宽温域中碳纤维导热特性研究  

Study on thermal conductivity of carbon fiber in wide temperature range

作　　者：刘学波 董华[1] LIU Xue-bo;DONG Hua(School of Environmental and Municipal Engineering,Qingdao University of Technology,Qingdao 266033,China)

机构地区：[1]青岛理工大学环境与市政工程学院

出　　处：《热科学与技术》2019年第5期392-397,共6页Journal of Thermal Science and Technology

摘　　要：碳纤维作为一种被广泛应用的微纳米材料,对其导热性能的测量研究一直被作为对碳纤维性能研究的重要内容。在利用氦气的气体液化基础上搭建的超低温实验环境中,基于瞬态电热法对处于290到10 K温度内的碳纤维样品的导热性能进行研究。实验发现,当实验温度低于某一特定温度后,材料的热扩散率表现出与声子散射分析相反的实验结果。通过引入热扩散系数倒数这一理论研究声子热阻在低温下的变化,分析得出,当实验环境温度低于某一特定温度后,低温会造成碳纤维材料内的石墨微晶体结构发生变化,从而造成材料热扩散率下降。Carbon fibers are widely used as micro-and nano-materials. The measurement of thermal conductivity of carbon fibers has been regarded as an important part of the research on the properties of carbon fibers. The thermal conductivity of carbon fiber samples in the temperature range of 290 to 10 K was studied by the transient electro-thermal method in a stable low-temperature experimental environment based on helium gas liquefaction technology. It is found that when the experimental temperature is lower than a certain temperature, the thermal diffusivity of the material exhibits contrary to the phonon theory analysis. By introducing the reciprocal of thermal diffusivity to study on the variation of phono thermal resistance at low temperature, it is concluded that the graphite microcrystal structure in carbon fiber material will change when the experimental ambient temperature is lower than a certain temperature, which will result in the decrease of thermal diffusivity of the material.

关 键 词：碳纤维 热扩散系数、导热系数 拉曼光谱 驰豫时间 热阻 

分 类 号：TK142[动力工程及工程热物理—热能工程]