EP0072909A2 - Procédé de fabrication d'une couche intermediaire en métal - Google Patents

Procédé de fabrication d'une couche intermediaire en métal Download PDF

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Publication number
EP0072909A2
EP0072909A2 EP82106244A EP82106244A EP0072909A2 EP 0072909 A2 EP0072909 A2 EP 0072909A2 EP 82106244 A EP82106244 A EP 82106244A EP 82106244 A EP82106244 A EP 82106244A EP 0072909 A2 EP0072909 A2 EP 0072909A2
Authority
EP
European Patent Office
Prior art keywords
suspension
intermediate layer
metal powder
pressing
pressing surface
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP82106244A
Other languages
German (de)
English (en)
Other versions
EP0072909B1 (fr
EP0072909A3 (en
Inventor
Werner Dr.-Ing. Hüther
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
MTU Aero Engines AG
Original Assignee
MTU Motoren und Turbinen Union Muenchen GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by MTU Motoren und Turbinen Union Muenchen GmbH filed Critical MTU Motoren und Turbinen Union Muenchen GmbH
Publication of EP0072909A2 publication Critical patent/EP0072909A2/fr
Publication of EP0072909A3 publication Critical patent/EP0072909A3/de
Application granted granted Critical
Publication of EP0072909B1 publication Critical patent/EP0072909B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
    • F01D5/3084—Fixing blades to rotors; Blade roots ; Blade spacers the blades being made of ceramics
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F7/00—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression
    • B22F7/06—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools
    • B22F7/062—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts
    • B22F7/064—Manufacture of composite layers, workpieces, or articles, comprising metallic powder, by sintering the powder, with or without compacting wherein at least one part is obtained by sintering or compression of composite workpieces or articles from parts, e.g. to form tipped tools involving the connection or repairing of preformed parts using an intermediate powder layer
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
    • F01D5/3092—Protective layers between blade root and rotor disc surfaces, e.g. anti-friction layers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy

