Thermo-Mechanical Modeling of Carbon Nanotube Arrays for Thermal Interface Applications

posted Jun 14, 2013, 8:36 AM by Timothy Fisher   [ updated Jun 18, 2013, 10:41 AM by Sridhar Sadasivam ]

Student: Sridhar Sadasivam

Faculty: Timothy S. Fisher

Sponsor: Raytheon/DARPA Nano Thermal Interfaces Program

Summary: A growing interest has developed in the past decade on the use of carbon nanotube (CNT) arrays as thermal interface materials (TIM). This interest on CNT TIMs stems primarily from high thermal conductivity of individual CNTs and mechanical compliance of CNT arrays. Innovative methods for the measurement of mechanical and thermal properties of CNT arrays have been developed by many others. However, modeling of CNT TIMs have mostly been limited to semi-empirical methods without detailed consideration of the CNT array microstructure. We have developed a combined thermo-mechanical model of CNT arrays with coarse-grain methods. The coarse graining of CNTs allows us to model reasonably large numbers of CNTs at practical engineering scales within a reasonable computational time. A mesoscopic thermal network model couples with the coarse grain mechanics model and is used to estimate the diffusive and tip contact resistances of CNT arrays. Other useful information for thermal interface applications such as the effects of surface roughness and fillers such as wax are also expected to be predicted within the framework of the thermal network model.

Representative Paper: