INFLUENCE OF MATRIX STRENGTH AND DAMAGE ACCUMULATION ON THE MECHANICAL RESPONSE OF A PARTICULATE METAL-MATRIX COMPOSITE

The strain hardening characteristics of a metal matrix, for various ag eing treatments, has been found to influence the strength of a SiC par ticulate MMC. Experimental observations of this effect have been succe ssfully compared with theoretical predictions using a self-consistent model based on Eshelby's equivalent inclusion method. The level of dam age accumulation has been measured using modulus change experiments. T he modulus is found to increase linearly with the level of plastic str ain and is dependent on matrix strength. However, this effect does not fully account for the loss of strengthening exhibited by the composit es at higher strains.