Definitions

  • the invention relates to an intermediate layer according to the preamble of claim 1.
  • the invention further relates to methods for producing the intermediate layer according to the invention.
  • the rotor blades including their feet, or additionally the rotor disk made of ceramic material.
  • One of the main problems is the connection of the ceramic blade, i.e. of her ceramic foot, too, with the rotor disc, i.e. So in the blade attachment.
  • the types of said groove are known, i.e.
  • the groove generally runs in its longitudinal direction either as a single groove for a foot parallel to the rotor axis or obliquely as in the case of a helical gear or coaxially as an annular groove for all blades or feet of the blade ring.
  • the foot is usually dovetail-shaped or pine-cone-shaped in a cut perpendicular to the longitudinal and insertion direction of the groove in such a way that the above-mentioned, generally planar wings (bearing surfaces) of the foot and the groove, which in this cut have the same shape has, like the foot and into which it is inserted, lie at an acute angle to the rotor-radial foot median plane running in that direction. This flank angle is generally 30 to 75 °. As a result, the wings are pressed obliquely when the centrifugal forces of the rotor blade act.
  • a major difficulty lies in the fact that the brittle, non-plastically deformable ceramic blade, ie its foot or its wings, does not lie or rest along the groove on the wings thereof, which is due to inevitable manufacturing inaccuracies thing is. This often leads to local stress increases, which reduces the breaking speed or the permissible centrifugal load on the blade.
  • One way to reduce or eliminate this disadvantage is to insert a metal foil between the wings.
  • This film by being plastically deformed, at least largely compensates for the manufacturing inaccuracies mentioned and ensures an at least reasonably uniform introduction of force, so that a higher breaking speed or the like and a longer service life can be achieved for the blade.
  • the film reduces the friction between the foot and the groove, so that the risk is reduced that the blade or its foot is jammed in the groove by temperature changes and experiences additional stress.
  • the rotor disc becomes hot during operation, which causes the groove to widen and the blade to move radially outwards, and when it cools, the blade, if the foil is not provided, does not go back due to the friction and the groove width decreases and exerts additional tension on the shovel or its foot.
  • the object of the invention is to reduce or eliminate these disadvantages and. is solved according to the invention by the characterizing part of claim 1.
  • the covering according to the invention builds up or the two coverings according to the invention reduce stress peaks better because this covering or these coverings is more easily deformable than the film by the pressing of the pressing surfaces. Furthermore, the covering or the coverings can be produced with little effort, and the covering adheres firmly to the pressing surface or the two pressing surfaces or the coverings adhere firmly to the two pressing surfaces.
  • the covering or the coverings take the place of the film, so that there is no longer any installation difficulty with a small shovel or small foot. There is also no more slipping of the film.
  • the metal powder suspension mentioned in the invention is applied to the pressing surface or surfaces, where it dries up.
  • a solid portion of the non-metallic component of the suspension can escape, and the coating then remains. It consists of the metal of the metal powder.
  • the metal powder granules have an average grain size of in particular 0.1 ⁇ m to 54 ⁇ m.
  • the invention is generally applied when the pressing or joining point is exposed to thermal stress in addition to the pressing surface pressure.
  • the invention can also be advantageously used when the Press or joint is under pressure of a fluid; the pressing or joining point is generally better sealed with the covering or coverings according to the invention than with the film.
  • the intermediate layer according to the invention is particularly hooked on pressing surfaces, engaging behind or the like. applied to the blade attachments mentioned, where the pressing by pulling then takes place, in these blade attachments by the blade centrifugal force. But it can also e.g. can be used against each other without snagging.
  • the metals or metal mixtures mentioned in claim 2 are the preferred. Which metal or which metal mixture is chosen depends on the operating temperature of the press or joint to be provided with the covering. Regarding the non-metallic constituent of the suspension, claims 3 are generally followed. Furthermore, the suspension is usually thin. Furthermore, the suspension can be applied easily. It is often brushed on.
  • the non-metallic component of the suspension must not have an oxidizing effect on the metal powder when heated.
  • a reducing effect e.g. with the rosin.
  • the intermediate layer e.g. proceeded according to claim 4, but preferably according to claim 5.
  • the capillary forces mentioned in claim 5 bring about a complete filling of the space with the suspension. If one proceeds according to claim 5, manufacturing inaccuracies are largely compensated for even without plastic deformation of the covering, as a result of which stress peaks are reduced particularly effectively. If the procedure is as claimed in claim 7, a coating is formed which largely resists oxidation. Metals oxidizing in air are e.g. Nickel or titanium.
  • the direction mentioned is designated by 10, the middle plane mentioned by 11.
  • the direction 10 runs - see FIG. 2 - obliquely to the circumferential direction - arrow 17 - of the rotor disk 13.
  • the ceramic base 15 of the ceramic axial vane and the associated groove 18 of the metallic rotor disk 13 together with two shown exaggeratedly thick for better visibility, metallic intermediate linings 14 said axial blade attachment.
  • At the foot 15 there is a broken waist-like waiter gear part 16 and on this, which is not shown, a blade platform and the blade on; the SchaufeY D consists of all these parts in one piece.
  • wing 19 is somewhat narrower than the wing 20 and is located at full load of the axial gas turbine as shown in Fig. 1 on both sides at a small distance from the longitudinal edges of the wings 20.
  • a metal powder suspension with a paint as non-metallic constituent is brushed on the outside of the space between the wings 19 and 20 on the long side 23 thereof, and the capillary forces completely fill this space with this suspension.
  • the fill is air dried, i.e. the solvent of the paint evaporates.
  • the dried fill is then heated by the fluid flowing into the bladed flow space, so that the solid portion of the lacquer escapes.
  • the intermediate covering 14 adheres firmly to the wings 19 and 20.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Composite Materials (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP82106244A 1981-08-21 1982-07-13 Procédé de fabrication d'une couche intermediaire en métal Expired EP0072909B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3133158 1981-08-21
DE3133158A DE3133158C1 (de) 1981-08-21 1981-08-21 Pressflaechen-Zwischenlage aus Metall und Verfahren zur Herstellung derselben

Publications (3)

Publication Number Publication Date
EP0072909A2 true EP0072909A2 (fr) 1983-03-02
EP0072909A3 EP0072909A3 (en) 1983-06-15
EP0072909B1 EP0072909B1 (fr) 1986-11-26

Family

ID=6139832

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82106244A Expired EP0072909B1 (fr) 1981-08-21 1982-07-13 Procédé de fabrication d'une couche intermediaire en métal

Country Status (3)

Country Link
US (1) US4471008A (fr)
EP (1) EP0072909B1 (fr)
DE (2) DE3133158C1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2639398A1 (fr) * 1988-11-24 1990-05-25 Mtu Muenchen Gmbh Emplanture d'aube en fibre pour rotor

