[go: up one dir, main page]

EP2354277A1 - Method for protecting a metal substrate against corrosion and abrasion, and metal substrate obtained through said method - Google Patents

Method for protecting a metal substrate against corrosion and abrasion, and metal substrate obtained through said method Download PDF

Info

Publication number
EP2354277A1
EP2354277A1 EP11153074A EP11153074A EP2354277A1 EP 2354277 A1 EP2354277 A1 EP 2354277A1 EP 11153074 A EP11153074 A EP 11153074A EP 11153074 A EP11153074 A EP 11153074A EP 2354277 A1 EP2354277 A1 EP 2354277A1
Authority
EP
European Patent Office
Prior art keywords
coating
nickel
polishing
alloy
substrate
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Withdrawn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
EP11153074A
Other languages
German (de)
French (fr)
Inventor
Sylvie Guibert-Claverie
Yvan Thareau
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.)
Dalic Laboratoire SA
Original Assignee
Dalic Laboratoire SA
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 Dalic Laboratoire SA filed Critical Dalic Laboratoire SA
Publication of EP2354277A1 publication Critical patent/EP2354277A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/56—Electroplating: Baths therefor from solutions of alloys
    • C25D3/565—Electroplating: Baths therefor from solutions of alloys containing more than 50% by weight of zinc
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/04—Electroplating with moving electrodes
    • C25D5/06—Brush or pad plating
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
    • C25D5/48—After-treatment of electroplated surfaces
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/12—All metal or with adjacent metals
    • Y10T428/12493—Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
    • Y10T428/12736—Al-base component

Definitions

  • the present invention relates to a method for protecting a metal substrate, especially aluminum alloy, against corrosion and abrasion.
  • Such a method finds particular application in the field of aeronautics, a field in which some aircraft parts, made of aluminum alloy, are subjected in flight to phenomena of abrasion and corrosion; these same parts are more likely to be scratched or subjected to shocks during their stay on the ground or their manufacture.
  • the first of these processes comprises an anodizing treatment (carried out in a tank), of chromic or sulfuric type, of said parts, followed by the application of a protective paint and / or a varnish on the parts thus treated.
  • the second of these methods comprises the use at these parts of aircraft of an aluminum sheet coated with an aluminum veneer, this veneer being polished to give it a finish called polished mirror.
  • the method based on anodizing does not allow obtaining the required polish in some cases.
  • the coatings obtained with the known method of polished veneer are difficult to repair; indeed, in this case, the repair requires sanding which may affect the substrate-plating integrity by perforating the latter and result in the replacement of the sheet which is a very complex and expensive operation.
  • the purpose of the present invention is to overcome these shortcomings of the processes of the prior art and, for this purpose, it proposes a method of protecting a metal substrate, in particular aluminum alloy, against corrosion and abrasion, which is characterized in that it comprises forming on said substrate a coating of zinc alloy and nickel (abbreviated as Zn-Ni), and then polishing the coating thus formed.
  • a metal substrate in particular aluminum alloy
  • Zn-Ni zinc alloy and nickel
  • This coating has a good adhesion to the substrate, as well as a higher hardness (250-300HV) than that obtained with non-anodized aluminum (25-120HV).
  • the treated substrate thus has, because of its increased hardness, better protection against abrasion, scratches and shocks, which increases the intervals between the maintenance operations and facilitates the maintenance itself.
  • This treated substrate is also superior, in terms of corrosion resistance, to polished aluminum substrates.
  • a treated substrate makes it possible to obtain a salt spray protection time of more than 400 hours before the appearance of corrosion on this substrate, whereas in the case of the plated and polished aluminum process, the corrosion appears in the 20 first hours of exposure to salt spray.
  • the choice of the Zn-Ni alloy generates a galvanic couple with the aluminum substrate favorable to its protection, also in the case where a local repair (case of pitting or deep shocks) would have been carried out using a deposit of nickel if it is covered with a Zinc-Nickel finish.
  • the coating according to the invention is, in case of appearance of cracks or scratches, repairable by simple localized Zn-Ni alloy contribution by the technique of electrolysis buffer, followed by polishing of the areas concerned by this alloy contribution.
  • the polished-mirror appearance obtained according to the invention by the polishing operation is at least as good as that currently obtained by polishing. aluminum plating, thereby improving airflow and therefore could generate fuel savings over an unpolished structure.
  • it may be used for the deposition of Zn-Ni to the well-known electrolytic deposition technique, in particular out of the tank, for example by electrolysis to the buffer, which makes it possible to treat the substrate locally. , retain its geometric stability and is ideally suited to the manufacturing cycle of these parts that may require assembly and protection by other processes on their other side.
  • the electrolytic deposition comprises the implementation of an electrolytic solution containing Ni 2+ and Zn 2+ ions, the concentration of Ni 2+ ions being 9 to 49g / L and the concentration of Zn 2+ ions being 49 to 90g / L.
  • said concentrations of Ni 2+ and Zn 2+ ions are chosen to form a coating comprising 5 to 20% by weight, preferably 10 to 14% by weight, of nickel.
  • the source of Ni 2+ ions may, for example, comprise nickel chloride (for example hydrated) and the Zn 2+ ion source may, for example, comprise zinc oxide.
  • the polishing of the Zn-Ni alloy coating is not limited to a particular technique and may involve manual or mechanical sanding (especially rotary sander or robot), in particular with the aid of a abrasive material such as abrasive paper or polishing paste.
  • the formation of the zinc-nickel alloy coating and the polishing are for example carried out to obtain, before polishing, a coating with a thickness of 30 to 50 ⁇ m and after polishing, a coating with a thickness of 20 ⁇ m. at 45 ⁇ m.
  • the method according to the invention may further advantageously include the application, on the polished nickel-zinc alloy coating, of a transparent and airtight surface coating.
  • This surface coating for example applied by spraying, aerosol or with a brush, of variable thickness up to 40 ⁇ m depending on the case, may include among others one or more polymers selected from the group consisting of acrylic resins, epoxy resins silicones, polysilanes, soils-gels and polyurethanes, or be the result of passivation without hexavalent chromium.
  • This surface coating will in particular make it possible to delay and limit the oxidation of the Zn-Ni coating which occurs mainly in humid and marine atmospheres.
  • the metal substrate to be treated it may be aluminum alloy substrates (for example alloy 2024 or 2219) or steel substrates, generally exposed to abrasion and corrosion phenomena, as is the case. in the aeronautical field, from leading edges or wingtips, fins or fins of aircraft, aircraft engine nacelle air inlets, window frames or airplane cockpits, blade edges of airplane or helicopter propellers and certain landing gear components.
  • aluminum alloy substrates for example alloy 2024 or 2219
  • steel substrates generally exposed to abrasion and corrosion phenomena, as is the case. in the aeronautical field, from leading edges or wingtips, fins or fins of aircraft, aircraft engine nacelle air inlets, window frames or airplane cockpits, blade edges of airplane or helicopter propellers and certain landing gear components.
  • the present invention also relates to the protected metal substrate obtained by the method described above, wherein the coating has a mirror polish.
  • the application of the nickel-zinc alloy coating is preferably preceded by the preparation of the surface of the substrate to be treated.
  • This preparation is intended to degrease this surface and, if necessary, to strip the latter, to remove fats, impurities and surface oxides and thus allow optimal adhesion of the coating.
  • said preparation may comprise sanding followed by one or more of the following operations: chemical or electrochemical degreasing, chemical or electrochemical etching, wet or dry sandblasting, chemical or electrochemical depassivation, chemical or electrochemical activation and possible formation of a metal underlayer, with rinsing with water between these different operations.
  • the zinc-nickel coating it is preferably uses the technique of electrolytic deposition, out of the tank.
  • the substrate having received its coating After rinsing the substrate having received its coating, it is subjected to a polishing operation using the techniques listed above, until a mirror polish corresponding to the requirements of the manufacturers and their customers is obtained. .
  • the above process is completed by an application step, on the polished Zn-Ni coating, of an airtight surface coating, for example by spraying, having the thickness and the composition referred to above.
  • Some features of the polished Zn-Ni coating have been tested, including its substrate adhesion, hardness, corrosion resistance, and thermal shock resistance.
  • the adhesion to the substrate was verified by micrographic cross-section, during polishing operations that solicit deposition in a significant manner and during thermal shock tests with 9 cycles between -80 ° C and + 200 ° C, with passage direct from one temperature to another.
  • the hardness was measured by conventional methods recognized.
  • Corrosion resistance was verified in neutral salt spray tests carried out according to ISO 9227 and ASTM B117, possibly after thermal shock as described above.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electroplating Methods And Accessories (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)

