Applying a micromechanics approach for predicting thermal conducting properties of carbon nanotube-metal nanocomposites

Abstract

Heat dissipation is a very important issue in the harsh thermal loads affecting the reliability of structures. In this study, the thermal conducting behavior of carbon nanotube (CNT)-reinforced metal matrix nanocomposites (MMNCs) has been analyzed using a micromechanical model based on the method of cell (MOC) approach. The critical role of interfacial thermal resistance between the CNT and metal matrix in the MMNC thermal conducting response has been extensively explored. Also, the effects of volume fraction, length, diameter and curvature of CNTs have been investigated. It has been found that forming a perfect CNT/matrix interface contact would enhance remarkably the overall thermal conductivities. Generally, the axial thermal conductivity of the CNT-reinforced MMNCs can be increased with (i) rising CNT length and (ii) using straight CNTs. Moreover, the transverse thermal conductivity of these nanocomposite materials are improved with (i) rising CNT diameter and (ii) using wavy CNTs. Besides, increasing CNT volume fraction leads to a significant increment in the effective thermal conductivities in the presence of a perfect bonding at the CNT/matrix interface. Effective thermal conductivities of the MMNCs estimated by the MOC approach have been compared with those predicted by the effective medium and Halpin-Tsai models. A quite good agreement has been observed between the predictions of the MOC approach and experimental data.