熔盐堆结构材料的涂层技术研究  

Coating Technique on Structural Materials of Molten Salt Reactor

作　　者：刘艳红[1] 杨超[1] 王晓婧[1] 李怀林[1] 陆燕玲[2] 周兴泰[2] 

机构地区：[1]国家电投集团中央研究院,北京102209 [2]中国科学院上海应用物理研究所,上海201800

出　　处：《稀有金属》2016年第9期908-913,共6页Chinese Journal of Rare Metals

基　　金：中国科学院战略性先导科技专项项目(XDA02040000);国家核电技术公司员工自主创新项目(SNP-KJ-CX-2014-10)资助

摘　　要：熔盐堆中使用的结构材料除了要保证高温力学性还要在高温下与熔盐具有良好的相容性,本文拟采用涂层技术,在高温力学性能较好的镍基合金上沉积一层耐氟盐腐蚀的纯镍金属层,解决镍基合金与高温氟盐相容性差的问题。纯镍金属层采用脉冲电沉积的方法获得,系统研究了电流密度对涂层性能的影响,并通过扫描电镜(SEM)和X射线衍射(XRD)等测试手段对涂层微观形貌、结构特征等进行分析。结果表明,随着电流密度的增加,涂层厚度呈线性增加,电流密度为40 m A·cm-2时,涂层厚度达102μm;而涂层织构系数(TC)在不同电流密度下都呈现(111)晶面增大而(200)晶面减小的趋势,织构强弱变化的本质与镍晶体不同晶面的表面能大小、沉积过电位、Ni(OH)2和氢原子对生长晶面的吸附作用有关;涂层显微硬度随着电流密度增大呈现出增加趋势。The structural materials used in molten salt reactor should be chemically compatible with fluoride salts at high temperatures apart from having high temperature mechanical performances. The coating technique was applied in this research to obtain pure nickel coating on nickel alloy. Using a pure nickel coating as a corrosion-resistant layer on nickel-based alloy substrate could improve the cor- rosion resistance to fluoride salt. The influence of different current densities on coating properties was investigated ; the mierostrueture morphology was analyzed by scanning electron microscope （SEM） and X-ray diffraction （XRD）. The results showed that the thickness of nickel layer increased linearly with current densities. Moreover, the thickness reached 102 Ixm when the current density was 40 mA·cm-2. At the same time, the texture coefficient showed upward trend on （111） crystal plane but downward trend on （200） crystal plane. The essence of texture coefficient change was related to the surface energy of different crystal planes, the deposition over- voltage and the absorption of Ni （OH）2 and hydrogen atoms to growth crystal planes. Furthermore, the micro-hardness showed an in- creasing trend with the current density increasing.

关 键 词：熔盐堆 电流密度 镍基合金 微观结构 显微硬度 

分 类 号：TL34[核科学技术—核技术及应用]