Abstract

The process comprises forming an alloy coating of zinc and nickel on a substrate, polishing the formed alloy coating, and applying a transparent and airtight surface coating on the polished coating alloy. The formation of the alloy coating comprises electrolytic deposition that is carried out at a tank including an electrolysis buffer. The electrolytic deposition comprises implementation of an electrolytic solution having nickel ion source having a concentration of 9-49 g/l and zinc ion source having a concentration of 49-90 g/l. The electrolytic solution has a pH of 8-10. The process comprises forming an alloy coating of zinc and nickel on a substrate, polishing the formed alloy coating, and applying a transparent and airtight surface coating on the polished coating alloy. The formation of the alloy coating comprises electrolytic deposition that is carried out at a tank including an electrolysis buffer. The electrolytic deposition comprises implementation of an electrolytic solution having nickel ion source having a concentration of 9-49 g/l and zinc ion source having a concentration of 49-90 g/l. The electrolytic solution has a pH of 8-10. The polishing step is performed by manual or mechanical sanding. The alloy coating has a thickness of 30-50 mu m before polishing, and a thickness of 20-45 mu m after polishing. The surface coating has a thickness of 40 mu m, and provides a free hexavalent chromium passivation. An independent claim is included for a metallic substrate.

Description

La présente invention a pour objet un procédé de protection d'un substrat métallique, notamment en alliage d'aluminium, contre la corrosion et l'abrasion.The present invention relates to a method for protecting a metal substrate, especially aluminum alloy, against corrosion and abrasion.

Un tel procédé trouve en particulier son application dans le domaine de l'aéronautique, domaine dans lequel certaines parties d'aéronefs, réalisées en alliage d'aluminium, sont soumises en vol à des phénomènes d'abrasion et de corrosion; ces mêmes parties sont de plus susceptibles d'être rayées ou soumises à des chocs lors de leur séjour au sol ou de leur fabrication.Such a method finds particular application in the field of aeronautics, a field in which some aircraft parts, made of aluminum alloy, are subjected in flight to phenomena of abrasion and corrosion; these same parts are more likely to be scratched or subjected to shocks during their stay on the ground or their manufacture.

