EP0752012B1 - Process for producing magnetic steel sheets with a glass coating - Google Patents

Process for producing magnetic steel sheets with a glass coating Download PDF

Info

Publication number
EP0752012B1
EP0752012B1 EP95912252A EP95912252A EP0752012B1 EP 0752012 B1 EP0752012 B1 EP 0752012B1 EP 95912252 A EP95912252 A EP 95912252A EP 95912252 A EP95912252 A EP 95912252A EP 0752012 B1 EP0752012 B1 EP 0752012B1
Authority
EP
European Patent Office
Prior art keywords
annealing separator
additive
mgo
strip
annealing
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.)
Expired - Lifetime
Application number
EP95912252A
Other languages
German (de)
French (fr)
Other versions
EP0752012A1 (en
Inventor
Fritz Bölling
Brigitte Hammer
Thomas Dolle
Klaus Gehnen
Heiner Schrapers
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.)
EBG Gesellschaft fuer Elektromagnetische Werkstoffe
Original Assignee
EBG Gesellschaft fuer Elektromagnetische Werkstoffe
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 EBG Gesellschaft fuer Elektromagnetische Werkstoffe filed Critical EBG Gesellschaft fuer Elektromagnetische Werkstoffe
Publication of EP0752012A1 publication Critical patent/EP0752012A1/en
Application granted granted Critical
Publication of EP0752012B1 publication Critical patent/EP0752012B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1277—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties involving a particular surface treatment
    • C21D8/1283—Application of a separating or insulating coating
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/10—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of nickel or cobalt or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23D—ENAMELLING OF, OR APPLYING A VITREOUS LAYER TO, METALS
    • C23D5/00—Coating with enamels or vitreous layers
    • C23D5/02—Coating with enamels or vitreous layers by wet methods
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
    • H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
    • H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
    • H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
    • H01F1/14—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys
    • H01F1/16—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of sheets
    • H01F1/18—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials metals or alloys in the form of sheets with insulating coating

Definitions

  • the invention relates to a method for producing Electrical sheets, especially grain-oriented ones Electrical sheets, with an evenly adhering Glass film and with improved magnetic properties, in which the hot strip initially produced and possibly annealed except for the final cold strip thickness with at least one Cold rolling stage is cold rolled, then to the an annealing separator rolled to the final thickness is applied and dried and then the cold-rolled strip coated in a high-temperature annealing is subjected, with an integral part of the Glow separator an aqueous magnesium oxide (MgO) dispersion and the glow separator is additionally at least one Has additive.
  • MgO aqueous magnesium oxide
  • decarburization annealing is carried out after rolling to the final thickness.
  • the carbon is extracted from the material.
  • An oxide layer forms as a base layer on the strip surface, the essential components of which are silicon dioxide (SiO 2 ) and fayalite (Fe 2 SiO 4 ).
  • the strip is coated with a protective layer and subjected to a long-term annealing in the coil.
  • the adhesive protection layer is intended to prevent the individual coil turns from sticking together during long-term annealing and, on the other hand, to form an insulation layer (glass film) with the base layer on the strip surface.
  • the adhesive protection layer consists essentially of magnesium oxide (MgO).
  • the MgO is slurried in water in the form of a powder, applied to the belt and dried. During this process, part of the magnesium oxide reacts with the water to form magnesium hydroxide (Mg (OH) 2 ). The amount of water bound to magnesium hydroxide, based on the total amount of oxide powder, is called the loss on ignition.
  • Equation (I) shows the dehydration of the magnesium hydroxide, which starts at about 350 ° C. It is important for an optimally running process, both in terms of the insulation and the development of the magnetic properties, that the amount of water released is within certain limits.
  • the water humidifies the predominantly hydrogen-containing annealing atmosphere and thus sets a corresponding oxidation potential.
  • the annealing atmosphere must not be too dry because the glass film would be made too thin under such conditions. However, it must also not become too moist, because then it will be reoxidized too much and the glass film will have defects such as local flaking and poor adhesion.
  • additives to MgO powder were introduced to improve the formation of the insulation layer and the magnetic properties of the finished product.
  • These include titanium dioxide (TiO 2 ), boron compounds such as boron oxide (B 2 O 3 ) or sodium tetraborate (Na 2 B 4 O 7 ), as well as antimony compounds such as antimony sulfate (Sb 2 (SO 4 ) 3 ) in combination with a chloride, preferably antimony chloride SbCl 3 .
  • TiO 2 titanium dioxide
  • boron compounds such as boron oxide (B 2 O 3 ) or sodium tetraborate (Na 2 B 4 O 7 )
  • antimony compounds such as antimony sulfate (Sb 2 (SO 4 ) 3 ) in combination with a chloride, preferably antimony chloride SbCl 3 .
  • the additives used often also have disadvantages that reduce the product quality. Overall, the processing of such additives is cumbersome, since some of them have to be dissolved in previously
  • the invention is based on the object of measures to meet, especially by modifying the Glow separators to the insulation properties and at the same time the magnetic properties of the Finished product to improve further.
  • the Anti-adhesive layer can be applied more homogeneously quality-reducing phenomena, such as glow contours and to avoid local defects.
  • one should easy handling can be guaranteed and the cost, am Standard measured, kept low.
  • a readily water-soluble one Sodium phosphate compound is used.
  • a readily water soluble sodium phosphate compound and a finely dispersed oxidic aluminum compound Glow separator can be added.
  • the good water solubility of the sodium phosphate compound if necessary in combination with the finely dispersed distribution of the oxidic aluminum compound in the specified amounts ensure a homogeneous application of the adhesive protection, prevent coagulation within the aqueous Magnesium oxide dispersion and associated local Defects in the glass film and promote those in the Long-term annealing chemical reactions between the one on the belt surface Base layer and the adhesive protective layer to the glass film.
  • a stronger than the standard Glass film formation that the interaction between the Annealing atmosphere and the strips are positively influenced the magnetic properties of the electrical sheets improved.
  • a method with the generic measures has been known from EP 0 232 537 B1.
  • a titanium compound such as TiO 2
  • a boron compound such as B 2 O 3
  • a sulfur compound such as SrS
  • the MgO-based annealing separator is added to the MgO-based annealing separator as an additive, with the aim of improving the insulation properties, such as Adhesion and the appearance of the glass film to influence positively. This is achieved by hydrating the coating.
  • the magnetic properties were also improved by the addition of such additives.
  • JP-5-513 8021 describes a release agent based on MgO, which contains up to 50% by weight of Mg (OH) 2 and up to 5% by weight of Al (OH) 3 or Al (NO 3 ) 3 contains. It has been shown that the use of such a release agent for coating electrical sheets does not have an adverse effect on the magnetic properties of the product.
  • JP-5-247 661 describes a process for the production of grain-oriented silicon steels which are coated with a glass layer.
  • improvements in the magnetic properties and the surface properties of the coated steel are achieved by using release agent additives such as Sb 2 (SO 4 ) 3 , V 2 O s , SrS, Na 2 B 4 O 7 and Ca (H 2 PO 4 ) 2 .
  • the positive influence on which the invention is based the magnetic properties is characteristic of the sodium phosphates.
  • FIG. 1 shows the superiority of the samples produced by the method according to the invention with an MgO-based adhesive protection doped with sodium phosphate over other phosphate additives.
  • HGO high permeability grain oriented tape samples were coated with MgO + 6% TiO 2 + the listed additives, dried and annealed.
  • the sodium phosphates are readily water-soluble, allow thus an optimally homogeneous distribution within the Anti-adhesive layer.
  • Sodium phosphates in the present case in particular using the example of Sodium pyrophosphate decahydrate are reported both the magnetic properties polarization and Magnetic loss, as well Isolation training improved.
  • the Inhibitor test method is demonstrated that the Sodium pyrophosphate to a prematurely stronger one Glass film formation leads.
  • the inhibitor test stops Process in which, in principle, high annealing certain annealing temperatures are canceled and the Samples can be assessed magnetically. In the present case the insulation training was also assessed.
  • the magnetic properties of loss of magnetization P 1.7 and polarization J 800 were determined on the annealed strips.
  • the aluminum compounds used as a further additive in addition to the sodium phosphate compound are aluminum oxides or hydroxides of the form Al 2 O 3 , AlO (OH) 3 and AL (OH), the effect of which is fully exploited when the corresponding particle sizes are small. The effect is particularly evident when the compounds are added in the form of sols (very fine particles / water mixtures).
  • the average particle size should be less than 100 nm with the narrowest possible particle size distribution.
  • the addition of these aluminum compounds leads to a considerable improvement in loss, similar to the case with the addition of titanium dioxide.
  • the advantage of the aluminum compound as an additive over titanium dioxide is the lower dosage and the more homogeneous distribution of the particles. Another advantage lies in the fact that the aluminum compounds added also have the property of a ceramic binder, and the adhesive protective layer therefore adheres better to the tape.
  • Table 6 and Figure 3 show the influence of the selected aluminum compounds on the magnetic loss. Influence of different oxidic aluminum compounds on the magnetic properties and the glass film appearance
  • Boehmite AIO (OH) 0 0.5 2nd Glass film appearance
  • the effect of the above additives is optimized, if suitable combinations of additives are used. This also has positive effects in combination with additives already used, such as titanium dioxide, Antimony sulfate and sodium tetraborate achieved. Related to the slurry properties and thus the homogeneity of the MgO layer turns out to be a combination of one finely dispersed oxidic aluminum compound and one well water-soluble sodium phosphate as optimal because with these additives significantly fewer local defects to be observed.
  • the magnetic properties of loss of magnetization P 1.7 and polarization J 800 were determined on the annealed strips.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Electromagnetism (AREA)
  • Manufacturing & Machinery (AREA)
  • Power Engineering (AREA)
  • Dispersion Chemistry (AREA)
  • Chemical Treatment Of Metals (AREA)
  • Soft Magnetic Materials (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)
  • Laminated Bodies (AREA)
  • Glass Compositions (AREA)
  • Insulating Bodies (AREA)
  • Inorganic Insulating Materials (AREA)
  • Cell Separators (AREA)

