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Acta Metall Sin  2015, Vol. 51 Issue (8): 925-934    DOI: 10.11900/0412.1961.2014.00719
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EFFECTS OF TEMPERING TEMPERATURE ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF GRANULAR BAINITE IN 2.25Cr-1Mo-0.25V STEEL
Zhonghua JIANG,Pei WANG(),Dianzhong LI,Yiyi LI
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016
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Zhonghua JIANG,Pei WANG,Dianzhong LI,Yiyi LI. EFFECTS OF TEMPERING TEMPERATURE ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF GRANULAR BAINITE IN 2.25Cr-1Mo-0.25V STEEL. Acta Metall Sin, 2015, 51(8): 925-934.

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Abstract  

2.25Cr-1Mo-0.25V steel is the most popular material used for pressure-vessel applied at elevated-temperature in hydrogen environment. For higher process efficiencies in future coal-conversion plants, chemical processing plants, and petrochemical-refining plants, much thicker cross-section component are necessary for constructing much larger pressure-vessel for these plants. Because of the thick cross-section, the cooling rate in the central region of the component is insufficient to obtain low bainite during quenching treatment, and a large amount of granular bainite appears in the central region. Previous studies have shown that good impact toughness can be achieved by appropriate tempering for 2.25Cr-1Mo-0.25V steel with low bainite microstructure. However, the impact toughness of 2.25Cr-1Mo-0.25V steel with granular bainite after tempering always cannot satisfy the demanding requirement due to the unclear understanding of the evolution of microstructure and mechanical properties during tempering. In this work, the influence of tempering on the microstructure and mechanical properties of 2.25Cr-1Mo-0.25V steel with granular bainite microstructure was investigated by OM, XRD, SEM, TEM and EPMA. The results show that the normalized 2.25Cr-1Mo-0.25V steel with granular bainite microstructure is composed of bainite ferrite and island of martensite and austenite (M-A island). Nanoindentation test indicates that M-A island is much harder than that of metrix bainite ferrite, because of the high concentration of carbon in M-A islands. The synergistic effect of the decomposition of M-A islands and softening of bainite ferrite determined that Charpy absorbed energy at -18 ℃ increases first and then decreases with the increasement of tempering temperature. The degree of decomposition of M-A islands and the morphology, size and distribution of carbides in granular bainite, coupled with the softening effect of bainite ferrite recrystallization are the key factors determining low-temperature impact toughness of 2.25Cr-1Mo-0.25V steel.
Key words:  2.25Cr-1Mo-0.25V steel      granular bainite      impact toughness      M-A island     
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Zhonghua JIANG
Pei WANG
Dianzhong LI
Yiyi LI

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https://www.ams.org.cn/EN/10.11900/0412.1961.2014.00719     OR     https://www.ams.org.cn/EN/Y2015/V51/I8/925

