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 ageing treatments, has been found to influence the strength of a SiC particulate MMC. Experimental observations of this effect have been successfully compared with theoretical predictions using a self-consistent model based on Eshelby's equivalent inclusion method. The level of damage accumulation has been measured using modulus change experiments. The modulus is found to increase linearly with the level of plastic strain and is dependent on matrix strength. However, this effect does not fully account for the loss of strengthening exhibited by the composites at higher strains.