Abstract

PCT No. PCT/EP95/01020 Sec. 371 Date Oct. 3, 1996 Sec. 102(e) Date Oct. 3, 1996 PCT Filed Mar. 18, 1995 PCT Pub. No. WO95/25820 PCT Pub. Date Sep. 28, 1995The invention comprises a method for producing electric sheets, in particular grain-oriented electric sheets, with an evenly well-adhering glass film and with improved magnetic properties, in which the hot rolled strip which is produced at first and is optionally annealed is cold-rolled up to an end thickness in one or several steps, thereafter an annealing separator is applied to the strip which is rolled up to the end thickness, and is dried, and therafter the cold strip thus coated is subjected to high-temperature annealing, with an important component of the annealing separator being a hydrous magnesium oxide (MgO) dispersion and the annealing separator being additionally provided with at least one additive. The characterizing feature of the invention is that a finely dispersed water-soluble sodium phosphate compound is used as at least one additive.

Description

Die Erfindung betrifft ein Verfahren zur Herstellung von Elektroblechen, insbesondere von kornorientierten Elektroblechen, mit einem gleichmäßigen gut haftenden Glasfilm und mit verbesserten magnetischen Eigenschaften, bei dem das zunächst erzeugte und ggf. geglühte Warmband bis auf die Kaltband-Enddicke mit mindestens einer Kaltwalzstufe kaltgewalzt wird, anschließend auf das bis auf die Enddicke gewalzte Band ein Glühseparator aufgebracht und getrocknet wird und im Anschluß daran das so beschichtete Kaltband einer Hochtemperaturglühung unterworfen wird, wobei wesentlicher Bestandteil des Glühseparators eine wäßrige Magnesiumoxid(MgO)-Dispersion ist und der Glühseparator zusätzlich mindestens ein Additiv aufweist.The invention relates to a method for producing Electrical sheets, especially grain-oriented ones Electrical sheets, with an evenly adhering Glass film and with improved magnetic properties, in which the hot strip initially produced and possibly annealed except for the final cold strip thickness with at least one Cold rolling stage is cold rolled, then to the an annealing separator rolled to the final thickness is applied and dried and then the cold-rolled strip coated in a high-temperature annealing is subjected, with an integral part of the Glow separator an aqueous magnesium oxide (MgO) dispersion and the glow separator is additionally at least one Has additive.

Bei der Fertigung von kornorientiertem Elektroblech wird nach dem Walzen auf Enddicke eine Entkohlungsglühung durchgeführt. Dabei wird dem Werkstoff der Kohlenstoff entzogen. An der Bandoberfläche bildet sich dabei eine Oxidschicht als Grundschicht, deren wesentliche Bestandteile Siliziumdioxid (SiO2) und Fayalit (Fe2SiO4) sind. Im Anschluß an die Entkohlungsglühung wird das Band mit einer Klebschutzschicht beschichtet und im Coil einer Langzeitglühung unterzogen. Die Klebschutzschicht soll zum einen das Zusammenkleben der einzelnen Coilwindungen während der Langzeitglühung verhindern und zum anderen mit der Grundschicht auf der Bandoberfläche eine Isolationsschicht (Glasfilm) bilden. Die Klebschutzschicht besteht im wesentlichen aus Magnesiumoxid (MgO). Das MgO wird in Form eines Pulvers in Wasser aufgeschlämmt, auf das Band aufgetragen und getrocknet. Bei diesem Vorgang reagiert ein Teil des Magnesiumoxides mit dem Wasser zu Magnesiumhydroxid (Mg(OH)2). Die an Magnesiumhydroxid gebundene Menge Wasser, bezogen auf die Gesamtoxidpulvermenge, wird als Glühverlust bezeichnet.In the production of grain-oriented electrical sheet, decarburization annealing is carried out after rolling to the final thickness. The carbon is extracted from the material. An oxide layer forms as a base layer on the strip surface, the essential components of which are silicon dioxide (SiO 2 ) and fayalite (Fe 2 SiO 4 ). Following the decarburization annealing, the strip is coated with a protective layer and subjected to a long-term annealing in the coil. On the one hand, the adhesive protection layer is intended to prevent the individual coil turns from sticking together during long-term annealing and, on the other hand, to form an insulation layer (glass film) with the base layer on the strip surface. The adhesive protection layer consists essentially of magnesium oxide (MgO). The MgO is slurried in water in the form of a powder, applied to the belt and dried. During this process, part of the magnesium oxide reacts with the water to form magnesium hydroxide (Mg (OH) 2 ). The amount of water bound to magnesium hydroxide, based on the total amount of oxide powder, is called the loss on ignition.

