Degradation of metal matrix composite under plastic straining

Abstract

This chapter discusses the degradation of metal matrix composite under plastic straining. Metal matrix composites (MMC) reinforced with particle or short fiber dispersions are new structural materials that have high specific strength and may take the place of steel structures. However, the MMCs have not yet been put to practical use though some trial products have been made in various industrial fields. The MMCs, especially particle reinforced MMCs, are generally fabricated by either liquid phase methods, those are melt stirring, rheocasting, compocasting, and spray deposition methods or solid phase methods; mainly the powder process like a powder extruding, a hot pressing, a HIP process. The MMC will be subjected to various loading during the deformation processing as well as in using them as structural parts. It is predictable, in this case, that the internal stress and strain distributions under the external loading are much complicated as compared with the conventional metals. Therefore, microstructural degradation, such as microcrack, can occur because of stress localization. However, to apply the deformation processing to MMCs, the influences of various factors of matrix, particles, and their interfaces that depend on their fabricating processes on the macro- and microscopic degradation during plastic straining must be cleared.