Gradient Material Design of Particulate Reinforced Composite Structures

The structural integrity of gradient composite materials is determined by the distribution of the reinforcing phase and the individual property of each constituent phase. The desired distribution of the reinforcing phase, however, is a function of the loading and boundary conditions. An approach is presented here whereby the required distribution and properties of the reinforcement phase are obtained for minimizing the stresses in axisymmetric bodies subjected to temperature gradients and pressure differentials. Local effective properties at an arbitrary concentration of the second phase are derived by a homogenization scheme, and inhomogeneous material properties are obtained through the use of distribution functions that relate the concentration of the reinforcement phase to the coordinates of the structure. Using these properties, inhomogeneous eigen-strained media analyses are conducted for graded material cylinders. In this fashion, the desired shape and material properties of the reinforcement phase and its desired distribution can be determined.