EP0194392A1 - Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen - Google Patents

Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen Download PDF

Info

Publication number
EP0194392A1
EP0194392A1 EP85400478A EP85400478A EP0194392A1 EP 0194392 A1 EP0194392 A1 EP 0194392A1 EP 85400478 A EP85400478 A EP 85400478A EP 85400478 A EP85400478 A EP 85400478A EP 0194392 A1 EP0194392 A1 EP 0194392A1
Authority
EP
European Patent Office
Prior art keywords
nickel
article
tantalum
tungsten
chromium
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
EP85400478A
Other languages
English (en)
French (fr)
Other versions
EP0194392B1 (de
Inventor
Melvin Robert Jackson
Swe-Wong Yang
Michael Francis Xavier Gigliotti, Jr.
John Ruel Rairden Iii
Mark Louis Prugar
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.)
OFFERTA DI LICENZA AL PUBBLICO
Original Assignee
General Electric Co
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 General Electric Co filed Critical General Electric Co
Priority to EP19850400478 priority Critical patent/EP0194392B1/de
Priority to DE8585400478T priority patent/DE3572512D1/de
Publication of EP0194392A1 publication Critical patent/EP0194392A1/de
Application granted granted Critical
Publication of EP0194392B1 publication Critical patent/EP0194392B1/de
Priority to SG63390A priority patent/SG63390G/en
Expired legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C30/00—Coating with metallic material characterised only by the composition of the metallic material, i.e. not characterised by the coating process
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C22C19/051—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W
    • C22C19/056—Alloys based on nickel or cobalt based on nickel with chromium and Mo or W with the maximum Cr content being at least 10% but less than 20%

