EP0710732A1 - Method for hot-dip coating without alloying a interstitial free steel plate - Google Patents

Method for hot-dip coating without alloying a interstitial free steel plate Download PDF

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Publication number
EP0710732A1
EP0710732A1 EP95402327A EP95402327A EP0710732A1 EP 0710732 A1 EP0710732 A1 EP 0710732A1 EP 95402327 A EP95402327 A EP 95402327A EP 95402327 A EP95402327 A EP 95402327A EP 0710732 A1 EP0710732 A1 EP 0710732A1
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EP
European Patent Office
Prior art keywords
sheet
alloy
coating
steel
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP95402327A
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German (de)
French (fr)
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EP0710732B1 (en
Inventor
Armelle Jouet
Louis Guillot
Vincent Cholet
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Sollac SA
Original Assignee
Sollac SA
Lorraine de Laminage Continu SA SOLLAC
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Publication of EP0710732A1 publication Critical patent/EP0710732A1/en
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Classifications

    • 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
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C23C2/28—Thermal after-treatment, e.g. treatment in oil bath
    • 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
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C23C2/28—Thermal after-treatment, e.g. treatment in oil bath
    • C23C2/29—Cooling or quenching

Definitions

  • the invention relates to a coating method, by soaking and without alloy, of a sheet of steel with low interstitial by a metallic layer to aluminum or zinc base and the use of this coated sheet for prepare said strip for enameling or painting.
  • IF Interstitial Free
  • these steel shades contain proportions sufficiently low interstitial elements, in particular carbon and nitrogen, which avoids any risk of supersaturation of these elements in steel.
  • IF steel sheets are widespread, in particular because that these sheets do not present a risk of metallurgical aging.
  • Metallurgical aging is particularly troublesome in the case of sheets coated by dipping, in particular intended for enamelling or for painting.
  • a treatment is generally also carried out thermal alloy after quenching at a sufficiently high temperature to trigger the alliance, said temperature often being higher than the coating melting temperature.
  • the annealing treatment and alloying treatment help to eliminate carbon and nitrogen oversaturations in steel, and therefore to be freed problems inherent in metallurgical aging.
  • the invention relates to IF steel sheets for which such metallurgical aging treatment is, of course, never considered after a dip coating without alloying.
  • the invention relates to coatings based on zinc or aluminum on these IF steel sheets.
  • the layer of enamel deposited on said sheet coated may have a matt, satin or shiny character.
  • the invention aims to improve the surface appearance of an IF sheet coated by dipping, in particular with a metallic base layer aluminum or zinc, after enameling or after painting or after simple aging.
  • the subject of the invention is a coating process, by quenching and without alloy, of a sheet of steel with low interstitial by a metallic layer to aluminum or zinc base according to which said sheet is prepared for the coating, soaking said sheet in a bath of molten metal, extracting bath said sheet and solidifies the metallic layer entrained on the surface of said sheet, in particular by rapid cooling, characterized in that that, immediately after solidification of said metal layer, subjects said sheet to a rapid heat treatment of a shorter duration 5 minutes including a rapid heating step and a rapid cooling to room temperature, said rapid heating being adapted to bring the surface of said sheet to a temperature higher than 300 ° C but lower than the alloying temperature between said sheet metal and said metal layer.
  • the invention also relates to the use of such a coated sheet by dipping, in particular with a layer of aluminum or aluminum alloy, for an enamel coating, in particular an enamel having a surface brilliant.
  • the invention also relates to the use of such a coated sheet by dipping, in particular with a layer of zinc, for a coating of paint, especially paint that requires cooking at a temperature above 100 ° C.
  • the installation of continuous coating by dipping a strip metal comprises means for preparing the strip, means soaking the strip in a molten metal bath, means for solidification and dewatering of metallic layer and means of rapid heat treatment arranged in cascade along a path continuous scrolling of said strip.
  • the means for preparing the strip, the means for soaking the strip in a bath of molten metal and the solidification means and of metallic layer are known in themselves for the dip coating of metal strips.
  • the means for preparing the strip include in particular means for preparing the surface of the strip and means for recrystallization of the steel from the strip.
  • the means for surface preparation of the strip comprise a burning chamber with open flame burners oriented towards said tape scroll path.
  • the recrystallization means comprise a thermal enclosure whose atmosphere is confined and controllable.
  • the dipping means comprise a crucible for dipping the strip to contain a bath of molten metal.
  • the solidification and wringing means include ramps of gas blowing at room temperature oriented towards the tape scrolling.
  • the heat treatment means include means for heating and cooling means.
  • the heating means are in the form of a tunnel equipped with infrared radiation ramps oriented towards the path tape scrolling.
  • heating means can be used without losing of the present invention, in particular means of heating by induction.
  • the cooling means include ejection ramps gas or liquid oriented toward the tape running path.
  • the duration of the rapid heat treatment is less than 2 minutes.
  • the radiation power of the infrared ramps of the tunnel heating and the length of said tunnel are adapted in a known manner in itself so that the temperature of the surface of the strip is brought up at a temperature above 300 ° C but below the temperature of alloy between said sheet and said metal layer.
  • said strip surface temperature is preferably between 550 ° C and 625 ° C.
  • said surface temperature of the strip is preferably between 320 ° C and 390 ° C.
  • said strip surface temperature is preferably between 390 ° C and 550 ° C.
  • the gas flow rate of the ejection ramps of the cooling means and the number of ramps along the tape running path are adapted in a manner known per se to cool the surface of the tape at room temperature.
  • the Applicant has also found that surface defects no longer appear after aging of an IF steel sheet, thus coated by dipping, in particular zinc or a zinc-based alloy.
  • the purpose of this test is to illustrate the method according to the invention of dip coating of an IF steel strip with a layer of alloy aluminum.
  • the aluminum alloy to be deposited contains, by weight, 90% aluminum and 10% silicon and melts at a temperature of about 680 ° C.
  • the length of the tunnel of heating means for treatment thermal according to the invention is about 80 m.
  • the aluminum alloy coating thus obtained has good adhesion to the steel substrate and a homogeneous surface appearance.
  • the purpose of this test is to illustrate the improvement of the surface condition of a coated sheet according to the invention then enamelled to obtain a surface brilliant.
  • An IF steel strip coated under the same conditions is prepared than in test no. 1, with the difference that the coated strip is cooled to room temperature immediately after spinning and solidification of the coating layer, without passing through the rapid heating tunnel and a sheet blank A is cut from the strip obtained.
  • a sheet blank B is cut from the coated strip from test # 1.
  • the enamel used can have the following composition: Si02: 27% - TiO2: 25% - Na2O: 17% - K2O: 11% - V2O5: 8% - CdO: 5% - B2O3: 3% - P2O5: 2% - Li2O: 1% - Al2O3: 1%.
  • a sheet of steel, coated by dipping in accordance with the invention, in particular a layer of aluminum or a base alloy aluminum, then enamelled to obtain a shiny surface, does not have almost more surface defects.
  • the zinc coating thus obtained has good adhesion to steel substrate.
  • An IF steel strip coated under the same conditions is prepared than in test no. 3 with the difference that the coated strip is cooled to room temperature immediately after spinning and solidification of the coating layer, without passing through the rapid heating tunnel and a sheet blank C is cut from the strip obtained.
  • a sheet metal blank D is cut from the coated strip from test # 3.
  • the painted surface of the sheet blank D has a very good appearance and has almost no defects, whereas that of the blank C is very disturbed and has many micro-blisters or micro-blisters.
  • a sheet of steel, coated by dipping in accordance with the invention, in particular a layer of zinc, then painted, does not present almost more surface defects.

