DISLOCATION CONFIGURATIONS IN METAL-MATRIX COMPOSITES CORRELATED WITH NUMERICAL PREDICTIONS

The development of deformation microstructures is reported in reinforced powder-consolidated aluminium. This study discusses observations of the effect of additions of SiC whiskers or particles on the microstructural evolution in the strain range 0.01-0.1. For whisker-containing materials the microstructural changes introduced by thermal cycling have also been investigated, and supplemented by measurements of the dislocation density and microhardness. In plastically deformed specimens the size, shape and microstructure of the deformation zone near the reinforcement have been characterized as a function of the imposed strain. The experimental observations have been compared to finite element model predictions of the stress and strain distribution in the uniaxially loaded composite, and good qualitative agreement has been found. This comparison also points to areas for future model development.