Il existe en outre dans ce même domaine de l'aéronautique, une demande pour que certaines surfaces extérieures d'aéronefs aient un aspect brillant.In the same field of aeronautics, there is also a demand for certain exterior surfaces of aircraft to have a shiny appearance.

A ce jour, les parties d'aéronefs susvisées sont protégées essentiellement par deux procédés.To date, the aforementioned aircraft parts are essentially protected by two methods.

Le premier de ces procédés comprend un traitement d'anodisation (réalisé en cuve), de type chromique ou sulfurique, desdites parties, suivi de l'application d'une peinture protectrice et/ou d'un vernis sur les parties ainsi traitées.The first of these processes comprises an anodizing treatment (carried out in a tank), of chromic or sulfuric type, of said parts, followed by the application of a protective paint and / or a varnish on the parts thus treated.

Le second de ces procédés comprend l'utilisation au niveau de ces parties d'aéronefs d'une tôle d'aluminium revêtue d'un placage d'aluminium, ce placage étant poli afin de lui conférer une finition dite poli-miroir.The second of these methods comprises the use at these parts of aircraft of an aluminum sheet coated with an aluminum veneer, this veneer being polished to give it a finish called polished mirror.

Ces procédés présentent de multiples inconvénients.These methods have many disadvantages.

Ainsi, ils ne permettent pas une protection suffisante contre la corrosion, l'abrasion, les rayures et les chocs avec pour conséquence préjudiciable, des pertes d'épaisseur (fragilisation) et la formation de piqûres de corrosion localisées et de profondeur variable.Thus, they do not allow sufficient protection against corrosion, abrasion, scratches and shocks with detrimental consequence, loss of thickness (embrittlement) and the formation of localized corrosion pits and variable depth.

De plus, le procédé basé sur l'anodisation ne permet pas l'obtention du poli exigé dans certains cas.In addition, the method based on anodizing does not allow obtaining the required polish in some cases.

Par ailleurs, l'utilisation d'un placage, qui représente habituellement de 5 à 10% de l'épaisseur des parties d'aéronefs concernées, est de mise en oeuvre délicate et entraine un surcoût de matière appréciable.Moreover, the use of a veneer, which usually represents 5 to 10% of the thickness of the parts of aircraft concerned, is difficult to implement and entails significant additional cost of material.

En outre, les revêtements obtenus avec le procédé connu du placage poli, sont difficilement réparables ; en effet, dans ce cas, la réparation exige un ponçage qui peut affecter l'intégrité substrat-placage en perforant ce dernier et aboutir au remplacement de la tôle qui est une opération très complexe et coûteuse.In addition, the coatings obtained with the known method of polished veneer, are difficult to repair; indeed, in this case, the repair requires sanding which may affect the substrate-plating integrity by perforating the latter and result in the replacement of the sheet which is a very complex and expensive operation.

Le but de la présente invention est de pallier ces insuffisances des procédés de la technique antérieure et, à cet effet, elle propose un procédé de protection d'un substrat métallique, notamment en alliage d'aluminium, contre la corrosion et l'abrasion, qui est caractérisé en ce qu'il comprend la formation sur ledit substrat d'un revêtement en alliage de zinc et de nickel (en abrégé Zn-Ni), puis le polissage du revêtement ainsi formé.The purpose of the present invention is to overcome these shortcomings of the processes of the prior art and, for this purpose, it proposes a method of protecting a metal substrate, in particular aluminum alloy, against corrosion and abrasion, which is characterized in that it comprises forming on said substrate a coating of zinc alloy and nickel (abbreviated as Zn-Ni), and then polishing the coating thus formed.

Ce revêtement présente une bonne adhérence au substrat, ainsi qu'une dureté plus élevée (250-300HV) que celle obtenue avec l'aluminium non anodisé (25-120HV).This coating has a good adhesion to the substrate, as well as a higher hardness (250-300HV) than that obtained with non-anodized aluminum (25-120HV).

Le substrat traité présente donc, en raison de sa dureté accrue, une meilleure protection contre l'abrasion, les rayures et les chocs, ce qui augmente les intervalles entre les opérations d'entretien et facilite l'entretien lui-même.The treated substrate thus has, because of its increased hardness, better protection against abrasion, scratches and shocks, which increases the intervals between the maintenance operations and facilitates the maintenance itself.

Ce substrat traité est également supérieur, en termes de résistance à la corrosion, aux substrats d'aluminium polis.This treated substrate is also superior, in terms of corrosion resistance, to polished aluminum substrates.

Ainsi, un substrat traité permet d'obtenir une durée de protection en brouillard salin de plus de 400 heures avant apparition de la corrosion sur ce substrat, alors que dans le cas du procédé d'aluminium plaqué et poli, la corrosion apparaît dans les 20 premières heures d'exposition au brouillard salin.Thus, a treated substrate makes it possible to obtain a salt spray protection time of more than 400 hours before the appearance of corrosion on this substrate, whereas in the case of the plated and polished aluminum process, the corrosion appears in the 20 first hours of exposure to salt spray.

En outre, le choix de l'alliage Zn-Ni génère un couple galvanique avec le substrat en aluminium favorable à sa protection, également dans le cas où une réparation locale (cas de piqûres ou chocs profonds) aurait été réalisée en utilisant un dépôt de nickel si on recouvre ce dernier d'une couche de finition de Zinc-Nickel.In addition, the choice of the Zn-Ni alloy generates a galvanic couple with the aluminum substrate favorable to its protection, also in the case where a local repair (case of pitting or deep shocks) would have been carried out using a deposit of nickel if it is covered with a Zinc-Nickel finish.

