EP0493280A1 - Kupferrohre mit verbesserter Korrosionsbeständigkeit sowie Verfahren zu ihrer Herstellung - Google Patents

Kupferrohre mit verbesserter Korrosionsbeständigkeit sowie Verfahren zu ihrer Herstellung Download PDF

Info

Publication number
EP0493280A1
EP0493280A1 EP91420463A EP91420463A EP0493280A1 EP 0493280 A1 EP0493280 A1 EP 0493280A1 EP 91420463 A EP91420463 A EP 91420463A EP 91420463 A EP91420463 A EP 91420463A EP 0493280 A1 EP0493280 A1 EP 0493280A1
Authority
EP
European Patent Office
Prior art keywords
tube
treatment according
tubes
liquid mixture
copper
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
EP91420463A
Other languages
English (en)
French (fr)
Other versions
EP0493280B1 (de
Inventor
Pascal Leterrible
Marcel Negrerie
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.)
Trefimetaux SAS
Original Assignee
Trefimetaux SAS
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 Trefimetaux SAS filed Critical Trefimetaux SAS
Publication of EP0493280A1 publication Critical patent/EP0493280A1/de
Application granted granted Critical
Publication of EP0493280B1 publication Critical patent/EP0493280B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
    • F28F19/02—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/1204—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material inorganic material, e.g. non-oxide and non-metallic such as sulfides, nitrides based compounds
    • C23C18/1208—Oxides, e.g. ceramics
    • C23C18/1216—Metal oxides
    • 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
    • C23C18/00—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
    • C23C18/02—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition
    • C23C18/12—Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating by thermal decomposition characterised by the deposition of inorganic material other than metallic material
    • C23C18/125—Process of deposition of the inorganic material
    • C23C18/1287—Process of deposition of the inorganic material with flow inducing means, e.g. ultrasonic