Die auf die Isolation bezogenen wesentlichen Abläufe und Reaktionen zwischen Bandoberfläche und Klebschutzschicht während der Langzeitglühung sind nachfolgend vereinfacht zusammengefaßt:The essential processes and related to isolation Reactions between the tape surface and the protective layer during long-term annealing are simplified below summarized:

Dehydratation des MagnesiumhydroxidesDehydration of the magnesium hydroxide

Mg(OH)2 → MgO + H2OMg (OH) 2 → MgO + H 2 O

GlasfilmbildungGlass film formation

Fe2SiO4 + 2 MgO → Mg2SiO4 + 2 FeO SiO2 + 2 MgO → Mg2SiO4 Gleichung (I) gibt die Dehydratation des Magnesiumhydroxides, die ab etwa 350 °C einsetzt, wieder. Dabei ist es für einen optimal ablaufenden Prozeß, sowohl auf die Isolation als auch auf die Ausbildung der magnetischen Eigenschaften bezogen, wichtig, daß die Menge freiwerdenden Wassers innerhalb bestimmter Grenzen liegt. Das Wasser feuchtet dabei die überwiegend Wasserstoff enthaltende Glühatmosphäre an und stellt damit ein entsprechendes Oxidationspotential ein. Die Glühatmosphäre darf nicht zu trocken sein, weil der Glasfilm unter derartigen Bedingungen zu dünn ausgebildet würde. Sie darf jedoch auch nicht zu feucht werden, weil dann zu stark nachoxidiert wird und der Glasfilm Fehlstellen wie lokales Abplatzen und eine schlechte Haftung aufweist. Fe 2 SiO 4 + 2 MgO → Mg 2 SiO 4 + 2 FeO SiO 2 + 2 MgO → Mg 2 SiO 4 Equation (I) shows the dehydration of the magnesium hydroxide, which starts at about 350 ° C. It is important for an optimally running process, both in terms of the insulation and the development of the magnetic properties, that the amount of water released is within certain limits. The water humidifies the predominantly hydrogen-containing annealing atmosphere and thus sets a corresponding oxidation potential. The annealing atmosphere must not be too dry because the glass film would be made too thin under such conditions. However, it must also not become too moist, because then it will be reoxidized too much and the glass film will have defects such as local flaking and poor adhesion.

In der Vergangenheit wurden eine Reihe von Zusätzen zum MgO-Pulver eingeführt, die die Ausbildung der Isolationsschicht und die magnetischen Eigenschaften des Fertigproduktes verbessern sollen. Dazu zählen Titandioxid (TiO2), Borverbindungen, wie Boroxid (B2O3) oder Natriumtetraborat (Na2B4O7), sowie Antimonverbindungen, wie z.B. Antimonsulfat (Sb2(SO4)3) in Kombination mit einem Chlorid, vorzugsweise Antimonchlorid SbCl3. Die eingesetzten Zusätze weisen neben den positiven Einflüssen auf die jeweiligen Zielgrößen allerdings häufig auch Nachteile auf, die die Produktqualität herabsetzen. Insgesamt ist die Verarbeitung derartiger Zusätze umständlich, da diese z.T. in vorher erhitztem Wasser gelöst werden müssen. Besonders bei den schwer wasserlöslichen Salzen Natriumtetraborat und insbesondere Antimonsulfat führen nicht gelöste, grobe Partikel zu Inhomogenitäten in der Klebschutzschicht und nachfolgend zu lokalen Fehlstellen im Glasfilm. Bei Antimonsulfat kommt hinzu, daß die Verbindung teuer ist und in die Kategorie der "minder giftigen" Substanzen eingestuft wird. Eine inhomogene Verteilung von Titandioxid im Klebschutz führt zu Fehlstellen im Glasfilm.In the past, a number of additives to MgO powder were introduced to improve the formation of the insulation layer and the magnetic properties of the finished product. These include titanium dioxide (TiO 2 ), boron compounds such as boron oxide (B 2 O 3 ) or sodium tetraborate (Na 2 B 4 O 7 ), as well as antimony compounds such as antimony sulfate (Sb 2 (SO 4 ) 3 ) in combination with a chloride, preferably antimony chloride SbCl 3 . In addition to the positive influences on the respective target values, the additives used often also have disadvantages that reduce the product quality. Overall, the processing of such additives is cumbersome, since some of them have to be dissolved in previously heated water. Especially with the poorly water-soluble salts sodium tetraborate and in particular antimony sulfate, undissolved, coarse particles lead to inhomogeneities in the adhesive protective layer and subsequently to local defects in the glass film. In addition, with antimony sulfate, the compound is expensive and is classified in the category of "less toxic" substances. An inhomogeneous distribution of titanium dioxide in the adhesive protection leads to defects in the glass film.

Der Erfindung liegt nun die Aufgabe zugrunde, Maßnahmen zu treffen, insbesondere durch Modifizierung des Glühseparators, um die Isolationseigenschaften und gleichzeitig die magnetischen Eigenschaften des Fertigprodukts weiter zu verbessern. Dabei soll die Klebschutzschicht homogener aufgetragen werden können, um qualitätsmindernde Erscheinungen, wie Glühkonturen und lokale Fehlstellen, zu vermeiden. Daneben soll eine einfache Handhabung gewährleistet sein und die Kosten, am Standard gemessen, niedrig gehalten werden. The invention is based on the object of measures to meet, especially by modifying the Glow separators to the insulation properties and at the same time the magnetic properties of the Finished product to improve further. Thereby the Anti-adhesive layer can be applied more homogeneously quality-reducing phenomena, such as glow contours and to avoid local defects. In addition, one should easy handling can be guaranteed and the cost, am Standard measured, kept low.

Zur Lösung dieser Aufgabe wird bei dem gattungsgemäßen Verfahren erfindungsgemäß vorgeschlagen, daß als mindestens ein Additiv eine gut wasserlösliche Natriumphosphatverbindung verwendet wird. Gemäß einer weiteren vorteilhaften Ausgestaltung des erfindungsgemäßen Verfahrens können als weitere Additive eine gut wasserlösliche Natriumphosphatverbindung und eine feindisperse oxidische Aluminiumverbindung dem Glühseparator zugesetzt werden.To solve this problem is the generic Method proposed according to the invention that as at least one additive is a readily water-soluble one Sodium phosphate compound is used. According to one another advantageous embodiment of the The inventive method can be used as further additives a readily water soluble sodium phosphate compound and a finely dispersed oxidic aluminum compound Glow separator can be added.

Die gute Wasserlöslichkeit der Natriumphosphatverbindung, ggfs. in Kombination mit der feindispersen Verteilung der oxidischen Aluminiumverbindung in den angegebenen Mengen gewährleisten eine homogene Auftragung des Klebschutzes, verhindern Koagulationen innerhalb der wäßrigen Magnesiumoxiddispersion und damit verbundene lokale Fehlstellen im Glasfilm und fördern die in der Langzeitglühung ablaufenden chemischen Reaktionen zwischen der auf der Bandoberfläche befindlichen Grundschicht und der Klebschutzschicht zum Glasfilm. Durch eine gegenüber dem Standard stärker einsetzende Glasfilmbildung, die die Wechselwirkung zwischen der Glühatmosphäre und den Bändern positiv beeinflußt, werden die magnetischen Eigenschaften der Elektrobleche verbessert.The good water solubility of the sodium phosphate compound, if necessary in combination with the finely dispersed distribution of the oxidic aluminum compound in the specified amounts ensure a homogeneous application of the adhesive protection, prevent coagulation within the aqueous Magnesium oxide dispersion and associated local Defects in the glass film and promote those in the Long-term annealing chemical reactions between the one on the belt surface Base layer and the adhesive protective layer to the glass film. By using a stronger than the standard Glass film formation that the interaction between the Annealing atmosphere and the strips are positively influenced the magnetic properties of the electrical sheets improved.