Par ailleurs, le revêtement selon l'invention est, en cas d'apparition de fissures ou rayures, réparable par simple apport localisé d'alliage Zn-Ni par la technique d'électrolyse au tampon, suivi d'un polissage des zones concernées par cet apport d'alliage.Furthermore, the coating according to the invention is, in case of appearance of cracks or scratches, repairable by simple localized Zn-Ni alloy contribution by the technique of electrolysis buffer, followed by polishing of the areas concerned by this alloy contribution.

Outre le fait qu'il répond parfaitement aux contraintes d'esthétique imposées par certaines compagnies aériennes, l'aspect poli-miroir obtenu selon l'invention par l'opération de polissage est au moins d'aussi bonne qualité que celui obtenu actuellement par polissage d'un placage d"aluminium ; il permet de ce fait une amélioration de l'écoulement de l'air et par conséquent pourrait générer un gain de carburant par rapport à une structure non polie.In addition to the fact that it perfectly meets the aesthetic constraints imposed by certain airlines, the polished-mirror appearance obtained according to the invention by the polishing operation is at least as good as that currently obtained by polishing. aluminum plating, thereby improving airflow and therefore could generate fuel savings over an unpolished structure.

Selon un mode de réalisation préféré, il peut être fait appel pour le dépôt de Zn-Ni à la technique bien connue de dépôt par voie électrolytique, en particulier hors cuve, par exemple par électrolyse au tampon, ce qui permet de traiter localement le substrat, de conserver sa stabilité géométrique et convient parfaitement au cycle de fabrication de ces pièces qui peuvent nécessiter des assemblages et une protection par d'autres procédés sur leur autre face.According to a preferred embodiment, it may be used for the deposition of Zn-Ni to the well-known electrolytic deposition technique, in particular out of the tank, for example by electrolysis to the buffer, which makes it possible to treat the substrate locally. , retain its geometric stability and is ideally suited to the manufacturing cycle of these parts that may require assembly and protection by other processes on their other side.

Selon un mode de réalisation, le dépôt par voie électrolytique comprend la mise en oeuvre d'une solution électrolytique contenant des ions Ni2+ et Zn2+, la concentration des ions Ni2+ étant de 9 à 49g/L et la concentration des ions Zn2+ étant de 49 à 90g/L.According to one embodiment, the electrolytic deposition comprises the implementation of an electrolytic solution containing Ni 2+ and Zn 2+ ions, the concentration of Ni 2+ ions being 9 to 49g / L and the concentration of Zn 2+ ions being 49 to 90g / L.

Avantageusement, lesdites concentrations en ions Ni2+ et Zn2+ sont choisies pour former un revêtement comprenant 5 à 20% en poids, de préférence 10 à 14% en poids, de nickel.Advantageously, said concentrations of Ni 2+ and Zn 2+ ions are chosen to form a coating comprising 5 to 20% by weight, preferably 10 to 14% by weight, of nickel.

On ajoutera que la source d'ions Ni2+ pourra par exemple comprendre du chlorure de nickel (par exemple hydraté) et la source d'ions Zn2+ pourra par exemple comprendre de l'oxyde de zinc.It will be added that the source of Ni 2+ ions may, for example, comprise nickel chloride (for example hydrated) and the Zn 2+ ion source may, for example, comprise zinc oxide.

Selon l'invention, le polissage du revêtement en alliage Zn-Ni n'est pas limité à une technique particulière et peut faire appel à un ponçage manuel ou mécanique (notamment ponceuse rotative ou robot), en particulier à l'aide d'un matériau abrasif tel qu'un papier abrasif ou une pâte de polissage.According to the invention, the polishing of the Zn-Ni alloy coating is not limited to a particular technique and may involve manual or mechanical sanding (especially rotary sander or robot), in particular with the aid of a abrasive material such as abrasive paper or polishing paste.

Selon l'invention, la formation du revêtement en alliage de zinc-nickel et le polissage sont par exemple réalisés pour obtenir, avant polissage, un revêtement d'une épaisseur de 30 à 50µm et après polissage, un revêtement d'une épaisseur de 20 à 45µm.According to the invention, the formation of the zinc-nickel alloy coating and the polishing are for example carried out to obtain, before polishing, a coating with a thickness of 30 to 50 μm and after polishing, a coating with a thickness of 20 μm. at 45μm.

Le procédé selon l'invention peut en outre avantageusement comprendre l'application, sur le revêtement poli en alliage de nickel et de zinc, d'un revêtement de surface transparent et étanche à l'air.The method according to the invention may further advantageously include the application, on the polished nickel-zinc alloy coating, of a transparent and airtight surface coating.

Ce revêtement de surface, par exemple appliqué par pulvérisation, aérosol ou au pinceau, d'une épaisseur variable jusqu'à 40µm selon les cas, peut entre autres comprendre un ou plusieurs polymères choisis dans le groupe constitué par les résines acryliques, les résines époxy, les silicones, les polysilanes, les sols-gels et les polyuréthanes, ou être le résultat d'une passivation sans chrome hexavalent.This surface coating, for example applied by spraying, aerosol or with a brush, of variable thickness up to 40 μm depending on the case, may include among others one or more polymers selected from the group consisting of acrylic resins, epoxy resins silicones, polysilanes, soils-gels and polyurethanes, or be the result of passivation without hexavalent chromium.

