DE102006052170A1 - Anodic oxide layer for electrical conductors, in particular conductors made of aluminum, method for producing an anodic oxide layer and electrical conductor with anodic oxide layer - Google Patents

Abstract

An anodic oxide layer for electrical conductors, particularly conductors of aluminum, a method for forming an anodic oxide layer and an electrical conductor with anodic oxide layer are intended to improve the breakdown voltage safety and the ductility include: a) the use of an electrolyte in the formation of the oxide layer, the b) the application of at least one selected type of current and c) in the case of a compacting after-treatment of the surface of the oxide layer, the introduction of a substance which is based on the reference of a recompression of an aggregate form of water such that the oxide layer d) produced has a Martens hardness [HM] of> 2300, e) has an increase in wear resistance compared to conventional characteristics, f) receives an improvement in ductility, g) has improved corrosion resistance, and h) a breakdown voltage safety of more than 300 V can be exposed.

Description

field of use

The The invention relates to an anodic oxide layer for electrical conductors, in particular Ladder made of aluminum, e.g. in the form of ribbons or wires. Further The invention relates to a method for producing an anodic Oxide layer. Finally, concerns the invention then anodized electrical conductor. The Invention is for an embodiment of the electrical conductor as an electrical winding or Coil z. B. applicable in a transformer.

State of the art

According to the US 4,605,480 a device for the continuous anodization of aluminum strips is known, with the tapes are unilaterally anodized with direct current in various electrolytes, for example sulfuric, oxalic and phosphoric acid. The tape to be anodized is guided horizontally through the bath. The oxide layer is formed on the band side, which is opposite to the cathode. As the electrolyte, for example, 20% sulfuric acid may be used at a temperature of 40 ° C, an anodic current density of 10A / dm ^2, and a voltage of 30V.

After US 5,693,208 A process has been known in which the aluminum strip is continuously passed through the bath, wherein the anodization process consists of two sub-stages, which operate in different voltages. In the first stage, a feinpo rige layer is produced, while the result after the second stage is a coarse-pored layer of appropriate thickness.

In another process according to the EP 318 403 The aluminum strip is continuously passed through the bath at a very high speed. The electrolyte is based on inorganic acids and contains functional carboxyl and / or hydroxyl groups as well as metal salts such as trivalent chromium salt. The oxide layers produced in this way find their use as a primer for organic layers and for the production of packaging.

Furthermore, the disclosure DE 100 65 649 A1 an apparatus and method for electrochemical metallizing, etching, oxidizing and reducing electrically conductive and flexible tapes in continuous flow systems. In an electrolytic bath are electrode rollers, which are provided on the lateral surface with an ion-permeable and electrically insulating layer. The material to be treated is passed through the system during the pass around the electrode rollers. The bath tension for electrolytic treatment is applied to the material to be treated and to the electrode roller (counter electrode).

In addition, the describes US 6,261,437 a method and apparatus for anodizing aluminum wires for high voltage equipment and electrical equipment. A portion of certain length of the metal conductor is wrapped around the holder, so that all windings are separated from each other on a comb-shaped device. The winding holder with the wound wire is immersed in the electrolyte. The wire is connected to the plus pole of the power source and anodized. The oxide layer produced in this way has sufficient adhesive strength and good insulating properties.

With an operating electrolyte according to the DE 101 04 714 C for an aluminum electrolytic capacitor comprising ethylene glycol, p-nitrobenzoic acid, ammonium hypophosphite, ammonium pentaborate, polyethylene glycol, MMA 10RA, and ammonium methyl benzoate, is said to add the addition of methyl benzoic acid, which sterically blocks the subsequent reaction of the acid group with ethylene glycol by its methyl substitution Operating electrolyte can be produced with improved long-term stability of the electrical conductivity. The acids used in this electrolyte function as the insulating ability improving substances. These could be used as an additive for aftertreatment solutions.

After another in the US 4,715,936 The process described for anodizing aluminum for aluminum electrolytic capacitors is an electrolyte suitable for anodic oxidation of aluminum, consisting of solutions of amino acids with a pH of 5.5 to 8.5. This electrolyte is used in the anodization of aluminum foils to produce an insulating barrier layer.

Subsequent to the aftertreatment outlined above, the DE teaches 196 80 596C a process for the aftertreatment of the microporous oxide layers produced by anodic or plasma-chemical anodic oxidation on workpieces made of aluminum, magnesium, titanium. This method is characterized in that silica in the form of a lyosol in which the colloidally dispersed SiO ₂ particles are smaller in at least one dimension than the diameter of the pores or capillaries of the microporous cover layer. The particles are introduced under varying pressure conditions in the pores or capillaries.

