氮化铝基复合相变材料的制备及性能研究

Preparation and properties of composite phase change materials based on aluminum nitride

利用氮化铝材料的高导热的特性,采用造孔剂法烧制出多孔氮化铝材料,再采用真空吸附法吸附正十八烷相变材料制备正十八烷/氮化铝复合相变材料。采用扩散-渗出圈法确定出烧制多孔氮化铝材料所需粉料的最佳配比,并对正十八烷/氮化铝复合相变材料进行了DSC、SEM、FT-IR、TG及导热系数测试。结果表明:粉料中氮化铝含量为50%,造孔剂含量为30%是最佳配比量,烧制出来的多孔氮化铝材料不易坍塌,且吸附率为42.92%;多孔氮化铝材料内部的孔隙完全被正十八烷填满,没有多余的孔隙;复合相变材料具有良好的化学稳定性和热稳定性;复合相变材料的导热系数为2.031 W/(m·K),具有良好的导热性。因此,制备的正十八烷/氮化铝复合相变材料应用于建筑内部,具有良好的节能性。

The porous aluminum nitride material was prepared via the pore-forming method by utilizing the high thermal conductivity of the aluminum nitride material,vacuum adsorption method was adopted to combine porous aluminum nitride and n-octadecane into n-octadecane/aluminum nitride composite phase change material.The optimal ratio of powder required for firing porous aluminum nitride material was determined by diffusion-oozing circle test,a series of tests contain DSC,SEM,FT-IR,TG and thermal conductivity were carried to investigate the performance of n-octadecane/alumminum nitride composite phase change material.The results show that with the content of aluminum nitride and pore former is 50%and 30%,respectively.The fired porous aluminum nitride material is not easy to collapse,the adsorption amount is 42.92%;the pores inside the aluminum nitride material are all filled with n-octadecane;the composite phase change material has good chemical and thermal stability;the composite phase change material has a high thermal conductivity with the value of 2.031 W/(m·K).Therefore,the prepared n-octadecane/aluminum nitride composite phase change material can be applied to the interior of the building and will greatly decrease energy consumption.