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  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Thermal Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Coating With Molten Metal (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Laminated Bodies (AREA)

Abstract

Interstitial free steel sheet is coated with Al, Zn or Al Zn alloy by dipping the heated steel into a relatively cool bath of molten Al, Zn or alloy and subjecting the dipped steel to a heat treatment of less than 5 mins., pref. around 2 mins., duration where it is first heated quickly to a temp. above 300 degrees C but below the temp. at which the coating would alloy with the steel and then quickly cooling to ambient temp. The heat treatment temp. is 550-625 degrees C for Al or Al alloy, 320-390 degrees C for Zn or Zn alloy and 390-550 degrees C for an alloy of Al and Zn. Prior to dipping the steel is cleaned and recrystallised by heating in a non-oxidising atmosphere. The Al based coating provides a base for subsequent enamelling and the Zn based coating for a paint coating which needs to be baked at over 100 degrees C.

Description

L'invention concerne un procédé de revêtement, au trempé et sans alliation, d'une tôle d'acier à bas interstitiel par une couche métallique à base d'aluminium ou de zinc et l'utilisation de cette tôle revêtue pour préparer ladite bande à l'émaillage ou à la mise en peinture. The invention relates to a coating method, by soaking and without alloy, of a sheet of steel with low interstitial by a metallic layer to aluminum or zinc base and the use of this coated sheet for prepare said strip for enameling or painting.

Les tôles d'acier à bas interstitiel sont généralement appelées IF (Interstitial Free) ; ces nuances d'acier contiennent des proportions suffisamment faibles d'éléments interstitiels, notamment de carbone et d'azote, ce qui permet d'éviter tout risque de sursaturation de ces éléments dans l'acier. Low interstitial steel sheets are generally called IF (Interstitial Free); these steel shades contain proportions sufficiently low interstitial elements, in particular carbon and nitrogen, which avoids any risk of supersaturation of these elements in steel.

L'emploi des tôles d'acier IF est largement répandu notamment parce que ces tôles ne présentent pas de risque de vieillissement métallurgique. The use of IF steel sheets is widespread, in particular because that these sheets do not present a risk of metallurgical aging.

Le vieillissement métallurgique est particulièrement gênant dans le cas de tôles revêtues au trempé, notamment destinées à l'émaillage ou à la mise en peinture. Metallurgical aging is particularly troublesome in the case of sheets coated by dipping, in particular intended for enamelling or for painting.

Pour le revêtement de tôles au trempé, on effectue généralement un recuit de recristallisation avant le trempé. For the coating of hot-dip sheets, generally a recrystallization annealing before quenching.

Pour le revêtement au trempé avec alliation (entre la tôle et la couche de revêtement), on effectue généralement en outre un traitement thermique d'alliation après trempé à une température suffisamment élevée pour déclencher l'alliation, ladite température étant souvent supérieure à la température de fusion du revêtement. For dip coating with alloy (between the sheet and the layer coating), a treatment is generally also carried out thermal alloy after quenching at a sufficiently high temperature to trigger the alliance, said temperature often being higher than the coating melting temperature.

Dans le cas d'acier de qualité ordinaire, c'est à dire non IF, le traitement de recuit et le traitement d'alliation contribuent à éliminer les sursaturations en carbone et en azote dans l'acier, et donc à s'affranchir des problèmes inhérents au vieillissement métallurgique. In the case of ordinary quality steel, i.e. non-IF, the annealing treatment and alloying treatment help to eliminate carbon and nitrogen oversaturations in steel, and therefore to be freed problems inherent in metallurgical aging.

Pour un revêtement au trempé mais sans alliation de ce type d'acier, le seul traitement de recuit avant le trempé ne suffit généralement pas à éliminer toutes ces sursaturations. For a dip coating but without alloying this type of steel, just annealing before tempering is usually not enough to eliminate all these supersaturations.

On procède alors, après trempé, à un traitement de vieillissement métallurgique, par exemple du type décrit dans le document DE-A-29 41 850. We then proceed, after soaking, to an aging treatment metallurgical, for example of the type described in document DE-A-29 41,850.