Definitions

  • This invention pertains generally to nickel-base superalloys useful in the manufacture of hot-section components of aircraft gas turbine engines, e.g., vanes and rotating blades, and more particularly to compatible coatings especially useful for the enhancement of the environmental resistance of such hot-section components made from advanced nickel-base superalloys and nickel-base eutectic superalloys.
  • Advanced nickel-base superalloys such as the monocarbide reinforced nickel-base eutectic superalloys of the type described, for example, in U.S. Patent 4,292,076 to Gigliotti, Jr. et al., which is incorporated herein by reference, are designed for use as unidirectionally solidified anisotropic metallic bodies, primarily in the form of vanes and rotating blades in aircraft gas turbine engines.
  • Patent 4,292,076 when directionally solidified (DS'd) under stringent conditions to achieve planar front solidification (PFS), result in a eutectic composite microstructure consisting of strong, reinforcing metallic carbide (MC) fibers in a 7/Y' nickel-base superalloy matrix. Because highly aligned microstructures are formed during planar front solidification, the superalloys of U.S. Patent 4,292,076 offer potential structural stability and property retention to a greater fraction of their solidification temperatures than do other materials.
  • DS'd directionally solidified
  • PFS planar front solidification
  • the eutectic superalloys have been identified as the next generation of blade alloys beyond directionally solidified and single crystal superalloys. In order to take full temperature advantage of those superalloys, however, coatings are required to provide environmental protection at the high intended use temperatures.
  • the coatings must be tightly bonded, i.e., metallurgically bonded, to the substrate and ideally must not degrade either the mechanical properties of the substrate (e.g., ductility, stress rupture strength and resistance to thermal fatigue) or the chemical properties of the substrate (e.g., oxidation resistance and hot corrosion resistance).
  • the mechanical properties of the substrate e.g., ductility, stress rupture strength and resistance to thermal fatigue
  • the chemical properties of the substrate e.g., oxidation resistance and hot corrosion resistance
  • Examples of adverse effects to eutectic superalloys which have resulted from incompatible coatings are fiber denudation near the coating/substrate interface due to outward diffusion of carbon from the fiber into the coating and the formation of brittle precipitates in the substrate due to interdiffusion between the coating and the substrate.
  • nickel-base superalloy which is mechanically and chemically compatible with advanced nickel-base superalloys and nickel-base eutectic superalloys, and which possesses excellent resistance to high temperature oxidation.
  • the alloy of the invention is, therefore, particularly useful as a protective environmental coating for the external surfaces of hot stage aircraft gas turbine engine components, e.g., rotating blades and stationary vanes, made from advanced nickel-base superalloys and nickel-base eutectic superalloys.
  • the superalloy of the invention consists essentially of about, by weight, 1 to 10% cobalt, 6 to 12% chromium, 5 to 8% aluminum, 1 to 10% tantalum, 1 to 10% tungsten, 0 to 3% rhenium, 0 to 2% molybdenum, 0.1 to 2% hafnium, 0.005 to 0.1% boron, 0.005 to 0.25% carbon, the balance being nickel and incidental impurities.
  • novel superalloy will be applied most frequently as a protective environmental coating to comprise at least a portion of the outer surface of gas turbine engine components and articles
  • novel alloy of this invention is useful as a thicker, built-up deposit applied to selected regions of substrates, such as aircraft gas turbine engine components, for repair purposes, or as the tip portion of rotating blades.
  • substrates such as aircraft gas turbine engine components
  • Such applications contemplate composite articles of manufacture : having as a substrate an article, such as a gas turbine. engine airfoil, made of a nickel-base superalloy or .
  • nickel-base eutectic superalloy and one or more thick, built-up regions contiguous with, i.e., joined to and forming an integral part of, the substrate wherein the one or more regions comprise at least a portion of the outer surface of the composite article and are of the above-described novel superalloy composition.
  • the present invention relates to a nickel-base superalloy which is mechanically and chemically compatible with advanced nickel-base superalloys and nickel-base eutectic superalloys and which possesses excellent resistance to high temperature oxidation.
  • the superalloy of the invention consists essentially of cobalt, chromium, aluminum, tantalum, tungsten, rhenium, mo bdenum, hafnium, boron and carbon in the percentages by weight) set forth in Table I below, the balance vide nickel and incidental impurities.
  • the present alloy is particularly useful as a protective environmental coating, of between about 0.002 and 0.1 inches in thickness, for the external surfaces of solid and hollow, fluid-cooled gas turbine engine components, e.g., rotating blades and stationary vanes, operating in the hot stage sections of such turbines and made from advanced nickel-base superalloys and nickel-' se eutectic superalloys. While it is contemplate that the novel alloy herein described will most frequenaly be applied as protective environmental coatings to provide at least a portion of the outer surface of gas turbine engine components and articles, it has also been found that the superalloy of the invention is also useful as one or more thicker, built-up deposits applied to selected regions of such articles or component-like substrates.
  • the utilization of plasma spray techniques to deposit the alloy of the invention is preferred. Most preferred is the technique, sometimes referred to as low pressure plasma deposition (LPPD), described in U.S. Patent 3,839,618 - Muehlberger, which patent is incorporated herein by reference. Alloys in accordance with the present invention produce very dense coatings or deposits after plasma spraying and especially after plasma spraying by the above-mentioned LPPD process whereby as-deposited densities of 95% and greater are readily obtained.
  • LPPD low pressure plasma deposition
