难混溶合金高温相变储热胶囊的无容器凝固制备及性能研究

项目名称： 难混溶合金高温相变储热胶囊的无容器凝固制备及性能研究

项目编号： No.51274182

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 矿业工程

项目作者： 李建强

作者单位： 中国科学院过程工程研究所

项目金额： 80万元

中文摘要： 工业高温余热回收技术和大规模太阳能热发电技术面临能量供应非稳态、间歇性、供需不匹配的问题，迫切需要研究和开发高效储热技术，尤其是800oC以上的高温相变储热技术。金属基相变储热材料具有热导率高、储热密度大、工作温度高等优点，但高温液态金属的难封装问题始终制约着该类相变材料的发展和工业应用。本项目提出利用气动悬浮无容器凝固技术，通过调控难混溶合金液-液相分离过程，获得核-壳结构相变储热胶囊的创新思想，以实现Cu基高温相变材料的自封装。通过合理设计Cr-Cu和Fe-Cu合金和添加元素，系统研究凝固参数对核-壳结构的影响规律，深入分析液-液相分离过程中Stokes沉积、液相表/界面张力以及Marangoni对流等因素的协同作用，制备出囊壁为富Cr相或不锈钢、囊芯为富Cu相的完整相变胶囊，测试并优化胶囊热性能，揭示组织结构变化和失效机理，为实现金属相变材料的规模化制备与工业应用提供指导。

中文关键词： 金属相变储热材料；核壳结构；铜铬镍合金；电沉积；气动悬浮

英文摘要： High-temperature thermal energy storage (over 800oC ) is an nowaday essential issue for developing the technologies to recover the vastly industrial wast heat and to use the solar thermal energy, which needs to overome the problems associated with the mismatch between energy supply and demand. Metallic phase change mateials (MPCMs) have attracted considerable attention since they possess many merits, such as high storage density, constant endothermic-exothermal temperature, superior thermal conductivity, and so on. However, MPCMs over 800oC are suffering from the difficulty to seek an applicable approach for containing the active melts. In this project, we propose that self-capsuled immiscible alloys with core-shell structure could be an alternative MPCMs, which are formed from the spacial liquid-liquid seperation during solidification. Containerless solidification process using an aerodynamic levitator Cu-base is adopted which is beneficial to the precise control of main solidification parameter (composition, undercooling, cooling rate,etc.), elimination of container' influence, as well as the capability of in-situ observation of the levitated sample during solification.In our previous experiments, the Cu-base capsules obtained by this process have a metallic shell (Cr-base or Fe-base) with higher melting tempe

英文关键词： metallic phase change materials；core-shell structure；copper-chromium–nickel；electroplating；aerodynamic levitation