[go: up one dir, main page]

EP1664391A1 - Electropolishing method - Google Patents

Electropolishing method

Info

Publication number
EP1664391A1
EP1664391A1 EP04764662A EP04764662A EP1664391A1 EP 1664391 A1 EP1664391 A1 EP 1664391A1 EP 04764662 A EP04764662 A EP 04764662A EP 04764662 A EP04764662 A EP 04764662A EP 1664391 A1 EP1664391 A1 EP 1664391A1
Authority
EP
European Patent Office
Prior art keywords
electrolyte
weight
electropolishing
phosphoric acid
iii
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
EP04764662A
Other languages
German (de)
French (fr)
Other versions
EP1664391B1 (en
Inventor
Siegfried Piesslinger-Schweiger
Olaf BÖHME
Razmik Abedian
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.)
Poligrat GmbH
Original Assignee
Poligrat GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Poligrat GmbH filed Critical Poligrat GmbH
Publication of EP1664391A1 publication Critical patent/EP1664391A1/en
Application granted granted Critical
Publication of EP1664391B1 publication Critical patent/EP1664391B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25F—PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR
    • C25F3/00—Electrolytic etching or polishing
    • C25F3/16—Polishing
    • C25F3/18—Polishing of light metals

Definitions

  • a variety of methods for electropolishing aluminum and aluminum-magnesium alloys are known. These are usually alloys that are formed by rolling, pressing or forging. A good gloss is achieved on the surfaces of these alloys by electropolishing if the silicon content is below approximately 3%. If the silicon content is higher, this is present as a separate phase in the structure of the alloy. Since silicon is not attacked by conventional electropolishing processes, the aluminum is selectively removed during electropolishing and the silicon remains on the surface. As a result, the surfaces do not become smooth and shiny during electropolishing, but rough and dark gray, whereby the silicon can be partially wiped off as a black coating.
  • Chromic acid is just like other compounds of hexavalent chromium classified as very toxic, carcinogenic and fruit-damaging.
  • EP 1 270 761 discloses a method for cleaning light metal alloy surfaces, in which a solution is used which contains phosphoric acid and an alcohol.
  • a solution which contains phosphoric acid and an alcohol.
  • this document also describes a cleaning process in which a solution is used which additionally contains fluoride ions.
  • the fluoride ions serve the purpose of passivating the surface with a fluoride layer in the proposed anodic cleaning.
  • no electropolishing is achieved, since work is carried out in the presence of considerable amounts of alcohol and on the other hand at considerably lower current densities (10 to 500 A / m 2 ). The result is a rough surface (probably through the passivation layer). Substantial material removal as in the case of electropolishing is neither sought nor observed with this process.
  • the present invention has therefore set itself the goal of specifying an electropolishing process which makes it possible to electrochemically polish and deburr light metal alloys, in particular aluminum and aluminum-magnesium alloys with a silicon content of greater than 3%, with good results.
  • the silicon content of such alloys is usually between 6 and 20%.
  • the inventors have observed that the electrochemical dissolution behavior of aluminum and magnesium on the one hand and silicon on the other is very different. Based on this observation, they have set themselves the goal of developing an electrolyte in which the rate of removal of both components is adjusted so that a homogeneous and smooth surface can ultimately be obtained. In addition, it was desirable to obtain an electrolyte in which one can do without environmentally harmful chemicals such as chromic acid or nitric acid (due to the NO x development).
  • the present invention solves the aforementioned problems by providing an electrolyte which essentially contains iron (III) ions in addition to phosphoric acid and a fluoride compound.
  • the fluoride compound can be an alkali fluoride, ammonium fluoride or hydrogen fluoride. Ammonium hydrogen bifluoride has proven to be particularly suitable.
  • the iron (III) ions surprisingly act at least as well as an inhibitor as chromic acid or other chromates and are not harmful to health or the environment.
  • the iron (III) ion content of 0.1 to 8% by weight therefore enables the surface of aluminum and aluminum-silicon compounds to be added in an electrolyte based on phosphoric acid or phosphoric acid-sulfuric acid without the addition of chromic acid or nitric acid. Polishing mixtures to a glossy finish without the electrolyte temporarily attacking and etching the electrolyte chemically.
