不同高温时效时间下TP347H/12Cr1MoV异种钢接头的组织和力学性能  

Microstructure and Mechanical Properties of TP347H/12Cr1MoV Dissimilar Steel Welded Joints with Different High Temperature Aging Time

作　　者：韩哲文[1] 王智春[1] 康举[1,2] 信瑞山 王启冰 沈宇辰 冯含 曾燕屏 HAN Zhewen;WANG Zhichun;KANG Ju;XIN Ruishan;WANG Qibing;SHEN Yuchen;FENG Han;ZENG Yanping(North China Electric Power Research Institute Co.,Ltd.,Beijing 100045,China;Beijing Key Laboratory of Pipeline Critical Technology and Equipment for Deepwater Oil&Gas Development,Beijing Institute of Petrochemical Technology,Beijing 102617,China;Ansteel Beijing Research Institute Co.,Ltd.,Beijing 102211,China;School of Materials Science&Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]华北电力科学研究院有限责任公司,北京100045 [2]北京石油化工学院深水油气管线关键技术与装备北京市重点实验室,北京102617 [3]鞍钢集团北京研究院有限公司,北京102211 [4]北京科技大学材料科学与工程学院,北京100083

出　　处：《热加工工艺》2022年第22期116-122,125,共8页Hot Working Technology

基　　金：国家重点实验室开放课题研究基金资助项目(AWJ-21M13);北京市重点实验室开放课题资助项目(BIPT2020003);华北电力科学研究院有限责任公司科技项目(KJZ2019097);大学生研究训练计划项目(2019J00028,2020J00035)。

摘　　要：以镍基焊丝为填充金属,采用TIG焊对TP347H/12Cr1MoV异种钢进行焊接,在650℃下对异种钢接头进行不同时间时效处理。在测试了时效后接头高温拉伸性能的基础上,分析了接头12Cr1MoV钢侧粗晶区和熔合区的微观组织及析出相特点,测定了熔合线附近的碳浓度分布。结果表明:时效不同时间的异种钢接头高温拉伸均断在12Cr1MoV侧。随时效时间的增加,接头的抗拉强度和屈服强度逐渐降低;时效前12Cr1MoV钢母材由等轴铁素体晶粒和少量珠光体组成,随时效时间的增加,珠光体中的碳化物逐渐球化,并向铁素体晶界迁移,在晶界链接成串或呈条带状分布;不同时效时间接头12Cr1MoV钢侧粗晶区的金相组织差别不大,为铁素体+回火组织;时效前12Cr1MoV钢侧熔合线已聚集了大量呈条带状分布的析出相,随时效时间的增加,析出相尺寸增大、条带变宽。TP347H/12Cr1MoV dissimilar steel was welded with nickel-based welding wire as filler metal by TIG welding, and then the joints were subjected to different aging treatments at 650 ℃. After measuring the high temperature tensile properties of the aged joints, it was comprehensively analyzed that the microstructure of the coarse-grained zone and fusion zone on the side of 12Cr1MoV steel and the characteristics of the precipitated phases, and also the distribution of carbon concentration near the fusion line. The results show that the tensile strength and yield strength for the dissimilar steel joints gradually decrease as the aging time increases, and all the aged joints have eventually fractured on the 12Cr1MoV side after high-temperature tensile tests. The base metal of 12Cr1MoV steel before aging treatment is composed of equiaxed ferrite grains and a small amount of pearlites. With increasing the aging time, the carbides in pearlite structure gradually spheroidized and migrated to the ferrite grain boundaries in which linked in clusters or distributed in strips. The metallographic structure of the coarse-grained heat-affected zone on the 12Cr1Mo V steel side for different aged joints has no much difference,and is mainly composed of ferrite and tempered structure.The fusion line on the 12Cr1MoV steel side has gathered a large number of precipitated phases distributed in strips after welding. The size of the precipitated phases increase significantly and the strips become wider during high temperature aging treatment.

关 键 词：异种钢焊接接头 铁素体耐热钢 镍基焊缝 微观组织 高温力学性能 

分 类 号：TG156.92[金属学及工艺—热处理]