Definitions

  • the invention relates to the field of copper tubes used for sanitary, for domestic or industrial heat exchangers and more generally the fields of use of copper tubes, or copper alloys, which involve localized heating of said tubes either during their mounting, possibly during their final use.
  • the tube heating conditions are generally not good under control. Indeed, the instantaneous temperature is assessed by visual examination of the color of the tube, which itself depends very much on the ambient light.
  • abnormally exaggerated heating conditions can occur, for example to make up for a poorly made weld or to connect tubes of very different diameter. In all cases, this results in an aggravation of the risk of corrosion by "pitting", or pitting of the metal which can lead to a perforation of the metal, when the tube is brought into contact with water, even moderately aggressive for copper. Numerous tests have shown the relationship between the heating conditions and the density of pits which appear later on contact with water.
  • a person skilled in the art knows a certain number of methods intended to limit the formation of discontinuous films inside the tubes, films which are harmful to corrosion resistance, in particular in the form of pitting.
  • One method consists in circulating in the tube which has undergone localized heating at high temperature, a nitrogen atmosphere or a mist of water and alcohol,
  • Another process known as "Flux Gas”
  • Flured Gas consists in incorporating a reducing product directly into the fuel gas of the torch.
  • the subject of the invention is a method of treating the interior, and also optionally the exterior, of copper tubes during their industrial manufacture so as to provide the user with a tube of improved resistance to corrosion without this user does not have to take any special precautions for use, in particular during localized temporary heating necessary for the shaping of the tubes or their mounting, nor to carry out specific treatments on these tubes after having carried out said temporary heating.
  • the tubes obtained according to the invention make it possible to improve the life of the tubes without introducing constraints for the user client, which is of great practical interest.
  • the treatment of copper or copper alloy tubes intended to improve their resistance to corrosion resulting from temporary heating of said tubes is characterized in that a thin hydrophobic layer comprising a boron compound, inert with respect to copper and forming boric anhydride B2O3 during said heating, is formed on the surface of said tube temporary.
  • a boron compound inert with respect to copper can, according to the invention, be chosen from non-ionic mineral boron derivatives, typically B2O3, organic derivatives of boric acid, precursors of B2O3, leading to the formation of B2O3 by heating, in particular under the conditions of said temporary heating.
  • non-ionic mineral boron derivatives typically B2O3, organic derivatives of boric acid, precursors of B2O3, leading to the formation of B2O3 by heating, in particular under the conditions of said temporary heating.
  • the Applicant has observed that the risks of corrosion are linked to the presence of discontinuous films, either of carbon or of copper oxides obtained during said localized heating, the nature or the chemical composition of the latter (in particular , the CuO content) having a great influence on the thickness of the film, its morphology and finally its greater or lesser adhesion.
  • B2O3 had to be present, in a continuous thin layer on the internal surface of the tube during the temporary heating of the tube (formation of a liquid layer of molten B2O3), with a layer thickness advantageously between 50 and 5000 ⁇ , and preferably between 100 and 1000 ⁇ .
  • B2O active is the active substance which improves the corrosion resistance of the tubes after temporary heating.
  • B2O que had to be both very divided and very finely and evenly distributed on the surface of the tube, and for that, formed from of B2O3 or a precursor of B2O3 in the very state divided (in solution or in the form of a fine dispersion), and that B2O3 or its precursor forms a thin hydrophobic layer on the surface of the tube to be protected, such a layer being obtained by application, on the tube surface to be treated, d '' a hydrophobic liquid mixture comprising B2O3 or its precursor and an easily removable organic solvent.
  • easily removable solvent is meant a solvent which can be removed between room temperature and 200 ° C.
  • the precursors of B2O3 according to the invention are preferably organic compounds of boric acid, but can also be mineral compounds of boron inert with respect to copper.
  • boric esters of formula B (OR) 3 or, B (OR) 2OH, or B (OH) 2OR, with the radical R representing an aliphatic chain having from 1 to 24 carbon atoms, were particularly suitable.
  • boric esters of formula B (OR) 3 or, B (OR) 2OH, or B (OH) 2OR are generally obtained by total or partial reaction of alcohol ROH with boron trichloride BCl3 or boric anhydride B2O3 or l 'boric acid H3BO3.
  • boric esters in which the radical R representing an aliphatic chain having from 1 to 22 carbon atoms substituted by an amine group (-NR′R ⁇ , R′ and R ⁇ representing H or an aliphatic chain unless 5 carbon atoms) and / or nitro (-NO2) and / or halogen.
  • the boric esters according to the invention are chosen according to different criteria such as their availability or the possibility of preparing them easily, their cost, their volatility and solubility in organic solvents, esters soluble in organic solvents being preferred . It is also possible according to the invention to use mixtures of these boric esters.
  • boric esters preferably used are those which are soluble in volatile organic solvents or which are easily removable.
  • boric esters are used which are soluble in organic solvents, in which the radical R represents an aliphatic chain having from 2 to 5 carbon atoms. It is important to note the non-toxicity of these boric esters.
  • a fine dispersion of B2O3 or of B2O3 precursor in the volatile solvent using known means of dispersion or grinding and using additives with dispersing action in an organic solvent medium to obtain a liquid mixture consisting of a stable dispersion of fine particles, and / or film-forming additives which make it possible to obtain, after elimination of the solvents, a thin hydrophobic layer having no discontinuity, such an additive coating the fine particles, in particular in the case of a dispersion of B2O3 in a solvent medium.
  • said liquid mixtures according to the invention comprise at least one volatile solvent and B2O3 or a B2O3 precursor with a content of borated derivative of between 1 and 40% and preferably between 10 and 30% by weight.
  • the surface of said tubes is brought into contact with said hydrophobic liquid mixture, possibly using a carrier medium for said hydrophobic liquid mixture, so as to deposit and form a thin layer adhering to said surface, then the surface of the tube is removed. excess hydrophobic liquid mixture not adhering to the surface of the tube.
  • the deposition of thin layer can be carried out according to different methods of the process depending in particular on the nature of said carrier medium.
  • a gas is used as the carrier medium: said hydrophobic liquid mixture is nebulized under form of gaseous suspension, aerosol type, which is circulated inside the tubes, with deposition on the walls.
  • a fibrous pad, impregnated with said hydrophobic liquid mixture is used as the medium carrying said liquid mixture, which is circulated inside the tube and from one end to the other of the tube, thanks to means for relative displacement of the tampon with respect to the tube, which may be a compressed gas, preferably compressed air.
  • said medium carrying said liquid mixture is the drawing lubricant used at the last drawing pass of the tube.
  • a boric ester miscible with the drawing lubricant is preferably chosen as the liquid mixture.
  • a pad loaded with lubricant and boric ester soluble in the lubricant is circulated inside the tube and from one end to the other of the tube, by means of a means of relative displacement of the buffer with respect to the tube, so as to simultaneously provide lubrication of the tube and the formation of a thin hydrophobic layer comprising a B2O3 precursor.
  • a fibrous buffer is used as a medium carrying borated derivative and possibly lubricant (last stretch pass)