Ein Verfahren mit den gattungsgemäßen Maßnahmen ist aus der EP 0 232 537 B1 bekannt gewesen. Bei diesem bekannten Verfahren wird dem Glühseparator auf MgO-Basis als Additiv eine Titanverbindung, wie TiO2, und/oder eine Borverbindung, wie B2O3, und/oder eine Schwefelverbindung, wie SrS, mit dem Ziel zugesetzt, die Isolationseigenschaften, wie Haftung und das Aussehen des Glasfilms, positiv zu beeinflussen. Erreicht wird dies durch eine Hydratation der Beschichtung. Auch die magnetischen Eigenschaften wurden durch den Zusatz solcher Additive verbessert.A method with the generic measures has been known from EP 0 232 537 B1. In this known method, a titanium compound, such as TiO 2 , and / or a boron compound, such as B 2 O 3 , and / or a sulfur compound, such as SrS, is added to the MgO-based annealing separator as an additive, with the aim of improving the insulation properties, such as Adhesion and the appearance of the glass film to influence positively. This is achieved by hydrating the coating. The magnetic properties were also improved by the addition of such additives.

In der JP-5-513 8021 wird ein Trennmittel auf der Basis von MgO beschrieben, welches als Zusätze bis zu 50 Gew.-% Mg(OH)2 sowie bis zu 5 Gew.-% Al(OH)3 oder Al(NO3)3 enthält. Es wurde gezeigt, daß sich die Verwendung eines solchen Trennmittels zur Beschichtung von Elektroblechen nicht ungünstig auf die magnetischen Eigenschaften des Produkts auswirken.JP-5-513 8021 describes a release agent based on MgO, which contains up to 50% by weight of Mg (OH) 2 and up to 5% by weight of Al (OH) 3 or Al (NO 3 ) 3 contains. It has been shown that the use of such a release agent for coating electrical sheets does not have an adverse effect on the magnetic properties of the product.

Die JP-5-247 661 beschreibt ein Verfahren zur Herstellung von kornorientierten Siliciumstählen, die mit einer Glasschicht beschichtet sind. Bei diesem Verfahren werden durch Verwendung von Trennmitteladditiven wie Sb2(SO4)3, V2Os, SrS, Na2B4O7 und Ca(H2PO4)2 Verbesserungen der magnetischen Eigenschaften sowie der Obenflächenbeschaffenheit des beschichteten Stahls erzielt.JP-5-247 661 describes a process for the production of grain-oriented silicon steels which are coated with a glass layer. In this process, improvements in the magnetic properties and the surface properties of the coated steel are achieved by using release agent additives such as Sb 2 (SO 4 ) 3 , V 2 O s , SrS, Na 2 B 4 O 7 and Ca (H 2 PO 4 ) 2 .

Der der Erfindung zugrunde liegende positive Einfluß auf die magnetischen Eigenschaften ist charakteristisch für die Natriumphosphate.The positive influence on which the invention is based the magnetic properties is characteristic of the sodium phosphates.

Fig. 1 zeigt die Überlegenheit der nach dem erfindungsgemäßen Verfahren hergestellten Proben mit einem Natriumphosphat dotierten Klebschutz auf MgO-Basis gegenüber anderen Phosphatzusätzen. Dabei wurden HGO (high permeability grain oriented) Bandproben mit MgO + 6% TiO2 + den aufgeführten Zusätzen beschichtet, getrocknet und hochgeglüht.FIG. 1 shows the superiority of the samples produced by the method according to the invention with an MgO-based adhesive protection doped with sodium phosphate over other phosphate additives. HGO (high permeability grain oriented) tape samples were coated with MgO + 6% TiO 2 + the listed additives, dried and annealed.

Die Natriumphosphate sind gut wasserlöslich, ermöglichen damit eine optimal homogene Verteilung innerhalb der Klebschutzschicht. Durch die bevorzugte Verwendung der Natriumphosphate, vorliegend insbesondere am Beispiel des Natriumpyrophosphat Decahydrat ausgewiesen, werden sowohl die magnetischen Eigenschaften Polarisation und Ummagnetisierungsverlust, als auch die Isolationsausbildung verbessert. Im Inhibitortestverfahren wird nachgewiesen, daß das Natriumpyrophosphat zu einer vorzeitig stärkeren Glasfilmbildung führt. Der Inhibitortest stellt ein Verfahren dar, bei dem prinzipiell Hochglühungen bei bestimmten Glühtemperaturen abgebrochen werden und die Proben magnetisch beurteilt werden. Im vorliegenden Fall wurden zusätzlich die Isolationsausbildungen bewertet.The sodium phosphates are readily water-soluble, allow thus an optimally homogeneous distribution within the Anti-adhesive layer. Through the preferred use of the Sodium phosphates, in the present case in particular using the example of Sodium pyrophosphate decahydrate are reported both the magnetic properties polarization and Magnetic loss, as well Isolation training improved. in the Inhibitor test method is demonstrated that the Sodium pyrophosphate to a prematurely stronger one Glass film formation leads. The inhibitor test stops Process in which, in principle, high annealing certain annealing temperatures are canceled and the Samples can be assessed magnetically. In the present case the insulation training was also assessed.

Beispiel 1example 1

Jeweils 3 Bandproben aus 3 Bändern kornorientierten Elektroblechs der Güte HGO (high permeability grainoriented) und der Dicke 0,23 mm wurde zum einen mit einer wäßrigen Magnesiumoxiddispersion und zum anderen mit einer wäßrigen Magnesiumoxiddispersion, der 0,75 % Natriumpyrophosphat Decahydrat, bezogen auf 100 % Magnesiumoxid, zugesetzt wurde, beschichtet. Nachdem die Bandproben entsprechend dem Stand der Technik hochgeglüht wurden, wurden die magnetischen Kenngrößen bestimmt. Tabelle 1 gibt die magnetischen Kenngrößen Polarisation J800 und Ummagnetisierungsverlust P1,7 zum Vergleich der beiden Beschichtungen wieder. Einfluß von Natriumpyrophosphat als Zusatz zum MgO auf die magnetischen Eigenschaften Klebschutzzusammensetzung 100 % MgO 99,25 % MgO 0,75 % Na4P2O7*10H2O J800 in T 1,909 1,933 P1,7 in W/kg 1,118 0,995 3 strip samples each from 3 strips of grain-oriented electrical steel of the quality HGO (high permeability g rain or riented) and the thickness 0.23 mm were obtained on the one hand with an aqueous magnesium oxide dispersion and on the other hand with an aqueous magnesium oxide dispersion, the 0.75% sodium pyrophosphate decahydrate on 100% magnesium oxide, was coated. After the strip samples were annealed in accordance with the prior art, the magnetic parameters were determined. Table 1 shows the magnetic parameters polarization J 800 and magnetization loss P 1.7 for comparison of the two coatings. Influence of sodium pyrophosphate as an additive to MgO on the magnetic properties Anti-stick composition 100% MgO 99.25% MgO 0.75% Na 4 P 2 O7 * 10H 2 O J 800 in T 1,909 1,933 P 1.7 in W / kg 1,118 0.995

