碳包铝纳米颗粒/石蜡复合相变导热材料的制备及其热学性能研究

Preparation and thermalproperties of carbon coated aluminum/paraffin wax composite

采用直流碳弧法制备碳包铝纳米颗粒,并将其分散于石蜡（PW）基底中以制备碳包金属铝/石蜡复合相变材料.运用X射线衍射分析、扫描电子显微镜及透射电子显微镜等分析方法,研究碳包铝纳米粒子的微观形貌结构;利用差示扫描量热法及热失重分析方法,研究碳包金属铝纳米粒子和碳包铝/石蜡复合相变材料的热学特性、热稳定性以及热传导性能.结果表明：制备的金属铝纳米粒子呈现类球状核壳型结构,粒径范围在50~100nm;相比纯石蜡,碳包铝/PW复合相变材料的分解温度提高至230℃,并且复合相变材料的相变特性无明显变化;碳包金属铝/PW复合相变材料的导热系数比纯石蜡增长了194.4%,提高到0.21 W/（m·K）.

In this paper,carbon coated aluminum nanoparticles were prepared by direct current discharge method.Carbon coated aluminum/paraffin wax phase-change composites were fabricated by dispersing the carbon-coated aluminum nanoparticles in the paraffin wax（PW）matrix.X-ray diffraction（XRD）,scanning electron microscope（SEM）and transmission electron microscope（TEM）analysis methods were employed to investigate the morphology and microstructure of carbon-coated aluminum nanoparticles.The thermal properties,thermal stability and thermal conductivity of carbon-coated aluminum nanoparticles and carbon-coated aluminum/PW composites were studied by DSC,TG and laser flash methods.The results show that the carbon-coated aluminum nanoparticles exhibite core-shell sphere structure,and the size of carbon-coated aluminum nanoparticles are 50-100 nm in diameter.Compared with pure paraffin,the onset decomposition temperature of carbon-coated aluminum/PW composite increases to 230℃,and the addition of carbon-coated aluminum causes less influence on phase change characteristic of carbon-coated aluminum/PW composite.Moreover,the thermal conductivity of carbon-coated aluminum/PW composite gains a significant enhancement about 194.4%.