  • a preferred electrolyte comprises phosphoric acid, sulfuric acid, iron (III) ions, ammonium hydrogen bifluoride (NH 4 HF 2 ) in addition to conventional inhibitors and brighteners.
  • the phosphoric acid (85%) is used in an amount of 20 to 90% by weight, preferably 40 to 60% by weight.
  • the sulfuric acid (86%) is used in an amount of 0 to 80% by weight, preferably between 30 to 50% by weight.
  • the fluoride compound is used in an amount of 0.5 to 6% by weight, preferably between 2 to 4% by weight.
  • the iron (III) ions are used in an amount of 0.1 to 8% by weight, preferably 2 to 3.5% by weight.
  • Alkanolamines such as, for. B. ethanolamine, triisopropanolamine, diethanolamine in an amount of 1-10 wt .-%, preferably between 4-6 wt .-%. Mixtures of different brighteners e.g. various alkanolamines are also possible.
  • the iron (III) ions used as an inhibitor can be in the form of iron (III) citrate, iron (III) sodium cyanate, iron (III) phosphate, iron (III) sulfate, iron (III) oxide in one Amount of 0.1-8 wt .-%, preferably 2-3 wt .-% (based on the ratio Fe / electrolyte) can be used.
  • Mixtures of different inhibitors e.g. Mixtures to use different iron (III) salts.
  • the various constituents of the electrolyte in addition to the acid or the acids and the fluoride, are adjusted overall so that a smooth surface is obtained when the process according to the invention is carried out.
  • other inhibitors can also be added.
  • Brighteners may also be required, such as the amines ethanolamine, diethanolamine and / or triisopylamine mentioned here.
  • the removal of the aluminum and the silicon should finally take place to the same extent.
  • the inventors without this explanation in any way restricting the present invention, assume that with the aid of the electrolyte according to the invention the electrochemical removal of the aluminum on the one hand and the chemical erosion of the silicon on the other hand are kept in a kind of equilibrium.
  • the fluoride used may play a decisive role in controlling the chemical removal of the silicon.
  • the present invention further relates to a method for electropolishing light metal alloy surfaces with a silicon content of more than 3% by weight in an electrolyte which essentially contains phosphoric acid, the surface being switched anodically and the electrolyte containing a fluoride.
  • the process is usually operated at a current density of 5-20 A / dm 2 .
  • the method includes degreasing the alloy parts to be machined. Any commercially available degreasing solution can be used for this.
  • the workpiece to be polished is usually rinsed off with a solvent (for example water) and then immersed in the electropolishing bath and anodically connected to the circuit.
  • the processing time is usually between one and 30 minutes.
  • the current density used is between 5-20 A / dm 2 at a voltage between 5 and 30 volts.
  • the electropolishing is carried out at a temperature of 40 to 90 ° C.
  • the workpiece is removed from the electrolyte and usually rinsed with a solvent (for example water) and then dried.
  • Castings made of material AIMg2Si8 were electropolished in a conventional electropolishing electrolyte (comparative example) and in an electrolyte according to the present invention (example 1).
  • the parts were degreased beforehand by dipping in a commercially available degreasing solution for a period of 5 minutes, then rinsed with water, immersed in the electropolishing bath and anodically connected to the circuit.
  • the processing time was a uniform 12 minutes. After electropolishing, the parts were rinsed with water and dried.
  • Electrolyte consisting of 80.0% by weight phosphoric acid (85%), 8.0% by weight sulfuric acid (96%), 7.0% by weight chromic acid, the rest water. Processing parameters:
  • the surface After electropolishing, the surface showed a black-gray coating that can be partially wiped off. The surface has not been smoothed and leveled.
  • Electrolyte consisting of 49% by weight phosphoric acid (85%), 38% by weight sulfuric acid (96%), 2.5% by weight iron (III) ions from iron (III) citrate, 5% by weight triisopropanolamine, 3% by weight ammonium hydrogen bifluoride, the rest water.
  • the surface was shiny metallic after electropolishing. Due to the silicon content in the alloy, the gloss was slightly weaker and the color slightly darker compared to alloys with a silicon content of less than 2%. The surface was clean and had no wipeable residue.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • ing And Chemical Polishing (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Disintegrating Or Milling (AREA)

