MULLITE BODIES AND METHODS OF FORMING MULLITE BODIES.

摘要

A mullite composition is comprised substantially of mullite grains that are essentially chemically bound wherein the composition h as at least two adjoining regions that have substantially different microstructures. The composition may be produced by forming a mixture of one or more precursor compounds having the elements present in mullite; shaping the mixture into a porous green shape applying a nucleation control agent to a portion of the porous green shape and then heating the porous green shape under an atmosphere and to a temperature sufficient to form the mullite composition.