A titre d'exemples, on peut citer les compositions pour revêtement de surface commercialisées par les sociétés Socomor, Coventya, Cytec, Map et Akzo Nobel.By way of examples, mention may be made of the surface-coating compositions marketed by the companies Socomor, Coventya, Cytec, Map and Akzo Nobel.

Ledit revêtement de surface permettra notamment de retarder et de limiter l'oxydation du revêtement de Zn-Ni qui se produit surtout dans les atmosphères humides et marines.This surface coating will in particular make it possible to delay and limit the oxidation of the Zn-Ni coating which occurs mainly in humid and marine atmospheres.

Quant au substrat métallique à traiter, il peut s'agir de substrats en alliage d'aluminium (par exemple alliage 2024 ou 2219) ou de substrats en acier, généralement exposés à des phénomènes d'abrasion et de corrosion, comme cela est le cas dans le domaine aéronautique, de bords d'attaque ou becs d'ailes, d'ailerons ou de dérives d'avion, d'entrées d'air de nacelle de moteur d'avion, de bâtis de hublots ou cockpits d'avion, d'arêtes de pales d'hélices d'avion ou d'hélicoptère et de certains éléments de trains d'atterrissage.As for the metal substrate to be treated, it may be aluminum alloy substrates (for example alloy 2024 or 2219) or steel substrates, generally exposed to abrasion and corrosion phenomena, as is the case. in the aeronautical field, from leading edges or wingtips, fins or fins of aircraft, aircraft engine nacelle air inlets, window frames or airplane cockpits, blade edges of airplane or helicopter propellers and certain landing gear components.

La présente invention a également pour objet le substrat métallique protégé obtenu par le procédé décrit ci-dessus, dans lequel le revêtement présente un poli miroir.The present invention also relates to the protected metal substrate obtained by the method described above, wherein the coating has a mirror polish.

La présente invention va maintenant être illustrée par la description additionnelle ci-après.The present invention will now be illustrated by the additional description hereinafter.

L'application du revêtement en alliage de nickel et de zinc est de préférence précédée par la préparation de la surface du substrat à traiter.The application of the nickel-zinc alloy coating is preferably preceded by the preparation of the surface of the substrate to be treated.

Cette préparation a pour but de dégraisser cette surface et, si besoin est, de décaper cette dernière, pour en éliminer les graisses, impuretés et oxydes superficiels et ainsi permettre une adhérence optimale du revêtement.This preparation is intended to degrease this surface and, if necessary, to strip the latter, to remove fats, impurities and surface oxides and thus allow optimal adhesion of the coating.

Selon la nature du substrat (alliage d'aluminium ou acier) et l'état de surface de celui-ci, ladite préparation peut comprendre un ponçage suivi d'une ou plusieurs des opérations suivantes : dégraissage chimique ou électrochimique, décapage chimique ou électrochimique, sablage par voie humide ou à sec, dépassivation chimique ou électrochimique, activation chimique ou électrochimique et formation éventuelle d'une sous-couche métallique, avec rinçage à l'eau entre ces différentes opérations.Depending on the nature of the substrate (aluminum alloy or steel) and the surface condition thereof, said preparation may comprise sanding followed by one or more of the following operations: chemical or electrochemical degreasing, chemical or electrochemical etching, wet or dry sandblasting, chemical or electrochemical depassivation, chemical or electrochemical activation and possible formation of a metal underlayer, with rinsing with water between these different operations.

Pour réaliser le revêtement de zinc-nickel, il est de préférence fait appel à la technique de dépôt par voie électrolytique, hors cuve.To achieve the zinc-nickel coating, it is preferably uses the technique of electrolytic deposition, out of the tank.

A cet effet, utilisation peut être faite d'outils d'électrolyse au tampon bien connus. Les conditions mises en oeuvre pour le dépôt électrolytique sont les suivantes :

  • composition de l'électrolyte :
    • Oxyde de zinc : 62 à 113g/L
    • Chlorure de nickel hexahydraté : 38 à 205g/L
    • Acide sulfamique : quantité nécessaire pour la dissolution du sel de zinc
    • Agent basique : quantité nécessaire pour ajuster le pH entre 8 et 10
    • Eau déminéralisée : pour ajuster au volume
  • anode : graphite, titane platiné, platine
  • courant : continu ou pulsé
  • tension : inférieure à 20V
  • densité de courant : 50 à 300A/dm2
  • durée : 7,7 à 9,6 minutes pour une épaisseur de dépôt de 40 à 50µm sur 1 dm2, en considérant une couverture d'électrode de 10 % de la surface à traiter et une densité de courant de 200A/dm2 en contact.
For this purpose, use may be made of well known buffer electrolysis tools. The conditions used for the electrolytic deposition are as follows:
  • composition of the electrolyte:
    • Zinc oxide: 62 to 113g / L
    • Nickel chloride hexahydrate: 38 to 205g / L
    • Sulfamic acid: quantity required for the dissolution of zinc salt
    • Basic agent: quantity needed to adjust the pH between 8 and 10
    • Demineralized water: to adjust to the volume
  • anode: graphite, platinum titanium, platinum
  • current: continuous or pulsed
  • voltage: less than 20V
  • current density: 50 to 300A / dm 2
  • duration: 7.7 to 9.6 minutes for a deposition thickness of 40 to 50 μm over 1 dm 2 , considering an electrode coverage of 10% of the surface to be treated and a current density of 200 A / dm 2 in contact.