Abstract

The invention relates to a method for electropolishing light metal alloy surfaces containing a portion of silicon greater than 3 wt. % in an electrolyte which essentially contains phosphoric acid. The surface is anodically connected and the electrolyte contains a fluoride and iron (III) ions. The invention also relates to an electrolyte used for carrying out said method.

Description

Elektropolierverfahren Electropolishing process
Es sind eine Vielzahl von Verfahren zum Elektropolieren von Aluminium und Aluminium-Magnesium-Legierungen bekannt. Hierbei handelt es sich in der Regel um Legierungen, die durch Walzen, Pressen oder Schmieden umgeformt werden. Durch Elektropolieren wird auf den Oberflächen dieser Legierungen ein guter Glanz erzielt, wenn der Gehalt an Silizium unter ca. 3 % liegt. Bei einem höheren Gehalt an Silizi- um liegt dieses im Gefüge der Legierung als eigene Phase vor. Da Silizium durch herkömmliche Elektropolierverfahren nicht angegriffen wird, wird das Aluminium beim Elektropolieren selektiv abgetragen und das Silizium bleibt auf der Oberfläche stehen. Die Oberflächen werden dadurch während des Elektropolierens nicht glatt und glänzend, sondern rau und dunkelgrau, wobei das Silizium teilweise als schwärzlicher Belag abgewischt werden kann.A variety of methods for electropolishing aluminum and aluminum-magnesium alloys are known. These are usually alloys that are formed by rolling, pressing or forging. A good gloss is achieved on the surfaces of these alloys by electropolishing if the silicon content is below approximately 3%. If the silicon content is higher, this is present as a separate phase in the structure of the alloy. Since silicon is not attacked by conventional electropolishing processes, the aluminum is selectively removed during electropolishing and the silicon remains on the surface. As a result, the surfaces do not become smooth and shiny during electropolishing, but rough and dark gray, whereby the silicon can be partially wiped off as a black coating.
Herkömmliche Elektropolierverfahren verwenden zumeist Elektrolyten auf der Basis von Phosphorsäure-Schwefelsäure-Chromsäure-Gemischen, Phosphorsäure- Chromsäure-Gemischen, Phosphorsäure-Schwefelsäure-Gemischen sowie Phosphor- säure-Salpetersäure-Gemischen. All diesen Elektrolyten ist gemeinsam, dass befriedigende Ergebnisse hinsichtlich Glanz und Glätte nur auf Werkstoffen mit einem Siliziumgehalt unter 3 % erzielbar sind.Conventional electropolishing processes mostly use electrolytes based on phosphoric acid-sulfuric acid-chromic acid mixtures, phosphoric acid-chromic acid mixtures, phosphoric acid-sulfuric acid mixtures and phosphoric acid-nitric acid mixtures. All these electrolytes have in common that satisfactory results with regard to gloss and smoothness can only be achieved on materials with a silicon content below 3%.
Die Industrie nutzt zunehmend Gießverfahren als einfaches, materialsparendes und wirtschaftliches Verfahren zur Herstellung komplex geformter Serienteile. Die zum Giessen verwendeten Legierungen weisen jedoch durchwegs einen Siliziumanteil in der Legierung von deutlich über 3 % auf, um das für die Gießverfahren erforderliche Schmelz- und Fließverhalten zu erzielen. Diese Legierungen gelten deshalb bisher als nicht geeignet für die Bearbeitung durch Elektropolieren. Lediglich das Elektropolier- verfahren gemäß SU 817104 A auf Basis von Phosphorsäure, Chromsäure und Amo- niumbifluorid bezieht sich auf Aluminium-Silizium-Legierungen mit höherem Siliziumgehalt. In diesem Elektrolyten wirkt Chromsäure als Inhibitor, um einen chemischen Angriff des Elektrolyten auf die elektropolierte Oberfläche zu unterbinden. Dieser Angriff würde die Wirkung der Elektropolitur sofort wieder zerstören, da die Aluminiumoberfläche ohne den Inhibitor gegen den Angriff der Säuremischung nicht ausreichend beständig ist, um die Zeitspanne zwischen Abschalten des Stromes und Abspülen des Elektrolyten unbeschädigt zu überstehen. Chromsäure ist ebenso wie andere Verbindungen des sechswertigen Chroms als sehr giftig, krebserregend und fruchtschädigend eingestuft.The industry is increasingly using casting processes as a simple, material-saving and economical process for the production of complex shaped series parts. However, the alloys used for casting consistently have a silicon content in the alloy of well over 3% in order to achieve the melting and flow behavior required for the casting process. These alloys are therefore not considered suitable for processing by electropolishing. Only the electropolishing process according to SU 817104 A based on phosphoric acid, chromic acid and ammonium bifluoride refers to aluminum-silicon alloys with a higher silicon content. In this electrolyte, chromic acid acts as an inhibitor to prevent chemical attack by the electrolyte on the electropolished surface. This attack would immediately destroy the effect of the electropolishing, since the aluminum surface without the inhibitor is not sufficiently resistant to the attack of the acid mixture in order to survive the time between switching off the current and rinsing off the electrolyte without damage. Chromic acid is just like other compounds of hexavalent chromium classified as very toxic, carcinogenic and fruit-damaging.
