화학공학소재연구정보센터
Thermochimica Acta, Vol.464, No.1-2, 16-23, 2007
Dynamic effective thermal properties of ceramics-metal functionally graded fibrous composites
This work is dedicated to investigate the dynamic effective thermal properties of ceramics-metal functionally graded fibrous composites resulting from thermal waves. A micromechanics-based thermo-dynamical model is developed to predict the distribution of dynamic effective thermal properties of functionally graded fibrous composites in the gradation direction. Generally speaking, in functionally graded materials there exist two microstructurally distinct zones: fiber-matrix zone and a transition zone. In fiber-matrix zone, based on the heat conduction equation in materials, the dynamic effective thermal properties for any macroscopic material points are determined by employing effective medium method in the corresponding microstructural representative volume element (RVE). In transition zone, a transition function is introduced to make the wave fields continuous and differentiable. Numerical examples of the dynamic effective thermal properties in the gradation direction under different parameters are graphically presented. Obtained results reveal that the material properties of each phase, the incident frequency, and the gradation parameter of materials have great effect on the distribution of dynamic effective properties in the gradation direction. In different material zones, the effect displays great difference. At last, the results are discussed in detail. (c) 2007 Elsevier B.V. All rights reserved.