Après rinçage du substrat ayant reçu son revêtement, celui-ci est soumis à une opération de polissage par mise en oeuvre des techniques listées ci-dessus, jusqu'à l'obtention d'un poli miroir correspondant aux exigences des constructeurs et de leurs clients.After rinsing the substrate having received its coating, it is subjected to a polishing operation using the techniques listed above, until a mirror polish corresponding to the requirements of the manufacturers and their customers is obtained. .

Si on le souhaite, on complète le procédé ci-dessus par une étape d'application, sur le revêtement de Zn-Ni poli, d'un revêtement de surface étanche à l'air, par exemple par pulvérisation, ayant l'épaisseur et la composition susvisées.If desired, the above process is completed by an application step, on the polished Zn-Ni coating, of an airtight surface coating, for example by spraying, having the thickness and the composition referred to above.

Certaines caractéristiques du revêtement de Zn-Ni poli ont été testées, notamment son adhérence au substrat, sa dureté, sa résistance à la corrosion et sa résistance aux chocs thermiques.Some features of the polished Zn-Ni coating have been tested, including its substrate adhesion, hardness, corrosion resistance, and thermal shock resistance.

L'adhérence au substrat a été vérifiée par coupe micrographique, lors des opérations de polissage qui sollicitent le dépôt d'une façon importante et lors d'essais de chocs thermiques comportant 9 cycles entre -80°C et +200°C, avec passage direct d'une température à l'autre.The adhesion to the substrate was verified by micrographic cross-section, during polishing operations that solicit deposition in a significant manner and during thermal shock tests with 9 cycles between -80 ° C and + 200 ° C, with passage direct from one temperature to another.

La dureté a été mesurée par des méthodes conventionnelles reconnues.The hardness was measured by conventional methods recognized.

La résistance à la corrosion a été vérifiée lors d'essais comparatifs en brouillard salin neutre réalisés selon les normes ISO 9227 et ASTM B117, éventuellement après soumission aux chocs thermiques décrits plus haut.Corrosion resistance was verified in neutral salt spray tests carried out according to ISO 9227 and ASTM B117, possibly after thermal shock as described above.

Il a aussi été vérifié que le revêtement ne réduit pas la tenue en fatigue des pièces traitées ; en effet, il n'est noté aucun abattement sur la tenue en fatigue amorçage.It has also been verified that the coating does not reduce the fatigue strength of the treated parts; indeed, it is noted no reduction on fatigue fatigue priming.

Claims (12)

Procédé de protection d'un substrat métallique d'une partie d'aéronef, notamment en alliage d'aluminium, contre la corrosion et l'abrasion, caractérisé en ce qu'il comprend la formation sur ledit substrat d'un revêtement en alliage de zinc et de nickel, puis polissage du revêtement ainsi formé.A method of protecting a metal substrate of an aircraft part, in particular an aluminum alloy, against corrosion and abrasion, characterized in that it comprises the formation on said substrate of a coating of alloy of zinc and nickel, then polishing the coating thus formed. Procédé selon la revendication 1, caractérisé en ce que la formation dudit revêtement comprend le dépôt par voie électrolytique.Process according to claim 1, characterized in that the formation of said coating comprises electrolytic deposition. Procédé selon la revendication 2, caractérisé en ce que le dépôt par voie électrolytique est réalisé hors cuve, notamment par électrolyse au tampon.Process according to Claim 2, characterized in that the electrolytic deposition is carried out out of the tank, in particular by electrolysis with the buffer. Procédé selon la revendication 2 ou 3, caractérisé en ce que le dépôt par voie électrolytique comprend la mise en oeuvre d'une solution électrolytique ayant une concentration en ions Ni2+ de 9 à 49g/L et une concentration en ions Zn2+ de 49 à 90g/L.Process according to Claim 2 or 3, characterized in that the electrolytic deposition comprises the use of an electrolytic solution having a concentration of Ni 2+ ions of 9 to 49 g / L and a concentration of Zn 2+ ions of 49 to 90g / L. Procédé selon la revendication 4, caractérisé en ce que la source d'ions Ni2+ comprend du chlorure de nickel et la source d'ions Zn2+ comprend de l'oxyde de zinc, la solution électrolytique ayant un pH de 8 à 10.Process according to Claim 4, characterized in that the Ni 2+ ion source comprises nickel chloride and the Zn 2+ ion source comprises zinc oxide, the electrolytic solution having a pH of 8 to 10 . Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que le polissage est effectué par ponçage manuel ou mécanique.Method according to one of the preceding claims, characterized in that the polishing is carried out by manual or mechanical sanding. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que la formation du revêtement en alliage de nickel et de zinc et le polissage sont réalisés pour obtenir, avant polissage, un revêtement d'une épaisseur de 30 à 50 µm et, après polissage, un revêtement d'une épaisseur de 20 à 45µm.Process according to any one of the preceding claims, characterized in that the formation of the nickel-zinc alloy coating and the polishing are carried out in order to obtain, before polishing, a coating with a thickness of 30 to 50 μm and, after polishing, a coating with a thickness of 20 to 45μm. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comprend en outre l'application, sur le revêtement poli en alliage de zinc et de nickel, d'un revêtement de surface transparent et étanche à l'air.Method according to one of the preceding claims, characterized in that it further comprises the application, on the polished zinc alloy and nickel coating, of a transparent and airtight surface coating. Procédé selon la revendication 8, caractérisé en ce que ledit revêtement de surface présente une épaisseur pouvant aller jusqu'à 40µm et comprend un ou plusieurs polymères choisis dans le groupe constitué par les résines acryliques, les résines époxy, les silicones, les polysilanes, les sols-gels et les polyuréthanes, ou est le résultat d'une passivation sans chrome hexavalent.Process according to claim 8, characterized in that said surface coating has a thickness of up to 40 μm and comprises one or more polymers selected from the group consisting of acrylic resins, epoxy resins, silicones, polysilanes, Soil-gels and polyurethanes, or is the result of passivation without hexavalent chromium. Substrat métallique, notamment en alliage d'aluminium obtenu selon l'une des revendications 1 à 9, caractérisé en ce qu'il comprend un revêtement constitué d'un alliage de zinc et de nickel, ce revêtement présentant un aspect poli miroir.Metal substrate, especially aluminum alloy obtained according to one of claims 1 to 9, characterized in that it comprises a coating consisting of a zinc alloy and nickel, this coating having a mirror polished appearance. Substrat selon la revendication 10, caractérisé en ce que ledit revêtement a une épaisseur de 20 à 45µm et comprend de 5 à 20% en poids de nickel.Substrate according to claim 10, characterized in that said coating has a thickness of 20 to 45 μm and comprises from 5 to 20% by weight of nickel. Substrat selon la revendication 10 ou 11, caractérisé en ce qu'il comprend en outre un revêtement de surface transparent et étanche à l'air, appliqué sur le revêtement poli.Substrate according to claim 10 or 11, characterized in that it further comprises a transparent and airtight surface coating applied to the polished coating.
EP11153074A 2010-02-08 2011-02-02 Method for protecting a metal substrate against corrosion and abrasion, and metal substrate obtained through said method Withdrawn EP2354277A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR1050861A FR2956123B1 (en) 2010-02-08 2010-02-08 METHOD FOR PROTECTING A METAL SUBSTRATE AGAINST CORROSION AND ABRASION, AND METAL SUBSTRATE OBTAINED BY THIS METHOD.

