Abstract
Many kinds of ceramic composites have been studied to improve the mechanical properties. In order to achieve the excellent properties, it is important to finely and homogeneously disperse the second phase in the matrix. The use of composite particles is a promising approach. The fine composite powders of SiC and Si3N4 systems were prepared by vapor phase reaction methods. The sintering of them produced the nanocomposites. The fine dispersion of h-BN particles was effective to improve the thermal shock resistance of SiC and Si3N4. MoSi2-SiC composite powder was prepared by a carbothermal reduction method. High hardness and fracture toughness were achieved by fine-grained microstructure and dispersion of fine SiC particles in MoSi2. Ni-coated TiC particles were prepared by a chemical plating method. The mechanical properties of the sintered body were improved by the homogeneous distribution of TiC particles in Ni matrix. A12O3 particles were coated with fine Ni powder by an agglomeration coating method, and the porous sintered bodies were produced by sintering. Molten metals (Ni and Cu) easily infiltrated into the porous bodies, giving the homogeneous composites of A12O3-metal systems.