Mais l'invention concerne les tôles d'acier IF pour lesquelles un tel traitement de vieillissement métallurgique n'est, bien entendu, jamais envisagé après un revêtement au trempé sans alliation. However, the invention relates to IF steel sheets for which such metallurgical aging treatment is, of course, never considered after a dip coating without alloying.

L'invention concerne des revêtements à base de zinc ou d'aluminium sur ces tôles d'acier IF. The invention relates to coatings based on zinc or aluminum on these IF steel sheets.  

Il est connu d'émailler une telle tôle préalablement revêtue au trempé, notamment par une couche métallique à base d'aluminium. It is known to enamel such a sheet previously coated by dipping, in particular by a metallic layer based on aluminum.

Selon l'effet recherché, la couche d'émail déposée sur ladite tôle revêtue peut présenter un caractère mat, satiné ou brillant. Depending on the desired effect, the layer of enamel deposited on said sheet coated may have a matt, satin or shiny character.

Il est également connu de peindre une telle tôle préalablement revêtue au trempé, notamment par une couche métallique à base de zinc. It is also known to paint such a previously coated sheet by dipping, in particular by a metallic layer based on zinc.

Lors de la mise en peinture de ladite tôle revêtue, on procède généralement à une cuisson de la couche de peinture déposée dans des conditions de température prédéterminées. When painting said coated sheet, we proceed generally when the paint layer deposited in predetermined temperature conditions.

On a constaté qu'une tôle d'acier IF, revêtue au trempé et sans alliation, notamment d'aluminium ou d'un alliage à base d'aluminium, puis émaillée, notamment pour exposer une surface brillante, présentait de nombreux défauts de surface en forme de micro-piqûres ; de tels défauts sont couramment appelés "bouillons d'émail". It has been found that a sheet of IF steel, coated by tempering and without alloy, in particular of aluminum or of an alloy based on aluminum, then enamelled, in particular to expose a shiny surface, presented numerous surface defects in the form of micro-pitting; such faults are commonly called "enamel broths".

On a constaté également qu'une tôle d'acier IF, revêtue au trempé et sans alliation, notamment de zinc ou d'un alliage à base de zinc, puis peinte, présentait de nombreux défauts de surface sous-cutanés, en forme de micro-boursoufflures ou de micro-cloques. De tels défauts peuvent apparaítre ou se développer au cours du vieillissement ultérieur de la tôle. It has also been found that a sheet of IF steel, coated by dipping and without an alloy, in particular zinc or a zinc-based alloy, then painted, had many subcutaneous surface defects, shaped micro-blisters or micro-blisters. Such faults can appear or develop during the subsequent aging of the sheet.

On a constaté qu'à la surface d'une tôle d'acier IF, revêtue au trempé et sans alliation, notamment de zinc ou d'un alliage à base de zinc, apparaissait après simple vieillissement un nombre croissant de défauts en forme de micro-cloques. It was found that on the surface of a sheet of IF steel, coated by dipping and without any alloy, in particular of zinc or of a zinc-based alloy, after simple aging, an increasing number of defects appeared form of micro-blisters.

L'invention a pour but d'améliorer l'aspect de surface d'une tôle IF revêtue au trempé, notamment d'une couche métallique à base d'aluminium ou de zinc, après émaillage ou après mise en peinture ou après simple vieillissement. The invention aims to improve the surface appearance of an IF sheet coated by dipping, in particular with a metallic base layer aluminum or zinc, after enameling or after painting or after simple aging.

L'invention a pour objet un procédé de revêtement, au trempé et sans alliation, d'une tôle d'acier à bas interstitiel par une couche métallique à base d'aluminium ou de zinc selon lequel on prépare ladite tôle pour le revêtement, on trempe ladite tôle dans un bain de métal fondu, on extrait du bain ladite tôle et on solidifie la couche métallique entraínée à la surface de ladite tôle, notamment par refroidissement rapide, caractérisé en ce que, immédiatement après solidification de ladite couche métallique, on soumet ladite tôle à un traitement thermique rapide d'une durée inférieure à 5 minutes comportant une étape de chauffage rapide et une étape de refroidissement rapide à la température ambiante, ledit chauffage rapide étant adapté pour porter la surface de ladite tôle à une température supérieure à 300°C mais inférieure à la température d'alliation entre ladite tôle et ladite couche métallique. The subject of the invention is a coating process, by quenching and without alloy, of a sheet of steel with low interstitial by a metallic layer to aluminum or zinc base according to which said sheet is prepared for the coating, soaking said sheet in a bath of molten metal, extracting bath said sheet and solidifies the metallic layer entrained on the surface of said sheet, in particular by rapid cooling, characterized in that that, immediately after solidification of said metal layer, subjects said sheet to a rapid heat treatment of a shorter duration 5 minutes including a rapid heating step and a rapid cooling to room temperature, said rapid heating being adapted to bring the surface of said sheet to a temperature   higher than 300 ° C but lower than the alloying temperature between said sheet metal and said metal layer.

Pour ce type de tôle et ce type de revêtement, il est connu que ladite alliation peut se déclencher à une température inférieure à 700°C. For this type of sheet and this type of coating, it is known that said Alliation can be triggered at a temperature below 700 ° C.