Material C Cr Mo V Ni Mn Si P S Fe
Standard ≤0.17 2.0~2.5 0.9~1.1 0.25~0.35 ≤0.25 0.3~0.6 ≤0.10 ≤0.015 ≤0.010 Bal.
Experimental 0.14 2.46 1.00 0.28 0.15 0.59 0.05 0.006 0.002 Bal.
Table 1  Chemical compositions of the steel 2.25Cr-1Mo-0.25V in ASME standard and this work
Fig.1  OM (a) and SEM (b) images of nomalized 2.25Cr-1Mo-0.25V steel (M-A—martensite-austenite)
Fig.2  Representative load-displacement curves recorded during nanoindentations of bainite ferrite and M-A island
Fig.3  Distribution of carbon element in granular banite obtained by EPMA
Fig.4  Bright field (a) and dark field (b) TEM images of martensite in the M-A island
Fig.5  Effects of tempering temperature on the mechanical properties of 2.25Cr-1Mo-0.25V steel
Fig.6  Effects of tempering temperature on the impact toughness of 2.25Cr-1Mo-0.25V steel
Fig.7  SEM images of normalized 2.25Cr-1Mo-0.25V steel tempered at 500 ℃ (a), 630 ℃ (b), 680 ℃ (c), 700 ℃ (d), 720 ℃ (e) and 750 ℃ (f)
Fig.8  TEM images of 2.25Cr-1Mo-0.25V steel normalized (a) and tempered at 630 ℃ (b), 680 ℃ (c), 700 ℃ (d), 720 ℃ (e) and 750 ℃ (f) (Insets show the corresponding SAED patterns)
Fig.9  Fracture surface morphologies of 2.25Cr-1Mo-0.25V steel tempered at 500 ℃ (a), 630 ℃ (b), 680 ℃ (c), 700 ℃ (d), 720 ℃ (e) and 750 ℃ (f) after Charpy impact test at -18 ℃ (Arrows in Fig.9b indicate ductile fracture bands and inset in Fig.9d indicates a region of dimples)
Fig.10  CLSM images of the cross-sectional area of the Charpy impact specimens fractured at -18 ℃ for the 2.25Cr-1Mo-0.25V steel normalized and tempered at 500 ℃ (a), 630 ℃ (b), 680 ℃ (c), 700 ℃ (d), 720 ℃ (e) and 750 ℃ (f) (Arrows indicate the corresponding microcracks)
[1] Bhadeshia H K D H. Bainite in Steels. 2nd Ed., London: The Institute of Materials, 2001: 323
[2] Klueh R L, Swindeman R W. Metall Trans, 1986; 17A: 1027
[3] Tao P, Zhang C, Yang Z G. Acta Metall Sin, 2009; 45: 51 (陶 鹏, 张 弛, 杨志刚. 金属学报, 2009; 45: 51)
[4] Guo J. Master Thesis, Yanshan University, Qinhuangdao, 2004 (郭 建. 燕山大学硕士学位论文, 秦皇岛, 2004)
[5] Li Z J, Xiao N M, Li D Z, Zhang J Y, Luo Y J, Zhang R X. Acta Metall Sin, 2014; 50: 777 (李振江, 肖纳敏, 李殿中, 张俊勇, 罗永建, 张瑞雪. 金属学报, 2014; 50: 777)
[6] Gojic M, Kosec L, Matkovic P. J Mater Sci, 1988; 33: 395
[7] Yu J, Mcmahon C J. Metal Trans, 1980; 11A: 277
[8] Qu Y B, Huang X Q, Cao B, Cai Z P, Pan J L. Chin J Mech Eng, 2011; 47(14): 44 (屈岳波, 黄欣泉, 曹 彬, 蔡志鹏, 潘际銮. 机械工程学报, 2011; 47(14): 44)
[9] Klueh R L, Nasreldin A M. Metall Trans, 1987; 18A: 1279
[10] Luo Y, Peng J M, Wang H B, Wu X C. Mater Sci Eng, 2010; A527: 3433
[11] Zhang Y T, Song G B, Zhang H Q, Li J F. 139th Annual Meeting & Exhibition—Supplemental Proceedings, Vol.3, Seattle, USA, 2010 (CD-ROM)
[12] Kovacs B V. AFS Trans, 1994; 102: 417
[13] Lambert A, Drillet J, Gourgues A F, Sturel T, Pineau A.?Sci Technol Weld Join, 2000; 5: 168
[14] Fang H S, Bai B Z, Zheng X H, Zheng Y K, Chen X Y, Zhao R F. Acta Metall Sin, 1986; 22: 238 (方鸿生, 白秉哲, 郑秀华, 郑燕康, 陈秀云, 赵如发. 金属学报, 1986; 22: 238)
[15] Sun S W, Mao J F, Lei T Q, He L L. Acta Metall Sin, 2000; 36: 1009 (孙树文, 茅建富, 雷廷全, 贺连龙. 金属学报, 2000; 36: 1009)
[16] Sun S W, Lei T Q, Tang Z X, Chen J L, You G, Wang X. Iron Steel, 1997; 32(12): 41 (孙树文, 雷廷全, 唐之秀, 陈家伦, 犹 公, 王 欣. 钢铁, 1997; 32(12): 41)
[17] Lei T C, Sun J, Tang C H, Lei M. Mater Sci Technol, 1990; 6(2): 124
[18] Irani J J, May M J, Elliott D. ASTM STP 407, Philadelphia: ASTM,1968: 168
[19] Tezuka H,Sakurai T. Int J Pressure Vessel Pipe, 2005; 82: 165
[20] Guan K, Xu X, Xu H, Wang Z. Nucl Eng Des, 2005; 235: 2485
[21] Briant C L. Mater Sci Technol, 1989; 5: 138
[22] Michaud P, Delagnes D, Lamesle P, Mathon M H. Acta Mater, 2007; 25: 4877
[23] Yang H, Kim S. Mater Sci Eng, 2001; A319: 316
[24] Lan L Y, Qiu C L, Zhao D W, Gao X H, Du L X. Mater Sci Eng, 2011; A529: 192
[25] Chen J H, Kikuta Y, Araki T, Yoneda M, Matsuda Y. Acta Metall, 1984; 32: 1779
[26] Davis C L, King J E. Metall Mater Trans, 1994; 25A: 563
[27] Hu G L, Liu Z T, Wang P, Hwa W J, Kang M K. Mater Sci Eng, 1991; A141: 221
[28] Chen J D, Mo W L, Wang P, Lu S P. Acta Metall Sin, 2012; 48: 1186 (陈俊丹, 莫文林, 王 培, 陆善平. 金属学报, 2012; 48: 1186)
[29] Gao G H, Zhang H, Bai B Z. Acta Metall Sin, 2011; 47: 513 (高古辉, 张 寒, 白秉哲. 金属学报, 2011; 47: 513)
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