Abstract: A method of friction welding a first component to a second component, the method having the steps of: rotating the first component relative to the second component about a rotation axis; and bringing the first component into contact with the second component; wherein, while the first component and the second component are in contact, a first average force is applied during a first stage of the friction welding process and a second average force is applied during a second stage of the friction welding process; and the second average force is different from the first average force.

Abstract: A method of joining a first component to a second component at respective connection surfaces, comprising, in order, applying a local surface treatment to the connection surface of at least one of the first and second components in order to locally alter the microstructure to a depth of between 60 ?m and 10 mm below the connection surface; and joining the first component to the second component using a welding process.

Abstract: A method of friction welding a first workpiece to a second workpiece, includes the first workpiece with a first faying surface having a first faying length, the second workpiece with a second faying surface having a second faying length, the second faying length greater than the first faying length; positioning the first workpiece adjacent the second workpiece; reciprocating the first workpiece and the second workpiece against one another, the first faying moves relative to the second faying by a sweep length, a temperature at the first and second faying surfaces increases to create a weld interface; each of the first and second workpieces are consumed into the weld interface, adjusting the sweep length the sweep length remains equal to a difference between the second and the first faying lengths; and stopping the reciprocating and allowing the first and second workpieces to cool to weld the first and second workpieces together.

Abstract: A method of joining a first component to a second component at respective connection surfaces, comprising, in order, applying a local surface treatment to the connection surface of at least one of the first and second components in order to locally alter the microstructure to a depth of between 60 ?m and 10 mm below the connection surface; and joining the first component to the second component using a welding process.

Abstract: A method of friction welding a first component to a second component, the method having the steps of: rotating the first component relative to the second component about a rotation axis; and bringing the first component into contact with the second component; wherein, while the first component and the second component are in contact, a first average force is applied during a first stage of the friction welding process and a second average force is applied during a second stage of the friction welding process; and the second average force is different from the first average force.

Abstract: A rotary friction welding process is provided, including: providing a first axisymmetric workpiece having a first annular weld surface, and a second axisymmetric workpiece having a second annular weld surface; and rotationally welding the workpeices. On the longitudinal section through the aligned workpieces, each of the first and second annular weld surfaces is flanked by radially inner and outer side surfaces, the first weld surface and its side surfaces being shaped to thermally match the second weld surface and its side surfaces across a line of initial contact of the first and second weld surfaces such the heat flows from the weld at all the side surfaces are substantially equal.

Abstract: The present disclosure provides a rotary friction welding process including: providing an outer axisymmetric workpiece having a front first annular weld surface at a radially inward extent and a rear first annular weld surface at a radially inward extent; providing a front inner axisymmetric workpiece, the front inner workpiece having a front second annular weld surface at a radially outward extent of the front inner workpiece; providing a rear inner axisymmetric workpiece, the rear inner workpiece having a rear second annular weld surface at a radially outward extent of the rear inner workpiece; and rotary welding the workpieces together.

Abstract: A method of friction welding a first workpiece to a second workpiece, includes the first workpiece with a first faying surface having a first faying length, the second workpiece with a second faying surface having a second faying length, the second faying length greater than the first faying length; positioning the first workpiece adjacent the second workpiece; reciprocating the first workpiece and the second workpiece against one another, the first faying moves relative to the second faying by a sweep length, a temperature at the first and second faying surfaces increases to create a weld interface; each of the first and second workpieces are consumed into the weld interface, adjusting the sweep length the sweep length remains equal to a difference between the second and the first faying lengths; and stopping the reciprocating and allowing the first and second workpieces to cool to weld the first and second workpieces together.

Abstract: A workpiece for use with a friction welding process comprises a weld surface. The weld surface comprises a central ridge surface extending along the weld surface, with the central ridge surface being flanked on either side respectively by a first pyramidal surface and a second pyramidal surface. The first pyramidal surface subtends a first pyramidal angle with the central ridge surface, and the second pyramidal surface subtends a second pyramidal angle with the central ridge surface. The first pyramidal surface is further flanked by a third pyramidal surface, and the second pyramidal surface is further flanked by a fourth pyramidal surface, with the third pyramidal surface subtending a third pyramidal angle with the central ridge surface, and the fourth pyramidal surface subtending a fourth pyramidal angle with the central ridge surface. Each of the third pyramidal angle and the fourth pyramidal angle is less than 90°.

Abstract: A method for welding together pieces which form a curved or angled end product using a friction welding process. The method includes: providing first and second pieces which together define the end product geometry, each piece including an end product geometry portion and a sacrificial weld portion, the sacrificial weld portion forming a dog-leg relative to the end product geometry portion and terminating in a planar weld interface surface. The pieces are arranged with their planar weld interface surfaces together at a weld surface interface and the sacrificial weld portions in coaxial alignment. Mechanical friction is applied between the planar weld interface surfaces sufficient to plastically deform the sacrificial weld portions. An axial force is applied along the co-axis of the sacrificial weld portions sufficient to upset the sacrificial weld portions and bring together the end product geometry portions. The sacrificial geometry portions are removed to provide the end product.

Abstract: A friction welding process includes: providing a first workpiece having a first weld surface, and a second workpiece having a second weld surface; aligning the workpieces with the weld surfaces facing each other, moving one workpiece relative to the other workpiece, and engaging the first and second weld surfaces such that the movement raises the temperature at the weld surfaces to create a weld interface; and ceasing the movement and allowing the weld interface to cool to weld the workpieces together at the interface. The first workpiece has a plurality of flash removal channels formed in and/or adjacent to the first weld surface. The channels provide pathways for ejection of material from the weld interface during welding.

