SiC基太阳能热发电吸热陶瓷制备及热性能分析(英文)  

Preparation and Thermal Properties of SiC Based Solar Heat Absorbing Ceramic

作　　者：吴建锋[1] 刘孟[1] 徐晓虹[1] 张亚祥[1] 劳新斌 李坤[1] 

机构地区：[1]武汉理工大学料科学与工程学院,武汉430070

出　　处：《硅酸盐学报》2012年第11期1685-1692,共8页Journal of The Chinese Ceramic Society

基　　金：国家"973"计划(2010CB227105)资助项目

摘　　要：吸热材料是塔式太阳能热发电中的核心部件,其热性能起着至关重要的作用。本工作研究了以红柱石、SiC、高岭土以及石英为原料,采用陶瓷制备工艺无压烧结制备SiC基吸热陶瓷。测试和分析了烧结样品的抗折强度、热膨胀系数、抗热震性、热导率、耐火度、氧化增重率、物相组成以及显微结构。结果表明:SiC基吸热陶瓷样品具有高耐火度和热导率、低热膨胀系数和氧化增重率以及良好的抗热震性和均匀的微观结构。经1460℃烧结后,最佳配方样品的抗折强度为32.52 MPa、热膨胀系数为6.32×10–6℃–1、30次热震无裂纹且强度增加率为11.15%、室温热导率为10.03W/(m.K)、耐火度为1 650℃、1 300℃氧化3 h后样品氧化增重率为2.769 mg/cm2。样品主晶相为α-SiC、莫来石和石英,存在较多连通气孔,孔径为10～20μm。如果将吸热器材料用SiC基吸热陶瓷替代,吸热器将会表现出更好的稳定性,可望用于塔式太阳能热发电高温吸热器用吸热材料。A heat-absorbing material of SiC based ceramic was prepared by a pressureless sintering method. Andalusite, SiC, Kaolin clay and quartz were used as the raw materials. The bending strength, thermal expansion coefficient, thermal shock resistance, thermal conductivity, refractoriness, growth rate of oxidation mass, phase composition and mierostrueture were analyzed.The results indicate that SiC based heat absorbing ceramic with the symmetrical microstructure has a higher refractoriness, a greater thermal conductivity, a lower thermal expansion coefficient, a lower growth rate of oxidation mass and a superior thermal shock resistance as well. The sample with optimized formulation with the bending strength of 32.52 MPa and the thermal expansion coefficient of 6.32 × 10^-6℃-1 was obtained at the sintering temperature of 1460 ℃. The phase composition is ct-SiC, mullite and cristobalite. It was observed that there are many connected pores with the sizes of 10-20 μm in the sample. When the absorber material is replaced by SiC based ce- ramic, the absorber exhibits a better stability, indicating its potential applications in intermediate and high temperature absorber in tower type solar thermal power generation.

关 键 词：太阳能热发电 吸热陶瓷 碳化硅基陶瓷 无压烧成 热性能 微观结构与性能 

分 类 号：TM285[一般工业技术—材料科学与工程]