摘要
以混合碳酸盐为相变材料,以氧化镁为陶瓷基骨架材料,以鳞片石墨为导热增强剂,通过混合烧结法制备出中高温复合蓄热材料。基于XRD和SEM表征分析可知,添加鳞片石墨后复合材料具有较好的化学稳定性,而且由于鳞片石墨的原因复合材料形成较多的孔隙结构。通过分析添加鳞片石墨后复合材料的热物性可知,随着鳞片石墨含量的增加,复合材料的熔点基本不变,而其热导率不断提高。鳞片石墨含量为25%的混合碳酸盐/氧化镁复合材料在250℃和560℃时的热导率分别达到3.88 W/(m·K)和2.52 W/(m·K)。基于微观结构和界面层理论对复合材料的导热增强机制进行了分析与讨论。
The medium-and high-temperature composite heat storage materials were fabricated by the mixed sintering method using mixed carbonates as phase change materials,magnesium oxide as ceramic matrix material,and graphite flakes as heat transfer enhancer.Based on the characterizations of XRD and SEM,the resultant composite materials have shown enhanced chemical stability,as well as more pore structures due to the presence of graphite flakes.By analyzing the thermal properties of the composite materials with different contents of graphite flakes,it can be found that the melting points of the composite materials remain unchanged and their thermal conductivities increase continuously with the increase of the content of graphite flakes.When the content of graphite flakes is up to 25%,the thermal conductivity of the composite material reaches 3.88 W/(m?K)and 2.52 W/(m?K)at 250℃and 560℃,respectively.The enhancement mechanism of thermal conductivity of the composite materials is further discussed from the view of the microstructure and interface layer theories.
作者
桑丽霞
许永旺
李锋
张雅婷
马文童
陈旭
王浩
SANG Lixia;XU Yongwang;LI Feng;ZHANG Yating;MA Wentong;CHEN Xu;WANG Hao(Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Ministry of Education,Key Laboratory of Heat Transfer and Energy Conservation Beijing Municipality,Department of Energy Science and Engineering,College of Environmental and Energy Engineering,Beijing University of Technology,Beijing 100124,China)
出处
《储能科学与技术》
CAS
CSCD
2019年第5期886-890,共5页
Energy Storage Science and Technology
基金
国家重点研发计划重点专项(2016YFE0124900)
关键词
复合材料
熔融盐
鳞片石墨
热物性
热导率
composite materials
molten salt
graphite flakes
thermal properties
thermal conductivity