Aus der EP 1 270 761 ist ein Verfahren zum Reinigen von Leichtmetalllegierungs- Oberflächen bekannt, bei dem mit einer Lösung gearbeitet wird, welche Phosphorsäure und einen Alkohol enthält. Unter anderem beschreibt dieses Dokument auch ein Reinigungsverfahren, bei dem eine Lösung eingesetzt wird, die zusätzlich Fluorid- Ionen enthält. Die Fluorid-Ionen dienen dem Zweck, bei der vorgeschlagenen anodischen Reinigung die Oberfläche durch eine Fluoridschicht zu passivieren. Mit diesem Verfahren nach dem Stand der Technik wird aber keine Elektropolitur erreicht, da einmal in Gegenwart beträchtlicher Mengen Alkohol und zum anderen bei erheblich geringeren Stromdichten gearbeitet wird (10 bis 500 A/m2). Im Ergebnis wird also eine raue Oberfläche erhalten (wohl durch die Passivierungsschicht). Ein substantieller Materialabtrag wie im Falle einer Elektropolitur wird bei diesem Verfahren weder angestrebt noch beobachtet.EP 1 270 761 discloses a method for cleaning light metal alloy surfaces, in which a solution is used which contains phosphoric acid and an alcohol. Among other things, this document also describes a cleaning process in which a solution is used which additionally contains fluoride ions. The fluoride ions serve the purpose of passivating the surface with a fluoride layer in the proposed anodic cleaning. With this prior art method, however, no electropolishing is achieved, since work is carried out in the presence of considerable amounts of alcohol and on the other hand at considerably lower current densities (10 to 500 A / m 2 ). The result is a rough surface (probably through the passivation layer). Substantial material removal as in the case of electropolishing is neither sought nor observed with this process.
Die vorliegende Erfindung hat sich somit zum Ziel gesetzt, ein Elektropolierverfahren anzugeben, das es ermöglicht, Leichtmetalllegierungen, insbesondere Aluminium- und Aluminium-Magnesium-Legierungen mit einem Siliziumgehalt von größer als 3 %, mit gutem Ergebnis elektrochemisch zu polieren und zu entgraten. Der Siliziumgehalt solcher Legierungen liegt üblicherweise zwischen 6 und 20 %.The present invention has therefore set itself the goal of specifying an electropolishing process which makes it possible to electrochemically polish and deburr light metal alloys, in particular aluminum and aluminum-magnesium alloys with a silicon content of greater than 3%, with good results. The silicon content of such alloys is usually between 6 and 20%.
Die Erfinder haben beobachtet, dass sich das elektrochemische Auflösungsverhalten von Aluminium und Magnesium einerseits und Silizium andererseits stark unterschei- det. Auf der Grundlage dieser Beobachtung haben sie sich zum Ziel gesetzt, einen Elektrolyten zu entwickeln, bei dem die Abtragungsgeschwindigkeit beider Komponenten so angeglichen wird, dass schließlich eine homogene und glatte Oberfläche erhalten werden kann. Zusätzlich war wünschenswert einen Elektrolyten zu erhalten, bei dem man auf umweltschädliche Chemikalien wie Chromsäure oder Salpetersäure (aufgrund der NOx-Entwicklung) verzichten kann.The inventors have observed that the electrochemical dissolution behavior of aluminum and magnesium on the one hand and silicon on the other is very different. Based on this observation, they have set themselves the goal of developing an electrolyte in which the rate of removal of both components is adjusted so that a homogeneous and smooth surface can ultimately be obtained. In addition, it was desirable to obtain an electrolyte in which one can do without environmentally harmful chemicals such as chromic acid or nitric acid (due to the NO x development).
Die vorliegende Erfindung löst die vorstehend genannten Probleme durch die Bereitstellung eines Elektrolyten, der im wesentlichen neben Phosphorsäure und einer Flu- oridverbindung, Eisen(III)-Ionen enthält. Die Fluoridverbindung kann ein Alkalifluorid, Ammoniumfluorid oder Hydrogenfluorid sein. Als besonders geeignet hat sich Ammoniumhydrogenbifluorid erwiesen. Die Eisen(III)-Ionen wirken überraschend mindestens ebenso gut als Inhibitor wie Chromsäure oder andere Chromate und sind nicht gesundheits- oder umweltschädigend. Der Eisen(III)-Ionengehalt von 0,1 bis 8 Gew.-% ermöglicht es daher, die Oberfläche von Aluminium- und Aluminium-Silizium-Verbindungen ohne Zusatz von Chromsäure oder Salpetersäure in einem Elektrolyten auf Basis von Phosphorsäure oder Phosphorsäure-Schwefelsäure- Gemischen glänzend zu polieren, ohne dass die elektropolierte Oberfläche durch den Elektrolyten kurzfristig chemisch angegriffen und verätzt wird.The present invention solves the aforementioned problems by providing an electrolyte which essentially contains iron (III) ions in addition to phosphoric acid and a fluoride compound. The fluoride compound can be an alkali fluoride, ammonium fluoride or hydrogen fluoride. Ammonium hydrogen bifluoride has proven to be particularly suitable. The iron (III) ions surprisingly act at least as well as an inhibitor as chromic acid or other chromates and are not harmful to health or the environment. The iron (III) ion content of 0.1 to 8% by weight therefore enables the surface of aluminum and aluminum-silicon compounds to be added in an electrolyte based on phosphoric acid or phosphoric acid-sulfuric acid without the addition of chromic acid or nitric acid. Polishing mixtures to a glossy finish without the electrolyte temporarily attacking and etching the electrolyte chemically.