Beispiel 2Example 2

6 Bandproben aus kornorientiertem Elektroblech (HGO) der Nenndicke 0,23 mm, deren chemische Zusammensetzung willkürlich innerhalb des Analysenbereichs Si % C % Al % Mn % Sn % N % S % 3,17- 0,065- 0,025- 0,074- 0,118- 0,0077- 0,025- 3,29 0,070 0,026 0,080 0,120 0,0087 0,028 lagen, wurden nach dem Stand der Technik bis einschließlich der Entkohlung processiert, mit einem Trennmittel auf der Basis Magnesiumoxid und 6 Gew.-Teilen Titandioxid, bezogen auf 100 Gew.-Teile MgO, sowie den in Tabelle 2 aufgeführten Zusätzen beschichtet und anschließend entsprechend dem Stand der Technik hochgeglüht. An den hochgeglühten Bändern wurden die magnetischen Eigenschaften Ummagnetisierungsverlust P1,7 und Polarisation J800 bestimmt und das Glasfilmaussehen eingestuft. Tabelle 2 und Bild 2 stellen die Ergebnisse dar. Einfluß unterschiedlicher Natriumpyrophosphatkonzentrationen auf die magnetischen Eigenschaften und das Gladfilmaussehen Zusatz Bewertungsparameter MgO + 6%TiO2 + Zusatz in Gew.-Teile, bezogen auf 100 Gew.-Teile MgO Natriumpyrophosphat ecahydrat Na4P2O7*10H2O 0 0,5 1 2 Glasfilmassehen Glühkonturen frei von Glühkonturen frei von Glühkonturen fleckig P1,7 in W/kg 0,979 0,930 0,904 0,943 J800 in T 1,916 1,925 1,931 1,940 6 strip samples made of grain-oriented electrical steel (HGO) with a nominal thickness of 0.23 mm, the chemical composition of which is arbitrary within the analysis range Si% C% Al% Mn% Sn% N% S% 3.17- 0.065- 0.025- 0.074- 0.118- 0.0077- 0.025- 3.29 0.070 0.026 0.080 0.120 0.0087 0.028 were processed according to the state of the art up to and including decarburization, coated with a release agent based on magnesium oxide and 6 parts by weight of titanium dioxide, based on 100 parts by weight of MgO, and the additives listed in Table 2 and then in accordance with State of the art annealed. The magnetic properties of magnetization loss P 1.7 and polarization J 800 were determined on the annealed strips and the glass film appearance was classified. Table 2 and Figure 2 show the results. Influence of different sodium pyrophosphate concentrations on the magnetic properties and the smooth film appearance Addition of evaluation parameters MgO + 6% TiO 2 + addition in parts by weight, based on 100 parts by weight of MgO Sodium pyrophosphate ecahydrate Na 4 P 2 O 7 * 10H 2 O 0 0.5 1 2nd Glass film viewing Glow contours free of glow contours free of glow contours blotchy P 1.7 in W / kg 0.979 0.930 0.904 0.943 J 800 in T 1,916 1,925 1,931 1,940

Beispiel 3Example 3

29 Bandproben aus kornorientiertem Elektroblech (HGO) der Nenndicke 0,23 mm, deren chemische Zusammensetzung willkürlich innerhalb des Analysenbereichs Si % C % Al % Mn % Sn % N % S % 3,13- 0,063- 0,024- 0,072- 0,075- 0,0077- 0,020- 3,30 0,067 0,028 0,082 0,121 0,0090 0,027 lagen, wurden im Verfahren nach dem Stand der Technik bis einschließlich der Entkohlung processiert, mit einem Trennmittel auf der Basis Magnesiumoxid und 6 Gew.-Teilen Titandioxid, bezogen auf 100 Gew.-Teile MgO, sowie den in Tabelle 3 aufgeführten Zusätzen beschichtet und anschließend entsprechend dem Stand der Technik hochgeglüht. An den hochgeglühten Bändern wurden die magnetischen Eigenschaften Ummagnetisierungsverlust P1,7 und Polarisation J800 bestimmt und das Glasfilmaussehen eingestuft.

Figure 00090001
29 strip samples made of grain-oriented electrical steel (HGO) with a nominal thickness of 0.23 mm, the chemical composition of which is arbitrary within the analysis range Si% C% Al% Mn% Sn% N% S% 3.13- 0.063- 0.024- 0.072- 0.075- 0.0077- 0.020- 3.30 0.067 0.028 0.082 0.121 0.0090 0.027 were processed in the process according to the prior art up to and including decarburization, coated with a release agent based on magnesium oxide and 6 parts by weight of titanium dioxide, based on 100 parts by weight of MgO, and the additives listed in Table 3 and then annealed according to the state of the art. The magnetic properties of magnetization loss P 1.7 and polarization J 800 were determined on the annealed strips and the glass film appearance was classified.
Figure 00090001

Beispiel 4:Example 4:

Elektroblechproben der Dicke 0,29 mm und der chemischen Zusammensetzungen Si
% C
% Al
% Mn
% Sn
% N
% S
% Probe 1 3,13 0,061 0,020 0,070 0,075 0,0078 0,024 Probe 2 3,08 0,061 0,020 0,080 0,026 0,0076 0,023 wurden mit einer Beschichtung bestehend aus Magnesiumoxid und 6 % TiO2 und den in nachfolgender Tabelle aufgeführten Zusätzen versehen und hochgeglüht. Die Ergebnisse sind in Tabelle 4 zusammengefaßt.

Figure 00100001
Electrical sheet samples with a thickness of 0.29 mm and chemical compositions Si
% C.
% Al
% Mn
% Sn
% N
% S
% Sample 1 3.13 0.061 0.020 0.070 0.075 0.0078 0.024 Sample 2 3.08 0.061 0.020 0.080 0.026 0.0076 0.023 were provided with a coating consisting of magnesium oxide and 6% TiO 2 and the additives listed in the table below and annealed. The results are summarized in Table 4.
Figure 00100001

Beispiel 5:Example 5:

