REINFORCEMENT FRACTURE AND TENSILE DUCTILITY IN SPHERE-REINFORCED METAL-MATRIX COMPOSITES

Sphere-reinforced metal-matrix composites are modelled as a three dime nsional array of hexagonal cylinders, each one with a broken or intact spherical reinforcement at its centre. Using this model, the stress-s train response of the composite in uniaxial tension was obtained. A pa rametrical analysis of the influence of matrix and reinforcement prope rties as well as volume fraction on the ductility of these composites was performed. It was found that the decrease in ductility with respec t to the unreinforced matrix depended mainly on the reinforcement/matr ix strength ratio and on the defect distribution in the particulates.