Synthesis and characterization of Al2O3/SiC composite ceramics via carbothermal reduction of aluminosilicate precursor for solar sensible thermal storage
Synthesis and characterization of Al2O3/SiC composite ceramics via carbothermal reduction of aluminosilicate precursor for solar sensible thermal storage
复制标题
DOI：
10.1016/j.jallcom.2015.12.038
复制
发表时间：
2016-03
影响因子：
6.2
通讯作者：
Xiaohong Xu;Xinbin Lao;Jianfeng Wu;Yaxiang Zhang;Xiaoyang Xu;Kun Li
中科院分区：
文献类型：
--
作者：
Xiaohong Xu;Xinbin Lao;Jianfeng Wu;Yaxiang Zhang;Xiaoyang Xu;Kun Li
采用碳热还原法去除硅铝酸盐前驱体中的二氧化硅，原位形成高热容、高导热率的Al2O3材料与SiC结合，合成Al2O3/SiC复合陶瓷。研究了 1460–1580 °C 温度范围内的相变、微观结构演变和相关性能变化。结果表明，Y2O3的添加显着提高了碳热反应速率，并将碳热反应结束温度降低至1500℃。原位形成的Al2O3的掺入可以降低SiC陶瓷的烧结温度而不降低热容量。在最佳温度1540℃下烧结，得到热容为1.16J/(g·K)、高导热系数为13.73W/(m·K)的Al2O3/SiC复合陶瓷。较高的导热系数使复合材料具有良好的抗热震性能。本研究旨在确定通过简单的原位合成方法获得具有良好形貌和性能的显热储热材料的反应条件。
Al2O3material with high heat capacity and high thermal conductivity was in situ formed to bond with SiC for synthesizing Al2O3/SiC composite ceramics by the removal of silica in aluminosilicate precursor using carbothermal reduction method. Phase transformation, microstructural evolution, and the relevant variations in properties were studied in the temperature range 1460–1580 °C. Results indicated that the addition of Y2O3improved the carbothermal reaction rate significantly and decreased the finish temperature of carbothermal reaction to 1500 °C. Incorporation of the in situ formed Al2O3could lower the sintering temperature of SiC ceramic without decreasing the heat capacity. By sintering at the optimal temperature as 1540 °C, Al2O3/SiC composite ceramics with the heat capacity of 1.16 J/(g·K) and the high thermal conductivity of 13.73 W/(m·K) were obtained. The relatively high thermal conductivity endowed the composites with a good thermal shock resistance. This study was intended to identify the reaction conditions for obtaining sensible thermal storage materials with favorable morphology and properties by using a simple in situ synthesis method.