摘要:
Actuators utilising shape memory alloy materials are known with regard to gas turbine engines. Such shape memory alloys have been used with respect to deformation provided in vanes and blades as well as nozzle elements in order that variations can be made in engine configuration dependent upon thermal cycling. Unfortunately, pedestals in order to provide spacing between the shape memory alloy and an antagonistic bias has resulted in uneven stress distribution as well as a higher thermal mass for the shape memory alloy. An uneven stress distribution will limit operational life whilst a higher thermal mass will result in slower reaction times. By separation of the shape memory alloy or material from its antagonistic bias through use of a slide element, a reduction in thermal mass is achieved and, more importantly, stress differentiation across the actuator is reduced.
摘要:
An actuator (12) is disclosed for example controlling gas flow in a gas turbine engine. The actuator (12) comprises a first portion (14) having shape memory properties, and a second portion (16) formed of substantially the same material as the first portion and having reduced shape memory properties relative to the first portion. The first portion (14) is movable from a first position to a second position at a temperature above the phase transition temperature of the shape memory material of the first portion (14). The second portion (16) is arranged to urge the first portion (14) from the second position to the first position at a temperature below the phase transition temperature of the shape memory material.
摘要:
An actuator (12) is disclosed for example controlling gas flow in a gas turbine engine. The actuator (12) comprises a first portion (14) having shape memory properties, and a second portion (16) formed of substantially the same material as the first portion and having reduced shape memory properties relative to the first portion. The first portion (14) is movable from a first position to a second position at a temperature above the phase transition temperature of the shape memory material of the first portion (14). The second portion (16) is arranged to urge the first portion (14) from the second position to the first position at a temperature below the phase transition temperature of the shape memory material.
摘要:
A method for joining components comprises locating a region, such as an end region 24, of a shape memory alloy (SMA) material component 10 adjacent to a further component 12, and generating localized plastic deformation of the aforesaid region to create a joint between the components 10, 12. The localized plastic deformation of the shape memory alloy material component 10 is preferably generated by applying a shock load to the shape memory alloy material component 10.
摘要:
An actuator (12) is disclosed for example controlling gas flow in a gas turbine engine. The actuator (12) comprises a first portion (14) having shape memory properties, and a second portion (16) formed of substantially the same material as the first portion and having reduced shape memory properties relative to the first portion. The first portion (14) is movable from a first position to a second position at a temperature above the phase transition temperature of the shape memory material of the first portion (14). The second portion (16) is arranged to urge the first portion (14) from the second position to the first position at a temperature below the phase transition temperature of the shape memory material.
摘要:
Actuators utilising shape memory alloy materials are known with regard to gas turbine engines. Such shape memory alloys have been used with respect to deformation provided in vanes and blades as well as nozzle elements in order that variations can be made in engine configuration dependent upon thermal cycling. Unfortunately, pedestals in order to provide spacing between the shape memory alloy and an antagonistic bias has resulted in uneven stress distribution as well as a higher thermal mass for the shape memory alloy. An uneven stress distribution will limit operational life whilst a higher thermal mass will result in slower reaction times. By separation of the shape memory alloy or material from its antagonistic bias through use of a slide element, a reduction in thermal mass is achieved and, more importantly, stress differentiation across the actuator is reduced.
摘要:
A particle damper is formed using a solid freeform manufacturing technique. A filler provides support for the closing wall of the cavity as it is formed. Apertures allow at least a portion of the filler to be removed. A particle fill of between 90 and 95% is achieved either by removing sufficient filler to reach this fill or removing excess filler and re-filling with damping particles.
摘要:
An atmospheric shield for isolating a component from an external atmosphere is provided. The atmospheric shield includes an envelope and a base carrying a continuous channel. The base and the envelope are arranged to define an enclosure within which the component to be isolated is located, and such that a portion of the envelope extends within the continuous channel. A seal is provided within the continuous channel to seal between the envelope and the base.
摘要:
A method of inspecting an article includes: applying an organic liquid substance over at least a portion of the article to be inspected so as to form a surface layer thereon, wherein said surface layer is luminescent; irradiating the article with the surface layer thereon; and scanning the article to determine its shape.
摘要:
A method of forming a component from solid freeform fabrication comprising the step of building an integral support around the component during manufacture thereof. The stiffness the support provides to the component is selected to minimize deformation of the component either during the manufacture of the component or during a subsequent heat treatment process.