Abstract: A friction welding process providing a workpiece having a weld surface, and a second workpiece having a weld surface. The workpieces being welded together at respective weld surfaces. Oscillatory motion is affected to the workpieces such that one weld surface moves across the other, thereby raising the temperature at the weld surfaces to create a weld interface. The oscillatory motion is ceased and the weld surfaces cool to weld the workpieces together at the interface. The workpiece has an extending portion, and the weld surface is provided on the extending portion. The extending portion includes an apex region, which engages the second workpiece's weld surface. A side face extends from the apex region to provide a gap between the side face and the second workpiece's weld surface. The gap allows weld flash material to pass from the weld interface through said gap.

Abstract: A disk for a BLISK rotary stage of a gas turbine engine includes a stub on the tapered circumferential surface of a turbine disk, the stub defining a weld joint surface on the radially outermost face of the stub. The weld joint surface follows the annulus curvature in axial and circumferential directions while remaining flat in a third direction. A blade is applied radially to the stub and linear friction welding of the blade to the stub is effected by oscillating the blade in said third direction while applying a welding force inwardly along the blade.

Abstract: A method of making a BLISK by linear friction welding, comprises providing a stub on the circumferential surface of a turbine disk and defining a weld joint surface on the radially outermost face of the stub. The weld joint surface follows the annulus curvature in axial and circumferential directions while remaining flat in a third direction. A blade is applied radially to the stub and linear friction welding of the blade to the stub is effected by oscillating the blade in said third direction while applying a welding force inwardly along the blade.

Abstract: A solid oxide fuel cell stack comprises a plurality of first modules and a plurality of second modules stacked alternately. Each first module comprises a first distribution member which defines internal passages for the supply of a first reactant to the fuel cells. The first distribution member is enclosed by a porous support structure which carries the fuel cells on its two parallel surfaces. A plurality of passages are defined between the porous support structure and the first distribution member which distribute and remove the first reactant from the anodes. Each second module comprises a second distribution member which defines internal passages for the supply of a second reactant to the fuel cells. The passages in the first distribution member contain a catalyst for steam reforming the fuel. The catalyst is in intimate thermal contact with the fuel cells. Additionally a low temperature adiabatic preformer supplied with hydrocarbon fuel prereforms the fuel and supplies it to the passages.

Abstract: A solid oxide fuel cell stack includes a core region which comprises a plurality of first modules and a plurality of second modules stacked alternately. Each first module comprises a first distribution member formed from two corrugated ceramic plates which define internal passages for the supply of a first reactant to the fuel cells. The first distribution member is enclosed by a porous support structure which carries the fuel cells on its two parallel surfaces. A plurality of passages are defined between the porous support structure and the first distribution member which distribute and remove the first reactant from the anodes. Each second module comprises a second distribution member formed from two corrugated ceramic plates which define internal passages for the supply of a second reactant to the fuel cells. A plurality of passages are defined between the fuel cells and the second distribution member which distribute and remove the second reactant from the cathodes.

Abstract: A solid oxide fuel cell stack comprises a plurality of first modules and a plurality of second modules stacked alternately. Each first module comprises a first distribution member which defines internal passages for the supply of a first reactant to the fuel cells. The first distribution member is enclosed by a porous support structure which carries the fuel cells on its two parallel surfaces. A plurality of passages are defined between the porous support structure and the first distribution member which distribute and remove the first reactant from the anodes. Each second module comprises a second distribution member which defines internal passages for the supply of a second reactant to the fuel cells. The passages in the first distribution member contain a catalyst for steam reforming the fuel. The catalyst is in intimate thermal contact with the fuel cells. Additionally a low temperature adiabatic preformer supplied with hydrocarbon fuel prereforms the fuel and supplies it to the passages.