燃煤电站锅炉管材料HR3C在超临界水中的氧化机理研究  

Oxidation Mechanism of Boiler Tube Material HR3C in Supercritical Water of Coal-fired Power Plant

作　　者：孙建 刘跃东 刘同干 陈辉 方亚雄 杨文正 朱忠亮[3] SUN Jian;LIU Yuedong;LIU Tonggan;CHEN Hui;FANG Yaxiong;YANG Wenzheng;ZHU Zhongliang(State Energy Group Taizhou Power Generation Co.,Ltd.,Jiangsu Taizhou 225300,China;National Energy Group Science and Technology Research Institute Co.,Ltd.,Nanjing 210046,China;Key Laboratory of Power Station Energy Transfer,Conversion and System,Ministry of Education,North China Electric Power University,Beijing 102206,China)

机构地区：[1]国家能源集团泰州发电有限公司,江苏泰州225300 [2]国家能源集团科学技术研究院有限公司,南京210046 [3]华北电力大学电站能量传递转化与系统教育部重点实验室,北京102206

出　　处：《表面技术》2025年第8期116-125,共10页Surface Technology

基　　金：国家重点研发计划项目(2022YFB4100403)。

摘　　要：目的 获得奥氏体不锈钢HR3C在605℃-26 MPa和640℃-26 MPa超临界水环境中的抗氧化性能,为燃煤电站锅炉管材料损伤机理研究提供数据支撑。方法 在超临界水氧化实验平台开展了奥氏体钢HR3C在605℃-26 MPa和640℃-26 MPa超临界水中氧化2 000 h实验。为探究氧化膜生长机理,进一步开展了奥氏体钢HR3C在含H_(2)^(18)O超临界水中的氧化实验。利用电子天平、场发射电子显微镜、能谱仪、X射线衍射仪、X射线光电子能谱仪以及二次离子质谱仪对试样氧化动力学、氧化膜微观形貌、元素组成、物相成分以及^(18)O分布进行了检测。结果 奥氏体钢HR3C氧化动力学在605℃下遵循抛物线规律,640℃下偏离抛物线规律。HR3C表面形成的氧化膜主要为Fe_(3)O_(4)/尖晶石、Fe_(2)O_(3)、Cr_(2)O_(3)以及MnO。外层主要为富铁氧化物,内层为富铬氧化物。^(18)O主要分布于氧化膜外层。640℃下氧化2 000 h后氧化膜发生明显剥落。结论 温度的升高增加了HR3C的氧化速率和剥落倾向,氧化初期金属离子的扩散导致氧化膜生长,长时氧化过程金属离子和氧离子扩散导致双层氧化膜的形成。较高的富铬氧化物含量,是HR3C具有较高抗氧化性能的主要原因。High main steam parameters can effectively improve the generation efficiency of coal-fired power stations.However,once the temperature and pressure of water vapor exceed the critical point,it shows strong oxidation.Austenitic steel HR3C is widely used in superheaters and reheaters of power stations.It is very important to evaluate the high temperature oxidation property of HR3C in supercritical water.Oxidation experiments of austenitic stainless steel HR3C in supercritical water environments at 605,640℃and 26 MPa are performed to investigate the oxidation resistance of HR3C steel.The supercritical water oxidation experimental system can withstand the maximum temperature and pressure of 700℃and 27 MPa.The samples are suspended in the constant temperature section of the reactor.The experiment adopts the method of interrupt experiment at interrupt time points of 300,500,800,1500 and 2000 h respectively.The sample is weighed before and after the experiment.It provides a data support for the research on the damage mechanism of boiler tube material in coal-fired power stations.In order to explore the mechanism of oxide film growth,the oxidation experiment of austenitic steel HR3C in supercritical water containing H_(2)^(18)O is further carried out in a static autoclave.For the oxygen isotope labeling experiment,it is carried out in supercritical water(H_(2)^(16)O)for 100 h in a static reactor,followed by oxygen-containing isotope supercritical water(H_(2)^(16)O+H_(2)^(18)O).Based on the distribution of oxygen isotopes,it can reveal the diffusion path of oxygen and the growth process of the oxide film.The oxidation kinetics,surface oxide morphology and structure,elemental composition and phase composition are identified by electronic balance,scanning electron microscope(SEM)equipped with energy dispersive X-ray spectrometer,X-ray diffraction,X-ray photoelectron spectrometer and secondary ion mass spectrometer.The oxidation kinetics of austenitic steel HR3C follows near the parabolic law at 605℃and deviates from th

关 键 词：超临界水 氧化机理 二次离子质谱 氧化膜开裂 扩散过程 

分 类 号：TG172[金属学及工艺—金属表面处理]