  • 6 0. series of coatings, hereinafter referred to as the "6 " or 6M-type coatings by way of designation, were produced by low pressure plasma deposition of an alloy of the invention, i.e., one consisting essentially of, nominally by weight within normal melting tolerances, 4% Co, 8.5% Cr, 6% Al, 5% Ta, 4.5% W, 1.5% Re, 1.5% Mo, 0.9% Hf, 0.01% B, and 0.09% C, the balance nickel and incidental impurities, onto flat plate-like substrates and pin-like substrates for environmental testing.
  • an alloy of the invention i.e., one consisting essentially of, nominally by weight within normal melting tolerances, 4% Co, 8.5% Cr, 6% Al, 5% Ta, 4.5% W, 1.5% Re, 1.5% Mo, 0.9% Hf, 0.01% B, and 0.09% C, the balance nickel and incidental impurities, onto flat plate-like substrates and pin-like substrates for environmental testing.
  • NiCoCrAlY Ni-23Co-18Cr-12.5Al-0.3Y
  • All coatings of the NiCoCrAlY type were deposited by a commercial vendor using the physical vapor deposition (PVD) process described in the aforementioned 3,928,026. patent.
  • the B-type substrates Prior to coating deposition, the B-type substrates were solution treated at 2325° F for two hours and the N-type substrates were solution treated at 2310° F for two hours irrespective of the coating to be applied.
  • the process of applying the NiCoCrAlY type coatings has been described above.
  • the 6M coatings were applied by the above-described LPPD plasma spray process.
  • a commercially available standard internal feed plasma spray gun and the process parameters of Table II were used.
  • the N-type substrates a commercially available standard external feed plasma spray gun and the process parameters of fable III were used.
  • the structure of the B-type substrate is one of an aligned eutectic (TaC) fibrous reinforcing phase in a ⁇ / ⁇ ' matrix while the structure of the N-type substrate is one of y' precipitates in ay matrix.
  • TaC aligned eutectic
  • Table IV presents the results of cyclic oxidation tests on pin-like specimens conducted under the conditions shown in the table using a natural gas flame at the velocities shown in the table.
  • the specimens were rotated for uniform exposure and cycled out of the flame 1 or 6 times per hour to cool the specimens to about 800° F. Failure is defined as penetration of the coating to the extent that (substrate) oxidation begins to occur.
  • Hot corrosion testing was conducted at 1700° F using a JP-5 fuel-fired flame with 5 ppm salt added to the combustion products. The specimens were rotated for uniform exposure and cycled out of the flame once every hour.
  • the alloy of the invention as a coating provides good protection to both substrates, and particularly to the B-type substrate.
  • the oxidation resistance provided by the alloy of the invention is somewhat greater than would be expected based on a study of its overall composition.
  • the alloy of the invention as a coating provides acceptable environmental protection against hot corrosion, i.e., greater than 540 hours life on B-type substrates (test terminated prior to failure) and 1000 hours on N-type substrates.
  • the coated specimens were evaluated metallographically to determine the extent of interaction between the coatings and the substrate.
  • the results are given in Table V which lists the extent, if any, of the denuded and platelet formation zones, the sum of which comprise the interaction zone, following exposure in the oxidation tests at the temperatures and for the times shown.
  • Platelets such as those shown in Figures 3 and 7 for NiCoCrAlY on the B and N-type substrates, respectively, are a result of the interdiffusion of elements between the coating and the substrate, i.e., a chemical incompatibility between the coating and the substrate. The platelets are undesirable due to their needle-like morphology and brittleness.
  • the denuded zone also shown in Figures 3 and 7, is a zone which has been depleted of ⁇ ' due to - the diffusion of elements from the substrate to the coating, leaving a weakened, primarily ⁇ matrix.
  • the alloy of the invention also possesses high temperature strength superior to NiCoCrAlY. Elevated temperature tensile tests on very thick (-1/2 inch) deposits of the NiCoCrAlY and 6M-type alloys showed that at 1800° F the ultimate tensile strength (UTS) of the materials was about 7 and 30 ksi, respectively, while at 2000° F the UTS of the materials was about 3 and 7, respectively. The higher strength of the 6M-type alloy is expected to result in greatly improved resistance to thermal/mechanical fatigue cracking.
  • the difference in the coefficient of thermal expansion (a) between the alloy of the invention and nickel-base superalloy substrates is less than that between NiCoCrAlY and the same superalloy substrates.
  • the smaller difference in a reduces the stresses imposed on a coating alloy in service, and thereby reduces the propensity for coating spallation and thermal fatigue cracking.
  • the low propensity of the alloy of the invention to form interaction zones, and particularly its low propensity to form platelets, plus its higher strength and thermal expansion compatibility with superalloy substrates makes the alloy of the invention a coating which is truly chemically and physically compatible with nickel-base superalloy substrates, in addition to providing the environmental resistance required in severe high pressure, high temperature turbine environments.
  • the novel alloys of this invention are useful as thicker, built-up deposits applied to selected regions of aircraft gas turbine engine components, such as the tip portions of rotating blades or stationary vanes, or for purposes of repairing nicked or damaged regions as typically occur on such components as airfoils.
  • the alloys of the invention are more in the nature of a superalloy from which components are made, e.g., structural or weight-carrying alloys, and less in the nature of coatings.
  • the changes required in the plasma spraying process to effect the build-up of thicker deposits, as opposed to thin coatings, are well within the knowledge and expertise of those ordinarily skilled in the plasma spraying arts.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
EP19850400478 1985-03-13 1985-03-13 Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen Expired EP0194392B1 (de)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP19850400478 EP0194392B1 (de) 1985-03-13 1985-03-13 Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen
DE8585400478T DE3572512D1 (en) 1985-03-13 1985-03-13 Nickel-base superalloys especially useful as compatible protective environmental coatings for advanced superalloys
SG63390A SG63390G (en) 1985-03-13 1990-08-01 Nickel-base superalloys especially useful as compatible protective environmental coatings for advanced superalloys

