DISLOCATION CONFIGURATIONS IN METAL-MATRIX COMPOSITES CORRELATED WITHNUMERICAL PREDICTIONS

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