Bänder aus kornorientiertem Elektroblech der Nenndicke 0,23 mm, die im Verfahren nach dem Stand der Technik bis einschließlich der Entkohlung processiert wurden, wurden mit einem Trennmittel auf der Basis Magnesiumoxid und 6 Gew.-Teilen Titandioxid, bezogen auf 100 Gew.-Teile MgO, sowie den in Tabelle 5 aufgeführten Zusätzen beschichtet und anschließend entsprechend dem Stand der Technik hochgeglüht. An den hochgeglühten Bändern wurden die magnetischen Eigenschaften Ummagnetisierungsverlust P1,7 und Polarisation J800 bestimmt. Einfluß unterschiedlicher Na-Phosphate auf die magnetischen Eigenschaften Zusatz Bewertungsparameter MgO + 6%TiO2 +Zusatz in Gew.-Teile bezogen auf 100 Gew.-Teile MgO Natriumtetraborat Decahydrat NA2B4O7 *10H2O 0 0,3 0 0 0 0 Natriumpyrophosphat Decahydrat Na4P2O7*10H2O 0 0 1,5 0 0 0 Di-Natriumhydrogen phosphat Na2HPO4*2H2O 0 0 0 1,2 0 0 Tri-Natriumphosphat Na3PO4*12H2O 0 0 0 0 2,55 0 Natriumammonium hydrogenphosphat NaNH4HPO4 0 0 0 0 0 1,4 Antimonsulfat Sb2(SO4)3 0 0,1 0 0 0 0 P1,7 in W/kg 0,983 0,942 0,937 0 937 0,992 0,949 J800 in T 1,918 1,926 1,932 1,925 1,927 1,916 Strips made of grain-oriented electrical sheet with a nominal thickness of 0.23 mm, which were processed in the process according to the prior art up to and including decarburization, were coated with a release agent based on magnesium oxide and 6 parts by weight of titanium dioxide, based on 100 parts by weight of MgO , and the additives listed in Table 5 and then annealed according to the state of the art. The magnetic properties of loss of magnetization P 1.7 and polarization J 800 were determined on the annealed strips. Influence of different Na phosphates on the magnetic properties Addition of evaluation parameters MgO + 6% TiO 2 + addition in parts by weight based on 100 parts by weight of MgO Sodium tetraborate decahydrate NA 2 B 4 O 7 * 10H 2 O 0 0.3 0 0 0 0 Sodium pyrophosphate decahydrate Na 4 P 2 O 7 * 10H 2 O 0 0 1.5 0 0 0 Disodium hydrogen phosphate Na 2 HPO 4 * 2H 2 O 0 0 0 1.2 0 0 Tri-sodium phosphate Na 3 PO 4 * 12H 2 O 0 0 0 0 2.55 0 Sodium ammonium hydrogen phosphate NaNH 4 HPO 4 0 0 0 0 0 1.4 Antimony sulfate Sb 2 (SO 4 ) 3 0 0.1 0 0 0 0 P 1.7 in W / kg 0.983 0.942 0.937 0 937 0.992 0.949 J 800 in T 1,918 1,926 1,932 1,925 1,927 1,916

Die als weiteres Additiv neben der Natriumphosphatverbindung verwendeten Aluminiumverbindungen sind Aluminiumoxide bzw. -hydroxide der Form Al2O3, AlO(OH)3 und AL(OH) deren Wirkung dann voll ausgeschöpft wird, wenn die entsprechenden Partikelgrößen klein sind. Die Wirkung zeigt sich besonders deutlich, wenn die Verbindungen in Form von Solen (feinste Partikel/Wasser-Gemische) zugegeben werden. Die Partikelgröße sollte im Mittel kleiner als 100nm bei einer möglichst engen Partikelgrößenverteilung sein. Die Zugabe dieser Aluminiumverbindungen führt zu einer erheblichen Verlustverbesserung, ähnlich wie es bei der Zugabe von Titandioxid der Fall ist. Der Vorteil der Aluminiumverbindung als Zusatz gegenüber Titandioxid sind die geringer dosierten Zugaben und die homogenere Verteilung der Partikel. Ein weiterer Vorteil liegt in der Tatsache, daß die zugegebenen Aluminiumverbindungen auch die Eigenschaft eines keramischen Binders haben, die Klebschutzschicht demnach besser am Band haftet.The aluminum compounds used as a further additive in addition to the sodium phosphate compound are aluminum oxides or hydroxides of the form Al 2 O 3 , AlO (OH) 3 and AL (OH), the effect of which is fully exploited when the corresponding particle sizes are small. The effect is particularly evident when the compounds are added in the form of sols (very fine particles / water mixtures). The average particle size should be less than 100 nm with the narrowest possible particle size distribution. The addition of these aluminum compounds leads to a considerable improvement in loss, similar to the case with the addition of titanium dioxide. The advantage of the aluminum compound as an additive over titanium dioxide is the lower dosage and the more homogeneous distribution of the particles. Another advantage lies in the fact that the aluminum compounds added also have the property of a ceramic binder, and the adhesive protective layer therefore adheres better to the tape.

Beispiel 6 (nur zur Erläuterung, außerhalb der Erfindung) Example 6 (for illustration only, outside the invention)

4 Bandproben aus kornorientiertem Elektroblech der Nenndicke 0,23 mm, deren chemische Zusammensetzung willkürlich innerhalb des Analysenbereichs Si
% C
% Al
% Mn
% Sn
% N
% S
% 3,23- 0,065- 0,025- 0,073- 0,117- 0,0084- 0,021- 3,29 0,073 0,028 0,077 0,119 0,0090 0,027 lagen, wurden nach dem Stand der Technik bis einschließlich der Entkohlung processiert, mit einem Trennmittel auf der Basis Magnesiumoxid, sowie den in Tabelle 6 aufgeführten Zusätzen beschichtet und anschließend entsprechend dem Stand der Technik hochgeglüht. An den hochgeglühten Bändern wurden die magnetischen Eigenschaften Ummagnetisierungsverlust P1,7 und Polarisation J800 bestimmt und das Glasfilmaussehen eingestuft. Tabelle 6 und Bild 3 zeigen den Einfluß der ausgewählten Aluminiumverbindungen auf den Ummagnetisierungsverlust. Einfluß unterschiedlicher oxidischer Aluminiumverbindungen auf die magnetischen Eigenschaften und das Glasfilmaussehen Zusatz Bewertungsparameter MgO+Zusatz in Gew.-Teile, bezogen auf 100 Gew.-Teile MgO Aluminiumoxid Al2O3 0 0,5 2 4 Glasfilmaussehen Glühkonturen gleichmäßig zu dünn zu dünn P1,7 in W/kg 0,968 0,944 0,914 0,931 J800 in T 1,928 1,924 1,925 1,928 Böhmit AIO(OH) 0 0,5 2 Glasfilmaussehen Glühkonturen gleichmäßig zu dünn - P1,7 in W/kg 0,968 0,906 0,917 J800 in T 1,928 1,931 1,928 Vergleich MgO+ Zusatz Titandioxid in Gew.-Teile, bezogen auf MgO Titandioxid 0 6 Glasfilmaussehen Glühkonturen Glühkonturen P1,7 in W/kg 0,968 0,913 J800 in T 1,928 1,919 4 strip samples made of grain-oriented electrical steel with a nominal thickness of 0.23 mm, the chemical composition of which is arbitrary within the analysis range Si
% C.
% Al
% Mn
% Sn
% N
% S
% 3.23- 0.065- 0.025- 0.073- 0.117- 0.0084- 0.021- 3.29 0.073 0.028 0.077 0.119 0.0090 0.027 were processed according to the state of the art up to and including decarburization, coated with a releasing agent based on magnesium oxide and the additives listed in Table 6 and then annealed in accordance with the prior art. The magnetic properties of magnetization loss P 1.7 and polarization J 800 were determined on the annealed strips and the glass film appearance was classified. Table 6 and Figure 3 show the influence of the selected aluminum compounds on the magnetic loss. Influence of different oxidic aluminum compounds on the magnetic properties and the glass film appearance Addition of evaluation parameters MgO + addition in parts by weight, based on 100 parts by weight of MgO Alumina Al 2 O 3 0 0.5 2nd 4th Glass film appearance Glow contours evenly too thin too thin P 1.7 in W / kg 0.968 0.944 0.914 0.931 J 800 in T 1,928 1,924 1,925 1,928 Boehmite AIO (OH) 0 0.5 2nd Glass film appearance Glow contours evenly too thin - P 1.7 in W / kg 0.968 0.906 0.917 J 800 in T 1,928 1,931 1,928 Comparison of MgO + addition of titanium dioxide in parts by weight, based on MgO Titanium dioxide 0 6 Glass film appearance Glow contours Glow contours P 1.7 in W / kg 0.968 0.913 J 800 in T 1,928 1,919

Die Wirkung der obengenannten Zusätze wird optimiert, wenn geeignete Kombinationen von Zusätzen benutzt werden. Dabei werden auch positive Effekte in Kombination mit bereits eingesetzten Zusätzen, wie Titandioxid, Antimonsulfat und Natriumtetraborat erzielt. Bezogen auf die Slurryeigenschaften und damit auf die Homogenität der MgO-Schicht erweist sich eine Kombination einer feindispersen oxidischen Aluminiumverbindung und eines gut wasserlöslichen Natriumphosphates als optimal, da mit diesen Zusätzen deutlich weniger lokale Fehlstellen beobachtet werden.The effect of the above additives is optimized, if suitable combinations of additives are used. This also has positive effects in combination with additives already used, such as titanium dioxide, Antimony sulfate and sodium tetraborate achieved. Related to the slurry properties and thus the homogeneity of the MgO layer turns out to be a combination of one finely dispersed oxidic aluminum compound and one well water-soluble sodium phosphate as optimal because with these additives significantly fewer local defects to be observed.

