On the effect of particle shape and orientation on elastic properties of metal matrix composites

In this investigation, an aluminum alloy, Al 2124-T6, matrix composite containing alumina particles is examined. Both a standard mechanical approach and the homogenization method are employed to calculate effective elastic material constants. A periodic cubic array of particles is assumed leading to three-dimensional finite element analyses. Effective elastic properties are determined. The ceramic particles are assumed to be of four shapes: spherical, cylindrical, cubic and rectangular parallelepiped. For the latter two particles, the effect of particle orientation is examined. These lead to a lack of symmetry which produce effective elastic constants which are not usually observed. Rectangular parallelepiped particles appear to produce some benefits for effective axial elastic moduli.