초록 ▼

A moldable composiion comprising a mixture of magnesia, alumina, and silicon carbide powders or agglomerates thereof, the powders having an overall average size of at most 5.0 micrometers, preferably an average size in the range of 0.2 to 2.0 micrometers, optionally a polymeric binder, optionally a

A moldable composiion comprising a mixture of magnesia, alumina, and silicon carbide powders or agglomerates thereof, the powders having an overall average size of at most 5.0 micrometers, preferably an average size in the range of 0.2 to 2.0 micrometers, optionally a polymeric binder, optionally a fluxing agent, and optionally a plasticizer or lubricant which exhibits litle or no controlled dimensional stability upon being fired to a cordierite ceramic material in a novel process. The process involves incorporation of silicon carbide powder into the moldable composition and the reaction of this silicon carbide upon firing to produce silicon dioxide. The cordierite ceramic material is useful where the dimensions of a shaped or molded part must be preserved after firing, as, for example, in the preparation of dental articles or as a mold for casting metals.

대표청구항 ▼

A moldable unfired composition comprising a mixture of 12 to 27 weight percent magnesia, 27 to 45 weight percent alumina, and 37 to 51 weight percent silicon carbide powders of agglomerates thereof, said magnesia, alumina, and silicon carbide powders and agglomerates having an overall average partic

A moldable unfired composition comprising a mixture of 12 to 27 weight percent magnesia, 27 to 45 weight percent alumina, and 37 to 51 weight percent silicon carbide powders of agglomerates thereof, said magnesia, alumina, and silicon carbide powders and agglomerates having an overall average particle size of at most 5.0 micrometers.