L'invention peut également présenter une ou plusieurs des caractéristiques suivantes :

  • la durée dudit traitement thermique rapide est de préférence inférieure à 2 minutes environ.
  • ladite couche métallique est à base d'aluminium et ladite température de traitement thermique est comprise entre 550°C et 625°C.
  • ladite couche métallique est à base de zinc et ladite température de traitement thermique est comprise entre 320°C et 390°C.
  • ladite couche métallique est un alliage de zinc et d'aluminium et ladite température de traitement thermique est comprise entre 390°C et 550°C.
  • ledit procédé est conduit en continu.
  • pour préparer ladite tôle au revêtement, on la soumet à un traitement de recristallisation sous une atmosphère non oxydante.
The invention may also have one or more of the following characteristics:
  • the duration of said rapid heat treatment is preferably less than approximately 2 minutes.
  • said metal layer is based on aluminum and said heat treatment temperature is between 550 ° C and 625 ° C.
  • said metal layer is based on zinc and said heat treatment temperature is between 320 ° C. and 390 ° C.
  • said metal layer is an alloy of zinc and aluminum and said heat treatment temperature is between 390 ° C and 550 ° C.
  • said process is carried out continuously.
  • to prepare said sheet for coating, it is subjected to a recrystallization treatment under a non-oxidizing atmosphere.

L'invention a également pour objet l'utilisation d'une telle tôle revêtue au trempé, notamment d'une couche d'aluminium ou d'alliage d'aluminium, pour un revêtement d'émail, notamment un émail présentant une surface brillante. The invention also relates to the use of such a coated sheet by dipping, in particular with a layer of aluminum or aluminum alloy, for an enamel coating, in particular an enamel having a surface brilliant.

L'invention a également pour objet l'utilisation d'une telle tôle revêtue au trempé, notamment d'une couche de zinc, pour un revêtement de peinture, notamment une peinture nécessitant une cuisson à une température supérieure à 100°C. The invention also relates to the use of such a coated sheet by dipping, in particular with a layer of zinc, for a coating of paint, especially paint that requires cooking at a temperature above 100 ° C.

L'invention sera mieux comprise à la lecture de la description qui va suivre, donnée à titre d'exemple. The invention will be better understood on reading the description which will follow, given as an example.

L'installation de revêtement en continu au trempé d'une bande métallique comporte des moyens de préparation de la bande, des moyens de trempage de la bande dans un bain de métal fondu, des moyens de solidification et d'essorage de couche métallique et des moyens de traitement thermique rapide disposés en cascade le long d'un chemin de défilement en continu de ladite bande. The installation of continuous coating by dipping a strip metal comprises means for preparing the strip, means soaking the strip in a molten metal bath, means for solidification and dewatering of metallic layer and means of rapid heat treatment arranged in cascade along a path continuous scrolling of said strip.

Les moyens de préparation de la bande, les moyens de trempage de la bande dans un bain de métal fondu et les moyens de solidification et d'essorage de couche métallique sont connus en eux-mêmes pour le revêtement au trempé de bandes métalliques. The means for preparing the strip, the means for soaking the strip in a bath of molten metal and the solidification means and of metallic layer are known in themselves for the dip coating of metal strips.  

Les moyens de préparation de la bande comprennent notamment des moyens de préparation de la surface de la bande et des moyens de recristallisation de l'acier de la bande. The means for preparing the strip include in particular means for preparing the surface of the strip and means for recrystallization of the steel from the strip.

Les moyens de préparation de surface de la bande comprennent une enceinte de brûlage dotée de brûleurs à flamme nue orientés vers ledit chemin de défilement de bande. The means for surface preparation of the strip comprise a burning chamber with open flame burners oriented towards said tape scroll path.

Les moyens de recristallisation comprennent une enceinte thermique dont l'atmosphère est confinée et contrôlable. The recrystallization means comprise a thermal enclosure whose atmosphere is confined and controllable.

Les moyens de trempage comprennent un creuset de trempage de la bande pour contenir un bain de métal fondu. The dipping means comprise a crucible for dipping the strip to contain a bath of molten metal.

Les moyens de solidification et d'essorage comprennent des rampes de soufflage de gaz à température ambiante orientées vers le chemin de défilement de bande. The solidification and wringing means include ramps of gas blowing at room temperature oriented towards the tape scrolling.

Les moyens de traitement thermique comprennent des moyens de chauffage et des moyens de refroidissement. The heat treatment means include means for heating and cooling means.

Les moyens de chauffage se présentent sous la forme d'un tunnel équipé de rampes de rayonnement infrarouge orientées vers le chemin de défilement de bande. The heating means are in the form of a tunnel equipped with infrared radiation ramps oriented towards the path tape scrolling.

D'autres moyens de chauffage peuvent être utilisés sans se départir de la présente invention, notamment des moyens de chauffage par induction. Other heating means can be used without losing of the present invention, in particular means of heating by induction.

Les moyens de refroidissement comprennent des rampes d'éjection de gaz ou de liquide orientées vers le chemin de défilement de bande. The cooling means include ejection ramps gas or liquid oriented toward the tape running path.

On va maintenant décrire la mise en oeuvre du procédé selon l'invention à l'aide de l'installation de revêtement précédemment décrite. We will now describe the implementation of the method according to the invention using the coating installation described above.

Afin de procéder au revêtement au trempé et sans alliation d'une bande d'acier IF :