After all, this is after the DE 41 24 730 a method for incorporation of fluoropolymers into microporous, by anodic Oxida tion surfaces made of aluminum, magnesium or their alloys known in such a way that the fluoropolymers are applied as a solution or suspension with a particle size of 1 to 50 nm on the microporous oxide layer produced by anodic oxidation and the fluoropolymers wholly or partly in the presence polymerize the light metal objects to be coated and fused or sintered by heating. The surface of the oxide layer should be coated with fluoropolymers by polymerization of fluoromonomers or further polymerization of fluoro-oligomers and connected to these fluoropolymers in the micropores.

in the With regard to the problem to be solved by the invention, the Evaluation of this patent literature and other relevant specialist literature, that the professional world is big Part already with the influence of the deposition conditions (electrolyte, Temperature, current density, type of current, voltage) on the layer thickness, the layer structure and the layer properties (preferably the Hardness) has dealt with.

During the Influence of the layer thickness on the breakdown voltage largely However, there are no reliable findings on dependency this property characteristic of the deposition conditions and of the layer structure.

Similarly The prior art gives only a few pointers to the context between deposition conditions, layer structure and deformation behavior (Ductility) the layer.

Even though on the possibility an increase in Breakdown voltage due to redensification (hot water, steam) sporadically, reliable results are missing.

As well The prior art provides no evidence of the effect of aftertreatment with plastics (e.g., PTFE) on the breakdown voltage and the ductility the layer.

ways for the simultaneous deposition of several components (co-deposition of particles) in connection with the anodizing have been so far also not shown.

It were indeed additives to the electrolyte for itself but their effect is on certain properties (Breakdown voltage, ductility) not fundamental and related.

The also relates to isolated treatment steps, which are not based on systematic investigations.

Consequently opens still a wide field of problems to be solved.

Presentation of the invention

• 1. Bei der Elektrolytzusammensetzung soll der häufig angewendete Schwefelsäure-Elektrolyt die Referenz darstellen. Hiervon ausgehend sind die Elektrolytart und -zusammensetzung zu variieren.
• 2. Es soll der Einfluss der Temperatur anhand ausgewählter Elektrolyten berücksichtigt werden.
• 3. Es sind vorrangig Wechselstrom und Pulsstrom sowie Überlagerungen der einzelnen Stromarten zu berücksichtigen, dabei soll Gleichstrom in Kombination mit unterschiedlichen Wechselströmen, wie in Sinus-, Rechteck-, Trapez- oder Dreieckform anwendbar sein.
• 4. Als Nachbehandlung soll eine Nachverdichtung erfolgen. Aussehend hiervon sind die Nachbehandlungen mit für dieses Verfahren neuen, nachträglich eingebrachten Stoffen zu verbessern.
• 5. Zur Lösung der Aufgabenstellung sind im Ergebnis die – Durchschlagspannung und – Duktilität z. B. an Hand modifizierter Dornbiegeversuche Des anodisierten elektrischen Leiters in Kenngrößen messbar anzugeben.

The invention therefore has the object of developing on the basis of investigations an anodic oxide layer for electrical conductors, in particular conductors made of aluminum, a method for producing an anodic oxide layer and electrical conductor with anodic oxide layer and its formation, with which both the breakdown voltage as well as the ductility can be positively influenced. This considering the following criteria:

• 1. In the electrolyte composition, the commonly used sulfuric acid electrolyte should be the reference. On this basis, the electrolyte type and composition are to be varied.
• 2. The influence of temperature on the basis of selected electrolytes shall be considered.
• 3. Priority must be given to alternating current and pulse current, as well as superimpositions of the individual types of current, whereby DC should be applicable in combination with different alternating currents, such as sinusoidal, rectangular, trapezoidal or triangular shapes.
• 4. Post-treatment should be carried out after re-compaction. Looking to this, the aftertreatments with new, subsequently introduced substances for this process should be improved.
• 5. To solve the task are in the result of the - breakdown voltage and - ductility z. B. on hand modified Dornbiegeversuche the anodized electrical conductor in parameters measurable indicate.