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19850400478 EP0194392B1 (de) 1985-03-13 1985-03-13 Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen

Publications (2)

Publication Number Publication Date
EP0194392A1 true EP0194392A1 (de) 1986-09-17
EP0194392B1 EP0194392B1 (de) 1989-08-23

Family

ID=8194507

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19850400478 Expired EP0194392B1 (de) 1985-03-13 1985-03-13 Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen

Country Status (3)

Country Link
EP (1) EP0194392B1 (de)
DE (1) DE3572512D1 (de)
SG (1) SG63390G (de)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5273712A (en) * 1989-08-10 1993-12-28 Siemens Aktiengesellschaft Highly corrosion and/or oxidation-resistant protective coating containing rhenium
US5401307A (en) * 1990-08-10 1995-03-28 Siemens Aktiengesellschaft High temperature-resistant corrosion protection coating on a component, in particular a gas turbine component
US5582635A (en) * 1990-08-10 1996-12-10 Siemens Aktiengesellschaft High temperature-resistant corrosion protection coating for a component in particular a gas turbine component
DE3719902A1 (de) * 1986-01-02 1997-05-22 United Technologies Corp Superlegierungs-Zusammensetzung und Einkristall-Superlegierungs-Gegenstand auf Nickelbasis mit säulenartiger Kornform
US6924046B2 (en) 2001-10-24 2005-08-02 Siemens Aktiengesellschaft Rhenium-containing protective layer for protecting a component against corrosion and oxidation at high temperatures
EP1837412A3 (de) * 2006-03-24 2011-03-16 United Technologies Corporation Beschichtung geeignet zur Verwendung als Bindeschicht in einem wärmedämmenden Beschichtungssystem
US8025984B2 (en) 2003-10-17 2011-09-27 Siemens Aktiengesellschaft Protective layer for protecting a component against corrosion and oxidation at high temperatures, and component
JP2018515690A (ja) * 2015-04-01 2018-06-14 オックスフォード ユニバーシティ イノベーション リミテッドＯｘｆｏｒｄ Ｕｎｉｖｅｒｓｉｔｙ Ｉｎｎｏｖａｔｉｏｎ Ｌｉｍｉｔｅｄ ニッケル基合金

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1780294A1 (de) 2005-10-25 2007-05-02 Siemens Aktiengesellschaft Legierung, Schutzschicht zum Schutz eines Bauteils gegen Korrosion und Oxidation bei hohen Temperaturen und Bauteil

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3896547A (en) * 1974-05-02 1975-07-29 Sterndent Corp Prosthetic article and method for manufacture
FR2457907A1 (fr) * 1979-05-29 1980-12-26 Howmet Turbine Components Composition de revetement pour la protection contre l'oxydation a haute temperature des super-alliages et composants en super-alliages ainsi revetus
FR2503189A1 (fr) * 1981-03-31 1982-10-08 Howmet Turbine Components Composition de revetement pour superalliages resistant a l'oxydation a haute temperature et superalliages revetus de cette composition
US4459160A (en) * 1980-03-13 1984-07-10 Rolls-Royce Limited Single crystal castings

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3896547A (en) * 1974-05-02 1975-07-29 Sterndent Corp Prosthetic article and method for manufacture
FR2457907A1 (fr) * 1979-05-29 1980-12-26 Howmet Turbine Components Composition de revetement pour la protection contre l'oxydation a haute temperature des super-alliages et composants en super-alliages ainsi revetus
US4459160A (en) * 1980-03-13 1984-07-10 Rolls-Royce Limited Single crystal castings
FR2503189A1 (fr) * 1981-03-31 1982-10-08 Howmet Turbine Components Composition de revetement pour superalliages resistant a l'oxydation a haute temperature et superalliages revetus de cette composition