Ein bevorzugter Elektrolyt umfasst Phosphorsäure, Schwefelsäure, Eisen(III)-Ionen, Ammoniumhydrogenbifluorid (NH4HF2) neben üblichen Inhibitoren und Glanzbild- nern. Die Phosphorsäure (85 %-ig) wird dabei in einer Menge von 20 bis 90 Gew.-%, bevorzugt von 40 bis 60 Gew.-% eingesetzt. Die Schwefelsäure (86 %-ig) wird in einer Menge von 0 bis 80 Gew.-%, bevorzugt zwischen 30 bis 50 Gew.-% eingesetzt. Die Fluoridverbindung wird in einer Menge von 0,5 bis 6 Gew.-%, bevorzugt zwischen 2 bis 4 Gew.-% eingesetzt. Die Eisen(III)-Ionen werden in einer Menge von 0,1 bis 8 Gew.%, vorzugsweise 2 bis 3,5 Gew.% eingesetzt.A preferred electrolyte comprises phosphoric acid, sulfuric acid, iron (III) ions, ammonium hydrogen bifluoride (NH 4 HF 2 ) in addition to conventional inhibitors and brighteners. The phosphoric acid (85%) is used in an amount of 20 to 90% by weight, preferably 40 to 60% by weight. The sulfuric acid (86%) is used in an amount of 0 to 80% by weight, preferably between 30 to 50% by weight. The fluoride compound is used in an amount of 0.5 to 6% by weight, preferably between 2 to 4% by weight. The iron (III) ions are used in an amount of 0.1 to 8% by weight, preferably 2 to 3.5% by weight.
Als Glanzbildner werden Alkanolamine wie z. B. Ethanolamin, Triisopropanolamin, Diethanolamin in einer Menge von 1-10 Gew.-%, bevorzugt zwischen 4-6 Gew.-% eingesetzt. Mischungen verschiedener Glanzbildner z.B. verschiedene Alkanolamine sind ebenfalls möglich.Alkanolamines such as, for. B. ethanolamine, triisopropanolamine, diethanolamine in an amount of 1-10 wt .-%, preferably between 4-6 wt .-%. Mixtures of different brighteners e.g. various alkanolamines are also possible.
Die als Inhibitor verwendeten Eisen(III)-ionen können in Form von Eisen(III)-citrat, Eisen(III)-natriumcyanat, Eisen(III)-phosphat, Eisen(III)-sulfat, Eisen(III)-oxid in einer Menge von 0,1-8 Gew.-%, bevorzugt von 2-3 Gew.-% (bezogen auf das Ver- hältnis Fe / Elektrolyt), eingesetzt werden. Es ist möglich Mischungen verschiedener Inhibitoren z.B. Mischungen verschiedene Eisen(III)-Salze einzusetzen.The iron (III) ions used as an inhibitor can be in the form of iron (III) citrate, iron (III) sodium cyanate, iron (III) phosphate, iron (III) sulfate, iron (III) oxide in one Amount of 0.1-8 wt .-%, preferably 2-3 wt .-% (based on the ratio Fe / electrolyte) can be used. Mixtures of different inhibitors e.g. Mixtures to use different iron (III) salts.
Die verschiedenen Bestandteile des Elektrolyten neben der Säure bzw. den Säuren und dem Fluorid werden insgesamt so eingestellt, dass bei Durchführung des erfin- dungsgemäßen Verfahrens eine glatte Oberfläche erhalten wird. Dabei können auch weitere Inhibitoren neben den Eisen(III)-verbindungen zugesetzt werden Gegebenenfalls sind auch Glanzbildner erforderlich, wie die hier genannten Amine Ethanolamin, Diethanolamin und/oder Triisopylamin. Bei dem erfindungsgemäßen Verfahren soll schließlich der Abtrag des Aluminiums sowie des Siliziums im gleichen Maße er- folgen. Die Erfinder, ohne dass diese Erläuterung in irgendeiner Weise die vorliegende Erfindung beschränken sollte, gehen davon aus, dass mit Hilfe des erfindungsgemäßen Elektrolyten der elektrochemische Abtrag des Aluminiums einer- seits und der chemische Abtrag des Siliziums andererseits in einer Art Gleichgewicht gehalten werden. Neben der eingesetzten Säure (im wesentlichen Phosphorsäure) spielt möglicherweise das eingesetzte Fluorid eine entscheidende Rolle bei der Steuerung des chemischen Abtrags des Siliziums.The various constituents of the electrolyte, in addition to the acid or the acids and the fluoride, are adjusted overall so that a smooth surface is obtained when the process according to the invention is carried out. In addition to the iron (III) compounds, other inhibitors can also be added. Brighteners may also be required, such as the amines ethanolamine, diethanolamine and / or triisopylamine mentioned here. In the process according to the invention, the removal of the aluminum and the silicon should finally take place to the same extent. The inventors, without this explanation in any way restricting the present invention, assume that with the aid of the electrolyte according to the invention the electrochemical removal of the aluminum on the one hand and the chemical erosion of the silicon on the other hand are kept in a kind of equilibrium. In addition to the acid used (essentially phosphoric acid), the fluoride used may play a decisive role in controlling the chemical removal of the silicon.
