METAL-CERAMIC COMPOSITES VIA IN-SITU METHODS

To overcome some of the inherent problems that are associated with con ventional processes, several in situ methods have been developed to ob tain metal/ceramic composite materials. In this paper recently develop ed processes have been reviewed with a greater emphasis on directed me lt oxidation and nitridation. These methods offer microstructures with varying metal/ceramic combinations. In some processes, metal matrix c omposites dispersed with controlled quantities of ceramic phase(s) are possible whereas in other ceramic composites with isolated/interconne cted metallic dispersions are obtained. They could be varied by contro lling the processing variables, i.e. temperature, time, reactant phase s and filler materials. The properties of in situ processed materials primarily depend on the matrix and the volume fraction of the constitu ent phase. The mechanical properties, toughening mechanisms and potent ial applications are briefly reviewed. (C) 1997 Elsevier Science S.A.