Beispiel 7:Example 7:

Proben aus einem Band aus kornorientiertem Elektroblech der Nenndicke 0,23 mm, die im Verfahren nach dem Stand der Technik bis einschließlich der Entkohlung processiert wurden, wurden mit einem Trennmittel auf der Basis Magnesiumoxid und den in Tabelle 7 aufgeführten Zusätzen beschichtet und anschließend entsprechend dem Stand der Technik hochgeglüht. An den hochgeglühten Bändern wurden die magnetischen Eigenschaften Ummagnetisierungsverlust P1,7 und Polarisation J800 bestimmt.

Figure 00150001
Samples from a strip of grain-oriented electrical sheet with a nominal thickness of 0.23 mm, which were processed in the process according to the prior art up to and including decarburization, were coated with a release agent based on magnesium oxide and the additives listed in Table 7 and then in accordance with the status of technology glowed. The magnetic properties of loss of magnetization P 1.7 and polarization J 800 were determined on the annealed strips.
Figure 00150001

Claims (7)

  1. A method for producing electric sheets, in particular grain-oriented electric sheets, with an evenly well-adhering glass film and with improved magnetic properties, in which the hot rolled strip which is produced at first and is optionally annealed is cold-rolled up to the end thickness of the cold strip with at least one cold rolling stage, thereafter an annealing separator is applied to the strip which is rolled up to the end thickness, and is dried, and thereafter the cold strip which is thus coated is subjected to a high-temperature annealing, with a hydrous magnesium oxide (MgO) dispersion being an important component of the annealing separator and the annealing separator being provided with at least one additive, characterised in that a favourably water-soluble sodium phosphate compound is used as at least one additive.
  2. A method according to claim 1, characterised in that at least two additives are used, namely a favourably water-soluble sodium phosphate compound and a finely dispersed oxidic aluminium compound.
  3. A method according to claim 1 or 2, characterised in that 0.05 to 4.0 % sodium phosphate, relating to the MgO quantity, is added to the annealing separator as additive.
  4. A method according to claim 1 or 2, characterised in that 0.3 to 1.5 % of sodium pyrophosphate decahydrate, relating to the MgO quantity, is added to the annealing separator as additive.
  5. A method according to claims 2, 3 or 4, characterised in that 0.05 to 4.0 % of the finely dispersed oxidic aluminium compound, relating to the MgO quantity, is added to the annealing separator as additive.
  6. A method according to claims 2, 3, 4 or 5, characterised in that the oxidic aluminium compound is used with a particle size below 100 nm.
  7. A method according to claim 1 to 6, characterised in that further additives such as titanium dioxide, boron oxide, sodium tetraborate, antimony sulphate, metal chloride, preferably antimony chloride, are added to the annealing separator.
EP95912252A 1994-03-22 1995-03-18 Process for producing magnetic steel sheets with a glass coating Expired - Lifetime EP0752012B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4409691 1994-03-22
DE4409691A DE4409691A1 (en) 1994-03-22 1994-03-22 Process for the production of electrical sheets with a glass coating
PCT/EP1995/001020 WO1995025820A1 (en) 1994-03-22 1995-03-18 Process for producing magnetic steel sheets with a glass coating

Publications (2)

Publication Number Publication Date
EP0752012A1 EP0752012A1 (en) 1997-01-08
EP0752012B1 true EP0752012B1 (en) 1998-08-26

Family

ID=6513410

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95912252A Expired - Lifetime EP0752012B1 (en) 1994-03-22 1995-03-18 Process for producing magnetic steel sheets with a glass coating

Country Status (10)

Country Link
US (1) US5863356A (en)
EP (1) EP0752012B1 (en)
JP (1) JP3730254B2 (en)
KR (1) KR100367985B1 (en)
AT (1) ATE170226T1 (en)
CZ (1) CZ292216B6 (en)
DE (2) DE4409691A1 (en)
PL (1) PL178890B1 (en)
RU (1) RU2139945C1 (en)
WO (1) WO1995025820A1 (en)

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3475258B2 (en) * 1994-05-23 2003-12-08 株式会社海水化学研究所 Ceramic film forming agent and method for producing the same
DE19750066C1 (en) * 1997-11-12 1999-08-05 Ebg Elektromagnet Werkstoffe Process for coating electrical steel strips with an annealing separator
DE102004014596A1 (en) * 2004-03-23 2005-10-27 Trithor Gmbh Non-stick coating for the production of composite material wires
JP5633178B2 (en) * 2010-04-27 2014-12-03 Ｊｆｅスチール株式会社 Annealing separator for grain-oriented electrical steel sheet
DE102010038038A1 (en) * 2010-10-07 2012-04-12 Thyssenkrupp Electrical Steel Gmbh Process for producing an insulation coating on a grain-oriented electro-steel flat product and electro-flat steel product coated with such an insulation coating
CN102453793B (en) * 2010-10-25 2013-09-25 宝山钢铁股份有限公司 Annealing isolation agent used for preparing mirror surface-oriented silicon steel with excellent magnetic property
KR101453235B1 (en) * 2011-01-12 2014-10-22 신닛테츠스미킨 카부시키카이샤 Grain-oriented magnetic steel sheet and process for manufacturing same
JP5360272B2 (en) * 2011-08-18 2013-12-04 Ｊｆｅスチール株式会社 Method for producing grain-oriented electrical steel sheet
CN103857827B (en) * 2011-10-04 2016-01-20 杰富意钢铁株式会社 Orientation electromagnetic steel plate annealing separation agent
DE102015114358B4 (en) 2015-08-28 2017-04-13 Thyssenkrupp Electrical Steel Gmbh Method for producing a grain-oriented electrical strip and grain-oriented electrical strip
KR101909218B1 (en) * 2016-12-21 2018-10-17 주식회사 포스코 Annealing separating agent composition for grain oriented electrical steel sheet, grain oriented electrical steel sheet, and method for manufacturing grain oriented electrical steel sheet
JP6939767B2 (en) 2018-12-27 2021-09-22 Ｊｆｅスチール株式会社 Annealing separator for grain-oriented electrical steel sheets and manufacturing method of grain-oriented electrical steel sheets
JP6939766B2 (en) * 2018-12-27 2021-09-22 Ｊｆｅスチール株式会社 Annealing separator for grain-oriented electrical steel sheets and manufacturing method of grain-oriented electrical steel sheets
CN111906142B (en) * 2020-06-24 2022-08-16 浙江博星工贸有限公司 Process for controlling mechanical property of cold-rolled stainless steel strip
CN114014529B (en) * 2021-12-17 2023-02-21 中国建筑材料科学研究总院有限公司 Isolating agent for fire polishing of borosilicate glass beads
CN114854960B (en) * 2022-03-30 2023-09-05 武汉钢铁有限公司 Annealing isolating agent for reducing surface defects of oriented silicon steel and use method thereof