Die vorliegende Erfindung betrifft weiterhin ein Verfahren zum Elektropolieren von Leichtmetalllegierungsoberflächen mit einem Siliziumanteil von mehr als 3 Gew.-% in einem Elektrolyten, der im wesentlichen Phosphorsäure enthält, wobei die Oberfläche anodisch geschaltet wird und der Elektrolyt ein Fluorid enthält. Das Verfahren wird üblicherweise bei einer Stromdichte von 5-20 A/dm2 betrieben.The present invention further relates to a method for electropolishing light metal alloy surfaces with a silicon content of more than 3% by weight in an electrolyte which essentially contains phosphoric acid, the surface being switched anodically and the electrolyte containing a fluoride. The process is usually operated at a current density of 5-20 A / dm 2 .
Das Verfahren umfasst als ersten optionalen Schritt das Entfetten der zu bearbeitenden Legierungsteile. Hierzu kann jede handelsübliche Entfettungslösung verwendet werden. Üblicherweise wird das zu polierende Werkstück mit einem Lösungsmittel (z.B. Wasser) abgespült, und anschließend in das Elektropolierbad getaucht und anodisch mit dem Stromkreis verbunden. Gewöhnlich beträgt die Bearbeitungszeit zwischen einer und 30 Minuten. Die verwendete Stromdichte liegt zwischen 5-20 A/dm2 bei einer Spannung zwischen 5 und 30 Volt. Die Elektropolitur wird bei einer Temperatur von 40 bis 90 °C durchgeführt. Als abschließender Schritt wird das Werkstück aus dem Elektrolyten entnommen und üblicherweise mit einem Lösungsmittel (z.B. Wasser) gespült und anschließend getrocknet.As a first optional step, the method includes degreasing the alloy parts to be machined. Any commercially available degreasing solution can be used for this. The workpiece to be polished is usually rinsed off with a solvent (for example water) and then immersed in the electropolishing bath and anodically connected to the circuit. The processing time is usually between one and 30 minutes. The current density used is between 5-20 A / dm 2 at a voltage between 5 and 30 volts. The electropolishing is carried out at a temperature of 40 to 90 ° C. As a final step, the workpiece is removed from the electrolyte and usually rinsed with a solvent (for example water) and then dried.
BeispieleExamples
Gussteile aus Werkstoff AIMg2Si8 wurden in einem herkömmlichen Elektropolierelekt- rolyten (Vergleichsbeispiel) und in einem Elektrolyten gemäß der vorliegenden Erfindung (Beispiel 1) elektropoliert. In beiden Fällen wurden die Teile zuvor entfettet durch Tauchen in einer handelsüblichen Entfettungslösung für die Dauer von 5 Minu- ten, anschließend mit Wasser abgespült, in das Elektropolierbad getaucht und anodisch mit dem Stromkreis verbunden. Die Bearbeitungszeit betrug einheitlich 12 Minuten. Nach dem Elektropolieren wurden die Teile mit Wasser abgespült und getrocknet.Castings made of material AIMg2Si8 were electropolished in a conventional electropolishing electrolyte (comparative example) and in an electrolyte according to the present invention (example 1). In both cases, the parts were degreased beforehand by dipping in a commercially available degreasing solution for a period of 5 minutes, then rinsed with water, immersed in the electropolishing bath and anodically connected to the circuit. The processing time was a uniform 12 minutes. After electropolishing, the parts were rinsed with water and dried.
VergleichsbeispielComparative example
Elektrolyt bestehend aus 80,0 Gew.-% Phosphorsäure (85 %-ig), 8,0 Gew.-% Schwefelsäure (96 %-ig), 7,0 Gew.-% Chromsäure, Rest Wasser. Bearbeitungsparameter:Electrolyte consisting of 80.0% by weight phosphoric acid (85%), 8.0% by weight sulfuric acid (96%), 7.0% by weight chromic acid, the rest water. Processing parameters:
Spannung: 18 V Temperatur: 70°CVoltage: 18 V temperature: 70 ° C
Stromdichte: 10 A/dm2 Current density: 10 A / dm 2
Die Oberfläche zeigte nach dem Elektropolieren einen schwarzgrauen Belag, der sich teilweise abwischen lässt. Es ist keine Glättung und Einebnung der Oberfläche er- folgt.After electropolishing, the surface showed a black-gray coating that can be partially wiped off. The surface has not been smoothed and leveled.
Beispiel 1:Example 1:
Elektrolyt bestehend aus 49 Gew.-% Phosphorsäure (85 %-ig), 38 Gew.-% Schwefelsäure (96 %-ig), 2,5 Gew.-% Eisen(III)-ionen aus Eisen(III)-citrat, 5 Gew.-% Trii- sopropanolamin, 3 Gew.-% Ammoniumhydrogenbifluorid, Rest Wasser.Electrolyte consisting of 49% by weight phosphoric acid (85%), 38% by weight sulfuric acid (96%), 2.5% by weight iron (III) ions from iron (III) citrate, 5% by weight triisopropanolamine, 3% by weight ammonium hydrogen bifluoride, the rest water.
Bearbeitungsparameter:Processing parameters:
Spannung: 18 V Temperatur: 65°CVoltage: 18 V temperature: 65 ° C
Stromdichte: 10 A/dm2 Current density: 10 A / dm 2
Die Oberfläche war nach dem Elektropolieren metallisch glänzend. Bedingt durch den Siliziumanteil in der Legierung war der Glanz geringfügig schwächer und die Farbe etwas dunkler im Vergleich zu Legierungen mit einem Siliziumgehalt unter 2 %. Die Oberfläche war metallisch sauber und wies keine abwischbaren Rückstände auf.The surface was shiny metallic after electropolishing. Due to the silicon content in the alloy, the gloss was slightly weaker and the color slightly darker compared to alloys with a silicon content of less than 2%. The surface was clean and had no wipeable residue.
958889 958889