  • a device comprising a mandrel metallic iron or iron alloy inside the tube to which is fixed the fibrous pad (s), and a fixed electromagnet outside the tube ensuring the immobility of the metal mandrel by its electromagnetic field, thanks electromagnetic forces exerted on the mandrel.
  • the method according to the invention may also include heating the tube during or after the formation of said hydrophobic thin layer.
  • this heating can facilitate the formation of a continuous layer of boron derivative, but it can also be used to remove the solvents or to reduce the organic matter content of the layer deposited on the interior surface of the tube by scanning with an oxidizing gas stream (formation of B2O3 from boric ester) during all or part of the heating.
  • this heating can consist of static or dynamic heating at a temperature between 150 and 950 ° C.
  • dynamic heating is used, for example an induction heating which allows heating of tubes in the process, with localized heating on a portion of tube for a time typically of a few seconds.
  • the presence on the surface of the borated derivative and preferably of organic borate causes during dynamic heating the formation either of a film of B2O3 (heating at low temperature) or of a continuous film of Cu2O (heating at high temperature), which in all cases provides better protection against corrosion of the copper tube.
  • the advantage of this process is to obtain a more adherent oxide than that obtained in a pass-through oven, especially in the case of large diameter tubes.
  • tests 1 to 3 a professional plumber, on the treated tubes (tests 1 to 3) and on the untreated tubes (control tubes) was made to solder at high temperature with a butane torch, under the same conditions, in using usual copper fittings and CuP7% brazing without using solid flux and without water quenching after heating.
  • the brazed tubes After opening the brazed tubes, it appears, on the inner surface, several zones having a surface variable in appearance (color, continuity and thickness of the film), the CuO content of the film, which corresponds to different heating zones. .
  • zone A 750 ° C
  • zone B located 2 cm from the center
  • zone C located 5 cm from the center
  • zone D located 7 cm from the center
  • Zone A is black and flaking for the control test:
  • FIG. 2 reproduces a photograph of zone A of the control test which illustrates the flaking of the inner film (large CuO "plates", 100 to 150 ⁇ m , between which the metal is bare, unprotected).
  • Zone A is red (absence of CuO) and not flaking for test 2 according to the invention:
  • FIG. 4 reproduces a photograph of zone A of test 2 which shows the presence of a continuous film made up of cells contiguous, adherent to the underlying metal and of small dimensions, of the order of 5-15 ⁇ m.
  • test 4 The Applicant has carried out a test (test 4) by applying the method described in document SU 1077 950 A. It first noted that the electrolytic deposition process described in this document is not applicable on an industrial scale to protect the interior of very long copper tubes (problem of the electrodes inside the tube / necessity of a high current density taking into account the surface of the tube / expensive process). However, it carried out a comparative test on a copper plate (lubricated like a tube) according to the data of SU 1077 950 A (test 4) and according to the invention (test 5 which takes up the conditions of test 2: use of '' a solution of amyl borate at 10% by weight in Dilutin).
  • FIGS. 6 to 8 which clearly show the advantage brought by the invention (FIG. 6), either with respect to the untreated tube (control test in FIG. 8) or with respect to the tube treated according to SU 1077950-A (FIG. 7): the tube treated according to the invention is the only one to have a continuous Cu2O surface free of CuO, which gives this tube remarkable resistance to pitting corrosion.
  • the tubes treated according to the invention can be stored for several months before being used, for example brazed, without there being any loss of effect of the borated derivative deposited on the surface of the tube. , which may be due to the hydrophobic nature of the thin layer deposited.
  • the Applicant has obtained a marked improvement in the corrosion resistance after temporary heating of copper or copper alloys treated according to the invention, having, on all or part of their surface, a thin layer comprising a boron derivative according to the invention.
  • This improvement is particularly advantageous in the case of temporary and localized heating required by strong brazing or hot bending operations, operations which, as already mentioned, are often carried out on construction sites in more or less conditions severe, resulting in significant pitting corrosion in use, which may however vary with the severity of the soldering or bending conditions.
  • the significant progress made possible by the invention makes it possible to obtain installations, based on copper tubes, not very sensitive to pitting corrosion, and this practically independently of the operating conditions of usual use of these tubes, in particular on construction sites.
  • the invention also makes it possible to carry out, with little risk of corrosion, works under severe conditions which it would have been inadvisable to carry out with tubes of the prior art.
  • Figure 1 shows in section a tube (1), control tube or tube according to the invention, and a copper fitting (2) assembled by brazing, with a positioning, substantially on scale 1, of the different zones A to D of the tube (1) corresponding to different temperature ranges reached during temporary heating.
  • FIG. 2 is a representation of a photograph obtained with an electron microscope which illustrates the flaking of the interior surface of zone A of the control tube after brazing at high temperature and the formation of large (hatched) plates (1 cm represents 20 ⁇ m), non-contiguous which reveal the underlying metal locally without a protective layer.
  • FIG. 3 illustrates in cross section a puncture at the level of zone A of the control tube, following the corrosion test.
  • the plane (3) represents the starting copper level.
  • Corrosion results in a "mountain” of malachite (4) 150 ⁇ m in height, on a layer formed in particular of oxide crystals (5) forming a vault over a "bowl” (the sting) of 60 ⁇ m deep, the bottom of which contains chlorides.
  • FIG. 4 is a representation of a photograph obtained with an electron microscope which illustrates the state of the internal surface of zone A of the tube of test 2 after brazing at high temperature and the presence of a continuous layer made up of cells adherent to the underlying metal, contiguous and small (1 cm represents 20 ⁇ m), so that the entire metal surface is protected.
  • Figure 5 is a cross-sectional view of the device comprising a metal mandrel (6) to which is bound a felt pad (7) loaded with a solution of borated derivative, kept immobile, relative to the tube (1) which scrolls, thanks to a fixed electromagnet (8) surrounding the tube (1).
  • FIG. 6 to 8 show transverse half-sections of copper tube fittings after temporary heating (brazing with butane torch):
  • FIG. 6 corresponds to the tube obtained according to the invention (test 5). In this case, it is observed that the tube is coated with a continuous film of red Cu2O (10), the B2O3 formed having been removed by vaporization during brazing.
  • Figure 7 corresponds to the tube obtained in test 4 (according to SU 1077-950-A).
  • a Cu2O film red (10) favorable to the protection of the tube, sometimes a black CuO film (11) discontinuous, detrimental to the resistance to pitting corrosion.
  • Figure 8 corresponds to the untreated control tube.
  • most of the heated area is covered with a highly flaking black CuO film (11), with parts that are not adherent to the tube, which is very harmful for resistance to pitting corrosion.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)
  • Chemically Coating (AREA)
  • Chemical Treatment Of Metals (AREA)
  • Pressure Welding/Diffusion-Bonding (AREA)
  • Arc Welding In General (AREA)
EP19910420463 1990-12-26 1991-12-20 Kupferrohre mit verbesserter Korrosionsbeständigkeit sowie Verfahren zu ihrer Herstellung Expired - Lifetime EP0493280B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9016574A FR2671108B1 (fr) 1990-12-26 1990-12-26 Tubes de cuivre a resistance a la corrosion amelioree et procede pour les obtenir.
FR9016574 1990-12-26

