Property and Microstructure Evolution of 20G Steel under High Temperature Loading
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摘要: 对水冷壁管用20G钢在室温至850 ℃进行了拉伸试验，还在550~850 ℃同步进行了蠕变（应力为62 MPa）及时效（不施加应力）试验，研究了温度对拉伸性能，以及蠕变和时效后的组织和性能演变的影响。结果表明：蠕变及时效后试验钢的显微组织均由铁素体和珠光体组成，应力的施加促进了珠光体的球化；随温度的升高，试验钢的抗拉强度先略有减小后增大随后再快速下降，屈服强度呈近似线性下降趋势，伸长率先降低后增大再波动性下降；随温度的升高，试验钢的蠕变断裂时间先急剧降低后趋于稳定，在550 ℃下蠕变断裂受晶界蠕变孔洞形核控制，在650 ℃下则由塑性损伤控制。Abstract: Tensile testing from room temperature to 850℃ and synchronous creep testing (stress of 62 MPa) and aging treatment (no stress) at 550-850℃ were conducted on 20G steel for water wall tube. The effects of temperature on tensile properties and involution of structure and properties after creep and aging were studied. The results show that the microstructures of tested steel after creep and aging were all composed of ferrite and pearlite. The applied stress improved the spheroidization of pearlite. With imcreasing temperature, the tensile strength of tested steel decreased slightly and then increased and then decreased rapidly; the yield strength decreased approximately linearly; the elongation decreased and then increased and then decreased in fluctuations. With the rise of temperature, the creep fracture time of tested steel was shortened rapidly and then became stable. The creep fracture was controlled by creep cavity nucleation at grain boundaries at 550℃ while by plasticity damage at 650℃.
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Keywords:
- 20G steel /
- mechanical property /
- creep behavior /
- pearlite spheroidization
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[1] 杨勇平, 杨志平, 徐钢,等. 中国火力发电能耗状况及展望[J]. 中国电机工程学报, 2013, 33(23):1-11. [2] 牟超. 滦河发电厂运行车间作业流程优化研究[D]. 长春:吉林大学, 2015. [3] 张维平. 蒸汽锅炉炉管爆裂原因分析[J]. 机械工程材料, 2006,30(9):76-78. [4] 洪峰. 浅谈对锅炉防"四管"泄漏管理经验[J]. 中国电力教育, 2011(18):127-129. [5] 王立坤, 周杨, 荣军,等. 某电厂水冷壁管爆裂原因分析[J]. 理化检验-物理分册, 2016, 52(11):828-832. [6] 邱建平. 水冷壁管爆管案例综合分析[J]. 电力安全技术, 2007, 20(8):38-41. [7] 陈二松. 200MW超高压电站锅炉水冷壁爆管泄露原因分析[C]//中国计量协会冶金分会2013年会论文集.北京:冶金自动化杂志社,2013:271-273. [8] 王大伟. 超临界锅炉爆管事故的分析和处理[J]. 广东电力, 2007, 20(7):65-67. [9] 马晓艺, 刘高飞, 陈文强. 火电厂水冷壁管失效分析[J]. 热加工工艺, 2014(20):223-226. [10] 徐洪. 高压锅炉水冷壁管失效分析[J]. 中国腐蚀与防护学报, 2003, 23(5):312-315. [11] 张锦云. 锅炉水冷壁管失效金相分析[J]. 钢铁研究, 1994(2):32-34. [12] 曹海兵, 刘世刚. 关于某锅炉水冷壁管爆管的失效分析[J]. 装备制造技术, 2016(8):208-210. [13] 闫水保, 郑立军, 张营帅. 电厂锅炉水冷壁管短时过热爆管的故障树分析[J]. 广东电力, 2008, 21(2):44-47. [14] 徐庆立. 蒸汽锅炉水冷壁管变形事故的原因分析[J].天津建材,2010(4):45-46. [15] 潘家祯. 压力容器材料实用手册[M]. 北京:化学工业出版社, 2000. [16] SUZUKI M, OOKUBO N, HIRAMATSU A. Effect of cementite morphology on mechanical properties of medium- and high-carbon steels[J]. Nisshin Steel Technical Report(Japan), 2001, 81:1-9.
[17] 朱晓东, 李承基, 章守华,等. 奥氏体化状态和钒对珠光体型钢轨钢韧性的影响[J]. 北京科技大学学报, 1996(6):532-537. [18] 王运炎, 朱莉. 塑性变形加速钢中碳化物球化过程的机理探讨[J]. 成都大学学报(自然科学版), 1994(1):16-20. [19] TAO W U, WANG M, GAO Y, et al. Effects of plastic warm deformation on cementite spheroidization of a eutectoid steel[J]. Journal of Iron and Steel Research, International, 2012, 19(8):60-66.
[20] 戴涛. Q235钢等温球化工艺可行性研究[J]. 航天制造技术, 1993(5):9-12. [21] 潘学军, 刘一男. 废热锅炉蒸发管弯制过程中开裂原因分析[J]. 产业与科技论坛, 2011, 10(5):34-35. [22] 李晓红, 辛希贤, 樊玉光. 高强度管线钢屈强比参数的一些探讨[J]. 石油机械, 2006, 34(9):105-107. [23] 王跃华, 李然, 宋进英,等. 奥氏体化时间对I&Q&P工艺处理低碳硅锰钢组织和拉伸性能的影响[J]. 机械工程材料, 2016, 40(11):54-57. [24] 汤鹏杰, 姜勇, 巩建鸣,等. 某热电厂20G钢锅炉水冷壁管鼓包的原因[J]. 机械工程材料, 2016, 40(1):101-105. [25] DOBRZA AN'G SKI J. Internal damage processes in low alloy chromium-molybdenum steels during high-temperature creep service[J]. Journal of Materials Processing Technology, 2004, 157/158:297-303.
[26] DOBRZA AN'G SKI J, ZIELI AN'G SKI A, SROKA M. Microstructure, properties investigations and methodology of the state evaluation of T23(2.25Cr-0.3Mo-1.6W-V-Nb) steel in boilers application[J]. Journal of Achievements in Materials and Manufacturing Engineering, 2009, 32(2):142-153.
[27] PARKER J D, PARSONS A W J. High temperature deformation and fracture processes in 214Cr1Mo-12Cr12Mo14V weldments[J]. International Journal of Pressure Vessels and Piping, 1995, 63(1):45-54.
[28] PARKER J D. Creep behaviour of low alloy steel weldments[J]. International Journal of Pressure Vessels and Piping, 1995, 63(1):55-62.
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