EP2147134A1 - Procédé de décapage d'un élément structurel - Google Patents

Procédé de décapage d'un élément structurel

Info

Publication number
EP2147134A1
EP2147134A1 EP08758017A EP08758017A EP2147134A1 EP 2147134 A1 EP2147134 A1 EP 2147134A1 EP 08758017 A EP08758017 A EP 08758017A EP 08758017 A EP08758017 A EP 08758017A EP 2147134 A1 EP2147134 A1 EP 2147134A1
Authority
EP
European Patent Office
Prior art keywords
component
stripped
electrolyte
wear protection
surfactant
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.)
Withdrawn
Application number
EP08758017A
Other languages
German (de)
English (en)
Inventor
Anton Albrecht
Wolfgang Eichmann
Georgios Paronis
Thomas Uihlein
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 Aero Engines 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 Aero Engines GmbH filed Critical MTU Aero Engines GmbH
Publication of EP2147134A1 publication Critical patent/EP2147134A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
    • C25F5/00—Electrolytic stripping of metallic layers or coatings
    • 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
    • F01D5/005—Repairing methods or devices

Definitions

  • the invention relates to a method for stripping a component, in particular a gas turbine component, according to the preamble of claim 1.
  • Components of a gas turbine such as the rotor blades, are provided with special anti-wear coatings to provide oxidation resistance, corrosion resistance, or erosion resistance on the surfaces.
  • the components of gas turbines are subject to wear during operation of the same or can be damaged in any other way.
  • it is generally necessary to remove or remove the wear-resistant coating from the part to be repaired in regions, partially or even in total.
  • the removal or removal of coatings is also referred to as stripping. In the stripping process, a distinction is made between those in which the stripping takes place mechanically, chemically or electrochemically.
  • wear protection coatings are designed as so-called multilayer coatings consisting of several alternately applied to the gas turbine component layers. It is thus possible, for example, for a wear protection coating designed as a multilayer coating to comprise a relatively soft, metallic layer and a relatively hard, ceramic layer, which are applied to the gas turbine component repeatedly alternately one behind the other.
  • wear protection coatings are known in practice in which more than two different layers are alternately applied one behind the other to the gas turbine component, for example multi-layer coatings of four alternately successively applied to the gas turbine component layers, namely a first, to the material composition of the gas turbine component adapted metallic and thus relatively soft layer, also a relatively soft, metallic layer of a metal alloy material, a third, relatively hard graded metal-ceramic layer and a fourth relatively hard, ceramic layer.
  • no method has been known from the prior art by means of which wear protection coatings designed as multi-layer coatings can be effectively removed without the risk of damage to the base material of the gas turbine component.
  • the present invention is based on the problem to provide a novel method for stripping a gas turbine component.
  • the component is positioned in a bath of an alkaline electrolyte to remove the multilayer or multi-layer wear protection coating, wherein the component positioned in the electrolyte is stripped at a current density between 1 A / dm 2 and 20 A / dm 2 .
  • the method according to the invention for stripping a component has the advantage that multi-layer coatings can be removed without residue from the surface of the component to be stripped, without the risk that the base material of the component to be stripped is attacked and thus damaged.
  • titanium-base alloys and nickel-based alloys are not attacked in the stripping according to the invention.
  • Another advantage of the method according to the invention is that components in a single bath can be stripped of the alkaline electrolyte. In the method according to the invention for stripping a component, it is therefore not necessary to provide several different baths.
  • the component positioned in the electrolyte is anodically processed at room temperature.
  • the bath comprises a surfactant in addition to the alkaline electrolyte for reducing the surface tension or interfacial tension.
  • the electrolyte used is in particular a sodium hydroxide solution or a potassium hydroxide solution.
  • a fluorosurfactant is used as the surfactant in an amount to reduce the surface tension to between 20 dynes and 50 dynes.
  • the inventive method is used for stripping of coated with multilayer wear protection coatings components such.
  • the component to be stripped is arranged in a bath of an alkaline electrolyte.
  • the component positioned in alkaline electrolyte is then stripped by applying an electrical current, wherein a current density between 1 A / dm 2 and 20 A / dm 2 is stripped.
  • the stripping takes place by electrochemical means, the component to be stripped being processed predominantly anodically, that is to say, it is connected predominantly as an anode during stripping.
  • the component to be stripped can be temporarily switched as a cathode to increase the efficiency of stripping at defined time intervals.
  • the EntSchichtung of the positioned in the alkaline electrolyte component takes place with a current density between 1 A / dm 2 and 5 A / dm second
  • the stripping is preferably carried out under room temperature.
  • the alkaline electrolyte used is preferably sodium hydroxide solution or potassium hydroxide solution.
  • a bath which comprises a surfactant in addition to the alkaline electrolyte.
  • the surfactant is preferably a fluorosurfactant.
  • the amount of surfactant is determined in such a way that the surface tension or interfacial tension is reduced to a value between 20 dyn and 50 dyn, in particular to a value between 25 dyn and 35 dyn.
  • the component is to be stripped only on certain surface sections, not to be stripped areas or sections of the component are covered with a wax-containing material or with a waxy material prior to stripping.
  • a wax-containing material or with a waxy material prior to stripping.
  • This can be z. B. be used when a gas turbine blade exclusively in the region of its blade, but not in the region of the blade root, to be stripped.
  • the blade root is then covered with a wax-containing material or a wax-like material before the arrangement of the gas turbine blade in the bath.
  • the inventive method allows effective and gentle removal of multilayer coatings of components.
  • the stripping takes place by electrochemical means, with a single bath of an alkaline electrolyte is sufficient. There is no risk that the base material of the component to be stripped is removed and thus damaged.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)