Publications (2)

Publication Number Publication Date
EP0493280A1 true EP0493280A1 (de) 1992-07-01
EP0493280B1 EP0493280B1 (de) 1995-12-06

Family

ID=9403911

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19910420463 Expired - Lifetime EP0493280B1 (de) 1990-12-26 1991-12-20 Kupferrohre mit verbesserter Korrosionsbeständigkeit sowie Verfahren zu ihrer Herstellung

Country Status (5)

Country Link
EP (1) EP0493280B1 (de)
JP (1) JPH0776429B2 (de)
DE (1) DE69115237T2 (de)
ES (1) ES2080282T3 (de)
FR (1) FR2671108B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019057609A1 (en) * 2017-09-19 2019-03-28 University Of Warwick METHOD FOR FORMING A COATING WITHIN A INTERNAL PASSAGE

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19533410B4 (de) * 1995-09-09 2005-11-24 Km Europa Metal Ag Verfahren zur Erzeugung einer Schutzschicht an der inneren Oberfläche eines Kupferrohrs sowie Verwendung von Ziehmitteln

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1063564A (en) * 1963-09-16 1967-03-30 United States Borax Chem Method for the protection from corrosion of non-ferrous metals
DE1669159A1 (de) * 1966-12-15 1970-09-03 Foseco Trading Ag Verfahren zum Schuetzen einer Metalloberflaeche

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1077950A1 (ru) * 1982-01-20 1984-03-07 Славянский Филиал Всесоюзного Ордена Ленина Научно-Исследовательского И Проектно-Конструкторского Института Металлургического Машиностроения Способ получени защитного покрыти

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1063564A (en) * 1963-09-16 1967-03-30 United States Borax Chem Method for the protection from corrosion of non-ferrous metals
DE1669159A1 (de) * 1966-12-15 1970-09-03 Foseco Trading Ag Verfahren zum Schuetzen einer Metalloberflaeche