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
THIN SOLID FILMS, vol. 84, 6th-10th April 1982, pages 49-58, Metallurgical and protective coatings, Conference on Metallurgical Coatings, San Francisco, CA, US, Elsevier, Netherlands; F.J. PENNISI et al.: "Improved plasma-sprayed Ni-Co-Cr-Al-Y and Co-Cr-Al-Y coatings for aircraft gas turbine applications" *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3719902A1 (de) * 1986-01-02 1997-05-22 United Technologies Corp Superlegierungs-Zusammensetzung und Einkristall-Superlegierungs-Gegenstand auf Nickelbasis mit säulenartiger Kornform
DE3719902C2 (de) * 1986-01-02 2001-11-08 United Technologies Corp Superlegierungs-Gegenstand auf Nickelbasis mit säulenartiger Kristall-Kornform
US5273712A (en) * 1989-08-10 1993-12-28 Siemens Aktiengesellschaft Highly corrosion and/or oxidation-resistant protective coating containing rhenium
US5401307A (en) * 1990-08-10 1995-03-28 Siemens Aktiengesellschaft High temperature-resistant corrosion protection coating on a component, in particular a gas turbine component
US5582635A (en) * 1990-08-10 1996-12-10 Siemens Aktiengesellschaft High temperature-resistant corrosion protection coating for a component in particular a gas turbine component
US5599385A (en) * 1990-08-10 1997-02-04 Siemens Aktiengesellschaft High temperature-resistant corrosion protection coating for a component, in particular a gas turbine component
US6924046B2 (en) 2001-10-24 2005-08-02 Siemens Aktiengesellschaft Rhenium-containing protective layer for protecting a component against corrosion and oxidation at high temperatures
US8025984B2 (en) 2003-10-17 2011-09-27 Siemens Aktiengesellschaft Protective layer for protecting a component against corrosion and oxidation at high temperatures, and component
EP1837412A3 (de) * 2006-03-24 2011-03-16 United Technologies Corporation Beschichtung geeignet zur Verwendung als Bindeschicht in einem wärmedämmenden Beschichtungssystem
JP2018515690A (ja) * 2015-04-01 2018-06-14 オックスフォード ユニバーシティ イノベーション リミテッドＯｘｆｏｒｄ Ｕｎｉｖｅｒｓｉｔｙ Ｉｎｎｏｖａｔｉｏｎ Ｌｉｍｉｔｅｄ ニッケル基合金

Also Published As

Publication number Publication date
SG63390G (en) 1990-09-07
DE3572512D1 (en) 1989-09-28
EP0194392B1 (de) 1989-08-23

Similar Documents

Publication Publication Date Title
US5035958A (en) Nickel-base superalloys especially useful as compatible protective environmental coatings for advanced superaloys
US5043138A (en) Yttrium and yttrium-silicon bearing nickel-base superalloys especially useful as compatible coatings for advanced superalloys
EP0194391B1 (de) Yttrium und Yttrium-Silizium enthaltende Nickel-Basis-Superlegierungen die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen
CA1045421A (en) High temperature nicocraly coatings
US4005989A (en) Coated superalloy article
US4743514A (en) Oxidation resistant protective coating system for gas turbine components, and process for preparation of coated components
US4447503A (en) Superalloy coating composition with high temperature oxidation resistance
US4789441A (en) Metallic protective coatings and method of making
US4339509A (en) Superalloy coating composition with oxidation and/or sulfidation resistance
US4313760A (en) Superalloy coating composition
US5238752A (en) Thermal barrier coating system with intermetallic overlay bond coat
US5498484A (en) Thermal barrier coating system with hardenable bond coat
US6153313A (en) Nickel aluminide coating and coating systems formed therewith
US4880614A (en) Ceramic thermal barrier coating with alumina interlayer
US6291084B1 (en) Nickel aluminide coating and coating systems formed therewith
US5015502A (en) Ceramic thermal barrier coating with alumina interlayer
US6964791B2 (en) High-temperature articles and method for making
US5599385A (en) High temperature-resistant corrosion protection coating for a component, in particular a gas turbine component
US3869779A (en) Duplex aluminized coatings
US3849865A (en) Method of protecting the surface of a substrate
US4615864A (en) Superalloy coating composition with oxidation and/or sulfidation resistance
JPS6354794B2 (de)
US4485148A (en) Chromium boron surfaced nickel-iron base alloys
EP0194392B1 (de) Nickel-Basis-Superlegierungen, die insbesondere geeignet sind als kompatible Beschichtungen für moderne Superlegierungen
US6974637B2 (en) Ni-base superalloy having a thermal barrier coating system

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

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT NL SE

17P Request for examination filed

Effective date: 19870304

17Q First examination report despatched

Effective date: 19880303

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT NL SE

ET Fr: translation filed
REF Corresponds to:

Ref document number: 3572512

Country of ref document: DE

Date of ref document: 19890928

ITF It: translation for a ep patent filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19921224

Year of fee payment: 9

ITTA It: last paid annual fee
ITPR It: changes in ownership of a european patent

Owner name: OFFERTA DI LICENZA AL PUBBLICO

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19940210

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19940215

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19940224

Year of fee payment: 10

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19940313

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19940331

Year of fee payment: 10

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19940313

EAL Se: european patent in force in sweden

Ref document number: 85400478.5

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19950314

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19951001

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19951130

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee

Effective date: 19951001

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19951201

EUG Se: european patent has lapsed

Ref document number: 85400478.5

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST