EP0399170A2 - Polishing process - Google Patents

Polishing process Download PDF

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Publication number
EP0399170A2
EP0399170A2 EP90105559A EP90105559A EP0399170A2 EP 0399170 A2 EP0399170 A2 EP 0399170A2 EP 90105559 A EP90105559 A EP 90105559A EP 90105559 A EP90105559 A EP 90105559A EP 0399170 A2 EP0399170 A2 EP 0399170A2
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EP
European Patent Office
Prior art keywords
parts
shining
stage
electrolyte
operating temperature
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.)
Ceased
Application number
EP90105559A
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German (de)
French (fr)
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EP0399170A3 (en
Inventor
Peter Venn
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.)
Johnson Controls Interiors GmbH and Co KG
Original Assignee
Gebrueder Happich 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 Gebrueder Happich GmbH filed Critical Gebrueder Happich GmbH
Publication of EP0399170A2 publication Critical patent/EP0399170A2/en
Publication of EP0399170A3 publication Critical patent/EP0399170A3/en
Ceased legal-status Critical Current

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    • 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
    • C25F3/20—Polishing of light metals of aluminium

Definitions

  • the invention relates to a polishing process for parts made of aluminum or aluminum alloys.
  • Aluminum parts such as aluminum pressed or rolled profiles, are used, among other things, in the building hardware and lighting industry or in particular in motor vehicle construction with, for example, window frame systems or also as decorative frames, finishers and the like. Like. Used. It is also known to use parts made of aluminum or aluminum alloys that have a colored anodized surface. Here, the parts are generally subjected to a gloss treatment as a preliminary step before coloring (both in their own color and in color). A well-known glossy treatment of parts made of aluminum or aluminum alloy is the so-called “Brytal” process (cf. Wernick, Pinner "The surface treatment of aluminum 1969, page 84). However, it has been shown that chemically polished aluminum parts after the The Brytal process disadvantageously forms a glossy structure or orange peel, and this disadvantage also arises when using acidic glossy electrolytes.
  • the present invention is based on the object of demonstrating a glossing process for parts made of aluminum or aluminum alloys, with which an optimal surface reflection or gloss effect of the parts can be generated.
  • a method which, according to the invention, is characterized in that the parts in an alkaline electrolyte of the composition operated by means of direct current: Na3PO4 (trisodium phosphate) 120 g / l NA2CO3 (disodium carbonate) 330 g / l AlPO4 (aluminum phosphate) 10 g / l Extracts from beech wood 5 ml / l be treated at an operating temperature of around 70 - 80 o C.
  • the particular advantage of this process consists in the generation of an optimal surface reflection or gloss effect of aluminum parts (profile strips or the like) for the production of colored and natural-colored, anodically produced anodized layers. This results in another significant advantage, a considerable reduction in reworking due to glossy defects.
  • the parts preferably are subjected in the electrolyte of a 2-stage treatment, the parts vorgeglänzt in the first stage, at an operating temperature of about 80 o C and nachgeglänzt in the second stage, at an operating temperature of about 70 ° C.
  • the electrolyte is therefore operated in two stages, pre-glossing and post-glossing, the two stages containing a similar composition and differing only in the operating temperature.
  • the parts are exposed in the first treatment stage with a current density of approximately 3 A / dm2 and in the second treatment stage with a current density of approximately 1.5-2 A / dm2. Due to the higher operating temperature of the first stage, a higher material removal is achieved with a current density of 3 A / dm2.
  • the parts are exposed for a total of about 18 minutes. It has proven to be particularly advantageous that the voltage applied is interrupted for about 2 to 10 seconds about one minute before the exposure time expires. It is hereby achieved that the gloss film formed during the shining is largely removed without etching the surface.
  • a particularly advantageous development of the invention consists in that the electrolyte is filtered (continuously or discontinuously), that the filter cake formed is rinsed, and that the chemicals recovered in this form are returned to the electrolyte.
  • This measure makes the method according to the invention particularly environmentally friendly, as is also a considerable reduction in costs with regard to landfill charges and direct discharges.
  • the electrolyte can be filtered in particular by means of a chamber filter press.
  • the parts are treated in a cathodically connected container made of structural steel, the parts being used as anodes. It can also be provided that a container equipped with heating and cooling devices is used. Finally, it is advantageous if a container is used which has an overflow leading to a filter station and an inlet coming from the filter station.

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  • 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)
  • Chemical Treatment Of Metals (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)

Abstract

A description is given of a polishing process for aluminium or aluminium-alloy parts, which process is distinguished, in particular, by the fact that the parts are treated with direct current in an electrolyte of the composition:… 120 g/l Na3PO4 (trisodium phosphate),… 330 g/l Na2CO3 (disodium carbonate),… 10 g/l AlPO4 (aluminium phosphate), and… 5 ml/l beechwood extract, at an operating temperature of about 70 - 80 DEG C.

Description

Die Erfindung bezieht sich auf ein Glänzverfahren für Teile aus Alu­minium oder Aluminium-Legierungen.The invention relates to a polishing process for parts made of aluminum or aluminum alloys.

Aluminiumteile, wie Aluminium-Preß- oder Rollprofile, werden u.a. in der Baubeschlegs- und Beleuchtungsindustrie oder insbesondere im Kraftfahrzeugbau bei z.B. Fenstereinfaßsystemen oder auch als Zierrahmen, Zieleisten u. dgl. eingesetzt. Dabei ist es auch bekannt, solche Teile aus Aluminium oder Aluminium-Legierungen zu verwenden, die eine farbig eloxierte Oberfläche aufweisen. Hierbei werden die Teile gewissermaßen als Vorstufe vor dem Einfärben (sowohl in Eigen­farbe als auch gefärbt) in der Regel einer Glänzbehandlung unterzogen. Eine bekannte Glänzbehandlung von Teilen aus Aluminium oder Aluminium-­Legierung ist das sogenannte "Brytal"-Verfahren (vgl. Wernick, Pinner "Die Oberflächenbehandlung von Aluminium 1969, Seite 84). Es hat sich aber gezeigt, daß sich auf chemisch geglänzten Aluminiumteilen nach dem Brytal-Verfahren nachteiligerweise eine Glänzstruktur bzw. Apfelsinenhaut bildet. Dieser Nachteil ergibt sich auch bei Verwen­dung von sauren Glänzelektrolyten.Aluminum parts, such as aluminum pressed or rolled profiles, are used, among other things, in the building hardware and lighting industry or in particular in motor vehicle construction with, for example, window frame systems or also as decorative frames, finishers and the like. Like. Used. It is also known to use parts made of aluminum or aluminum alloys that have a colored anodized surface. Here, the parts are generally subjected to a gloss treatment as a preliminary step before coloring (both in their own color and in color). A well-known glossy treatment of parts made of aluminum or aluminum alloy is the so-called "Brytal" process (cf. Wernick, Pinner "The surface treatment of aluminum 1969, page 84). However, it has been shown that chemically polished aluminum parts after the The Brytal process disadvantageously forms a glossy structure or orange peel, and this disadvantage also arises when using acidic glossy electrolytes.

Der vorliegenden Erfindung liegt nun die Aufgabe zugrunde, ein Glänz­verfahren für Teile aus Aluminium oder Aluminium-Legierungen aufzu­zeigen, mit dem eine optimale Oberflächenreflektion bzw. Glanzwirkung der Teile erzeugt werden kann.The present invention is based on the object of demonstrating a glossing process for parts made of aluminum or aluminum alloys, with which an optimal surface reflection or gloss effect of the parts can be generated.

Zur Lösung dieser Aufgabe wird ein Verfahren vorgeschlagen, das sich erfindungsgemäß dadurch auszeichnet, daß die Teile in einem mittels Gleichstrom betriebenen alkalischen Elektrolyten der Zusammensetzung:
Na₃PO₄ (Trinatriumphosphat) 120 g/l
NA₂CO₃ (Dinatriumcarbonat) 330 g/l
AlPO₄ (Aluminiumphosphat) 10 g/l
Extrakte aus Buchenholz 5 ml/l
bei einer Betriebstemperatur von etwa 70 - 80 o C behandelt werden.To achieve this object, a method is proposed which, according to the invention, is characterized in that the parts in an alkaline electrolyte of the composition operated by means of direct current:
Na₃PO₄ (trisodium phosphate) 120 g / l
NA₂CO₃ (disodium carbonate) 330 g / l
AlPO₄ (aluminum phosphate) 10 g / l
Extracts from beech wood 5 ml / l
be treated at an operating temperature of around 70 - 80 o C.

Der besondere Vorteil dieses Verfahrens besteht in der Erzeugung einer optimalen Oberflächenreflektion bzw. Glanzwirkung von Aluminium­teilen (Profilleisten od. dgl) zur Herstellung von farbigen und natur­farbenen, anodisch erzeugten Eloxalschichten. Dadurch ergibt sich als weiterer wesentlicher Vorteil, eine erhebliche Reduktion der Nach­arbeit durch Glänzfehler.The particular advantage of this process consists in the generation of an optimal surface reflection or gloss effect of aluminum parts (profile strips or the like) for the production of colored and natural-colored, anodically produced anodized layers. This results in another significant advantage, a considerable reduction in reworking due to glossy defects.

Bevorzugterweise werden die Teile in dem Elektrolyten einer 2-Stufen­behandlung unterzogen, wobei die Teile in der ersten Stufe, bei einer Betriebstemperatur von etwa 80 o C vorgeglänzt und in der zweiten Stufe, bei einer Betriebstemperatur von etwa 70 o C nachgeglänzt werden. Der Elektrolyt wird also in zwei Stufen, Vorglänzen und Nach­glänzen, betrieben, wobei die beiden Stufen eine gleichartige Zusammen­setzung enthalten und sich lediglich in der Betriebstemperatur unter­scheiden.The parts preferably are subjected in the electrolyte of a 2-stage treatment, the parts vorgeglänzt in the first stage, at an operating temperature of about 80 o C and nachgeglänzt in the second stage, at an operating temperature of about 70 ° C. The electrolyte is therefore operated in two stages, pre-glossing and post-glossing, the two stages containing a similar composition and differing only in the operating temperature.

Weiterhin ist vorgesehen, daß die Teile in der ersten Behandlungsstufe mit einer Stromdichte von etwa 3 A/dm² und in der zweiten Behandlungs­stufe mit einer Stromdichte von etwa 1,5 - 2 A/dm² exponiert werden. Dabei wird, bedingt durch die höhere Betriebstemperatur der ersten Stufe, bei einer Stromdichte von 3 A/dm² ein höherer Materialabtrag erzielt.It is also provided that the parts are exposed in the first treatment stage with a current density of approximately 3 A / dm² and in the second treatment stage with a current density of approximately 1.5-2 A / dm². Due to the higher operating temperature of the first stage, a higher material removal is achieved with a current density of 3 A / dm².

Die Teile werden insgesamt etwa 18 Minuten lang exponiert. Dabei hat es sich als besonders vorteilhaft erwiesen, daß die angelegte Spannung etwa eine Minute vor Ablauf der Expositionszeit für etwa 2 - 10 Sekunden unterbrochen wird. Hierdurch wird erreicht, daß der beim Glänzen entstandene Glänzfilm größtenteils abgelöst wird, ohne die Oberfläche anzuätzen.The parts are exposed for a total of about 18 minutes. It has proven to be particularly advantageous that the voltage applied is interrupted for about 2 to 10 seconds about one minute before the exposure time expires. It is hereby achieved that the gloss film formed during the shining is largely removed without etching the surface.

Eine besonders vorteilhafte Weiterbildung der Erfindung besteht darin, daß der Elektrolyt (kontinuierlich oder diskontinuierlich) filtriert wird, daß der dabei entstehende Filterkuchen gespült wird und daß die dabei in gelöster Form zurückgewonnenen Chemikalien dem Elektroly­ten wieder zugeführt werden. Durch diese Maßnahme wird das erfindungs­gemäße Verfahren besonders umweltschonend, wie auch eine beträchtliche Kostenreduzierung hinsichtlich Deponieabgaben und Einleiterdirektver­ordnung erzielt wird. Der Elektrolyt kann insbesondere mittels einer Kammerfilterpresse filtriert werden.A particularly advantageous development of the invention consists in that the electrolyte is filtered (continuously or discontinuously), that the filter cake formed is rinsed, and that the chemicals recovered in this form are returned to the electrolyte. This measure makes the method according to the invention particularly environmentally friendly, as is also a considerable reduction in costs with regard to landfill charges and direct discharges. The electrolyte can be filtered in particular by means of a chamber filter press.

Es kann weiterhin vorgesehen werden, daß die Teile in einem kathodisch geschalteten Behälter aus Baustahl behandelt werden, wobei die Teile als Anoden verwendet werden. Auch kann vorgesehen sein, daß ein mit Heiz- und Kühleinrichtungen ausgestatteter Behälter verwendet wird. Schließlich ist es von Vorteil, wenn ein Behälter verwendet wird, der einen zu einer Filterstation führenden Überlauf und einen von der Filterstation kommenden Zulauf aufweist.It can further be provided that the parts are treated in a cathodically connected container made of structural steel, the parts being used as anodes. It can also be provided that a container equipped with heating and cooling devices is used. Finally, it is advantageous if a container is used which has an overflow leading to a filter station and an inlet coming from the filter station.

Claims (9)

1. Glänzverfahren für Teile aus Aluminium oder Aluminium-Legierungen, dadurch gekennzeichnet, daß die Teile in einem mittels Gleichstrom betriebenen alkalischen Elektrolyten der Zusammensetzung:
Na₃PO₄ (Trinatriumphosphat) 120 g/l
NA₂CO₃ (Dinatriumcarbonat) 330 g/l
AlPO₄ (Aluminiumphosphat) 10 g/l
Extrakte aus Buchenholz 5 ml/l
bei einer Betriebstemperatur von etwa 70 - 80 o C behandelt werden.1. Shining process for parts made of aluminum or aluminum alloys, characterized in that the parts in an alkaline electrolyte operated by means of direct current of the composition:
Na₃PO₄ (trisodium phosphate) 120 g / l
NA₂CO₃ (disodium carbonate) 330 g / l
AlPO₄ (aluminum phosphate) 10 g / l
Extracts from beech wood 5 ml / l
be treated at an operating temperature of around 70 - 80 o C. 2. Glänzverfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Teile in dem Elektrolyten einer 2-Stufenbehandlung unterzogen werden, wobei die Teile in der ersten Stufe, bei einer Betriebs­temperatur von etwa 80 o C vorgeglänzt und in der zweiten Stufe, bei einer Betriebstemperatur von etwa 70 o C nachgelänzt werden.2. Shining process according to claim 1, characterized in that the parts in the electrolyte are subjected to a 2-stage treatment, the parts being pre-polished in the first stage, at an operating temperature of about 80 o C and in the second stage, at an operating temperature of about 70 o C can be added. 3. Glänzverfahren nach Anspruch 2, dadurch gekennzeichnet, daß die Teile in der ersten Behandlungsstufe mit einer Stromdichte von etwa 3 A/dm² und in der zweiten Behandlungsstufe mit einer Strom­dichte von etwa 1,5 - 2 A/dm² exponiert werden.3. Shining method according to claim 2, characterized in that the parts are exposed in the first treatment stage with a current density of about 3 A / dm² and in the second treatment stage with a current density of about 1.5 - 2 A / dm². 4. Glänzverfahren nach wenigstens einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Teile insgesamt etwa 18 Minuten lang expo­niert werden.4. Shining method according to at least one of claims 1 to 3, characterized in that the parts are exposed for a total of about 18 minutes. 5. Glänzverfahren nach wenigstens einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß die angelegte Stromspannung etwa eine Minute vor Ablauf der Expositionszeit für etwa 2 - 10 Sekunden unterbro­chen wird.5. Shine method according to at least one of claims 1 to 4, characterized in that the applied voltage is interrupted for about 2 to 10 seconds before the expiration of the exposure time. 6. Glänzverfahren nach wenigstens einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß der Elektrolyt (kontinuierlich oder diskonti­nuierlich) filtriert wird, daß der dabei entstehende Filterkuchen gespült wird und die die dabei in gelöster Form zurückgewonnenen Chemikalien dem Elektrolyten wieder zugeführt werden.6. Shining process according to at least one of claims 1 to 5, characterized in that the electrolyte is filtered (continuously or discontinuously), that the filter cake formed is rinsed and the chemicals recovered in dissolved form are fed back to the electrolyte. 7. Glänzverfahren nach wenigstens einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß die Teile in einem kathodisch geschalteten Behälter aus Baustahl behandelt werden, wobei die Teile als Anoden verwendet werden.7. Shining method according to at least one of claims 1 to 6, characterized in that the parts are treated in a cathodically connected container made of structural steel, the parts being used as anodes. 8. Glänzverfahren insbesondere nach Anspruch 7, dadurch gekennzeichnet, daß ein mit Heiz- und Kühleinrichtungen ausgestatteter Behälter verwendet wird.8. Shining method in particular according to claim 7, characterized in that a container equipped with heating and cooling devices is used. 9. Glänzverfahren insbesondere nach Anspruch 7 oder 8, dadurch gekenn­zeichnet, daß ein Behälter verwendet wird, der einen zu einer Filterstation führenden Überlauf und einen von der Filterstation kommenden Zulauf aufweist.9. Shining method in particular according to claim 7 or 8, characterized in that a container is used which has an overflow leading to a filter station and an inlet coming from the filter station.
EP19900105559 1989-05-26 1990-03-23 Polishing process Ceased EP0399170A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3917184 1989-05-26
DE3917184A DE3917184A1 (en) 1989-05-26 1989-05-26 polishing methods

