5%Ni低温钢MAG多层多道焊接接头的微观组织与力学性能

doi:10.3901/JME.260501

摘要/Abstract

摘要： 5%Ni钢由于合金元素含量较高，导致焊接性较差，制约了其在低温压力容器领域的广泛应用。针对低温储罐用50 mm厚5%Ni低温钢，开展双面MAG多层多道焊接实验，采用光学显微镜、扫描电镜和拉伸试验机等手段对接头的微观组织和力学性能进行了表征和测试。结果表明：焊接接头成型良好；焊缝组织是奥氏体树枝晶；母材受到焊接热循环形成热影响区，热影响区主要由板条马氏体、回火索氏体和少量M-A组元组成，多次热循环导致碳化物的析出和碳元素的偏析，促进了M-A组元的形成。焊缝区平均硬度238 HV₁₀，接头峰值硬度306 HV₁₀出现在粗晶热影响区，亚临界热影响区硬度较母材有所降低，硬度为190 HV₁₀，这与回火软化有关；接头平均抗拉强度674 MPa，平均屈服强度510 MPa，平均伸长率24%，断裂位置和亚临界热影响区相对应；接头熔合线微区的冲击功最低，平均值为92 J，熔合线冲击功较熔合线+2 mm位置低33%，靠近熔合线的粗晶热影响区发生了明显脆化现象，粗晶热影响区粗大的板条马氏体和M-A组织以及链状碳化物会降低接头低温韧性。研究结果对于MAG焊接工艺在5%Ni钢低温压力容器焊接领域的推广应用具有积极意义。

关键词: 5% Ni钢, MAG焊, 多层多道焊, 热影响区, 低温韧性

Abstract: 5%Ni steel has poor weldability due to its high content of alloying elements, which restricts its wide application in the field of pressure vessels. The microstructure and mechanical properties of 50 mm thick 5%Ni low-temperature steel for low temperature storage tank were characterized and tested by optical microscopy, scanning electron microscopy and tensile testing machine. The results show that the welded joint is well formed. The weld structure is austenitic dendrite. The heat affected zone(HAZ) is formed by welding thermal cycling. The HAZ is mainly composed of lath martensite, tempered sorbite and a small amount of M-A components. Multiple thermal cycles lead to the precipitation of carbides and segregation of carbon elements, which promotes the formation of M-A components. The average hardness of the weld zone is 238 HV₁₀, the peak hardness of the joint is 306 HV₁₀ in the coarse-grained heat affected zone, and the hardness of the joint in the subcritical heat affected zone is lower than that of the base material, and the hardness is 190 HV₁₀, which is related to tempering and softening. The average tensile strength of the joint is 674 MPa, the average yield strength is 510 MPa, and the average elongation is 24%. The fracture location corresponds to the subcritical heat affected zone of the joint. The impact energy in the micro-zone of the fusion line is the lowest, with an average value of 92 J. The impact energy of the fusion line is 33% lower than that at the +2 mm position of the fusion line. Obvious embrittlement occurs in the coarse-grained HAZ near the fusion line. Coarse lath martensite and M-A and chain carbides in the heat affected zone of coarse grains reduce the low temperature toughness of welded joints. The results are of positive significance for the popularization and application of MAG welding process in the field of low-temperature pressure vessel welding of 5% Ni steel.

Key words: 5% Ni steel, MAG welding, multi-layer and multi-pass welding, heat affected zone, low temperature toughness

中图分类号:

TG406

曾志伟, 黄贺楠, 张露云, 鲍佳宇, 孙家禄, 张峻巍. 5%Ni低温钢MAG多层多道焊接接头的微观组织与力学性能[J]. 机械工程学报, 2026, 62(10): 219-230.

