Incoloy800H合金晶间腐蚀敏化条件试验  

Experimental research on intergranular corrosion sensitization conditions for Incoloy800H alloy

作　　者：张贵泉[1] 刘永兵[1] 文慧峰[1] 彭伟超 孙雅萍[2] 龙国军[1] 姚建涛[1] ZHANG Guiquan;LIU Yongbing;WEN Huifeng;PENG Weichao;SUN Yaping;LONG Guojun;YAO Jiantao(Xi'an Thermal Power Research Institute Co.,Ltd.,Xi'an 710054,China;Huaneng Shandong Shidao Bay Nuclear Power Co.,Ltd.,Rongcheng 264312,China)

机构地区：[1]西安热工研究院有限公司,陕西西安710054 [2]华能山东石岛湾核电有限公司,山东荣成264312

出　　处：《热力发电》2018年第11期71-76,共6页Thermal Power Generation

基　　金：中国华能集团公司总部科技项目(HNKJ17-H23)~~

摘　　要：采用硫酸-硫酸铜腐刻试验和双环动电位电化学再活化(DL-EPR)试验研究Incoloy800H合金晶间腐蚀敏感性,分析敏化温度与敏化时间对Incoloy800H合金晶间腐蚀敏感性的影响。分别采用光学显微镜、扫描电子显微镜和X射线能谱对Incoloy800H合金敏化试样的微观结构和DL-EPR测试后的表面形貌、表面元素进行表征。结果表明:随着敏化温度升高和敏化时间延长,Incoloy800H合金的晶间腐蚀敏感性先增大后减小,在750℃敏化处理4 h后Incoloy800H合金的敏化程度最大,再活化率达到71.8%;高温环境下,碳化物在Incoloy800H合金晶界析出形成贫铬区,导致Incoloy800H合金出现晶间腐蚀倾向;当敏化温度和敏化时间超过临界值时,贫铬区发生铬元素的自修复,晶间腐蚀敏感性显著减小。Through the copper-copper sulfate method and double-loop electrochemical potentiokinetic reactivation technique(DL-EPR),the intergranular corrosion susceptibility of Incoloy800 alloy was tested.The effects of sensitive temperature and sensitive time on intergranular corrosion susceptibility of Incoloy800H alloy were investigated.The microstructure of the sensitized specimens,morphology and elements of the alloy after DL-EPR test were examined by optical microscope,scanning electron microscopy and X-ray energy dispersive spectroscopy,respectively.The results show that,the susceptibility of the Incoloy800H alloy increased at first and then decreased when the sensitive temperature rose and the sensitive time prolonged,and the highest susceptibility was observed after sensitization at 750℃for 4 h,the reactivation rate Ra reached 71.8%.At high temperatures,the carbide precipitated in grain boundary of the Incoloy800H alloy and a chromium-depleted zone formed,resulting in intergranular corrosion tendency of the Incoloy800H alloy.When the sensitive temperature and sensitive time exceeded a critical value,self-repair of chromium elements occurred in chromium-poor regions and the intergranular corrosion susceptibility reduced significantly.

关 键 词：Incoloy800H合金 腐蚀敏感性 晶间腐蚀 贫铬区 自修复 敏化时间 敏化温度 

分 类 号：TM621.8[电气工程—电力系统及自动化]