• a) ein Elektrolyt verwendet wird, der sich in seiner Art und Zusammensetzung an der Referenz eines Schwefelsäure-Elektrolyten orientiert und ggf. in seiner Zusammensetzung variierbar ist,
• b) mindestens eine ausgewählte Stromart und -form und ggf. deren Überlagerungen zur Anwendung gelangen und
• c) bei einer verdichtenden Nachbehandlung der Oberfläche der Oxidschicht ein Stoff eingebracht wird, der sich an der Referenz einer Nachverdichtung einer Aggregatform von Wasser orientiert, dadurch, dass die erzeugte Oxidschicht
• d) eine Martenshärte [HM] von > 2300 aufweist,
• e) eine Erhöhung der Verschleissfestigkeit im Vergleich zu üblichen Kenngrössen, wie – eine Verschleisstiefe von ca. 100 μm auf < 70 μm gemäss Schwingverschleisstest sowie – eine Ritzenergiedichte [J/mm²] von 0,03 auf > 0,05 bei Normalkräften von 2 N und von 0,45 auf > 0,5 bei Normalkräften von 50 N gemäss Ritzprüfversuch besitzt,
• f) eine Verbesserung der Duktilität (Rissempfindlichkeit, Rissbildungsneigung) im Vergleich von 0,24 auf 0,30 [Dehnung beim 1. Riss, wobei als Maß für die Duktilität die Bruchelongation in % gilt] gemäß Bedingungen der Mikrobiegeprüfung mit einer Maximalkraft von 50 N, einem Weg von max. 4800 μm, einem Probestück von l 45 × b 10 × h 0,3 mm, einer Prüfgeschwindigkeit von 20 μm/s und einer Stützweite von 40 mm erhält,
• g) eine Korrosionsbeständigkeit durch eine Schichtdicke der Oxidschicht ab 5 μm aufweist und
• h) bei einer Oxidschichtdicke von ca. 6 μm und einer thermischen Beanspruchung von ca. 2 h mit 250° C eine Durchschlagsspannungssicherheit von mehr als 300 V aussetzbar ist.

According to the invention is characterized according to claim 1, the anodic oxide layer for electrical conductors, in particular conductors of aluminum in the form of bands or wires, wherein for the production of the oxide layer

• a) an electrolyte is used which is oriented in its type and composition to the reference of a sulfuric acid electrolyte and is optionally variable in its composition,
• b) at least one selected type and shape of electricity and, where applicable, their superpositions are used; and
• c) in a compacting after-treatment of the surface of the oxide layer, a substance is introduced, which is based on the reference of a recompression of an aggregate form of water, characterized in that the oxide layer produced
• d) has a Martens hardness [HM] of> 2300,
• e) an increase in wear resistance compared to conventional parameters, such as A wear depth of approx. 100 μm to <70 μm in accordance with the vibrational wear test; and a rake energy density [J / mm ² ] of 0.03 to> 0.05 at normal forces of 2 N and from 0.45 to> 0.5 at normal forces of 50 N according to scratch test,
• f) an improvement in ductility (crack sensitivity, cracking tendency) from 0.24 to 0.30 [elongation at the 1st crack, using as a measure of the ductility the fracture elongation in%] according to conditions of the microbend test with a maximum force of 50N , a way of max. 4800 microns, a test piece of l 45 × b 10 × h 0.3 mm, a test speed of 20 microns / s and a span of 40 mm receives,
• g) has a corrosion resistance by a layer thickness of the oxide layer from 5 microns, and
• h) at an oxide layer thickness of about 6 microns and a thermal stress of about 2 h at 250 ° C, a breakdown voltage of more than 300 V can be suspended.

Further features are described in claims 2 to 3, according to which the increased wear resistance of the oxide layer according to the scratch test test has a Ritzenergiedichte [J / mm ² ] of <0.6 at 50 N and / or the improved ductility from a size of> 0.31 lies.

• a) ein Bad mit einem Elektrolyten, der sich in seiner Art und Zusammensetzung an der Referenz eines Schwefelsäure-Elektrolyten orientiert und ggf. in seiner Zusammensetzung variierbar ist,
• b) die Einspeisung mindestens einer ausgewählten Stromart und -form und ggf. deren Überlagerungen,
• c) Einbringung einer Farbe und Färben mit anschließendem Spülen der Oxidschicht
• d) eine verdichtende Nachbehandlung der Oberfläche der Oxidschicht mit einem einzubringenden Stoff wie heißem Wasser und
• e) die Einhaltung einer vorgegebenen Behandlungstemperatur.
• Erfindungsgemäß sind demnach
• f) die Verwendung eines Elektrolyten, aufweisend die Bestandteile 15 ... 30 Vol.% Schwefelsäure mit einem Zusatz von 5 ... 30 g Oxalsäure/l Schwefelsäure,
• g) die Einleitung eines Wechselstroms in Sinus-, Rechteck-, Dreieck-, oder Trapezform oder einer Kombination aus diesen und mit einer Frequenz bis zu 700 Hz,
• h) die Verwendung einer Farbe als Stoff vor der verdichtenden Nachbehandlung und
• i) die Einhaltung einer Temperatur von 25 ... 50° C
• j) vorgesehen.