ZENG Zhiwei, HUANG Henan, ZHANG Luyun, BAO Jiayu, SUN Jialu, ZHANG Junwei. Microstructure and Mechanical Properties of 5%Ni Low-temperature Steel MAG Multi-layer Welded Joint[J]. Journal of Mechanical Engineering, 2026, 62(10): 219-230.

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链接本文: http://www.cjmenet.com.cn/CN/10.3901/JME.260501

http://www.cjmenet.com.cn/CN/Y2026/V62/I10/219

参考文献

[1] 颜丙锁，马红广，汪春标，等. LNG储罐中9Ni低温钢焊接[J]. 焊管，2013，36(2)：29-31. YAN Bingsuo，MA Hongguang，WANG Chunbiao，et al. The 9Ni low temperature steel welding of LNG store tank[J]. Welded Pipe and Tube，2013，36(2)：29-31.
[2] 康凌风，蔡艳，张跃龙，等. 交流方波参数对9Ni钢埋弧焊接头组织和性能的影响[J]. 热加工工艺，2017，46(13)：84-89. KANG Lingfeng，CAI Yan，ZHANG Yuelong，et al. Effects of AC square waveform parameter on microstructure and properties of 9Ni steel submerged arc welding joint[J]. Hot Working Technology，2017，46(13)：84-89.
[3] ZHAO Lin，TIAN Zhiling，PENG Yun. Porosity and nitrogen content of weld metal in laser welding of high nitrogen austenitic stainless steel[J]. ISIJ International，2007，47(12)：1772-1775.
[4] BONNEFOIS B，COUDREUSE L，CHARLES J. A-TIG welding of high nitrogen alloyed stainless steels：A metallurgically high-performance welding process[J]. Welding International，2004，18(3)：208-212.
[5] 强伟，王克鸿，侯瑶. 保护气体中氮气比例对高氮钢双面同轴TIG焊接工艺性的影响[J]. 焊接学报，2017，38(9)：70-74，132. QIANG Wei，WANG Kehong，HOU Yao. Effect of N₂ ratio in shielding gas on welding process characteristic in double-sided coaxial TIG welding of high nitrogen steel[J]. Transactions of the China Welding Institution，2017，38(9)：70-74，132.
[6] 周勇，张成文，张国军，等. MAG焊接技术研究进展[J]. 热加工工艺，2023，52(15)：6-12. ZHOU Yong，ZHANG Chengwen，ZHANG Guojun，et al. Research progress of MAG welding technology[J]. Hot Working Technology，2023，52(15)：6-12.
[7] 王艳杰，赵琳，彭云，等. 中锰汽车钢焊接热影响区组织与韧性[J]. 机械工程学报，2022，58(24)：84-93. WANG Yanjie，ZHAO Lin，PENG Yun，et al. Microstructure and toughness of welding heat affected zone of medium manganese automobile steel[J]. Journal of Mechanical Engineering，2022，58(24)：84-93.
[8] 王博士，陈楠楠，蔡艳，等. 低合金贝氏体高强钢模拟焊接粗晶热影响区低温疲劳韧脆转变行为及机制[J]. 机械工程学报，2024，60(6)：271-278. WANG Boshi，CHEN Nannan，CAI Yan，et al. Low-temperature fatigue ductile-to-brittle transition behavior and mechanism for simulated coarse-grained heat-affected zone of a high-strength low-alloy bainite steel[J]. Journal of Mechanical Engineering，2024，60(6)：271-278.
[9] 曹志民，张贵锋，张建明，等. Q690C粒状贝氏体钢MAG焊接头中M-A组元的演变及其对热影响区冲击韧度的影响[J]. 机械工程学报，2014，50(20)：84-92. CAO Zhimin，ZHANG Guifeng，ZHANG Jianming，et al. Evolution of M-A constituents in HAZ and its effect on toughness of MAG joint of granular bainitic steel Q690C[J]. Journal of Mechanical Engineering，2014，50(20)：84-92.
[10] 肖晓明，彭云，娄宇航，等. EH40船板钢大热输入埋弧焊接头韧化机理研究[J]. 机械工程学报，2013，49(8)：97-104. XIAO Xiaoming，PENG Yun，LOU Yuhang，et al. Study on the toughening mechanism of joint of EH40 ship plate steel with high heat input submerged arc welding[J]. Journal of Mechanical Engineering，2013，49(8)：97-104.
