZHANG Jianxiao;WANG Youyin;WANG Cen;ZHANG Xiaoxu;CHE Wenbin;ZHU Yingbao;XU Hong(Lanzhou LS Heavy Equipment Co.,Ltd.,Lanzhou 730314,China)

机构地区：[1]兰州兰石重型装备股份有限公司,兰州730314

出　　处：《压力容器》2023年第4期8-14,共7页Pressure Vessel Technology

摘　　要：采用氩弧焊丝ERNiCrMo-17对换热管(材料为SB-622 N06200)与管板(材料为SB-564 N06200)进行焊接试验。针对此材料的管-板焊接进行焊接工艺研究,通过金相组织观察、角焊缝厚度测量、拉脱力试验、晶间腐蚀试验对N06200镍基合金管板与换热管焊接接头进行分析。结果表明:采用第1层自熔+2层填丝所获得的管-板焊接接头成形良好,焊道均匀饱满;接头的角焊缝厚度均满足标准要求的1.2 mm,接头的拉脱力和晶间腐蚀率均高于管板和换热管母材;接头焊缝组织为胞状晶、柱状树枝晶和等轴晶奥氏体组织,枝晶生长方向随机,等轴晶可抑制热裂纹的产生;接头焊缝区域硬度明显高于其他区域,硬度曲线呈“跳跃”特征。Welding test was carried out on the welded joint between the heat exchange tube(tube material SB-622 N06200)and tubesheet(tubesheet SA-564 N06200)using arc argon welding wire ERNiCrMo-17.The welding process of heat exchange tube-to-tubesheet welding of this material was studied,and the welded joint of N06200 nickel-base alloy tubesheet and heat exchanger tube was analyzed by metallographic microstructure observation,fillet weld thickness measurement,pull-out force test and intergranular corrosion test.The results show that the shape of the obtained tubesheet-to-tube welded joint is good and the weld bead is full using one self-melting layer and two wire filler layers.The fillet weld thickness of the welded joint satisfies the standard requirement of 1.2 mm.The both the pull-out force and corrosion rate of the joint are more than the base material of the heat exchange tube and tubesheet.The microstructure of the joint weld is cellular,columnar dendrite and equiaxed austenite.The growth direction of the columnar dendrite is random,and the equiaxed austenite can inhibit the generation of thermal cracks.The microhardness of weld zone of the joint is higher than that of other zones and the hardness cure shows a“jump”characteristic.

关 键 词：管板-换热管 N06200合金 焊接 微观组织 

分 类 号：TH49[机械工程—机械制造及自动化] TH140.7[一般工业技术—材料科学与工程] TG115.6[金属学及工艺—物理冶金]