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SOVIET INVENTIONS ILLUSTRATED Section Ch, Week 8443, 5 Décembre 1984 Derwent Publications Ltd., London, GB; Class M, AN 84-268821 & SU-A-1 077 950 (SLAVY METAL ENG RES) 7 Mars 1984 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019057609A1 (en) * 2017-09-19 2019-03-28 University Of Warwick METHOD FOR FORMING A COATING WITHIN A INTERNAL PASSAGE

Also Published As

Publication number Publication date
ES2080282T3 (es) 1996-02-01
JPH04301081A (ja) 1992-10-23
FR2671108B1 (fr) 1994-03-04
EP0493280B1 (de) 1995-12-06
DE69115237D1 (de) 1996-01-18
DE69115237T2 (de) 1996-05-15
FR2671108A1 (fr) 1992-07-03
JPH0776429B2 (ja) 1995-08-16

Similar Documents

Publication Publication Date Title
FR2731232A1 (fr) Procede de traitement de surfaces ferreuses soumises a des sollicitations elevees de frottement
EP0165104A1 (de) Reparaturverfahren mittels Diffusion
CA2715174C (fr) Procede de revetement d'une bande metallique et installation de mise en oeuvre du procede
EP2331672A1 (de) Verfahren zur abreinigung von oberflächen mittels einer protischen ionischen flüssigkeit
EP0497663B1 (de) Verfahren zum Herstellen von korrosions-beständigen Eisenmetallwerkstücken mit Beibehaltung ihrer Reibungseigenschaften durch Nitrieren und anschliessendem Oxidieren
EP3049545B1 (de) Verfahren zur abscheidung einer antikorrosionsbeschichtung
EP0493280B1 (de) Kupferrohre mit verbesserter Korrosionsbeständigkeit sowie Verfahren zu ihrer Herstellung
FR2524005A1 (fr) Procede de revetement d'un substrat forme d'un alliage thermo-resistant
FR2554831A1 (fr) Procede de depot d'un revetement protecteur sur des pieces metalliques
EP1963545B1 (de) Behandlungsverfahren der metallischen oberflächen durch carboxilierung, benutzung dieses verfahrens für den zeitweiligen korrosionsschutz und verfahren zur herstellung eines geformten carboxylierten bleches
EP3315214B1 (de) Verfahren zur epilamisierung eines elements einer uhr oder eines schmuckstücks
EP1373597B1 (de) Verfahren zur behandlung von metalloberflächen durch carboxylierung
EP0517586B1 (de) Verfahren zum Erzeugen einer Antikorrosionsbeschichtung auf Copolymerbasis auf einer Metalloberfläche
EP0638661B1 (de) Verfahren zur Verbesserung des Verschleissfestigkeit und Korrosionswiderstand von Eisenmetalgegenständen
CA2962057A1 (fr) Traitement de surface de substrats metalliques
EP0085626B1 (de) Zusammensetzung und Verfahren zur Behandlung von phosphatierten Metalloberflächen
WO2021058927A1 (fr) Composition chimique pour retirer des residus en alliage nickel-platine d'un substrat, et procede de retrait de tels residus
FR2673647A1 (fr) Procede de fabrication d'alliages de cuivre durcis par oxydation interne.
BE335276A (de)
FR2794134A1 (fr) Procede de fabrication de surfaces protegees, plus specialement protegees contre la corrosion
LU85333A1 (fr) Procede de protection d'un produit metallique contre l'oxydation pendant la trempe
BE829813A (fr) Procede de boruration de surfaces metalliques
BE645102A (de)
BE437790A (de)
BE680347A (de)

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 ES GB IT

17P Request for examination filed

Effective date: 19920718

17Q First examination report despatched

Effective date: 19931012

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES GB IT

REF Corresponds to:

Ref document number: 69115237

Country of ref document: DE

Date of ref document: 19960118

ITF It: translation for a ep patent filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2080282

Country of ref document: ES

Kind code of ref document: T3

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19960122

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: ES

Payment date: 19991209

Year of fee payment: 9

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

Ref country code: DE

Payment date: 20000121

Year of fee payment: 9

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

Ref country code: GB

Payment date: 20001214

Year of fee payment: 10

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

Ref country code: ES

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

Effective date: 20001221

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

Ref country code: DE

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

Effective date: 20011002

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

Ref country code: GB

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

Effective date: 20011220

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

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

Effective date: 20011220

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20020112

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

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20051220