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3151000A (en) * 1959-08-28 1964-09-29 Hooker Chemical Corp Method of applying highly heat resistant protective coatings to metallic surfaces
US3151997A (en) * 1961-09-29 1964-10-06 United States Steel Corp Separating-medium coating for preparation of electrical steel strip for annealing
US3615918A (en) * 1969-03-28 1971-10-26 Armco Steel Corp Method of annealing with a magnesia separator containing a decomposable phosphate
SU569653A1 (en) * 1976-01-04 1977-08-25 Уральский научно-исследовательский институт черных металлов Composition for thermoinsulating coatings
US4160681A (en) * 1977-12-27 1979-07-10 Allegheny Ludlum Industries, Inc. Silicon steel and processing therefore
JPS55138021A (en) * 1979-04-11 1980-10-28 Nippon Steel Corp Manufacture of annealing separation agent for electromagnetic steel plate
IT1127263B (en) * 1978-11-28 1986-05-21 Nippon Steel Corp SEPARATION SUBSTANCE TO BE USED IN THE ANNEALING PHASE OF ORIENTED GRAINS OF SILICON STEEL
GB2130241B (en) * 1982-09-24 1986-01-15 Nippon Steel Corp Method for producing a grain-oriented electrical steel sheet having a high magnetic flux density
JPS62156226A (en) * 1985-12-27 1987-07-11 Nippon Steel Corp Production of grain oriented electrical steel sheet having uniform glass film and excellent magnetic characteristic
US4909864A (en) * 1986-09-16 1990-03-20 Kawasaki Steel Corp. Method of producing extra-low iron loss grain oriented silicon steel sheets
JPH0649949B2 (en) * 1988-10-18 1994-06-29 新日本製鐵株式会社 Method for producing grain-oriented electrical steel sheet having punching properties and metallic luster with excellent magnetic properties
DE69015060T2 (en) * 1989-09-08 1995-04-27 Armco Inc Magnesium oxide coating for electrical sheets and coating processes.
JPH05247661A (en) * 1992-03-04 1993-09-24 Nippon Steel Corp Production of grain oriented silicon steel sheet having uniform glass film and excellent in magnetic property

Also Published As

Publication number Publication date
US5863356A (en) 1999-01-26
CZ292216B6 (en) 2003-08-13
KR100367985B1 (en) 2003-08-02
DE4409691A1 (en) 1995-09-28
CZ273896A3 (en) 1997-04-16
JPH09510503A (en) 1997-10-21
KR970701795A (en) 1997-04-12
PL178890B1 (en) 2000-06-30
ATE170226T1 (en) 1998-09-15
JP3730254B2 (en) 2005-12-21
PL316139A1 (en) 1996-12-23
RU2139945C1 (en) 1999-10-20
EP0752012A1 (en) 1997-01-08
WO1995025820A1 (en) 1995-09-28
DE59503345D1 (en) 1998-10-01

Similar Documents

Publication Publication Date Title
EP0752012B1 (en) Process for producing magnetic steel sheets with a glass coating
DE2637591C3 (en) Method of forming a heat-resistant, insulating coating on an oriented silicon steel sheet
EP0090241B1 (en) Thermostable iron oxide pigments
DE2450850A1 (en) METHOD AND MEANS OF FORMING AN INSULATING COATING ON AN ORIENTED SI STEEL SHEET
DE60020316T2 (en) Oriented electromagnetic steel with excellent coating capability and method of manufacture
DE3229295C2 (en) Grain-oriented electrical steel sheet and process for its manufacture
DE2014544C3 (en) A method of applying an insulating glass coating to the surface of a silicon steel material
DE2752803B2 (en) Aqueous coating agent based on colloidal silicic acid anhydride
DE112015004097T5 (en) MAGNETIC POWDER CORE, MAGNETIC POWDER POWDER, AND METHOD FOR THE PRODUCTION THEREOF
DE102008008781A1 (en) Method for producing a grain-oriented electrical strip
EP2652172A1 (en) Method for producing a grain-oriented electric strip
DE2062290B2 (en) METHOD FOR CREATING AN ELECTRICALLY INSULATING MGO-CONTAINING LAYER ON SILICON STEEL SHEETS
DE2947945A1 (en) GLOW SEPARATOR FOR CORNORIENTED SILICON STEEL TAPES
DE3440344A1 (en) Process for producing grain-oriented electric steel sheet having improved magnetic properties and improved glass film properties
EP0199975A2 (en) Red iron oxide pigments having improved colouring properties, process for their manufacture and their use
DE1954773A1 (en) Process for the production of oriented magnetic steel sheets with low iron losses
DE3218821C2 (en) Stable slurry of inactive magnesia and process for its preparation
DE2810155A1 (en) COATING SOLUTION FOR ELECTRIC STEEL SHEETS
EP4027358B1 (en) Soft magnetic alloy and method for producing a soft magnetic alloy
WO2019110777A1 (en) Chromium- and phosphate-free coating for electrically insulating an electric strip
EP3746573A1 (en) Electrical steel strip that can be but doesn't have to be reannealed
DE4293604C2 (en) Soft magnetic steel material and process for its manufacture
DE2856324A1 (en) SILICON STEEL AND METHOD FOR PROCESSING IT
DE3841748A1 (en) ALLOY WITH HIGHLY SATURATED MAGNETIC FLOW DENSITY
EP3693496A1 (en) Aqueous composition for coating grain-oriented steel

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: 19960821

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

17Q First examination report despatched

Effective date: 19970402

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE

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

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: 19980826

Ref country code: GR

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

Effective date: 19980826

Ref country code: ES

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 19980826

REF Corresponds to:

Ref document number: 170226

Country of ref document: AT

Date of ref document: 19980915

Kind code of ref document: T

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

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

Effective date: 19980827

REF Corresponds to:

Ref document number: 59503345

Country of ref document: DE

Date of ref document: 19981001

ET Fr: translation filed
REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: GERMAN

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: 19981126

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: 19981126

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: 19981126

NLV1 Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act
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: 19990318

Ref country code: AT

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

Effective date: 19990318

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

Ref country code: LI

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

Effective date: 19990331

Ref country code: CH

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

Effective date: 19990331

Ref country code: BE

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

Effective date: 19990331

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

Ref country code: IE

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

Effective date: 19990504

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
BERE Be: lapsed

Owner name: EBG G.- FUR ELEKTROMAGNETISCHE WERKSTOFFE M.B.H.

Effective date: 19990331

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: 19990930

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

REG Reference to a national code

Ref country code: FR

Ref legal event code: CD

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

Ref country code: DE

Payment date: 20140319

Year of fee payment: 20

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

Ref country code: IT

Payment date: 20140321

Year of fee payment: 20

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

Ref country code: GB

Payment date: 20140318

Year of fee payment: 20

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

Ref country code: FR

Payment date: 20140318

Year of fee payment: 20

REG Reference to a national code

Ref country code: DE

Ref legal event code: R071

Ref document number: 59503345

Country of ref document: DE

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Expiry date: 20150317

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 EXPIRATION OF PROTECTION

Effective date: 20150317