  • pour préparer ladite bande, d'une manière connue en elle-même, on fait défiler ladite bande d'acier IF dans l'enceinte de brûlage en portant sa surface à une température apte à réaliser un bon nettoyage et on la fait défiler dans l'enceinte thermique de recristallisation maintenue à une température prédéterminée, sous une atmosphère de composition prédéterminée et pendant une durée de traitement prédéterminée pour obtenir les propriétés mécaniques requises de l'acier de la bande tout en limitant l'oxydation superficielle de la bande qui peut être préjudiciable à l'adhérence de la couche métallique ; de préférence, ladite atmosphère de composition prédéterminée est non oxydante ;
  • pour revêtir ladite bande d'une couche métallique, on trempe la bande dans le creuset de trempage contenant un bain de métal fondu dont la composition a été adaptée d'une manière connue en elle-même en fonction de la nature souhaitée de la couche métallique de revêtement, on extrait la bande du creuset de trempage en entraínant à la surface de la bande une couche dudit métal fondu, on refroidit et on essore ladite couche de métal fondu à l'aide des rampes de soufflage de gaz dont le débit et la pression de gaz sont réglés d'une manière connue en elle-même pour solidifier ladite couche tout en obtenant l'épaisseur de revêtement souhaité ;
  • et on traite thermiquement et rapidement ladite bande ainsi revêtue d'une couche métallique solidifiée pendant une durée de traitement inférieure à 5 minutes en faisant défiler ladite bande successivement dans les moyens de chauffage puis dans les moyens de refroidissement pour refroidir sa surface à la température ambiante.
In order to carry out the dip coating and without alloying an IF steel strip:
  • to prepare said strip, in a manner known per se, said strip of IF steel is passed through the burning chamber by bringing its surface to a temperature capable of achieving good cleaning and it is passed through the thermal recrystallization chamber maintained at a predetermined temperature, under an atmosphere of predetermined composition and for a predetermined treatment time to obtain the required mechanical properties of the steel of the strip while limiting the surface oxidation of the strip which may be detrimental to the adhesion of the metal layer; preferably, said atmosphere of predetermined composition is non-oxidizing;
  • to coat said strip with a metallic layer, the strip is dipped in the dipping crucible containing a bath of molten metal, the composition of which has been adapted in a manner known per se depending on the desired nature of the metallic layer coating, we extract the strip from the dipping crucible by causing on the surface of the strip a layer of said molten metal, cool and wring said layer of molten metal using gas blowing ramps whose flow and gas pressure are adjusted in a manner known per se to solidify said layer while obtaining the desired coating thickness;
  • and said strip thus coated with a solidified metal layer is thermally and rapidly treated for a treatment period of less than 5 minutes by passing said strip successively through the heating means and then through the cooling means in order to cool its surface to ambient temperature .

De préférence, la durée du traitement thermique rapide est inférieure à 2 minutes. Preferably, the duration of the rapid heat treatment is less than 2 minutes.

La puissance de rayonnement des rampes à infrarouge du tunnel de chauffage et la longueur dudit tunnel sont adaptées d'une manière connue en elle-même pour que la température de la surface de la bande soit portée à une température supérieure à 300°C mais inférieure à la température d'alliation entre ladite tôle et ladite couche métallique. The radiation power of the infrared ramps of the tunnel heating and the length of said tunnel are adapted in a known manner in itself so that the temperature of the surface of the strip is brought up at a temperature above 300 ° C but below the temperature of alloy between said sheet and said metal layer.

Lorsque l'on procède à un revêtement d'aluminium ou d'alliage d'aluminium, ladite température de surface de la bande est de préférence comprise entre 550°C et 625°C. When coating aluminum or alloy aluminum, said strip surface temperature is preferably between 550 ° C and 625 ° C.

Lorsque l'on procède à un revêtement de zinc ou d'alliage de zinc, ladite température de surface de la bande est de préférence comprise entre 320°C et 390°C. When coating with zinc or zinc alloy, said surface temperature of the strip is preferably between 320 ° C and 390 ° C.

Lorsque l'on procède à un revêtement d'alliage de zinc et d'aluminium, ladite température de surface de la bande est de préférence comprise entre 390°C et 550°C. When coating with zinc alloy and aluminum, said strip surface temperature is preferably between 390 ° C and 550 ° C.

Le débit de gaz des rampes d'éjection des moyens de refroidissement et le nombre de rampes le long du chemin de défilement de bande sont adaptés d'une manière connue en elle-même pour refroidir la surface de la bande à la température ambiante. The gas flow rate of the ejection ramps of the cooling means and the number of ramps along the tape running path are adapted in a manner known per se to cool the surface of the tape at room temperature.

La demanderesse a constaté avec surprise qu'une tôle d'acier IF, ainsi revêtue au trempé et sans alliation, notamment d'aluminium ou d'un alliage à base d'aluminium, puis émaillée pour obtenir une surface brillante, ne présentait plus de défauts de surface. The Applicant has found with surprise that a sheet of IF steel, as well coated by dipping and without alloy, in particular aluminum or an alloy   based on aluminum, then enamelled to obtain a shiny surface, do not had more surface defects.

De la même manière, la demanderesse a constaté qu'une tôle d'acier, ainsi revêtue au trempé et sans alliation, notamment de zinc ou d'un alliage à base de zinc, puis peinte, ne présentait pas non plus de défauts de surface. Similarly, the Applicant has found that a sheet of steel, thus coated by dipping and without alloying, in particular zinc or a zinc-based alloy, then painted, also had no defects of surface.

La demanderesse a également constaté que des défauts de surface n'apparaissent plus après vieillissement d'une tôle d'acier IF, ainsi revêtue au trempé, notamment de zinc ou d'un alliage à base de zinc. The Applicant has also found that surface defects no longer appear after aging of an IF steel sheet, thus coated by dipping, in particular zinc or a zinc-based alloy.

Les essais suivants illustrent l'invention :The following tests illustrate the invention: Essai n°1 : Test # 1 :

Cet essai a pour but d'illustrer le procédé selon l'invention de revêtement au trempé d'une bande d'acier IF par une couche d'alliage d'aluminium. The purpose of this test is to illustrate the method according to the invention of dip coating of an IF steel strip with a layer of alloy aluminum.

L'alliage d'aluminium à déposer contient, en poids, 90% d'aluminium et 10% de silicium et fond à une température d'environ 680°C. The aluminum alloy to be deposited contains, by weight, 90% aluminum and 10% silicon and melts at a temperature of about 680 ° C.

La longueur du tunnel des moyens de chauffage pour le traitement thermique selon l'invention est de 80 m environ. The length of the tunnel of heating means for treatment thermal according to the invention is about 80 m.