The process for producing this anodic oxide film for electrical conductors has

• a) a bath with an electrolyte which is oriented in its type and composition to the reference of a sulfuric acid electrolyte and is optionally variable in its composition,
• b) the feeding of at least one selected type and shape of electricity and, where applicable, their superpositions,
• c) introduction of a color and dyeing with subsequent rinsing of the oxide layer
• d) a compacting after-treatment of the surface of the oxide layer with a substance to be introduced, such as hot water and
• e) compliance with a given treatment temperature.
• Accordingly, according to the invention
• (f) the use of an electrolyte containing the constituents of 15 to 30% by volume of sulfuric acid with an addition of 5 to 30 g of oxalic acid or 1 of sulfuric acid;
• g) the introduction of an alternating current in sine, rectangular, triangular or trapezoidal form or a combination of these and with a frequency up to 700 Hz,
• h) the use of a paint as a substance before the compacting treatment and
• i) maintaining a temperature of 25 ... 50 ° C
• j).

there the electrolyte should advantageously contain 20% by volume of sulfuric acid, of 15 g of oxalic acid / l sulfuric acid and an enrichment with Al particles in a concentration in the Range of about 3.5 g Al ... about 13 g Al / l electrolyte, wherein the Concentration depending is variable by the passage speed of the conductor in the bath, exhibit.

Of the introduced alternating current can be in alternating pulse shapes and / or Pulse trains are used, thereby increasing the breakdown voltage and ductility the layer improved.

Of the introduced alternating current has a voltage of less 50V up.

The Anodization time is <120 s and is in dependence from the passage speed of the conductor in the bath and / or the Amperage and / or the treatment interval variable.

• – Farbehandlung wie durch Tauchen,
• – Behandlung mit heißem Wasser oder Wasserdampf, wodurch sich die Poren auf der gefärbten Oberfläche der Oxidschicht verschließen.

The aftertreatment with the respective anodizing color includes the steps

• - color treatment as by dipping,
• - Treatment with hot water or steam, whereby the pores close on the colored surface of the oxide layer.

priority the use of the color red takes place, whereby also the use the color green is possible.

The colors used for re-compaction are current, such as so-called GTL Oxalanfarben or Clariant colors.

• a) eine Oxidschicht entsprechend einer Durchschlagsspannungssicherheit von 10 bis 60 V/Schichtdicke μm,
• b) eine Martenshärte [HM] von > 2300,
• c) eine Erhöhung der Verschleissfestigkeit im Vergleich zu üblichen Kenngrössen wie
• – eine Verschleißtiefe von ca. 100 μm auf < 70 μm gemäss Schwingverschleisstest sowie
• – eine Ritzenergiedichte [J/mm²] von 0,03 auf > 0,05 bei Normalkräften von 2 N und von 0,45 auf > 0,5 bei Normalkräften von 50 N gemäss Ritzprüfversuch,
• d) eine Verbesserung der Duktilität (Rissempfindlichkeit, Rissbildungsneigung) im Vergleich von 0,24 auf 0,30 [Dehnung beim 1. Riss in % wie oben] gemäß Bedingungen der Mikrobiegeprüfung mit einer Maximalkraft von 50 N, einem Weg von max. 4800 μm, einem Probestück von l 45 × b 10 × h 0,3 mm, einer Prüfgeschwindigkeit von 20 μm/s und einer Stützweite von 40 mm und
• e) eine Korrosionsbeständigkeit durch eine Schichtdicke der Oxidschicht ab 5 μm

auf.The electrical conductor with anodic oxide layer, in its use as in coils, windings or the like. According to the invention

• a) an oxide layer corresponding to a breakdown voltage safety of 10 to 60 V / layer thickness μm,
• b) a Marten hardness [HM] of> 2300,
• c) an increase in wear resistance compared to conventional parameters such as
• - a wear depth of about 100 microns to <70 microns according to vibration wear test and
• A rake energy density [J / mm ² ] of 0.03 to> 0.05 at normal forces of 2 N and of 0.45 to> 0.5 at normal forces of 50 N according to the scratch test test,
• d) improvement in ductility (crack sensitivity, cracking tendency) from 0.24 to 0.30 [% elongation at 1st crack as above] according to conditions of microbend test with a maximum force of 50 N, a path of max. 4800 microns, a test piece of l 45 × b 10 × h 0.3 mm, a test speed of 20 microns / s and a span of 40 mm and
• e) a corrosion resistance by a layer thickness of the oxide layer from 5 microns

on.