[11] XIN Dongqun，CAI Yan，HUA Xueming. Effect of preheating on microstructure and low-temperature toughness for coarse-grained heat-affected zone of 5% Ni steel joint made by laser welding[J]. Welding in the World，2019，63(5)：1229-1241.
[12] BARRICK E J，DUPONT J N. Mechanical properties and microstructural characterization of simulated heat-affected zones in 10 wt pct Ni steel[J]. Materials Science and Engineering：A，2019，748：189-204.
[13] CAO Rui，YANG Zhaoqing，LI Jinmei，et al. Effect of peak temperature on microstructure and mechanical properties of thermally simulated welding heat-affected zones for 09MnNiDR steel[J]. Journal of Materials Engineering and Performance，2020，29(11)：7063-7072.
[14] WANG M，SUN M. Effects of cooling rate on microstructure and phase transformation temperature of 5Ni steel[J]. Journal of Northeastern University (Natural Science)，2014，35(2)：223.
[15] 李员妹. 节Ni低温钢组织性能及亚稳奥氏体稳定性影响因素的研究[D]. 昆明：昆明理工大学，2015. LI Yuanmei. Study on tissue properties and austenite stability of Ni low-temperature steel[D]. Kunming：Kunming University of Science and Technology，2015.
[16] 尹燕，李雪，朱旻，等. 9Ni钢焊条电弧焊接头组织与性能[J]. 电焊机，2015，45(12)：138-141. YIN Yan，LI Xue，ZHU Min，et al. Analysis on microstructure and properties of welded joint for 9Ni steel with SMAW welding[J]. Electric Welding Machine，2015，45(12)：138-141.
[17] ZHANG Zhongke，CHU Shusheng，XIONG Jianqiang，et al. The effect of solid solution temperature on the precipitation phase and properties of plasma arc welded joints of Inconel625 high temperature alloy[J]. Materials Research Express，2022，9(12)：126508.
[18] ZHANG L N，OJO O A. Corrosion behavior of wire arc additive manufactured Inconel 718 superalloy[J]. Journal of Alloys and Compounds，2020，829：154455.
[19] RIOS M，FILHO J P，FARIAS F，et al. Microstructural characterization of the simulated heat-affected zone of 9 pct Ni steel[J]. Metallurgical and Materials Transactions A，2021，52：5016-5031.
[20] 于磊，王红鸿，汪兴隆. 铝对大线能量焊接条件下HSLA焊接热影响区粗晶区M-A组元及冲击韧性的影响[J]. 电焊机，2014，44(11)：69-72. YU Lei，WANG Honghong，WANG Xinglong. Influence of M-a constituents and the impact toughness of simulated heat-affected zone in HSLA steels by addition of aluminum with high heat input[J]. Electric Welding Machine，2014，44(11)：69-72.
[21] CUI Bing，LIU Zhengwei，LIU Zheng，et al. Effect of welding heat input on microstructural evolution and impact toughness of the simulated coarse-grained heat-affected zone of Q960 steel[J]. Welding in the World，2023，67(1)：235-249.
[22] BAI Wei，XU Xiaojun，LIU Yaolan，et al. Microstructural evolutions and impact toughness in simulated welding heat affected zones for a high-strength carbide-free bainitic rail steel[J]. Materials Science and Engineering：A，2023，880：145325.