On fait défiler la bande d'acier à revêtir au trempé à une vitesse de 80 m/minute dans l'installation précédemment décrite selon les conditions particulières suivantes :

  • on prépare la bande selon les étapes suivantes :
    • nettoyage de la surface par brûlage en portant la surface de la bande à 600°C ;
    • traitement de recristallisation pendant 2 à 5 minutes sous une atmosphère composée d'azote à 80% et d'hydrogène à 20% pour porter la bande à une température comprise entre 750°C et 850°C ;
  • on refroidit la bande à une température de environ 680°C, on trempe la bande dans un bain de l'alliage d'aluminium en fusion, on extrait la bande dudit bain, on essore la bande tout en solidifiant la couche d'alliage entraínée sur la bande ;
  • en sortie d'essorage, quand la couche métallique est solidifiée, on fait ensuite défiler la bande pendant environ 1 minute dans le tunnel de traitement thermique pour porter sa surface à une température d'environ 600 °C au bout de 30 secondes et l'y maintenir à cette température pendant environ 30 secondes et, en sortie dudit tunnel, on fait défiler la bande pendant environ 15 secondes dans le champ d'éjecteurs de gaz de refroidissement pour refroidir sa surface à la température ambiante.
The steel strip to be coated is passed through at a speed of 80 m / minute in the installation previously described under the following specific conditions:
  • the strip is prepared according to the following steps:
    • cleaning of the surface by burning by bringing the surface of the strip to 600 ° C;
    • recrystallization treatment for 2 to 5 minutes under an atmosphere composed of 80% nitrogen and 20% hydrogen to bring the strip to a temperature between 750 ° C and 850 ° C;
  • the strip is cooled to a temperature of approximately 680 ° C., the strip is dipped in a bath of molten aluminum alloy, the strip is extracted from said bath, the strip is wrung out while solidifying the entrained layer of alloy on the tape;
  • at the exit of spinning, when the metal layer is solidified, the strip is then made to run for approximately 1 minute in the heat treatment tunnel to bring its surface to a temperature of approximately 600 ° C. after 30 seconds and the maintain it at this temperature for approximately 30 seconds and, at the exit from said tunnel, the strip is made to run for approximately 15 seconds in the field of cooling gas ejectors to cool its surface to ambient temperature.

Le revêtement d'alliage d'aluminium ainsi obtenu présente une bonne adhérence au substrat d'acier et un aspect de surface homogène. The aluminum alloy coating thus obtained has good adhesion to the steel substrate and a homogeneous surface appearance.

Essai n°2 : Test # 2 :

Cet essai a pour but d'illustrer l'amélioration de l'état de surface d'une tôle revêtue selon l'invention puis émaillée pour obtenir une surface brillante. The purpose of this test is to illustrate the improvement of the surface condition of a coated sheet according to the invention then enamelled to obtain a surface brilliant.

On prépare une bande d'acier IF revêtue dans les mêmes conditions que dans l'essai n°1 à la différence près qu'on refroidit la bande revêtue à la température ambiante immédiatement après essorage et solidification de la couche de revêtement, sans passer par le tunnel de chauffage rapide et on découpe dans la bande obtenue un flan de tôle A. An IF steel strip coated under the same conditions is prepared than in test no. 1, with the difference that the coated strip is cooled to room temperature immediately after spinning and solidification of the coating layer, without passing through the rapid heating tunnel and a sheet blank A is cut from the strip obtained.

On découpe un flan de tôle B dans la bande revêtue issue de l'essai n°1. A sheet blank B is cut from the coated strip from test # 1.

On met en forme les flans de tôle A et B, on dégraisse leur surface, on les recouvre d'une couche crue d'émail, dont la composition est connue en elle-même pour donner un émail de surface brillante, et on procède ensuite à leur cuisson à une température de environ 560°C pendant 10 minutes. We shape the sheet blanks A and B, we degrease their surface, they are covered with a raw layer of enamel, the composition of which is known in itself to give a shiny surface enamel, and we proceed then to their cooking at a temperature of about 560 ° C for 10 minutes.

L'émail utilisé peut présenter la composition suivante : Si02 : 27% - TiO2 : 25% - Na2O : 17% - K2O : 11% - V2O5 : 8% - CdO : 5% - B2O3 : 3% - P2O5 : 2% - Li2O : 1% - Al2O3 : 1%. The enamel used can have the following composition: Si02: 27% - TiO2: 25% - Na2O: 17% - K2O: 11% - V2O5: 8% - CdO: 5% - B2O3: 3% - P2O5: 2% - Li2O: 1% - Al2O3: 1%.

On constate que la surface émaillée et brillante du flan de tôle B a un très bon aspect et ne présente quasiment pas de défauts, alors que celle du flan A est très perturbée et présente de nombreuses micro-piqûres ou "bouillons d'émail". It can be seen that the enameled and shiny surface of the sheet blank B has a very good appearance and has almost no defects, whereas that blank A is very disturbed and has numerous micro-bites or "enamel broths".

Par des moyens optiques, on évalue par comptage la densité de défauts de surface : flan A : 200 défauts pour 100 cm2 - flan B : 2 défauts pour 100 cm2. By optical means, the density of surface defects: blank A: 200 defects per 100 cm2 - blank B: 2 defects for 100 cm2.

Ainsi, une tôle d'acier, revêtue au trempé en procédant selon l'invention, notamment d'une couche d'aluminium ou d'un alliage à base d'aluminium, puis émaillée pour obtenir une surface brillante, ne présente quasiment plus de défauts de surface. Thus, a sheet of steel, coated by dipping in accordance with the invention, in particular a layer of aluminum or a base alloy aluminum, then enamelled to obtain a shiny surface, does not have almost more surface defects.

