750℃高温CO_(2)掺杂SO_(2)环境中Super304H及Inconel625的腐蚀行为  

High Temperature Corrosion of Super304H and Inconel625 in Carbon Dioxide Doping With Sulfur Dioxide Environment at 750℃

作　　者：周永莉 赵钦新[1] 鲁金涛[2] 袁勇[2] 梁志远[1] 杨珍[2] 黄锦阳[2] ZHOU Yongli;ZHAO Qinxin;LU Jintao;YUAN Yong;LIANG Zhiyuan;YANG Zhen;HUANG Jinyang(Key Laboratory of Thermal Fluid Science and Engineering of MOE(School of Energy and Power Engineering,Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China;National Engineering Research Center of Clean Coal Combustion for Utility Boilers(Xi’an Thermal Power Research Institute Co.,Ltd.),Xi’an 710032,Shaanxi Province,China)

机构地区：[1]热流科学与工程教育部重点实验室(西安交通大学能源与动力工程学院),陕西省西安市710049 [2]电站锅炉煤清洁燃烧国家工程中心(西安热工研究院有限公司),陕西省西安市710032

出　　处：《中国电机工程学报》2024年第11期4387-4394,I0017,共9页Proceedings of the CSEE

基　　金：华能科技项目(HNKJ24-H02,HNKJ23-H53);国家自然科学基金(面上项目)(52271070)。

摘　　要：研究掺杂气体对合金的腐蚀行为及作用机理对超临界二氧化碳(supercritical carbon dioxide,S-CO_(2))发电技术具有重要意义。该文开展Super304H及Inconel625合金的高温CO_(2)腐蚀试验,并结合腐蚀增重法、扫描电镜观察及XRD分析,研究两种耐热合金在750℃CO_(2)及掺杂SO_(2)环境中的腐蚀行为。结果表明,两种合金在750℃CO_(2)、750℃CO_(2)+SO_(2)环境中的腐蚀动力学均遵循抛物线规律,Inconel625抗腐蚀能力优于Super304H,具有较少的腐蚀增重;Super304H在750℃CO_(2)腐蚀初期增重高于CO_(2)+SO_(2)环境,而120 h后在CO_(2)+SO_(2)环境中腐蚀增重较高。两种环境中腐蚀500 h后,Super304H表面氧化膜为单层Cr_(2)O_(3)及外层疏松瘤状富铁氧化物与内氧化物FeCr_(2)O_(4)组成的局部双层氧化膜;Inconel625为单层均匀致密Cr_(2)O_(3)氧化膜,平均厚度不到1μm。高温CO_(2)腐蚀环境中,Cr含量对提高合金抗腐蚀性能具有至关重要的作用。高温CO_(2)掺杂SO_(2)对于Cr_(2)O_(3)形成合金具有抑制渗碳的作用,对于氧化铁形成合金具有加速腐蚀及渗碳作用。It is of great significance for supercritical carbon dioxide(S-CO_(2))power generation technology to study the corrosion behavior and mechanism of alloys in the environment of CO_(2)containing doping gas.High temperature corrosion experiment of Super304H and Inconel625 alloy in CO_(2),together with corrosion weighting method,scanning electron microscope and X-ray diffraction(XRD)are applied to study the corrosion behavior of the two heat resistant materials in CO_(2)doping with SO_(2)environment at 750℃.The results show that the oxidation kinetic of the materials follows the parabolic law under 750℃CO_(2)and 750℃CO_(2)+SO_(2)environment.Inconel625 has a better corrosion resistant ability than Super304H,accompanied by less oxidation weight gain.The initial weight gain of Super304H in 750℃CO_(2)is higher than that in CO_(2)+SO_(2),while the weight gain gets larger in CO_(2)+SO_(2)after 120 h.The single Cr_(2)O_(3)oxide scales and the double-layered oxide scales consist of nodular-typed Fe3O4 outer layer and FeCr_(2)O_(4)inner layer formed on Super304H after exposure 500 h in two environments.Whereas a stable and dense Cr-rich oxide layer of about 1μm in thickness grows on Inconel625.The Cr content plays a crucial role to improve the alloy corrosion resistance in high temperature CO_(2)environment.High temperature CO_(2)doping with SO_(2)has the effect of inhibiting carburization during the formation of Cr_(2)O_(3),accelerating corrosion and carburization for iron oxide.

关 键 词：耐热合金 高温CO_(2) 掺杂气体 SO_(2) 腐蚀 渗碳 

分 类 号：TG178[金属学及工艺—金属表面处理]