Claims

Ansprüche Expectations
1. Verfahren zum Elektropolieren von Leichtmetalllegierungsoberflächen mit ei- nem Siliziumanteil von mehr als 3 Gew.-% in einem Elektrolyten der im wesentlichen Phosphorsäure oder ein Phosphorsäure-Schwefelsäure-Gemisch sowie ein Fluorid enthält, wobei die Oberfläche anodisch geschaltet wird und der Elektrolyt Eisen(III)- Ionen enthält.1. Method for electropolishing light metal alloy surfaces with a silicon content of more than 3% by weight in an electrolyte which essentially contains phosphoric acid or a phosphoric acid-sulfuric acid mixture and a fluoride, the surface being switched anodically and the electrolyte iron ( III) - contains ions.
2. Verfahren gemäß Anspruch 1, bei dem mit einer Stromdichte von 5 bis 20 A/dm2 gearbeitet wird.2. The method according to claim 1, in which a current density of 5 to 20 A / dm 2 is used.
3. Elektrolyt zur Durchführung eines Verfahrens nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Elektrolyt3. electrolyte for performing a method according to claim 1 or 2, characterized in that the electrolyte
Phosphorsäure in einer Menge von 20 bis 90 Gew.-%, Schwefelsäure in einer Menge von 0 bis 80 Gew.-%, - eine Fluoridverbindung in einer Menge von 0,5 bis 6 Gew.-%, und Eisen(III)-Ionen in einer Menge von 0,1 bis 8 Gew.-% umfasst.Phosphoric acid in an amount of 20 to 90% by weight, sulfuric acid in an amount of 0 to 80% by weight, a fluoride compound in an amount of 0.5 to 6% by weight, and iron (III) ions in an amount of 0.1 to 8% by weight.
4. Elektrolyt nach Anspruch 3, dadurch gekennzeichnet, dass dieser zusätzlich Glanzbildner enthält.4. Electrolyte according to claim 3, characterized in that it additionally contains brighteners.
5. Elektrolyt gemäß Anspruch 4, dadurch gekennzeichnet, dass der Glanzbildner ein Ethanolamin, Diethanolamin und/oder Triisopropylamin ist und in einer Menge von 1 bis 10 Gew.-% vorliegt. 5. Electrolyte according to claim 4, characterized in that the brightener is an ethanolamine, diethanolamine and / or triisopropylamine and is present in an amount of 1 to 10 wt .-%.
EP04764662A 2003-09-05 2004-08-31 Electropolishing method Expired - Lifetime EP1664391B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10341061A DE10341061B4 (en) 2003-09-05 2003-09-05 Electropolishing process for light metal alloys and electrolyte
PCT/EP2004/009697 WO2005024099A1 (en) 2003-09-05 2004-08-31 Electropolishing method

Publications (2)

Publication Number Publication Date
EP1664391A1 true EP1664391A1 (en) 2006-06-07
EP1664391B1 EP1664391B1 (en) 2010-05-05

Family

ID=34223395

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04764662A Expired - Lifetime EP1664391B1 (en) 2003-09-05 2004-08-31 Electropolishing method

Country Status (5)

Country Link
EP (1) EP1664391B1 (en)
AT (1) ATE466976T1 (en)
DE (2) DE10341061B4 (en)
ES (1) ES2344143T3 (en)
WO (1) WO2005024099A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104032365A (en) * 2014-06-19 2014-09-10 南昌航空大学 Formula and process aiming at electrolytic polishing of siliceous aluminum alloy
CN104032364A (en) * 2014-06-19 2014-09-10 南昌航空大学 Formula and process aiming at phosphoric-acid-free electrolytic polishing of siliceous aluminum alloy

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9504554B2 (en) * 2013-01-16 2016-11-29 Biotronik Ag Microstructured absorbable implant
US11590261B2 (en) 2014-04-02 2023-02-28 Biotronik Ag Method for the preparation of biological tissue for dry use in an implant
EP2926840B1 (en) 2014-04-02 2018-05-09 Biotronik AG Method for the treatment of biological tissue for dry use in an implant
CN104032363A (en) * 2014-06-19 2014-09-10 南昌航空大学 Phosphoric-acid-free electrochemical polishing process for siliceous aluminum alloy
DE102015118789A1 (en) 2015-11-03 2017-05-04 Biotronik Ag Method for reducing paravalvular leakage with decellularized tissue
US11737867B2 (en) 2015-11-03 2023-08-29 Biotronik Ag Method for reducing paravalvular leaks with decellularized tissue
EP3269848B1 (en) * 2016-07-13 2019-09-11 Airbus Defence and Space GmbH A method for the surface finishing of metals and alloys
CN106757298B (en) * 2016-12-21 2019-08-02 江苏和兴汽车科技有限公司 A kind of Chrome-free electropolishing liquid, aluminium alloy electric polishing method and automobile aluminum decoration

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE29949C (en) * B. drechsler in Ernstthal in Sachsen, Chemnitzer Strafse Method of engaging the thumb fingers in gloves
US3776827A (en) * 1966-12-01 1973-12-04 K Inoue Method of deburring workpieces
SU817104A1 (en) * 1979-01-04 1981-03-30 Физико-Технический Институт Ан Белорусскойсср Solution for electrochemical polishing of aluminium containing materials
DE4237021C1 (en) * 1992-11-02 1994-02-10 Poligrat Gmbh Means for pickling the surface of chromium-nickel steels and chrome steels and use of the agent
DE9214890U1 (en) * 1992-11-02 1993-01-07 Poligrat GmbH, 8000 München Agents for pickling and/or cleaning metal surfaces
US5271804A (en) * 1992-11-03 1993-12-21 Elf Atochem North America, Inc. Etchant/deoxidizer for aluminum
SE504733C2 (en) * 1994-06-17 1997-04-14 Ta Chemistry Ab Pickling procedure
US6407047B1 (en) * 2000-02-16 2002-06-18 Atotech Deutschland Gmbh Composition for desmutting aluminum

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2005024099A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104032365A (en) * 2014-06-19 2014-09-10 南昌航空大学 Formula and process aiming at electrolytic polishing of siliceous aluminum alloy
CN104032364A (en) * 2014-06-19 2014-09-10 南昌航空大学 Formula and process aiming at phosphoric-acid-free electrolytic polishing of siliceous aluminum alloy

