镍基690合金在超纯水中常温下的电化学行为及高温高压下的腐蚀行为  

Electrochemical Behavior of Nickel-Based Alloy 690 in Room-Temperature Ultrapure Water and Its Corrosion Behavior in High-Temperature and High-Pressure Ultrapure Water

作　　者：张晖 李成涛 宋利君 史庆峰 王海卫 任爱 刘飞华 李岩 

机构地区：[1]中核核电运行管理有限公司二厂,浙江海盐314300 [2]苏州热工研究院电站寿命管理研究中心,江苏苏州215004

出　　处：《材料保护》2013年第10期37-39,6,共3页Materials Protection

基　　金：国家自然科学基金(钢铁联合研究基金)(U1260201)资助

摘　　要：目前,国内对镍基690合金在超纯水中的腐蚀行为报道不多。利用动电位极化和电化学阻抗法研究了镍基690合金在常温超纯水中的电化学行为;利用扫描电镜、能谱和X射线衍射等方法研究了镍基690合金在高温高压超纯水中的腐蚀行为。结果表明:镍基690合金在纯水中常温下具有较小的腐蚀电流密度和较大的阻抗,耐蚀性较好;镍基690合金在高温高压超纯水中浸泡4 400 h后,表面仅产生轻微腐蚀,腐蚀产物由双层钝化膜结构组成,外层富Ni内层富Cr,可有效抑制腐蚀反应的进一步发生,从而表现出优良的耐蚀性能。The electrochemical behavior of Ni-based 690 alloy in room-temperature ultrapure water was investigated with potentiodynamic polarization curve method and electrochemical impedance spectroscopic method. Furthermore,a scanning electron microscope,an energy dispersive spectrometer,and an X-ray diffractometer were performed to examine the corrosion behavior of the Ni-based alloy in high-temperature-high-pressure ultrapure water. Results indicated that,in room-temperature ultrapure water,Ni-based 690 alloy had a small corrosion current density and a high impedance,showing good corrosion resistance. Besides, after being immersed in high-temperature-high-pressure ultrapure water for 4 400 h,the Ni-based alloy experienced only slight surface corrosion,and its corroded products formed a dual-layer film consisting of Ni-rich outer layer and Cr-rich inner layer. As a result,the corrosion reaction of the Ni-based alloy was effectively inhibited,corresponding to good corrosion resistance.

关 键 词：镍基690合金 超纯水 常温电化学行为 高温高压腐蚀行为 

分 类 号：TG172[金属学及工艺—金属表面处理]