Effect of intermediate tempering on microstructure and mechanical properties of heat affected zone of 15Cr1Mo1V steel after repair welding

doi:10.13251/j.issn.0254-6051.2024.05.023

Abstract

Abstract: Heat affected zone of 15Cr1Mo1V steel after repair welding and intermediate tempering was simulated by Gleeble-3500 thermal simulation testing machine. The effect of intermediate tempering on the microstructure and mechanical properties of the heat affected zone of the long-term serviced 15Cr1Mo1V steel after repair welding was studied by means of metallographic observation, scanning electron microscopy analysis, microhardness test and impact test. The results show that the microstructure of serviced state is composed of ferrite+ granular bainite+intragranular dispersed carbide+grain boundary chain carbide. After repair welding, the microstructure of tempering zone is basically the same as that of long-term serviced state. The microstructure of incomplete transformation zone and complete transformation zone is ferrite+granular bainite+pearlite+granular grain boundary carbide, but there is dispersed carbide in the crystal of incomplete transformation zone. The coarse grain zone is composed of flat noodles bainite+a small amount of granular bainite. After intermediate tempering, there is an increase in carbides at the grain boundaries of the tempering zone. The carbides precipitated in the incomplete and complete phase transformation zones continuously aggregate and grow at the grain boundaries, while a large number of chain like carbides appear at the grain boundaries of the coarse grain zone. After repair welding, except for the high hardness of the coarse grain zone, the hardness level of the other heat affected zones is not significantly different from the serviced state. After intermediate tempering, the hardness value of the coarse grain zone remains at the level after repair welding, and the hardness of the other heat affected zones has slightly increased. Due to the presence of pearlite structure in the incomplete and complete phase transformation zones, the impact property is lower, while the impact property of the tempered zone and coarse grain zone is better. After intermediate tempering, the impact property of the tempered zone and coarse grain zone decreases, while the impact property of other heat affected zones is improved.

Key words: intermediate tempering, 15Cr1Mo1V steel, welding heat affected zone, microstructure, properties

CLC Number:

TG156.5

Zhang Zhenghua, Li Xiao, Wang Yansong, Xiao Shijun. Effect of intermediate tempering on microstructure and mechanical properties of heat affected zone of 15Cr1Mo1V steel after repair welding[J]. Heat Treatment of Metals, 2024, 49(5): 140-145.