This electrical conductor has at an oxide layer thickness of about 6 microns and a Thermal stress of about 2 h at 250 ° C a breakdown voltage safety of more than 300 V.

at an oxide layer thickness of z. B. about 6 microns is an insulation resistance from Z. B.> 200 k Ω reached.

The oxide layer has a porosity of 3 to 8 pores / nm ² .

Best way to execute the invention

• a) ein Elektrolyt verwendet wird, der sich in seiner Art und Zusammensetzung an der Referenz eines Schwefelsäure-Elektrolyten orientiert und ggf. in seiner Zusammensetzung variierbar ist,
• b) mindestens eine ausgewählte Stromart und -form und ggf. deren Überlagerungen zur Anwendung gelangen und
• c) bei einer verdichtenden Nachbehandlung der Oberfläche der Oxidschicht ein Stoff eingebracht wird, der sich an der Referenz einer Nachverdichtung einer Aggregatform von Wasser orientiert, besitzt im Ergebnis der verfahrensgemäßen Behandlung nach der Erfindung
• d) eine Martenshärte [HM] von > 2300,
• e) eine Erhöhung der Verschleißfestigkeit im Vergleich zu üblichen Kenngrößen wie
• • eine Verschleißtiefe von ca. 100 μm auf < 70 μm gemäß Schwingverschleißtest sowie
• • eine Ritzenergiedichte [J/mm²] von 0,03 auf > 0,05 bei Normalkräften von 2 N und von 0,45 auf > 0,5 bei Normalkräften von 50 N gemäß Ritzprüfversuch,
• f) eine Verbesserung der Duktilität (Rissempfindlichkeit, Rissbildungsneigung) im Vergleich von 0,24 auf 0,30 [Dehnung beim 1. Riss in %] gemäß Bedingungen der Mikrobiegeprüfung mit einer Maximalkraft von 50 N, einem Weg von max. 4800 μm, einem Probestück von l 45 × b 10 × h 0,3 mm, einer Prüfgeschwindigkeit von 20 μm/s und einer Stützweite von 40 mm,
• g) eine Korrosionsbeständigkeit durch eine Schichtdicke der Oxidschicht ab 5 μm und ist
• h) bei einer Oxidschichtdicke von ca. 6 μm und einer thermischen Beanspruchung von ca. 2 h mit 250° C einer Durchschlagsspannungssicherheit von mehr als 300 V aussetzbar.

The generated anodic oxide layer for electrical conductors, in particular conductors of aluminum in the form of bands or wires, wherein for generating the oxide layer

• a) an electrolyte is used which is oriented in its type and composition to the reference of a sulfuric acid electrolyte and is optionally variable in its composition,
• b) at least one selected type and shape of electricity and, where applicable, their superpositions are used; and
• c) in a compacting after-treatment of the surface of the oxide layer, a substance is introduced, which is based on the reference of a recompression of an aggregate form of water, has as a result of the method according to the invention treatment
• d) Martens hardness [HM] of> 2300,
• e) an increase in wear resistance compared to conventional parameters such as
• • a wear depth of approx. 100 μm to <70 μm according to the vibration wear test as well as
• A Ritzenergiedichte [J / mm ² ] of 0.03 to> 0.05 at normal forces of 2 N and from 0.45 to> 0.5 at normal forces of 50 N according to Ritzprüfversuch,
• f) an improvement in ductility (crack sensitivity, cracking tendency) from 0.24 to 0.30 [% elongation at 1 st%] under conditions of microbend testing with a maximum force of 50 N, a path of max. 4800 microns, a test piece of l 45 × b 10 × h 0.3 mm, a test speed of 20 microns / s and a span of 40 mm,
• g) a corrosion resistance by a layer thickness of the oxide layer from 5 microns and is
• h) at an oxide layer thickness of about 6 microns and a thermal stress of about 2 h at 250 ° C a breakdown voltage of more than 300 V exposable.

The increased wear resistance of the oxide layer according to the scratch test test can have a Ritzenergiedichte [J / mm ² ] of <0.6 at 50 N, and the improved ductility from a size of> 0.31.