Abstract: A method (56) for fabricating an integral assembly (24) is disclosed. The method comprises providing (56) a first workpiece (26) having a first surface and a second workpiece (30) having a second surface (54), performing a first bonding process between the first surface of the first workpiece (26) and the second surface (54) of the second workpiece (30) the bulk material of the first workpiece having a friction weld property that makes it more difficult to weld than a friction weld property at the surface.

Abstract: A workpiece for use with a friction welding process comprises a weld surface. The weld surface comprises a central ridge surface extending along the weld surface, with the central ridge surface being flanked on either side respectively by a first pyramidal surface and a second pyramidal surface. The first pyramidal surface subtends a first pyramidal angle with the central ridge surface, and the second pyramidal surface subtends a second pyramidal angle with the central ridge surface. The first pyramidal surface is further flanked by a third pyramidal surface, and the second pyramidal surface is further flanked by a fourth pyramidal surface, with the third pyramidal surface subtending a third pyramidal angle with the central ridge surface, and the fourth pyramidal surface subtending a fourth pyramidal angle with the central ridge surface. Each of the third pyramidal angle and the fourth pyramidal angle is less than 90°.

Abstract: A rotary friction welding process is provided, including: providing a first axisymmetric workpiece having a first annular weld surface, and a second axisymmetric workpiece having a second annular weld surface; and rotationally welding the workpeices. On the longitudinal section through the aligned workpieces, each of the first and second annular weld surfaces is flanked by radially inner and outer side surfaces, the first weld surface and its side surfaces being shaped to thermally match the second weld surface and its side surfaces across a line of initial contact of the first and second weld surfaces such the heat flows from the weld at all the side surfaces are substantially equal.

Abstract: The present disclosure provides a rotary friction welding process including: providing an outer axisymmetric workpiece having a front first annular weld surface at a radially inward extent and a rear first annular weld surface at a radially inward extent; providing a front inner axisymmetric workpiece, the front inner workpiece having a front second annular weld surface at a radially outward extent of the front inner workpiece; providing a rear inner axisymmetric workpiece, the rear inner workpiece having a rear second annular weld surface at a radially outward extent of the rear inner workpiece; and rotary welding the workpieces together.

Abstract: A method for friction welding of inter alia coarse grain superalloy components, involving conditioning a shear zone of components to be welded by; a) pre-determining temperature profile for which the material of the shear zone of the components approaches viscoplasticity but does not undergo undesirable phase transformations, b) introducing friction at one or both surfaces of the components to be welded to provide a pre-defined quantum of energy sufficient to generate a peak temperature of the temperature profile at that surface whilst simultaneously applying pressure to the surfaces which is below a pressure which will cause upset at the surface, c) withdrawing the friction and/or pressure allowing the heat to disperse by conduction through the shear zone; d) after the temperature at the surface falls below peak temperature, repeating steps b) and c); and repeating step d) as necessary until the pre-determined temperature gradient is achieved throughout the shear zone.

Abstract: A method for welding together pieces which form a curved or angled end product using a friction welding process. The method includes: providing first and second pieces which together define the end product geometry, each piece including an end product geometry portion and a sacrificial weld portion, the sacrificial weld portion forming a dog-leg relative to the end product geometry portion and terminating in a planar weld interface surface. The pieces are arranged with their planar weld interface surfaces together at a weld surface interface and the sacrificial weld portions in coaxial alignment. Mechanical friction is applied between the planar weld interface surfaces sufficient to plastically deform the sacrificial weld portions. An axial force is applied along the co-axis of the sacrificial weld portions sufficient to upset the sacrificial weld portions and bring together the end product geometry portions. The sacrificial geometry portions are removed to provide the end product.

Abstract: A friction welding process includes: providing a first workpiece having a first weld surface, and a second workpiece having a second weld surface; aligning the workpieces with the weld surfaces facing each other, moving one workpiece relative to the other workpiece, and engaging the first and second weld surfaces such that the movement raises the temperature at the weld surfaces to create a weld interface; and ceasing the movement and allowing the weld interface to cool to weld the workpieces together at the interface. The first workpiece has a plurality of flash removal channels formed in and/or adjacent to the first weld surface. The channels provide pathways for ejection of material from the weld interface during welding.

Abstract: A method of linear friction welding, the method comprising: a friction phase comprising oscillating a first workpiece (2) relative to a second workpiece (4) with a surface of the first workpiece (2) being forced against a surface of the second workpiece (4), such that a plasticised layer is formed at the interface between the first and second workpieces (2, 4); wherein the friction phase is divided into a plurality of sub-phases, each sub-phase being configured to form a plasticized layer at the interface between the first and second workpieces (2, 4), each plasticized layer comprising a stagnation zone (10a, 10b); wherein the stagnation zone (10a) of one sub-phase is offset from the stagnation zone (10b) of another sub-phase.

Abstract: A method is disclosed for controlling a process in which a component 4 is moved relative to another component 6 such that at least one of the components 4, 6 experiences a reduction in magnitude in at least one dimension. Such processes may include for example friction welding. The method comprises monitoring energy input to the process and adjusting an input parameter for the process based on the monitored energy input. The monitoring of energy input is performed before any reduction in component magnitude has begun to take place.