Abstract: A nozzle is formed of reaction sintered silicon carbide consisting essentially of silicon carbide and unreacted metallic silicon and having a density of 3.03-3.16 g/cm.sup.3. The nozzle satisfies the requirements of heat, wear, corrosion and chemical resistance and has experienced no volume shrinkage during sintering. The nozzle is suitable for use in a mixing/dispersing arrangement mounted in a fluidized bed reactor.

Abstract: A metal-ceramic composite body is prepared by impregnating a porous ceramic preform with a molten metal. A preform (3, 15), a crucible (7) containing molten metal (6), and a channeling bundle (8) of filaments are set such that one end of the bundle (8) is disposed above the molten metal (6) in the crucible (7) and the other end of the bundle (8) is disposed in contact with the preform (3, 15). The crucible (7) is moved up until the bundle one end is immersed in the molten metal (6) whereby the molten metal (6) is channeled to the preform (3, 15) through the filaments of the bundle (8) for impregnating the preform (3, 15) with the molten metal. The crucible (7) is moved down until the bundle one end is withdrawn from the molten metal (6) whereby supply of the molten metal to the preform (3, 15) is interrupted.