Abstract: A valve for an internal combustion engine formed of ceramic material for resistance to corrosion, heat and wear. The valve may include a valve tip, a lock groove, a valve stem, a valve fillet, a valve face, a valve margin and a valve head. Certain portions of the valve, such as the valve tip, the lock groove and the valve stem may, alternatively, be formed of metal. The ceramic material includes, among other compositions, silicon nitride, silicon carbide, aluminum nitride, silicon oxynitride, silicon aluminum oxynitride and silicon nitride-silicon carbide.

Abstract: An apparatus for making a single crystal which includes a sealed vessel, a crucible received in the sealed vessel to hold a molten liquid and a floating member having an opening for defining the cross sectional outline of a single crystal while being grown and floating on the molten liquid. The floating member is made from a sintered body consisting essentially of at least one of the oxides of yttrium and the lanthanum series elements, aluminum oxide, aluminum nitride and silicon nitride each in a prescribed amount.