Abstract
This paper proposes a novel design methodology of graded microstructures of functional composites for the emergence of macroscopic function. Micro-macro correlation is analyzed by the homogenization theory. That is, the homogenized properties such as elastic moduli and coefficients of thermal expansion and thermal conductivity are calculated for arbitrary complex microstructures. Then, the functional composites with graded microstructures can be replaced by a homogenized model. Also because it is impossible to design all of the numerous graded microstructures, a discretized model is adopted. To determine the optimum graded arrangement of the microstructures in the discretized model, the genetic algorithm is adopted in this paper. Next, the design of continuously graded microstructures is completed using a feature-based 3D-CAD system. In addition, a solid model is produced by the stereolithography to help the understanding of the designed complex microstructures. Brief description of the formulation of the homogenization method for heat conduction and thermal stress problems are shown. An example of the design of a plate with graded microstructures in its thickness direction to control the macroscopic temperature distribution, thermal strain distribution and deflection is shown.