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DE3306896A1 (de) * 1983-02-26 1984-08-30 MTU Motoren- und Turbinen-Union München GmbH, 8000 München Heissgasbeaufschlagte turbinenschaufel mit metallenem stuetzkern und umgebendem keramischen schaufelblatt
US4728262A (en) * 1986-01-22 1988-03-01 Textron Inc. Erosion resistant propellers
US4790723A (en) * 1987-01-12 1988-12-13 Westinghouse Electric Corp. Process for securing a turbine blade
DE3815977A1 (de) * 1988-05-10 1989-11-30 Mtu Muenchen Gmbh Folienzwischenlage zur fuegung von reibkorrosionsgefaehrdeten maschinenbauteilen
US5135777A (en) * 1990-02-28 1992-08-04 The Babcock & Wilcox Company Method for diffusion coating a workpiece with Cr, Si, Al or B by placing coated ceramic alumino-silicate fibers next to the workpiece and heating to diffuse the diffusion coating into the workpiece
US5264295A (en) * 1990-08-03 1993-11-23 Ngk Spark Plug Co., Ltd. Combined body of ceramics and metal
JP2630490B2 (ja) * 1990-08-03 1997-07-16 日本特殊陶業株式会社 セラミックと金属との結合体
US5364659A (en) * 1992-02-21 1994-11-15 Ohio State University Research Foundation Codeposition of chromium and silicon diffusion coatings in FE-base alloys using pack cementation
US5435694A (en) * 1993-11-19 1995-07-25 General Electric Company Stress relieving mount for an axial blade
US6102664A (en) * 1995-12-14 2000-08-15 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Blading system and method for controlling structural vibrations
DE19728085A1 (de) * 1997-07-02 1999-01-07 Asea Brown Boveri Fügeverbindung zwischen zwei Fügepartnern sowie deren Verwendung
FR2770255B1 (fr) * 1997-10-27 1999-12-03 Gec Alsthom Electromec Rotor pour turbine a vapeur
US6409473B1 (en) 2000-06-27 2002-06-25 Honeywell International, Inc. Low stress connection methodology for thermally incompatible materials
ITMI20032607A1 (it) * 2003-12-29 2005-06-30 Nuovo Pignone Spa Disco di un rotore a dischi per una turbina a gas
US7217099B2 (en) * 2005-05-24 2007-05-15 General Electric Company Coated forward stub shaft dovetail slot
EP1818506A1 (fr) 2006-02-08 2007-08-15 Siemens Aktiengesellschaft Réduction de la fatigue répétitive dans un pied de sapin
US20090068016A1 (en) * 2007-04-20 2009-03-12 Honeywell International, Inc. Shrouded single crystal dual alloy turbine disk
WO2014163709A2 (fr) 2013-03-13 2014-10-09 Uskert Richard C Plate-forme pour aubes de turbine composites à matrice céramique
US10487670B2 (en) * 2013-03-13 2019-11-26 Rolls-Royce Corporation Gas turbine engine component including a compliant layer
US9506356B2 (en) 2013-03-15 2016-11-29 Rolls-Royce North American Technologies, Inc. Composite retention feature
PL3307989T3 (pl) * 2015-08-19 2021-03-08 Siemens Aktiengesellschaft Łopatka turbiny gazowej albo łopatka sprężarki z powłoką anty-frettingową w obszarze podstawy łopatki i wirnik
US10767498B2 (en) 2018-04-03 2020-09-08 Rolls-Royce High Temperature Composites Inc. Turbine disk with pinned platforms
US10577961B2 (en) 2018-04-23 2020-03-03 Rolls-Royce High Temperature Composites Inc. Turbine disk with blade supported platforms
US10890081B2 (en) 2018-04-23 2021-01-12 Rolls-Royce Corporation Turbine disk with platforms coupled to disk

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2639398A1 (fr) * 1988-11-24 1990-05-25 Mtu Muenchen Gmbh Emplanture d'aube en fibre pour rotor

Also Published As

Publication number Publication date
US4471008A (en) 1984-09-11
EP0072909B1 (fr) 1986-11-26
EP0072909A3 (en) 1983-06-15
DE3274478D1 (en) 1987-01-15
DE3133158C1 (de) 1982-12-16

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