• a) ein Bad mit einem Elektrolyten, der sich in seiner Art und Zusammensetzung an der Referenz eines Schwefelsäure-Elektrolyten orientiert und ggf. in seiner Zusammensetzung variierbar ist,
• b) die Einspeisung mindestens einer ausgewählten Stromart und -form und ggf. deren Überlagerungen,
• c) die Einbringung einer Farbe und Färben mit anschließendem Spülen der Oxidschicht
• d) eine verdichtende Nachbehandlung der Oberfläche der Oxidschicht mit einem einzubringenden Stoff wie heißem Wasser und
• e) die Einhaltung einer vorgegebenen Behandlungstemperatur.

The method for producing this andean oxide layer for electrical conductors has

• a) a bath with an electrolyte which is oriented in its type and composition to the reference of a sulfuric acid electrolyte and is optionally variable in its composition,
• b) the feeding of at least one selected type and shape of electricity and, where applicable, their superpositions,
• c) the introduction of a color and dyeing with subsequent rinsing of the oxide layer
• d) a compacting after-treatment of the surface of the oxide layer with a substance to be introduced, such as hot water and
• e) compliance with a given treatment temperature.

• f) die Verwendung eines Elektrolyten, aufweisend die Bestandteile 15 ... 30 Vol. % Schwefelsäure mit einem Zusatz von 5 ... 30 g Oxalsäure/l Schwefelsäure,
• g) die Einleitung eines Wechselstroms in Sinus-, Rechteck-, Dreieck-, oder Trapezform oder einer Kombination aus diesen und mit einer Frequenz bis zu 700 Hz,
• h) die Verwendung einer Farbe als Stoff vor der verdichtenden Nachbehandlung und
• i) die Einhaltung einer Temperatur von 25 ... 50° C.

According to the treatment is carried out by

• (f) the use of an electrolyte containing the constituents of 15 to 30% by volume of sulfuric acid with an addition of 5 to 30 g of oxalic acid or 1 of sulfuric acid;
• g) the introduction of an alternating current in sine, rectangular, triangular or trapezoidal form or a combination of these and with a frequency up to 700 Hz,
• h) the use of a paint as a substance before the compacting treatment and
• i) maintaining a temperature of 25 ... 50 ° C.

there the electrolyte should advantageously have a proportion of 20 vol.% Sulfuric acid.

Preferably For example, the electrolyte may have a proportion of 15 g of oxalic acid / l of sulfuric acid.

Advantageous it is the electrolyte with Al particles in one concentration in the range of approx. 3.5 g Al ... approx. 13 g Al / l electrolyte, the concentration depending on of the passage speed of the conductor in the bath is variable.

Of the introduced alternating current can be in the combination form trapezoid - sine wave be used. Also this is in the combination form sine, rectangle, Harness selectable. It is conceivable out for special treatments changing pulse shapes and / or pulse sequences of the current, the breakdown voltage strength and ductility of the layer to improve.

Advantageously, the introduced AC voltage of <50V.

The Anodization time is <120 s, depending on from the passage speed of the conductor in the bath and / or the amperage and / or the treatment interval can be varied up to this limit.

• – Erzeugung der erforderlichen Schichtdicke in etwa proportional zur erforderlichen Durchschlagsspannungsfestigkeit des anodisierten Leiters,
• – Einbringung der jeweiligen Eloxalfarbe in das Bad und Farbehandlung wie durch Tauchen,
• – Spülen,
• – verdichtende Behandlung mit heißem Wasser oder Wasserdampf zum Verschließen der Poren auf der gefärbten Oberfläche der Oxidschicht.

The method basically comprises the steps

• Generation of the required layer thickness approximately proportional to the required breakdown voltage strength of the anodized conductor,
• - introduction of the respective anodizing color into the bath and color treatment as by dipping,
• - Do the washing up,
• - Compressive treatment with hot water or steam to close the pores on the colored surface of the oxide layer.

When Eloxalfarbe is used the color red or green.

The used colors can current, such as so-called GTL-Oxalanfarben or Clariantfarben be.

The Procedure is operated by software to control / regulation the power sources to generate voltages of any frequency and shape.

The Use of a bath for a dip dye is convenient for the process.