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EP0399170A2 true EP0399170A2 (en) 1990-11-28
EP0399170A3 EP0399170A3 (en) 1991-01-16

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EP19900105559 Ceased EP0399170A3 (en) 1989-05-26 1990-03-23 Polishing process

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US (1) US4995951A (en)
EP (1) EP0399170A3 (en)
JP (1) JPH0313595A (en)
DE (1) DE3917184A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3917188A1 (en) * 1989-05-26 1990-11-29 Happich Gmbh Gebr PROCESS FOR PRODUCING COLORED SURFACES ON PARTS OF ALUMINUM OR ALUMINUM ALLOYS
US5616231A (en) * 1996-05-08 1997-04-01 Aluminum Company Of America Electrobrightening process for aluminum alloys
JP5017050B2 (en) * 2007-10-19 2012-09-05 三菱アルミニウム株式会社 Method for producing surface-treated aluminum material
WO2011038476A1 (en) * 2009-09-30 2011-04-07 Atomic Energy Of Canada Limited (Aecl) Circumferential sampling tool having multiple sample cutters

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3365380A (en) * 1964-02-24 1968-01-23 Kyowa Hakko Kogyo Kk Electrolytic polishing solution and the process of polishing therewith
US3390063A (en) * 1964-12-28 1968-06-25 Kenneth C. Working Electrolytes and method for anodizing aluminum
GB1569101A (en) * 1978-05-31 1980-06-11 British Aluminium Co Ltd Electrobrightening of aluminium and aluminium-base alloys
JPS58153800A (en) * 1982-03-10 1983-09-12 Honda Motor Co Ltd Electrolytic polishing treatment of aluminum or aluminum alloy

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE881291C (en) * 1939-05-17 1953-06-29 Vaw Ver Aluminium Werke Ag Process for the production of smooth and shiny surfaces on objects made of aluminum and aluminum alloys
US4247378A (en) * 1979-09-07 1981-01-27 The British Aluminum Company Limited Electrobrightening of aluminium and aluminium-base alloys

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3365380A (en) * 1964-02-24 1968-01-23 Kyowa Hakko Kogyo Kk Electrolytic polishing solution and the process of polishing therewith
US3390063A (en) * 1964-12-28 1968-06-25 Kenneth C. Working Electrolytes and method for anodizing aluminum
GB1569101A (en) * 1978-05-31 1980-06-11 British Aluminium Co Ltd Electrobrightening of aluminium and aluminium-base alloys
JPS58153800A (en) * 1982-03-10 1983-09-12 Honda Motor Co Ltd Electrolytic polishing treatment of aluminum or aluminum alloy

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 7, Nr. 273 (C-198)[1418], 6. Dezember 1983; & JP-A-58 153 800 (HONDA GIKEN KOGYO) 12-09-1983 *

Also Published As

Publication number Publication date
DE3917184A1 (en) 1990-11-29
US4995951A (en) 1991-02-26
JPH0577754B2 (en) 1993-10-27
EP0399170A3 (en) 1991-01-16
JPH0313595A (en) 1991-01-22
DE3917184C2 (en) 1991-08-08

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