氧化膜在太阳能热发电储能氯化物熔盐中失效机制研究

项目名称： 氧化膜在太阳能热发电储能氯化物熔盐中失效机制研究

项目编号： No.51201131

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 金属材料学科

项目作者： 朱明

作者单位： 西安科技大学

项目金额： 25万元

中文摘要： 与硝酸盐熔盐相比，氯化物熔盐是一种能够在更高温度工作的太阳能热发电蓄热介质，但其对合金材料的腐蚀速率较高，需要在合金材料表面制备合适的涂层以降低腐蚀速率，提高系统的稳定性。本研究拟采用热扩散渗后预氧化的方法在镍基高温合金及不锈钢表面制备Al2O3、Cr2O3、SiO2等常见保护性氧化膜，采用TG/DSC、SEM/EDS、TEM等分析测试方法研究常见保护性氧化膜在熔融氯化物盐中的稳定性，分析氧化膜在氯化物熔盐中的失效机制，明确氯化物熔盐中阴离子和阳离子在氧化膜破坏过程中的作用机制以及环境氧分压对氧化膜破坏过程的影响,为氯化物熔盐腐蚀防护涂层体系选择提供理论依据，建立一种通过改变环境气氛降低氯化物熔盐腐蚀速率的方法，为氯化物熔盐在太阳能热发电领域的大规模应用奠定基础。

中文关键词： 太阳能热发电；氯化物熔盐；高温腐蚀；熔盐电化学；稀土元素

英文摘要： Compared to molten nitride salts, molten chloride salts can serve at higher temperature acting as thermal storage materials in solar thermal power generation field. However, the corrosion rate is very severe. In order to improve the stability of the solar thermal power system, protective coatings must be fabricated on the surfaces of the metals/alloys to reduce the corrosion rate of them. In the present work, Al2O3, Cr2O3 and SiO2 protective oxide scales will be obtained on the surface of the packing cemented Ni-based superalloy and stainless steel by pre-oxidation.TG/DSC, SEM/EDS, TEM are used to study the stability of these protective oxide scals and to determine the failure mechanism of these protective oxide scales in the molten chloride salts,especially the role of anions and cations in the molten chrolide salts and the effects of oxygen partial pressure on the failure process of the protective oxide scales. The aim of this study is to theoretically surpport the selection of protective coating system for the molten chloride salts corrosion and to bulid a method to reduce the corrosion rate of the molten chloride salts by changing the oxygen partial pressure. These can lay the foundation for the wide using of the molten chloride salts in the solar thermal power generation field.

英文关键词： Solar thermal power generation；Molten Chloride salt；high temperature corrosion；Molten salt electrochemistry；Rare earth element