• • eine Verschleißtiefe von ca. 100 μm auf < 70 μm gemäß Schwingverschleißtest sowie
• • eine Ritzenergiedichte [J/mm²] von 0,03 auf > 0,05 bei Normalkräften von 2 N und von 0,45 auf > 0,5 bei Normalkräften von 50 N gemäß Ritzprüfversuch,

eine Verbesserung der Duktilität (Rissempfindlichkeit, Rissbildungsneigung) im Vergleich von 0,24 auf 0,30 [Dehnung beim 1. Riss in %] gemäß Bedingungen der Mikrobiegeprüfung mit einer Maximalkraft von 50 N, einem Weg von max. 4800 μm, einem Probestück von 1 45 × b 10 × h 0,3 mm, einer Prüfgeschwindigkeit von 20 μm/s und einer Stützweite von 40 mm erhält und eine Korrosionsbeständigkeit durch eine Schichtdicke der Oxidschicht ab 5 μm.An electrical conductor treated according to this method has an oxide layer corresponding to a breakdown voltage safety of 30 to 60 V / layer thickness, a Marten hardness [HM] of> 2300, an increase in the wear resistance in comparison to conventional parameters, such as

• • a wear depth of approx. 100 μm to <70 μm according to the vibration wear test as well as
• A Ritzenergiedichte [J / mm ² ] of 0.03 to> 0.05 at normal forces of 2 N and from 0.45 to> 0.5 at normal forces of 50 N according to Ritzprüfversuch,

an improvement in ductility (crack sensitivity, cracking tendency) from 0.24 to 0.30 [% elongation at break] according to microbend test conditions with a maximum force of 50 N, a max. 4800 microns, a test piece of 1 45 × b 10 × h 0.3 mm, a test speed of 20 microns / s and a span of 40 mm receives and corrosion resistance by a layer thickness of the oxide layer from 5 microns.

This Head is to coils, windings or the like., Those properties require, processable.

such electrical conductors can be prepared with an anodic oxide layer, which in a Oxide layer thickness of approx. 6 μm and a thermal stress of about 2 h at 250 ° C a breakdown voltage safety of more than 300V.

With an oxide layer thickness of about 6 μm, an insulation resistance of> 200kΩ can be achieved, wherein the oxide layer has a porosity of 3 to 8 pores / nm ² .

Industrial Applicability

A Such electrical conductor with anodic oxide layer is z. For use in transformers on a removable carrier Coil or winding as metallic winding conductor with metal oxide layer to an array of electrically connected in series several coils and segments of a total winding with taps formed, taking in the overall winding at the entrance and at the exit lying coils with additional Layers of insulating material can be added.

in this connection are punctual additional insulations at the taps at the beginning / end the coil or the entire winding and between the coils as axial Fuse from coil to coil and in the overall winding an additional Isolation provided.

The additional Layers can from one of the thermal classes consist of corresponding foil.

The punctual additional insulation can also from one of the thermal classes consist of corresponding foil, wherein at the taps connections a non-anodized Al conductor may be provided.

at such applications is the production of an oxide layer for the conductor with high breakdown voltage security is an essential requirement.

Claims (22)

