12MnNiVR钢板大热输入焊接接头组织与性能  

Study on microstructure and properties of 12MnNiVR steel welded joint with high heat input

作　　者：范益 李伟 王锟艺 王晓斌 邹家生[2] 刘坤 严铿[2] FAN Yi;LI Wei;WANG Kunyi;WANG Xiaobin;ZOU Jiasheng;LIU Kun;YAN Keng(Jiangsu Key Laboratory for Premium Steel Materials,Nanjing Iron&Steel Co.,Ltd.,Nanjing 210035,China;School of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212100,China)

机构地区：[1]江苏省高端钢铁材料重点实验室,南京钢铁股份有限公司,南京210035 [2]江苏科技大学材料科学与工程学院,江苏镇江212100

出　　处：《压力容器》2023年第3期21-27,共7页Pressure Vessel Technology

基　　金：国家自然科学基金项目(52105351);江苏省自然科学基金项目(BK20210890);中国博士后科学基金面上项目(2022M722928);江苏省高等学校基础科学(自然科学)研究项目(21KJB460015)。

摘　　要：采用12MnNiVR钢建造的10万m 3及以上原油储罐的纵缝焊接多采用气电立焊,大热输入对接头组织和性能有重要影响。对采用大热输入气电立焊的12MnNiVR钢板进行焊接试验,分析了焊接接头的微观组织和力学性能,重点研究了焊接接头的冲击韧性。研究结果表明:在大热输入焊接下,焊缝组织为大量针状铁素体,粗晶区为侧板条铁素体,粗晶区和细晶区之间有明显的过渡区域,细晶区为细小铁素体与珠光体,不完全重结晶区为粗大块状铁素体和珠光体。热影响区显微硬度由熔合线侧到母材侧表现出先增大、后减小、再增大的规律,最小值为177HV10。拉伸和弯曲性能优良;焊接接头在-20℃下的冲击吸收能量均大于80 J;由于熔合线处的侧板条铁素体晶粒粗大,熔合线冲击吸收能量较低为84 J,断口形貌为准解理形貌特征。In the construction of crude oil storage tanks with a capacity of 100000 m 3 and above,12MnNiVR steel was welded by gas-electric vertical welding.High heat input has an important influence on the microstructure and properties of the joints.12MnNiVR steel plate was tested by gas-electric vertical welding with large heat input.The microstructure and mechanical properties of welded joints were analyzed,and the impact toughness of welded joints was studied.The results show that under high heat input welding,the weld microstructure is a large amount of acicular ferrite,the coarse grain zone is side lath ferrite,there is a clear transition zone between the coarse grain zone and the fine grain zone,the fine grain zone is fine block ferrite and pearlite,and the incomplete recrystallization zone is coarse block ferrite.The microhardness of the heat affected zone increases first,then decreases and then increases with the increase of the distance from the fusion line to the base metal,and the minimum value is 177HV10.The tensile and bending properties of the joints are excellent,the impact absorption energy of welded joints at-20℃is greater than 80 J.Due to the coarse ferrite grain of the side plate at the fusion line,the impact absorption energy of the fusion line is low,which is 84 J,and the fracture morphology is quasi-cleavage morphology.

关 键 词：12MnNiVR钢 大热输入 组织 热影响区 力学性能 

分 类 号：TH140.7[一般工业技术—材料科学与工程] TG446[机械工程—机械制造及自动化] TG406[金属学及工艺—焊接]