| Solar energy has a rich, inexhaustible, and will not pollute the environment and damage the ecological balance and so on. Solar thermal power generation is one of the most economic ways which is the most likely to cause an energy revolution, to achieve high power generation, alternative to conventional energy sources. However, solar energy has intermittent and instability characteristics, so the heat storage material must be used to improve the utilization of solar energy to reduce the cost. The heat storage material has low heat storage density and thermal storage efficiency and so on, a single phase change materials will occur in the use of solid-liquid inter-conversion, must be packaged by a special container, which will not only increase the transfer thermal medium and the thermal resistance between the phase change material, improve heat transfer efficiency and reduce heat loss, but also can prone to cold, phase separation, aging, and container corrosion problems, particularly the high temperature phase change materials, heat loss and the container corrosion problems is extremely seriously, and increasing the use cost of the solid-liquid phase change materials.Based on the defeat of single sensible heat or latent heat storage materials, solar latent-heat storage composite ceramics were prepared in this paper, the effect of structure, properties by the different formulations and firing temperature of Al2O3-ZrO2 (AZ series) and Al2O3-SiC-ZrO2 (ASZ series) two series of composite ceramic material, the performance of phase change material, the formulations, molding methods, firing system and the combination of mechanism of packing agent were studied, the phase change material in the honeycomb ceramic in different fill ways and quantities were designed and the latent-heat storage density of materials were calculated.Using theα-Al2O3, partially stabilized zirconia(PSZ)(Y2O3 5.2%), andalusite, kaolin, cordierite, talc as the main raw material, AZ series formula composition were designed, dry milling, semi-dry press molding, and the composite ceramic materials of AZ series were prepared by pressureless sintering method. The performance and microstructure of the samples were tested by XRD, SEM and other means. The results show that the mechanical strength of the samples were significantly improved by the addition of micro-level partially stabilized zirconia, the thermal shock resistance of the samples were significantly improved by the addition of cordierite, the mechanical strength of the samples were improved by adding 20wt% than 10wt% of the micro-level zirconia, the thermal shock resistance of the samples were improved by adding 20wt% than 10wt% of cordierite. When the addition of micron zirconia and cordierite is 10wt%, the thermal storage ceramic matrix material of AZ series (B4 formula) were prepared by fired at 1340℃for 2h, the porosity was 31.48%, the water absorption was 12.59%, the bulk density was 2.50g·cm-3, the bending strength was 60.83MPa, the sample wasn't cracked by thermal shock resistance (room temperature-800℃, air-cooled) after 30 times, and flexural strength after thermal shock was 68.83 MPa (the growth rate of strength was 13.15%), the thermal expansion coefficient of the sample was 5.26×10-6℃-1, and the heat capacity was 0.28kJ·(kg·K)-1, the thermal conductivity coefficient was 0.01cm2·s-1, the thermal conductivity was 0.45 W·m·K)-1, the heat storage density was 240.42kJ·kg-1 at 600℃. XRD analysis showed that the main phase of the corundum samples were tetragonal zirconia, andalusite, mullite, cordierite. SEM results showed that the sample was dense of B4 formula before and after thermal shock, a small vent hole and the size were a few tenths ofμm-50μm, the grains were growth and development good, the grain size was 10μm-80μm, and were packaged by a small amount of glass phase and connected closely, spherical alumina zirconia crystal and the crystal was closely connected by the way of intergranular type, which can get the high intensity and thermal shock resistance of the samples. Which can be used as the heat storage matrix material of solar thermal power generation.Using theα-Al2O3, PSZ(Y2O35.2%), silicon carbide, andalusite, cordierite, talc as the main raw material, ASZ series formula composition were designed, dry milling, semi-dry press molding, and the composite ceramic materials of ASZ series were prepared by pressureless sintering method. The performance and microstructure of the samples were tested by XRD, SEM and other means. The results showed that with the increase of SiC content, the mechanical strength was increased gradually, the thermal shock resistance of the samples was improved; when the addition of SiC was 50wt%, the thermal storage ceramic matrix material of ASZ series (C5 formula) were prepared by fired at 1280℃for 2h, the porosity was 24.88%, water absorption was 10.44%, bulk density was 2.38g·cm-3, the bending strength was 66.20MPa, the sample wasn't cracked by thermal shock resistance (room temperature-800℃, air-cooled) after 30 times, and flexural strength after thermal shock was 76.99MPa (the growth rate of strength was 27.89%), the thermal expansion coefficient of the sample was 5.85×10-6℃-1, and the heat capacity was 1.05kJ·(kg·K)-1, the thermal conductivity coefficient was 0.01cm2·s-1, the thermal conductivity was 2.26W·(m·K)-1, the heat storage density was 916.91 kJ·kg-1 at 600℃. XRD analysis showed that the main phase of the corundum samples were tetragonal zirconia, andalusite, mullite, cordierite. SEM results showed that the sample was dense of B4 formula before and after thermal shock, a small vent hole and the size were a few tenths ofμm～50μm, the grains were growth and development good, the grain size was 10μm～80μm, and were packaged by a small amount of glass phase and connected closely, spherical alumina zirconia crystal and the crystal was closely connected by the way of intergranular type, which can get the high intensity and thermal shock resistance of the samples. Which was met the requirements of heat storage matrix material of solar thermal power generation.Using C5 formula as the main raw material, adding different amounts of high-temperature adhesives, designed formula composition of package agent, the samples were prepared by use of plastic molding and two-stage firing technology. The combination of the matrix material and the package agent were studied by using thermal shock test and SEM microstructure of the samples. The results showed that: the binding property of the package agent and matrix material is good when the high temperature binder was 30wt% of the package agent, the other 5 groups of formula samples were cracked or Stratified with varying degrees. The thermal storage density was calculated when filled in the honeycomb ceramics in different locations and filled different content of the phase change material, the results showed that with the increase of the amount of phase change materials packaged, the heat storage density of latent heat-heat ceramic composites were increased; with the increase of the temperature, the heat storage density were also increased. When the phase change material were filled with 2/3 of ceramic honeycomb holes and filled with 2/3 volume of each hole, the temperature was 600℃, the heat storage density was 1132.16kJ·kg-1 of the best formula C5, when the temperature was 1000℃, the heat storage density was 1590.80 kJ·kg-1 of the best formula C5. The results showed that the heat storage density of latent-sensible heat thermal energy storage composite ceramics which the PCM was packaged in the ASZ ceramic was significantly higher than that of a single sensible heat or latent heat storage, which is an excellent of solar high-temperature thermal storage material.
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