Abstract: The connection of a ceramic rotary component to a metallic rotary component for a turbomachine such as a gas turbine engine wherein the ceramic rotary component comprises a sintered rotor disk of reaction bonded silicon nitride (RBSN) or silicon carbide sintered under no pressure and the metallic rotary component is formed by the hot isostatic pressing of a metallic powder. The metallic rotary component becomes bonded to the sintered rotor disk to form a secure connection therewith. The metallic powder has a coefficient of thermal expansion substantially equal to that of the ceramic rotary component.

Abstract: A gas turbine power plant, such as a gas turbine engine for a motor vehicle, having a gas turbine, a combustor for producing hot gas to drive the turbine, and an air compressor for furnishing compressed air to the combustor. A heat exchanger, such as a rotary regenerator or a cross-flow recuperator, is located between the air compressor and the combustor for heating air by exhaust gas from the turbine before the air enters the combustor. The air leaving the exit of the heat exchanger decreases in temperature in a direction from one end of the exit to the other. A plurality of separate ducts conduct air from successive areas along the length of the heat exchanger exit to corresponding successive regions along the length of the combustor, the air temperature being lower in each succeeding duct. The lowest temperature air is conducted to the region containing a forward portion, e.g.