由于全球能源短缺和环境污染，以太阳能为代表的可再生能源技术正在迅速发展。太阳能储量大，分布广，但通常具有不连续性，限制了其应用。工业余热通常被排放到大气中，不仅浪费了能源，而且造成了环境问题。储能技术可以缓解能源供需失衡，实现能源的高效利用。相变材料（Phase Change Material，PCM）具有较高的蓄热密度，是重要的储能介质之一。随着第三代聚光太阳能电站（Concentrating Solar Power ,CSP）系统的发展，已开发的熔盐类相变储热材料已不能满足其对高温以及高储热密度的需求。因此，中高温储热材料的开发具有重要的意义。本论文的研究目的是开发中高温定型复合相变储热材料，对储热材料的配方和制备工艺进行了研究，主要工作和结论如下：（1）针对熔盐复合相变储热材料成本高的问题，开发了冶金渣（钢渣、矿渣）基定型复合熔盐储热材料。通过实验确定了钢渣和熔盐最佳配比（wt.%）为5∶5。之后通过扫描电子显微镜（Scanning Electron Microscope ，SEM），热重-差示扫描量热法（Thermogravimetric-Differential Scanning Calorimeter ，TG-DSC），闪射法导热仪（Laser flash analysis，LFA），X射线衍射（X-ray diffraction ，XRD）以及高低温冷热循环测试表征并分析了复合材料的微观结构、热性能、化学相容性以及循环稳定性。结果表明，太阳盐/钢渣（5∶5）复合储热材料定型效果良好，微观结构紧密；储热密度为528 kJ/kg（100 ~ 500 °C），热导率为2.21 W/(m·K)；冶金渣与太阳盐之间化学相容性良好；200次冷热循环后，复合材料保持良好结构和热性能。最后，对复合材料的制备成本进行了初步分析。通过对比得出，太阳盐/冶金渣复合材料比传统太阳盐复合材料成本降低了50%以上。太阳盐/冶金渣复合相变储热材料不仅可以大规模地应用于热能储存，而且为钢铁工业的废弃物回收利用提供了良好的选择。（2）为了满足工作温区和储热密度不断提高的要求，开发了玻璃体系定型高温复合相变储热材料。复合材料以软化温度范围宽，熔化热高且腐蚀性小的玻璃G-400为相变储热材料，多孔氧化铝为基体材料。随后对复合材料微观结构和热物理性能进行了表征。结果表明，制得的G-400/Al2O3复合储热材料定型效果良好，微观结构紧密。复合材料可操作温度达1300 °C，储热密度为1207 kJ/kg（400 ~ 900 °C），热导率2.70 W/(m·K)。复合材料具有良好的热化学相容性，700次冷热循环后复合材料保持良好储热性能。（3）对定型复合相变储热材料的制备工艺进行改进，采用两段式烧结方法，使得复合材料中熔盐的比重提高了10%，从而提高了太阳盐复合材料的潜热。并且复合材料无破裂无泄漏，定型效果优于一步烧结法。;Renewable energy technology represented by solar energy is developing rapidly due to the global energy shortage and environmental pollution. Solar energy is abundant and widely distributed, but usually discontinuous in energy supply, which limits its application. Industrial waste heat is often discharged into the atmosphere, which is not only a waste of energy, but also causes environmental problems. Energy storage technology can reduce imbalance between energy supply and demand，and realize the efficient utilization of energy. Thermal energy storage (TES) with phase change material (PCM) is promising due to the high heat storage density. With the development of the third generation Concentrated Solar Power (CSP) plants, the currently developed molten salt heat storage materials can no longer meet the requirements of high operating temperature and thermal storage density. It is of great significance to develop heat storage materials particularly in medium to high temperature range.The objective of this thesis is to develop form-stable composite PCM for medium and high temperature thermal energy storage. Various material formulations were studied, and the material fabrication process were examined. The main work and conclusions are as follows:(1) To mitigate the high cost of molten salt composite TES material, a form-stable metallurgical slag-based composite molten salt PCM was first developed in this thesis. The optimum mass ratio of steel slag and molten salt (Solar salt) is obtained as 5:5. The microstructure, thermal property, chemical compatibility and thermal stability of the composite PCM were subsequently characterized by Scanning Electron Microscope (SEM), Thermogravimetric-Differential Scanning Calorimeter (TG-DSC), Laser flash analysis (LFA), X-ray diffraction (XRD) and Hot-Cold cycler respectively. Results showed that there is no leakage as the composite material keeps good shape and compact microstructure. The thermal energy storage density of solar salt/steel slag (5:5) is 528 kJ/kg (100 ~ 500 °C) and the thermal conductivity is 2.21 W/(m·K). The composite material shows good chemical compatibility between solar salt and metallurgical slag and it maintains good structure and heat storage performance after 200 cycles. Finally, the capital cost of the composite PCM is preliminary analyzed and formulized. By comparison, it is concluded that solar salt/metallurgical slag composites have a cost reduction of more than 50% compared with traditional solar salt composites.The developed solar salt/metallurgical slag composite PCM is not only promising for large-scale application of thermal energy storage, but also gives an excellent option for waste recycling in steel industrial.(2) A form-stable G-400/Al2O3 composite PCM was synthesized successfully to meet the demand of good thermal performance in high temperature applications. In composites, glass G-400 with large softening temperature range, high heat of fusion and low corrosion is creatively selected and used as thermal storage PCM, and porous alumina is selected as the matrix material. The microstructure and thermal physical performance were characterized subsequently for the synthesized composite material. Results showed that the microstructure is compact. The operating temperature reaches up to 1300 °C, the heat storage density is 1207 kJ/kg (400 ~ 900 °C), and the thermal conductivity is 2.70 W/(m·K). The composite material shows good thermal and chemical compatibility. After undergoing 700 times thermal cycles, the composite material still maintains good thermal performance. (3) A two-stage sintering method was implemented into the fabrication process. The weight percentage of molten salt in composite PCM was increased by 10% and the latent heat of solar salt composites increased by 17%. Morphology characterization also showed that the composite material obtained by two-stage sintering method is better than that of one-step sintering method.