Essai n°3 : Test # 3 :

On prépare une bande d'acier IF revêtue au trempé d'une couche de zinc d'une épaisseur de 30 micromètres dans les mêmes conditions que dans l'essai n°1 aux différences suivantes près ;

  • le creuset de trempage de la bande contient du zinc fondu à une température de environ 450°C.
  • dans le tunnel de traitement thermique rapide, la température à laquelle on porte puis on maintient la surface de la bande est d'environ 360°C.
A strip of IF steel is prepared by dipping a layer of zinc with a thickness of 30 micrometers under the same conditions as in test No. 1 with the following differences;
  • the strip dipping crucible contains molten zinc at a temperature of approximately 450 ° C.
  • in the rapid heat treatment tunnel, the temperature at which the surface is brought to and then maintained is approximately 360 ° C.

Le revêtement de zinc ainsi obtenu présente une bonne adhérence au substrat d'acier. The zinc coating thus obtained has good adhesion to steel substrate.

Même après vieillissement de la bande d'acier ainsi galvanisée, on n'observe pas de défauts à la surface du revêtement de zinc. Even after the steel strip thus galvanized has aged, does not observe any defects on the surface of the zinc coating.

Essai n°4 : Test # 4 :

Cet essai a pour but d'illustrer l'amélioration de l'état de surface d'une tôle revêtue selon l'invention puis peinte. The purpose of this test is to illustrate the improvement of the surface condition of a coated sheet according to the invention then painted.

On prépare une bande d'acier IF revêtue dans les mêmes conditions que dans l'essai n°3 à la différence près qu'on refroidit la bande revêtue à la température ambiante immédiatement après essorage et solidification de la couche de revêtement, sans passer par le tunnel de chauffage rapide et on découpe dans la bande obtenue un flan de tôle C. An IF steel strip coated under the same conditions is prepared than in test no. 3 with the difference that the coated strip is cooled to room temperature immediately after spinning and solidification of the coating layer, without passing through the rapid heating tunnel and a sheet blank C is cut from the strip obtained.

On découpe un flan de tôle D dans la bande revêtue issue de l'essai n°3. A sheet metal blank D is cut from the coated strip from test # 3.

Pour préparer la peinture des flans de tôle C et D, on les dégraisse dans une solution alcaline à 55°C pendant 4 minutes, on les trempe dans une solution d'affinage à température ambiante pendant 1 minute, puis dans une solution de phosphatation tricationique à 55°C pendant 2 minutes, puis dans une solution de passivation chromique à température ambiante pendant 1 minute et on sèche les flans de tôle ainsi préparés. To prepare the painting of sheet metal blanks C and D, they are degreased in an alkaline solution at 55 ° C for 4 minutes, they are soaked in a ripening solution at room temperature for 1 minute, then in a tricationic phosphating solution at 55 ° C for 2 minutes, then in a chromic passivation solution at temperature ambient for 1 minute and the sheet blanks thus prepared are dried.

Pour peindre de la même façon les flans de tôle C et D ainsi préparés, on dépose d'une manière connue trois couches successives de peinture, la première couche étant déposée par cataphorèse et les deux autres au pistolet et on procède à une cuisson après le dépôt de chaque couche à une température comprise entre 150°C et 170°C et pendant une durée comprise entre 20 et 25 minutes. To paint the sheet blanks C and D in this way in the same way, three successive layers of paint are deposited in a known manner, the first layer being deposited by cataphoresis and the other two at spray gun and bake after each layer has been deposited a temperature between 150 ° C and 170 ° C and for a period between 20 and 25 minutes.

On constate que la surface peinte du flan de tôle D a un très bon aspect et ne présente quasiment pas de défauts, alors que celle du flan C est très perturbée et présente de nombreuses micro-boursouflures ou micro-cloques. It can be seen that the painted surface of the sheet blank D has a very good appearance and has almost no defects, whereas that of the blank C is very disturbed and has many micro-blisters or micro-blisters.

Par des moyens optiques, on évalue par comptage la densité de défauts de surface : flan C : 200 défauts pour 100 cm2 - flan D : 2 défauts pour 100 cm2. By optical means, the density of surface defects: blank C: 200 defects per 100 cm2 - blank D: 2 defects for 100 cm2.  

Ainsi, une tôle d'acier, revêtue au trempé en procédant selon l'invention, notamment d'une couche de zinc , puis peinte, ne présente quasiment plus de défauts de surface. Thus, a sheet of steel, coated by dipping in accordance with the invention, in particular a layer of zinc, then painted, does not present almost more surface defects.

Claims (9)

