ABSTRACT
The thermal properties of two-layered materials composed of a polymer layer embedded with dielectric AlN particles (AlN composite) coated on top of an aluminum (Al) substrate were investigated by light flash analysis (LFA). The thermal conductivity of the specimens was measured as a function of the AlN composite volume fraction along the thickness direction. By observing the microstructure of the two-layered materials in cross section, we found a tremendous number of randomly distributed pores and boundaries in the AlN composite. Compared to the conventional thermal resistor model, the thermal conductivity values of the specimens measured by LFA were significantly different. When the solid solution model was applied in this study, however, the measured thermal conductivity of the specimens showed good agreement with the values from the solid solution model. The good agreement in thermal conductivities for the specimens was due to the presence of many randomly distributed pores and boundaries in the AlN composite.
(Received October 6, 2016; Accepted December 10, 2016)
keyword : thermal conductivity, layered materials, thick film, thickness direction, thermal property