[23] JANG J I，LEE B W，JU J B，et al. Experimental analysis of the practical LBZ effects on the brittle fracture performance of cryogenic steel HAZs with respect to crack arrest toughness near fusion line[J]. Engineering Fracture Mechanics，2003，70(10)：1245-1257.
[24] KIM B C，LEE S，KIM N J，et al. Microstructure and local brittle zone phenomena in high-strength low-alloy steel welds[J]. Metallurgical Transactions A，1991，22(1)：139-149.
[25] 严春妍，李午申，薛振奎，等. 焊接工艺参数对9%Ni钢热影响区低温韧性的影响[J]. 焊接学报，2008，29(10)：101-104，118. YAN Chunyan，LI Wushen，XUE Zhenkui，et al. Effects of welding parameters on cryogenic toughness in heat-affected zones for 9% Ni steel[J]. Transactions of the China Welding Institution，2008，29(10)：101-104，118.
[26] MAIA P P N，MINÁ É M，DALPIAZ G，et al. Microstructural characterisation and micromechanical investigation of the heat-affected zone in multi-pass welding of 9Ni steel pipes[J]. Journal of Materials Research and Technology，2023，24：1716-1732.
[27] MU Weidong，CAI Yan，WANG Min，et al. Microstructure characteristics and properties of fusion boundary in 9%Ni steel joint filled with Ni-based alloy[J]. Materials Characterization，2020，165：110390.
[28] DAN W J，LI S H，ZHANG W G，et al. The effect of strain-induced martensitic transformation on mechanical properties of TRIP steel[J]. Materials & Design，2008，29(3)：604-612.
[29] 王超，党文静，鲁路，等. 回火次数对P91焊管接头力学性能的影响[J]. 工程科学学报，2017，39(4)：529-534. WANG Chao，DANG Wenjing，LU Lu，et al. Influence of tempering times on the mechanical properties of P91 weld joints[J]. Chinese Journal of Engineering，2017，39(4)：529-534.
[30] 严春妍，李午申，薛振奎，等. LNG储罐用9%Ni钢及其焊接性[J]. 焊接学报，2008，29(3)：49-52. YAN Chunyan，LI Wushen，XUE Zhenkui，et al. Review of 9% Ni steel and its weldability[J]. Transactions of the China Welding Institution，2008，29(3)：49-52.
[31] 朱波，王文科，郭洋，等. 12Cr/30Cr2Ni4MoV异种转子钢焊接接头微区冲击韧性研究[J]. 机械工程学报，2021，57(2)：53-61. ZHU Bo，WANG Wenke，GUO Yang，et al. Research on impact toughness in microzones of 12Cr/30Cr2Ni4MoV dissimilar rotor steel welded joint[J]. Journal of Mechanical Engineering，2021，57(2)：53-61.
[32] LAMBERT-PERLADE A，GOURGUES A F，PINEAU A. Austenite to bainite phase transformation in the heat-affected zone of a high strength low alloy steel[J]. Acta Materialia，2004，52(8)：2337-2348.
[33] MCMAHON C J，COHEN M. Initiation of cleavage in polycrystalline iron[J]. Acta Metallurgica，1965，13(6)：591-604.
[34] 兰亮云，邱春林，赵德文，等. 低碳贝氏体钢焊接热影响区中不同亚区的组织特征与韧性[J]. 金属学报，2011，47(8)：1046-1054. LAN Liangyun，QIU Chunlin，ZHAO Dewen，et al. Microstructural characters and toughness of different sub-regions in the welding heat affected zone of low carbon bainitic steel[J]. Acta Metallurgica Sinica，2011，47(8)：1046-1054.
[35] 张丽红，陈芙蓉，常建刚. 焊接热循环对09MnNiDR钢热影响区低温韧性的影响[J]. 焊接学报，2020，41(3)：91-96，101-102. ZHANG Lihong，CHEN Furong，CHANG Jiangang. Effect of weld thermal cycle on low temperature toughness of 09MnNiDR steel heat affected zone[J]. Transactions of the China Welding Institution，2020，41(3)：91-96，101-102.