Abstract

La présente invention concerne un procédé de décapage d'un élément structurel, en particulier d'un élément de turbine à gaz, destiné notamment au retrait complet ou partiel d'un revêtement multicouche de protection contre l'usure qui recouvre la surface de l'élément structurel, le revêtement de protection contre l'usure comprenant au moins une couche céramique relativement dure et au moins une couche métallique relativement souple. Selon l'invention, pour permettre le retrait du revêtement multicouche de protection contre l'usure, l'élément structurel est placé dans un bain d'électrolyte alcalin, l'élément structurel qui se trouve dans l'électrolyte étant décapé avec une densité de courant comprise entre 1 A/dm<SUP>2</SUP> et 20 A/dm<SUP>2</SUP>.
EP08758017A 2007-05-15 2008-05-02 Procédé de décapage d'un élément structurel Withdrawn EP2147134A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007022832A DE102007022832A1 (de) 2007-05-15 2007-05-15 Verfahren zur Entschichtung eines Bauteils
PCT/DE2008/000756 WO2008138301A1 (fr) 2007-05-15 2008-05-02 Procédé de décapage d'un élément structurel

Publications (1)

Publication Number Publication Date
EP2147134A1 true EP2147134A1 (fr) 2010-01-27

Family

ID=39708426

Family Applications (1)

Application Number Title Priority Date Filing Date
EP08758017A Withdrawn EP2147134A1 (fr) 2007-05-15 2008-05-02 Procédé de décapage d'un élément structurel

Country Status (5)

Country Link
US (1) US20100108538A1 (fr)
EP (1) EP2147134A1 (fr)
CA (1) CA2679308A1 (fr)
DE (1) DE102007022832A1 (fr)
WO (1) WO2008138301A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010010770A1 (de) * 2010-03-09 2011-09-15 Lufthansa Technik Ag Verfahren zum elektrochemischen Entschichten von Gasturbinenbauteilen
DE102010010771A1 (de) * 2010-03-09 2011-09-15 Lufthansa Technik Ag Verfahren zum elektrochemischen Entschichten von Gasturbinenbauteilen
US20200055615A1 (en) * 2017-02-01 2020-02-20 Aeromet Technology Solutions, Llc Method and apparatus for removing coatings

