Abstract: Conductive and/or chemically absorptive ceramic fibers are woven with optional non-conductive/non-absorptive ceramic fibers to create a fiber reinforcement which is impregnated with a ceramic-material-producing (pre-ceramic polymer) binder and heated to create the ceramic honeycomb with controlled ohmic loss and/or chemical absorption properties. The desired properties of the honeycomb material can be provided by the conductive and/absorptive ceramic fibers alone or in combination with non-fibrous or fibrous conductive and/or absorptive ceramic material provided by the binder, typically a preceramic polymer which may or may not contain dispersed ceramic materials; after the honeycomb is formed, the non-fibrous or fibrous conductive and/or absorptive ceramic material is interspersed throughout the honeycomb. By heating the impregnated fiber reinforcement in the absence of oxygen, carbon from any carbon-containing materials within the binder remain as a part of the honeycomb material.

Abstract: Conductive and/or chemically absorptive ceramic fibers are woven with optional non-conductive/non-absorptive ceramic fibers to create a fiber reinforcement which is impregnated with a ceramic-material-producing (pre-ceramic polymer) binder and heated to create the ceramic honeycomb with controlled ohmic loss and/or chemical absorption properties. The desired properties of the honeycomb material can be provided by the conductive and/absorptive ceramic fibers alone or in combination with non-fibrous or fibrous conductive and/or absorptive ceramic material provided by the binder, typically a preceramic polymer which may or may not contain dispersed ceramic materials; after the honeycomb is formed, the non-fibrous or fibrous conductive and/or absorptive ceramic material is interspersed throughout the honeycomb. By heating the impregnated fiber reinforcement in the absence of oxygen, carbon from any carbon-containing materials within the binder remain as a part of the honeycomb material.

Abstract: The invention relates to silicon nitride composite articles having improved fracture toughness prepared by forming a composition including small amounts of boron nitride powder in a silicon nitride powder base and processing the composition.

Abstract: An ultrasonic transducer arrangement for inspecting a work piece at an elevated temperature through the use of ceramic delay lines is disclosed. The ceramic material utilized for the delay lines is comprised of a composition of silicon nitride and boron nitride which is hot pressed so that the boron nitride platelets are aligned substantially parallel to the propagation direction of the ultrasonic pulses thus minimizing pulse attenuation. The ceramic material is heat and wear resistant and can be machined so as to conform to the surface of the work piece being inspected.

Abstract: A ceramic fiber-reinforced ceramic heat exchanger includes a tube sheet and one or more coiled, oval cross-section U-tubes formed integrally with the tube sheet, wherein both the tube and tube sheet are composed of a ceramic fiber-reinforced ceramic composition, particularly suited for waste heat recovery in harsh flue gas environments.

Abstract: A means for producing nitride bonded refractory shapes, in situ, by mixing an aluminum metal powder, relatively pure silica and a refractory aggregate. The mixes are pressed into shapes and burned at elevated temperatures in a nitriding atmosphere to form the bond.

Abstract: A means for producing nitride bonded refractory shapes, in situ, by mixing an aluminum metal powder, relatively pure silica, crude clay and a refractory aggregate. The mixes are pressed into shapes and burned at elevated temperatures in a nitriding atmosphere to form the bond.