Also Published As

Publication number Publication date
ES2344143T3 (en) 2010-08-19
ATE466976T1 (en) 2010-05-15
DE10341061B4 (en) 2007-08-02
DE10341061A1 (en) 2005-03-31
EP1664391B1 (en) 2010-05-05
DE502004011138D1 (en) 2010-06-17
WO2005024099A1 (en) 2005-03-17

Similar Documents

Publication Publication Date Title
DE69612469T2 (en) Process for the treatment of aluminum alloys
DE3118375C2 (en)
EP0249650B1 (en) Electrolyte for electrochemically polishing metal surfaces
EP1923490B1 (en) Electropolishing method
EP1664391B1 (en) Electropolishing method
DE10393234T5 (en) Surface treatment of magnesium and its alloys
EP1911862B1 (en) Electropolishing method for niobium and tantalum
DE3020012C2 (en) Method of exposing the silicon crystals on the surface of a body made of an aluminum alloy with a high silicon content
DE3706711A1 (en) METHOD FOR CLEANING SURFACES OF AN ALUMINUM OBJECT
DE3318598A1 (en) BATH AND METHOD FOR THE ELECTROLYTIC REMOVAL OF COATS FROM COPPER, COPPER ALLOY OR CHROME FROM A FERROUS BASE METAL
EP3201281B1 (en) Method for the wet chemical polishing and deburring of moulded parts made of zinc
DE102005055768A1 (en) Method and means for the electrolytic cleaning and descaling of a metallic workpiece
EP1913181B1 (en) Electropolishing method
EP0201841B1 (en) Process for phosphating metal surfaces
DE2729423C2 (en)
DE60216291T2 (en) SURFACE TREATMENT AGENT AND METHOD FOR REMOVING THE SI COMPONENTS AND REDUCED METAL SALTS WHICH APPEAR WHEN ESTABLISHING ALUMINUM PRESSURE CAST IRONS
DE3701728A1 (en) METHOD FOR APPLYING OXALATUE COATINGS ON STAINLESS STEEL
EP0127774B1 (en) Process for protecting anodised aluminium
EP0224190A2 (en) Process for activating metallic surfaces prior to zinc phosphating
DE10156624B4 (en) Method and pickling solution for cleaning deposits of a steel workpiece
DE3217145A1 (en) Method for cleaning, degreasing and activating metal surfaces
DE3705633A1 (en) METHOD FOR PREPARING WORKPIECES FROM ALUMINUM OR ITS ALLOYS FOR PAINTING
DE19924589A1 (en) Hard material layers stripping from hard metal substrates, e.g. tool and machine component scrap, involves using a solution of an oxidizing mineral acid and a hydrogen halide compound
EP0636710B1 (en) Method for cleaning articles
DE763172C (en) Process for the production of smooth and shiny surfaces on objects made of aluminum and aluminum alloys

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20060112

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

DAX Request for extension of the european patent (deleted)
GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: GERMAN

REF Corresponds to:

Ref document number: 502004011138

Country of ref document: DE

Date of ref document: 20100617

Kind code of ref document: P

REG Reference to a national code

Ref country code: NL

Ref legal event code: VDEP

Effective date: 20100505

REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2344143

Country of ref document: ES

Kind code of ref document: T3

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

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100806

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100906

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

REG Reference to a national code

Ref country code: HU

Ref legal event code: AG4A

Ref document number: E009131

Country of ref document: HU

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

Ref country code: MC

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

Effective date: 20100831

26N No opposition filed

Effective date: 20110208

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 502004011138

Country of ref document: DE

Effective date: 20110207

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

Ref country code: BE

Payment date: 20110822

Year of fee payment: 8

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

Ref country code: LU

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

Effective date: 20100831

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

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

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100505

BERE Be: lapsed

Owner name: POLIGRAT G.M.B.H.

Effective date: 20120831

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

Ref country code: BE

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

Effective date: 20120831

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

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20100805

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 13

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 14

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 15

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

Ref country code: GB

Payment date: 20180604

Year of fee payment: 15

Ref country code: FR

Payment date: 20180829

Year of fee payment: 15

Ref country code: ES

Payment date: 20180921

Year of fee payment: 15

Ref country code: IT

Payment date: 20180823

Year of fee payment: 15

Ref country code: IE

Payment date: 20180823

Year of fee payment: 15

Ref country code: DE

Payment date: 20180828

Year of fee payment: 15

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

Ref country code: CZ

Payment date: 20180822

Year of fee payment: 15

Ref country code: HU

Payment date: 20180823

Year of fee payment: 15

Ref country code: AT

Payment date: 20180817

Year of fee payment: 15

Ref country code: CH

Payment date: 20180816

Year of fee payment: 15

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 502004011138

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: MM01

Ref document number: 466976

Country of ref document: AT

Kind code of ref document: T

Effective date: 20190831

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

Effective date: 20190831

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

Ref country code: HU

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

Effective date: 20190901

Ref country code: AT

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

Effective date: 20190831

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

Ref country code: CZ

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

Effective date: 20190831

Ref country code: CH

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

Effective date: 20190831

Ref country code: LI

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

Effective date: 20190831

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: 20190831

Ref country code: IE

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

Effective date: 20190831

Ref country code: DE

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

Effective date: 20200303

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: 20190831

Ref country code: IT

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

Effective date: 20190831

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20210108

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: 20190901