Interfacial Thermal Resistance

When: Thursday, February 06, 2014 at 10:30 am
Where: DG 50
Speaker: Professor Pawel Keblinski
Organization: Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY
Sponsor: Distinguished Lecture in Nanotechnologies through Materials Innovation, Co-hosted by Mechanical and Industrial Engineering, Chemical Engineering, and Physics Departments

The interface between two dissimilar materials poses a thermal resistance associated with different characteristics of electrons and/or phonons that carry the heat in the two materials. Apart form fundamental interest, the interfacial resistance has important practical implications, particularly when the microstructural features, such as grain size in nanocrystalline materials or the fiber diameter in nanocomposites, becomes comparable with the phonon mean free path. In such a case, the thermal transport is determined mostly by thermal properties of interfaces rather than intrinsic bulk properties. While the interfacial resistance can be detrimental, e.g., by limiting the thermal conductivity of composite materials, it can be also desirable, e.g., to improve the performance of thermal barrier coatings or thermoelectric materials.

In our presentation, we will describe an emerging framework and understanding of the interfacial thermal resistance beyond standard conceptual models that account only for the property mismatch between the two materials forming the interface. In particular, we will focus our attention on the relationship between the interfacial bonding and interfacial transport. We will also demonstrate the highly non-equilibrium nature of heat flow across interfaces, particularly those characterized by weak bonding, and show how such behavior can be explored to characterize frequency dependent thermal coupling between biomolecules and water.

Bio-Sketch: Dr. Keblinski is a professor in the Materials Science and Engineering Department at Rensselaer Polytechnic Institute (RPI). He received his MS degree in Physics from the University of Warsaw and his Ph.D. degree in Physics from the Pennsylvania State University. Prior to his RPI appointment, he was a postdoctoral researcher at Argonne National Laboratory and Forschungszentrum Karlsruhe.  Dr. Keblinski is using atomic-level computational methods, including classical molecular dynamics and Monte-Carlo simulations, and atomic vibration analysis to study structure-property relationships, most notably, in interfacial materials.  His main research focus is on modeling thermal transport at interfaces and in nano-structured materials, including carbon nanomaterials, polymer nanocomposites, and suspensions of solid particles. His atomic-level simulations and calculations are augmented with continuum-level modeling and homogenization analysis to provide information on system behavior and properties at larger scales. His work to date led to over 90 invited presentations and over 160 publications in peer-reviewed journals. He is a recipient of NSF Career Award, Humboldt Fellowship, and 3 RPI School of Engineering Research Awards.