Refractories of silicon carbide and related materials having a modified silicon nitride bonding phase.

摘要

A refractory that is highly resistant to sequential steam oxidation and molten alkali attack is formed by reaction nitriding a mixutre of granular silicon carbide (as defined in the specification), silicon metal and aluminum metal. The refractory is suitable as a blast furnace lining, and comprises a bonded silicon carbide material consisting essentially of granular silicon carbide and a bonding phase comprising Si₃N₄ modified by the presence of oxygen and aluminum to form a sialon, said material having a resistance to at least one of either (a) a molten K₂C0₃ attack alone or (b) a steam oxidation followed by a molten K₂C0₃ attack, which resistance in excess of that possessed by a similar material in which the Si₃N₄ bonding phase is not modified by the presence of oxygen and aluminum.