Anodic oxide layer for electrical conductors, in particular conductors made of aluminum in the form of bands or wires, wherein for the production of the oxide layer a) an electrolyte is used, which is oriented in its nature and composition to the reference of a sulfuric acid electrolyte and optionally in its Composition is variable, b) at least one selected type and shape of current and possibly their superimpositions are used and c) in a compacting after-treatment of the surface of the oxide layer, a substance is introduced, which is based on the reference of a recompression of an aggregate form of water, characterized in that the oxide layer d) produced a Marten hardness [HM e) an increase in wear resistance compared to conventional parameters, such as: • a wear depth of approx. 100 μm to <70 μm in accordance with the vibration wear test and • a ridge energy density [J / mm ² ] of 0.03 to> 0 , 05 at normal forces of 2 N and from 0.45 to> 0.5 at normal forces of 50 N according to scratch test, f) an improvement in ductility (crack sensitivity, cracking tendency) in comparison of 0.24 to 0.30 [elongation at 1st crack in%] according to the conditions of the microbending test with a maximum force of 50 N, a travel of max. 4800 microns, a test piece of l 45 × b 10 × h 0.3 mm, a test speed of 20 microns / s and a span of 40 mm receives, g) has a corrosion resistance by a layer thickness of the oxide layer from 5 microns and / or h ) at a thickness of about 6 microns and a thermal stress of about 2 h at 250 ° C a breakdown voltage of more than 300 V can be exposed. Anodic oxide layer for electrical conductors according to Claim 1, characterized in that the increased wear resistance of the oxide layer according to the scratch test test has a Ritzenergiedichte [J / mm ² ] of <0.6 at 50 N. Anodic oxide layer for electrical conductors according to claim 1 or 2, characterized in that the improved ductility from a Size of> 0.31. Method for producing an anodic oxide layer for electrical A ladder according to claim 1, comprising a) a bath with an electrolyte, in its nature and composition to the reference of a sulfuric acid electrolyte oriented and possibly variable in its composition, b) the feeding of at least one selected type and shape of current and possibly their overlays, c) the introduction of a color and dyeing followed by rinsing the oxide layer, d) a compacting treatment of the surface of Oxide layer with a substance to be introduced, such as hot water and e) compliance with a predetermined treatment temperature, marked by f) the use of an electrolyte comprising the constituents 15 ... 30 vol.% Sulfuric acid with an addition of 5 ... 30 g of oxalic acid / l of sulfuric acid, G) the introduction of an alternating current into sine, rectangular, triangular, or trapezoidal shape or a combination of these and with a Frequency up to 700 Hz, h) the use of a color as a substance before the compacting after-treatment. Method according to claim 4, characterized in that that the Electrolyte has a proportion of 20 vol.% Sulfuric acid. Method according to claim 4 or 5, characterized that the Electrolyte has a content of 15 g of oxalic acid / l sulfuric acid. Method according to one of claims 4 to 6, characterized by an enrichment of the electrolyte with Al particles in one Concentration in the range of about 3.5 g Al ... about 13 g Al / l electrolyte, the concentration depending on of the passage speed of the conductor in the bath is variable. Method according to one of claims 4 to 7, characterized that the introduced alternating current in the combination form trapezoid - sine used becomes. Method according to one of claims 4 to 8, characterized that the introduced alternating current in the combination sine, rectangle, trapezoid is used. Method according to one of claims 4 to 9, characterized that the introduced alternating current in alternating pulse shapes and / or pulse trains is used. Method according to one of claims 4 to 10, characterized that the introduced alternating current has a voltage of <50 V. Method according to one of claims 4 to 11, characterized by an anodization time of <120 s, depending on from the passage speed of the conductor in the bath and / or the amperage and / or the treatment interval is variable. Method according to one of Claims 4 to 12, characterized by the following steps: production of the required layer thickness, which can be realized approximately in proportion to the required breakdown voltage strength of the anodized conductor, introduction of the respective anodizing color into the bath and color treatment such as by dipping, rinsing, - Compressive treatment with hot water or steam to close the pores on the colored surface of the oxide layer. Method according to one of claims 4 to 13, characterized through the use of the color red. Method according to one of claims 4 to 13, characterized by using the color green. Method according to one of claims 4 to 15, characterized that the used current colors, such as so-called GTL-Oxalanfarben or Clariant colors are. Method according to one of claims 4 to 16, characterized through the use of software for the control of the Power sources for generating voltages at any frequency and shape. Method according to one of claims 4 to 17, characterized by using a bath for a dip dye Electrical conductor with anodic oxide layer according to one of claims 1 to 3 and according to the method treated according to one of claims 4 to 18, characterized in that this in its use as in coils, windings or the like. A) an oxide layer corresponding to a breakdown voltage of 30 to 60 B) has a Marten hardness [HM] of> 2300, c) an increase in the wear resistance in comparison to customary parameters such as • a wear depth of approx. 100 μm to <70 μm according to the vibrational wear test and • a ridge energy density [J / mm ² ] from 0.03 to> 0.05 at normal forces of 2 N and from 0.45 to> 0.5 at normal forces of 50 N according to scratch test, d) an improvement in ductility (crack sensitivity, cracking tendency) in comparison from 0.24 to 0.30 [elongation at the 1st crack in%] according to conditions of the microbending test with a maximum force of 50 N, a travel of max. 4800 .mu.m, a test piece of l 45 × b 10 × h 0.3 mm, a test speed of 20 .mu.m / s and a span of 40 mm and e) has a corrosion resistance by a layer thickness of the oxide layer from 5 microns. Electrical conductor with anodic oxide layer after Claim 19, characterized in that this at an oxide layer thickness of about 6 microns and a thermal stress of about 2 h at 250 ° C a breakdown voltage of has more than 300V. Electrical conductor with anodic oxide layer after Claim 19 or 20, characterized in that this at an oxide layer thickness of approx. 6 μm an insulation resistance of> 200 k Ω. Anodic oxide layer electrical conductor according to one of Claims 17 to 19, characterized in that its oxide layer has a porosity of 3 to 8 pores / nm ² .