Publications (1)

Publication Number Publication Date
EP2354277A1 true EP2354277A1 (en) 2011-08-10

Family

ID=42335233

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11153074A Withdrawn EP2354277A1 (en) 2010-02-08 2011-02-02 Method for protecting a metal substrate against corrosion and abrasion, and metal substrate obtained through said method

Country Status (3)

Country Link
US (1) US20110195272A1 (en)
EP (1) EP2354277A1 (en)
FR (1) FR2956123B1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102358949A (en) * 2011-09-28 2012-02-22 中国人民解放军91872部队上海研究室 Aluminium alloy anticorrosion treatment technology
WO2022189728A1 (en) * 2021-03-10 2022-09-15 Safran Landing Systems Landing gear comprising static sealing points

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3038296B1 (en) * 2015-07-03 2017-08-25 Messier Bugatti Dowty LANDSCAPE COMPRISING A ZINC-NICKEL DEPOSIT RESISTANT TO CONTACT WEAR
US20200132894A1 (en) * 2018-10-31 2020-04-30 Corning Incorporated Support for reflective optical element

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58197292A (en) * 1982-05-14 1983-11-16 Nippon Steel Corp Manufacturing method for high-efficiency gamma-zinc nickel alloy coated steel sheet
WO1984001461A1 (en) * 1982-09-30 1984-04-12 Boeing Co Plated structure exhibiting low hydrogen embrittlement
CN87103824A (en) * 1987-05-27 1988-12-14 中国人民解放军装甲兵工程学院 Plated layer for imitation ancient bronze
KR100297797B1 (en) * 1997-12-31 2001-10-25 Hyundai Motor Co Ltd Method for manufacturing zinc-nickel alloy plated steel with superior corrosion resistance
US20040067314A1 (en) * 2002-10-07 2004-04-08 Joshi Nayan H. Aqueous alkaline zincate solutions and methods
US6800190B1 (en) * 2000-05-16 2004-10-05 Steven F. Wilcox Method to obtain a variety of surface colors by electroplating zinc nickel and nickel alloy oxides
US20050133376A1 (en) * 2003-12-19 2005-06-23 Opaskar Vincent C. Alkaline zinc-nickel alloy plating compositions, processes and articles therefrom
US20060198988A1 (en) * 2005-03-07 2006-09-07 Bryan Tullis Coated metal article and method of making same

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1232227A (en) * 1982-02-18 1988-02-02 Christopher Vance Manufacturing electrode by immersing substrate in aluminium halide and other metal solution and electroplating
US4481081A (en) * 1983-09-29 1984-11-06 The Boeing Company Method for brush plating conductive plastics
US4936941A (en) * 1988-04-08 1990-06-26 Ltv Aerospace And Defense Co. Automatic skin taping machine
JP2730695B2 (en) * 1989-04-10 1998-03-25 忠弘 大見 Tungsten film forming equipment
US5252195A (en) * 1990-08-20 1993-10-12 Mitsubishi Rayon Company Ltd. Process for producing a printed wiring board
JP3135915B2 (en) * 1990-08-31 2001-02-19 バリー，ベレズフォド トマス キングカム Cyanide-free plating bath for electrodeposition of tin-zinc alloys
US7037100B2 (en) * 2002-10-09 2006-05-02 3M Innovative Properties Company Apparatus for flame-perforating films and methods of flame-perforating films
US7442286B2 (en) * 2004-02-26 2008-10-28 Atotech Deutschland Gmbh Articles with electroplated zinc-nickel ternary and higher alloys, electroplating baths, processes and systems for electroplating such alloys
US8048285B2 (en) * 2005-05-11 2011-11-01 The Boeing Company Low hydrogen embrittlement zinc/nickel plating for high strength steels
EP1870495A1 (en) * 2006-06-21 2007-12-26 Atotech Deutschland Gmbh Aqueous alkaline, cyanide-free, bath for the galvanic deposition of Zinc and Zinc alloy layers
ES2553730T3 (en) * 2006-07-13 2015-12-11 Enthone, Incorporated Electrolyte composition and procedure for the deposition of a layer of zinc-nickel alloy on a cast iron or cast steel substrate

