T91/TP347H异种钢焊接接头服役过程显微组织研究  

Study on Microstructure of T91/TP347H Dissimilar Steel Welded Joints in Service

作　　者：李敏 邓守浩 刘川槐 沈利 LI Min;DENG Shouhao;LIU Chuanhuai;SHEN li(College of Energy and Mechanical Engineering,Shanghai University of Electric Power,Shanghai 201306,China;Fengtai Power Generation Branch of Huaizhe Coal Power Co.,LTD.,Huainan 232131,China)

机构地区：[1]上海电力大学能源与机械工程学院,上海201306 [2]淮浙煤电有限公司凤台发电分公司,安徽淮南232131

出　　处：《有色金属工程》2022年第9期9-15,共7页Nonferrous Metals Engineering

基　　金：国家自然科学基金资助项目(52005315)。

摘　　要：采用ERNiCr-3镍基焊丝作为T91/TP347H异种钢焊接接头的焊料,使用X射线衍射分析仪、光学显微镜、扫描电子显微镜和显微硬度计研究了原始态、服役6×10^(4)h和服役10^(5)h的T91/TP347H异种接头的相组成、微观组织、元素组成及显微硬度。结果表明,随着服役时间的增加,T91母材、TP347H母材和焊缝区晶粒尺寸均有一定程度的增大,T91母材存在析出相M_(23)C_(6),TP347H母材存在析出相M_(23)C_(6)、Nb(C,N),焊缝区有少量M_(23)C_(6)存在。在服役过程中发生Fe、Ni元素的扩散。三种状态下的焊接接头均在T91热影响区硬度最高,TP347H母材硬度最低,随着服役时间的增加,焊缝打底层硬度基本不变,而焊缝盖面层和填充层的硬度急剧升高,其余区域硬度均有下降。ERNiCr-3 nickel-based welding wire was used as the solder of T91/TP347H dissimilar steel welding joints,The phase composition,microstructure,elements,and microhardness of T91/TP347H dissimilar welding joints in original state,service for 6×10^(4)h and service for 105 h were characterized by X-ray diffraction analyzer,optical microscope,scanning electron microscope and microhardness tester.The results showed that with the increase of service time,the grain size of T91 base metal,TP347H base metal and weld zone increased to a certain extent.T91 base metal had precipitated phases M_(23)C_(6),and TP347H base metal had precipitated phases M_(23)C_(6) and Nb(C,N),there is a small amount of M_(23)C_(6) in the weld area.The diffusion of Fe and Ni elements occurred during service.The welded joints in the three states have the highest microhardness in the T91 heat-affected zone,and the microhardness of the TP347H base metal was the lowest.With the increase of service time,the microhardness of the weld bottom layer was basically unchanged,while the microhardness of the weld cover layer and filler layer rise sharply,the microhardness of other areas decreased.

关 键 词：T91钢 TP347H钢 异种钢焊接接头 微观组织 显微硬度 

分 类 号：TG142.1[一般工业技术—材料科学与工程]