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4435840C1 (de) * 1994-10-07 1996-03-21 Bayer Ag Verwendung von alkylsubstituierten Perfluoralkylsulfonamiden als Sprühnebelinhibitoren für basische Elektrolysebäder
US6132520A (en) * 1998-07-30 2000-10-17 Howmet Research Corporation Removal of thermal barrier coatings
US6428683B1 (en) * 2000-12-15 2002-08-06 United Technologies Corporation Feedback controlled airfoil stripping system with integrated water management and acid recycling system
DE10128507B4 (de) * 2001-06-14 2008-07-17 Mtu Aero Engines Gmbh Verwendung einer Vorrichtung zum chemischen oder elektrochemischen Bearbeiten von Bauteilen
US6969457B2 (en) * 2002-10-21 2005-11-29 General Electric Company Method for partially stripping a coating from the surface of a substrate, and related articles and compositions
US7078073B2 (en) * 2003-11-13 2006-07-18 General Electric Company Method for repairing coated components
DE102004001392A1 (de) * 2004-01-09 2005-08-04 Mtu Aero Engines Gmbh Verschleißschutzbeschichtung und Bauteil mit einer Verschleißschutzbeschichtung
US20060137995A1 (en) * 2004-12-29 2006-06-29 Sukanta Ghosh Method for removal of metal from a workpiece
US20060226025A1 (en) * 2005-03-16 2006-10-12 Colorado School Of Mines Electrochemical removal of die coatings
DE102005041844A1 (de) * 2005-09-02 2007-03-08 Mtu Aero Engines Gmbh Verfahren zum Beschichten oder Entschichten eines Bauteils
DE102005049249B4 (de) * 2005-10-14 2018-03-29 MTU Aero Engines AG Verfahren zur Entschichtung eines Gasturbinenbauteils

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2008138301A1 *

Also Published As

Publication number Publication date
DE102007022832A1 (de) 2008-11-20
CA2679308A1 (fr) 2008-11-20
US20100108538A1 (en) 2010-05-06
WO2008138301A1 (fr) 2008-11-20

Similar Documents

Publication Publication Date Title
DE60219116T2 (de) Verfahren zur Entfernung von einer Metallverkleidung von einem Turbinenschaufel
DE2722263A1 (de) Verfahren zur erneuernden oberflaechenbehandlung von turbinen-komponenten u.dgl.
CH635018A5 (de) Verfahren zum aufbringen einer oberflaechenschicht durch fusionsschweissen.
EP1934387B1 (fr) Procede pour retirer un revetement present sur un composant de turbine a gaz
WO2017060041A1 (fr) Réparation d&#39;une pièce présentant des fissures et pièce
EP2064025A1 (fr) Procédé de réparation
WO2010051799A2 (fr) Procédé de réparation
EP1730330A1 (fr) Procede et electrode pour enlever un revetement par electrochimie sur des elements de construction
EP3118352B1 (fr) Procede de revetement galvanique d&#39;alliages tial
WO2006042506A1 (fr) Procede de fabrication d&#39;une piece pourvue d&#39;un revetement de protection contre l&#39;usure
DE102010022597A1 (de) Verfahren zum Herstellen einer Schicht mittels Kaltgasspritzen und Verwendung einer solchen Schicht
EP2147134A1 (fr) Procédé de décapage d&#39;un élément structurel
EP3093371B1 (fr) Combinaison de blindage d&#39;extremite d&#39;aubes et de couche de protection contre l&#39;erosion et son procede de fabrication
DE102006044416A1 (de) Verfahren zum elektrochemischen Be- oder Entschichten von Bauteilen
EP1743053B1 (fr) Procede de production d&#39;un revetement
DE19536312C1 (de) Verfahren zur Herstellung eines mehrlagig beschichteten Bauteils mit Bohrungen
DE102005041844A1 (de) Verfahren zum Beschichten oder Entschichten eines Bauteils
DE102004049825A1 (de) Verfahren zum Entschichten von Bauteilen
DE102005011011A1 (de) Bauteil, insbesondere Gasturbinenbauteil
DE102007062559A1 (de) Verfahren zur Herstellung und Reparatur eines Bauteils und Bauteil einer Gasturbine
DE10349073A1 (de) Hohlfanschaufel für Flugzeugtriebwerke und Verfahren zu deren Herstellung
WO2011110323A1 (fr) Procédé d&#39;enlèvement de revêtement par voie électrochimique pour éléments structuraux de turbine à gaz
EP3626864B1 (fr) Procédé d&#39;élimination d&#39;un revêtement en matière dure
DE3627779A1 (de) Erneuertes turbinenbauteil
EP2545210B1 (fr) Procédé d&#39;enlèvement de revêtement par voie électrochimique pour éléments structuraux de turbine à gaz

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20091112

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA MK RS

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20130628

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20131109