References

[1]Shi W, Lü Y S, Chen Z B, et al. Cause analysis and preventive measures against cracks in 15Cr1Mo1V steel welded joint in service[J]. Applied Mechanics and Materials, 2017, 863: 328-333.
[2]Xia X, Zhang G, Xue F, et al. Material identification and safety evaluation of defective 15Cr1Mo1V steel[C]//Advances in Materials Processing: Proceedings of Chinese Materials Conference 2017 18th. Springer, Singapore, 2018.
[3]Hong Y Y, Feng W J, Nan L J, et al. Ageing embrittlement of 15Cr1Mo1V steel welded joints evaluated by small punch test[J]. Advanced Materials Research, 2010, 160: 1223-1227.
[4]陈忠兵, 张立君, 梁军, 等. 在役15X1M1Φ钢焊接接头早期失效分析及其预防[J]. 金属热处理, 2012, 37(11): 119-124.
Chen Zhongbing, Zhang Lijun, Liang Jun, et al. Analysis and countermeasures for earlier failure of welded joint of 15X1M1Φ steel in service[J]. Heat Treatment of Metals, 2012, 37(11): 119-124.
[5]Xia X, Zhu B, Zhang G, et al. Tracking supervision of service performance and life assessment of defective 15Cr1Mo1V steel pipeline[J]. International Journal of Pressure Vessels and Piping, 2019, 178: 103891.
[6]赵彦芬, 张路, 张欣原, 等. 高温主汽用15X1M1Φ钢接头失效及解决措施[J]. 中国电力, 2010, 43(8): 1-6.
Zhao Yanfen, Zhang Lu, Zhang Xinyuan, et al. Failure analysis and solution of 15X1M1Φ welded joints for main steam pipelines operated on high temperature[J]. Electric Power, 2010, 43(8): 1-6.
[7]Varjonen H. Dissimilar Metal Weld Inspection, Monitoring and Repair Approaches[M]. Vienna: International Atomic Energy Agency, 2018.
[8]王昊, 宋利, 袁宝子, 等. 某电厂三通焊接接头开裂原因分析[J]. 理化检验(物理分册), 2019, 55(7): 501-505.
Wang Hao, Song Li, Yuan Baozi, et al. Cause analysis on cracking of welded joint of tee in a power plant[J]. Physical Testing and Chemical Analysis (Part A: Physical Testing), 2019, 55(7): 501-505.
[9]叶栋林. 实用电弧焊技术[M]. 哈尔滨: 黑龙江科学技术出版社, 1985.
[10]关婧, 蔡庆伍, 武会宾, 等. 回火温度对轧后直接水淬15CrMoV钢组织和力学性能的影响[J]. 特殊钢, 2009, 30(2): 66-67.
Guan Jing, Cai Qingwu, Wu Huibin, et al. Effect of tempering temperature on structure and mechanical properties of steel 15CrMoV direct-water-quenched after finishing rolling[J]. Special Steel, 2009, 30(2): 66-67.
[11]徐琛, 陈广兴, 张勇伟, 等. 1.25Cr-0.5Mo钢热处理后的组织与力学性能[J]. 金属热处理, 2021, 46(6): 200-204.
Xu Chen, Chen Guangxing, Zhang Yongwei, et al. Microstructure and mechanical properties of 1.25Cr-0.5Mo steel after heat treatment[J]. Heat Treatment of Metals, 2021, 46(6): 200-204.
[12]何彪, 赵庆权, 肖功业, 等. 15Cr1Mo1V高压锅炉管的开发及其高温组织稳定性研究[J]. 钢管, 2019, 48(2): 21-24.
He Biao, Zhao Qingquan, Xiao Gongye, et al. Development of 15Cr1Mo1V high-pressure boiler pipe and study on stability of its high-temperature structure[J]. Steel Pipe, 2019, 48(2): 21-24.
[13]刘树云. 12Cr1MoV钢管热处理工艺与组织性能的关系[J]. 钢铁研究, 1995, 23(1): 25-29, 35.
Liu Shuyun. Dependence of structure property of 12Cr1MoV steel pipe on hot treatment process[J]. Research on Iron and Steel, 1995, 23(1): 25-29, 35.
[14]张玉慧, 王士林, 张少平. 珠光体耐热钢15Χ1М1Φ的焊接新工艺[J]. 吉林电力, 2003, 31(3): 49-51.
Zhang Yuhui, Wang Shilin, Zhang Shaoping. Welding of 115Χ1М1Φ pearlitic heat rexisting steel[J]. Jilin Electric Power, 2003, 31(3): 49-51.
[15]徐永明, 胡永祥, 朱祥. 15Cr1Mo1V阀体与WB36配管焊接方法[J]. 阀门, 2017(1): 25-26.
Xu Yongming, Hu Yongxiang, Zhu Xiang. The welding method of dissimilar steel welding between 15Cr1Mo1V body and WB36 piping[J]. Valve Magazine, 2017(1): 25-26.
[16]王兆平. 15Cr1Mo1V钢焊接工艺研究与实践[J]. 东北电力技术, 2006, 27(5): 4-7.
Wang Zhaoping. Research and practice on 15CrlMolV steal welding technique[J]. Northeast Electric Power Technology, 2006, 27(5): 4-7.
[17]胡克迈. Gleeble 3500数控热机模拟试验系统[J]. 物理测试, 2006, 24(5): 34-36.
Hu Kemai. Digital controlled Gleeble 3500 thermal-mechanical testing system[J]. Physics Examination and Testing, 2006, 24(5): 34-36.
[18]胡光立, 康沫狂, 陆禹, 等. 15CrMoV钢奥氏体连续冷却转变图的测定及应用[J]. 金属热处理, 1984(8): 15-21.
Hu Guangli, Kang Mokuang, Lu Yu, et al. The determination and application of the CCT diagram of 15CrMoV steel[J]. Heat Treatment of Metals, 1984(8): 15-21.
[19]句光宇, 吕煜, 刘文生, 等. 运行1.2×10⁵ h 15Cr1Mo1V钢主蒸汽管及R317焊缝的组织和性能[J]. 金属热处理, 2019, 44(6): 29-32.
Ju Guangyu, Lü Yi, Liu Wensheng, et al. Microstructure and properties of 15Cr1Mo1V steel main steam pipe and R317 welded joint after 1.2×10⁵ h service[J]. Heat Treatment of Metals, 2019, 44(6): 29-32.
[20]胥永刚, 李宁, 蔡光军, 等. 铬、铌和钒对9Cr-1Mo钢焊缝回火组织性能的影响[J]. 焊接学报, 2002, 23(5): 49-52.
Xu Yonggang, Li Ning, Cai Guangjun, et al. Effect of chromium, niobium and vanadium contents on 9Cr-1Mo tempered weld metal microstructure and tensile properties[J]. Transactions of The China Welding Institution, 2002, 23(5): 49-52.
[21]刘永超, 陆皓. 焊后热处理对T23钢热影响粗晶区微观组织的影响[J]. 热加工工艺, 2013, 42(11): 36-38, 42.
Liu Yonghao, Lu Hao. Effect of PWHT on microstructure of coarse-grained heat-affected zone of T23 steel[J]. Hot Working Technology, 2013, 42(11): 36-38, 42.
[22]Auzoux Q, Allais L, Caes C, et al. Effect of pre-strain on creep of three AISI 316 austenitic stainless steels in relation to reheat cracking of weld-affected zones[J]. Journal of Nuclear Materials, 2010, 400(2): 127-137.
[23]杨希锐, 邹建新, 宋利, 等. 长期时效下15Cr1Mo1V钢的显微组织及力学性能[J]. 金属热处理, 2019, 44(4): 190-194.
Yang Xirui, Zou Jianxin, Song Li, et al. Microstructure and mechanical properties of 15Cr1Mo1V steel during long-term aging[J]. Heat Treatment of Metals, 2019, 44(4): 190-194.
[24]匡成阳, 马煜林, 王辰昱, 等. 回火温度对耐热钢组织和性能的影响[J]. 金属热处理, 2022, 47(7): 129-133.
Kuang Chengyang, Ma Yulin, Wang Chenyu, et al. Effect of tempering temperature on microstructure and properties of heat-resistant steel[J]. Heat Treatment of Metals, 2022, 47(7): 129-133.
[25]周浩, 王云, 曾燕屏. 高温回火P91钢显微组织演变及再结晶机理[J]. 金属热处理, 2023, 48(11): 38-44.
Zhou Hao, Wang Yun, Zeng Yanping. Effect of high-temperature tempering on microstructure evolution and recrystallization mechanism of P91 steel[J]. Heat Treatment of Metals, 2023, (11): 38-44.