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58197292A (en) * 1982-05-14 1983-11-16 Nippon Steel Corp Manufacturing method for high-efficiency gamma-zinc nickel alloy coated steel sheet
WO1984001461A1 (en) * 1982-09-30 1984-04-12 Boeing Co Plated structure exhibiting low hydrogen embrittlement
CN87103824A (en) * 1987-05-27 1988-12-14 中国人民解放军装甲兵工程学院 Plated layer for imitation ancient bronze
KR100297797B1 (en) * 1997-12-31 2001-10-25 Hyundai Motor Co Ltd Method for manufacturing zinc-nickel alloy plated steel with superior corrosion resistance
US6800190B1 (en) * 2000-05-16 2004-10-05 Steven F. Wilcox Method to obtain a variety of surface colors by electroplating zinc nickel and nickel alloy oxides
US20040067314A1 (en) * 2002-10-07 2004-04-08 Joshi Nayan H. Aqueous alkaline zincate solutions and methods
US20050133376A1 (en) * 2003-12-19 2005-06-23 Opaskar Vincent C. Alkaline zinc-nickel alloy plating compositions, processes and articles therefrom
US20060198988A1 (en) * 2005-03-07 2006-09-07 Bryan Tullis Coated metal article and method of making same

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Week 198947, Derwent World Patents Index; AN 1989-340338, XP002593868 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102358949A (en) * 2011-09-28 2012-02-22 中国人民解放军91872部队上海研究室 Aluminium alloy anticorrosion treatment technology
WO2022189728A1 (en) * 2021-03-10 2022-09-15 Safran Landing Systems Landing gear comprising static sealing points
FR3120602A1 (en) * 2021-03-10 2022-09-16 Safran Landing Systems Landing gear with static sealing points

Also Published As

Publication number Publication date
FR2956123B1 (en) 2017-10-27
FR2956123A1 (en) 2011-08-12
US20110195272A1 (en) 2011-08-11

Similar Documents

Publication Publication Date Title
EP2812467B1 (en) Method of anodising aluminum alloy pieces
EP2812462B1 (en) Method for the surface treatment of parts made of an aluminum or magnesium alloy
EP4097278B1 (en) Method for sealing aluminum alloys
US20080149492A1 (en) Surface dyeing process for metal articles
FR3017884A1 (en) DUST PROTECTION EDGE AND METHOD OF MANUFACTURE
CN110644031A (en) Treatment to reduce grain texture differential growth rate in mirror-modified anodized aluminum
EP1915473B1 (en) Pretreatment of magnesium substrates for electroplating
EP2354277A1 (en) Method for protecting a metal substrate against corrosion and abrasion, and metal substrate obtained through said method
EP1357206A2 (en) Anodisation process of an aluminium alloy element
KR20090075362A (en) Metal coating method and parts painted thereby
US20210156043A1 (en) Method for plating a metallic material onto a titanium substrate
KR101365663B1 (en) Method for treating surface of metal using anodizing process
KR20210125001A (en) Method for manufacturing corrosion-resistant aluminum-silicon alloy castings, such corrosion-resistant aluminum-silicon alloy castings and uses thereof
FR2941241A1 (en) Etching aluminum or its alloy surface, comprises contacting aluminum surface with hexavalent chromium-free aqueous solution comprising sulfuric acid, nitric acid, ferric sulfate and water at given temperature for specified period of time
EP4127274A1 (en) Method for depositing a coating onto a metal part and metal part obtained according to such a method
FR3162446A1 (en) A PROCESS FOR SEALABLES OF ALUMINUM ALLOYS USING A SILANE AND A PART BASED ON ALUMINUM OR AN ALUMINUM ALLOY OBTAINED BY THIS PROCESS
KR20220110806A (en) protective coating for metal
EP3864195A1 (en) Composition for chromium plating a substrate and chromium plating process using such a composition
FR3110605A1 (en) PROCESS AND INSTALLATION FOR TREATMENT OF METAL PARTS BY MICRO-ARC OXIDATION
FR3155543A1 (en) METHOD FOR SEALING ALUMINUM ALLOYS USING A TUNGSTEN SALT AND PART BASED ON ALUMINUM OR AN ALUMINUM ALLOY OBTAINED BY THIS METHOD
EP4310226A1 (en) Surface treatment method of aluminum material
WO2017207909A1 (en) Chromating method and component obtained by this method
WO2015092265A1 (en) Anticorrosion and antiwear method
FR3140382A1 (en) PROCESS FOR POST-ANODIZATION SEALING OF ALUMINUM AND ALUMINUM ALLOYS WITHOUT USING CHROME
BE876752A (en) STEEL MATERIALS SUBJECT TO SURFACE TREATMENT

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

AX Request for extension of the european patent

Extension state: BA ME

17P Request for examination filed

Effective date: 20111215

17Q First examination report despatched

Effective date: 20130617

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: 20160901