Procédé de revêtement, au trempé et sans alliation, d'une tôle d'acier à bas interstitiel par une couche métallique à base d'aluminium ou de zinc selon lequel on prépare ladite tôle pour le revêtement, on trempe ladite tôle dans un bain de métal fondu, on extrait du bain ladite tôle et on solidifie la couche métallique entraínée à la surface de ladite tôle, notamment par refroidissement rapide, caractérisé en ce que, immédiatement après solidification de ladite couche métallique, on soumet ladite tôle à un traitement thermique rapide d'une durée inférieure à 5 minutes comportant une étape de chauffage rapide et une étape de refroidissement rapide à la température ambiante, ledit chauffage rapide étant adapté pour porter la surface de ladite tôle à une température supérieure à 300°C mais inférieure à la température d'alliation entre ladite tôle et ladite couche métallique . Coating process, by dipping and without alloying, of a sheet low interstitial steel by a metallic layer based on aluminum or of zinc according to which said sheet is prepared for coating, it is quenched said sheet in a molten metal bath, said sheet is extracted from the bath and solidifies the metallic layer entrained on the surface of said sheet, in particular by rapid cooling, characterized in that, immediately after solidification of said metal layer, it is subjected said sheet to rapid heat treatment lasting less than 5 minutes comprising a rapid heating stage and a rapid cooling to room temperature, said rapid heating being adapted to bring the surface of said sheet to a temperature higher than 300 ° C but lower than the alloying temperature between said sheet metal and said metal layer. Procédé de revêtement au trempé selon la revendication 1 caractérisé en ce que la durée dudit traitement thermique rapide est de préférence inférieure à 2 minutes environ. A dip coating method according to claim 1 characterized in that the duration of said rapid heat treatment is preferably less than about 2 minutes. Procédé de revêtement au trempé selon la revendication 1 ou 2 caractérisé en ce que ladite couche métallique est à base d'aluminium et en ce que ladite température de traitement thermique est comprise entre 550°C et 625°C. Dip coating method according to claim 1 or 2 characterized in that said metallic layer is based on aluminum and in that said heat treatment temperature is between 550 ° C and 625 ° C. Procédé de revêtement au trempé selon la revendication 1 ou 2 caractérisé en ce que ladite couche métallique est à base de zinc et en ce que ladite température de traitement thermique est comprise entre 320°C et 390°C. Dip coating method according to claim 1 or 2 characterized in that said metallic layer is based on zinc and in that that said heat treatment temperature is between 320 ° C. and 390 ° C. Procédé de revêtement au trempé selon la revendication 1 ou 2 caractérisé en ce que ladite couche métallique est un alliage de zinc et d'aluminium et en ce que ladite température de traitement thermique est comprise entre 390°C et 550°C. Dip coating method according to claim 1 or 2 characterized in that said metallic layer is a zinc alloy and aluminum and in that said heat treatment temperature is between 390 ° C and 550 ° C. Procédé de revêtement au trempé selon l'une quelconque des revendications précédentes caractérisé en ce qu'il est conduit en continu. A dip coating method according to any one of previous claims characterized in that it is continuously driven.   Procédé de revêtement au trempé d'une tôle d'acier selon l'une quelconque des revendications précédentes caractérisé en ce que, pour préparer ladite tôle au revêtement, on la soumet à un traitement de recristallisation sous une atmosphère non oxydante. Method for the dip coating of a steel sheet according to one any one of the preceding claims, characterized in that, for prepare said sheet for coating, it is subjected to a treatment of recrystallization under a non-oxidizing atmosphere. Utilisation d'une tôle revêtue au trempé selon l'une quelconque des revendications 1, 2, 3, 6 et 7, notamment revêtue d'une couche d'aluminium ou d'alliage d'aluminium, pour un revêtement d'émail, notamment un émail présentant une surface brillante. Use of a dip-coated sheet according to any one of claims 1, 2, 3, 6 and 7, in particular coated with a layer of aluminum or aluminum alloy, for an enamel coating, especially an enamel with a shiny surface. Utilisation d'une tôle revêtue au trempé selon l'une quelconque des revendications 1, 2, 4 à 7, notamment d'une couche de zinc ou d'alliage de zinc, pour un revêtement de peinture, notamment une peinture nécessitant une cuisson à une température supérieure à 100°C. Use of a dip-coated sheet according to any one of claims 1, 2, 4 to 7, in particular a layer of zinc or zinc alloy, for a coating of paint, in particular a paint requiring cooking at a temperature above 100 ° C.
EP95402327A 1994-11-04 1995-10-19 Method for hot-dip coating without alloying a low interstitial steel plate Expired - Lifetime EP0710732B1 (en)

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FR9413165A FR2726578B1 (en) 1994-11-04 1994-11-04 PROCESS FOR THE TEMPER COATING OF A STEEL SHEET WITH A METAL LAYER BASED ON ALUMINUM OR ZINC
FR9413165 1994-11-04

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998021378A1 (en) * 1996-11-09 1998-05-22 Thyssen Stahl Ag METHOD OF HEAT-TREATING THIN SHEET COATED WITH ZnAl BY HOT DIP GALVANIZATION
EP0916624A1 (en) * 1997-11-11 1999-05-19 Kawasaki Steel Corporation Porcelain-enameled steel sheets and frits for enameling
FR2775297A1 (en) * 1998-02-25 1999-08-27 Lorraine Laminage PIPE WITH CRACK RESISTANT ALUMINUM COATING
WO2008138729A1 (en) * 2007-05-10 2008-11-20 Thyssenkrupp Steel Ag Multi-layer composite part made of steel having optimized paint adhesion
US8475609B2 (en) 2006-05-24 2013-07-02 Bluescope Steel Limited Treating Al/Zn-based alloy coated products
US10731241B2 (en) 2009-05-28 2020-08-04 Bluescope Steel Limited Metal-coated steel strip

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3297499A (en) * 1964-04-02 1967-01-10 Nat Steel Corp Method for heat treating steel strip
DE2941850A1 (en) 1978-10-16 1980-04-30 Nisshin Steel Co Ltd Overageing hot dip coated steel - to improve formability, is carried out continuously and involves heating up and cooling at specified rates

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6048570B2 (en) * 1978-12-25 1985-10-28 日新製鋼株式会社 Continuous over-aging treatment method for continuous molten aluminized steel sheets
BE874599A (en) * 1979-03-02 1979-09-03 Centre Rech Metallurgique METHOD FOR MANUFACTURING A COATED STEEL STRIP
JPS61223174A (en) * 1985-03-28 1986-10-03 Sumitomo Metal Ind Ltd Production of zinc alloyed and hot dipped steel sheet
JPS62130268A (en) * 1985-12-02 1987-06-12 Kawasaki Steel Corp Production of hot dip zinc coated mild steel sheet for working subjected to alloying treatment
BE1005288A6 (en) * 1990-09-27 1993-06-22 Centre Rech Metallurgique Installation for the continuous treatment of a galvanised steel strip andprocess for using same
JPH05247619A (en) * 1992-03-03 1993-09-24 Nippon Steel Corp Vertical type galvannealing furnace for manufacturing galvannealed steel sheet

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3297499A (en) * 1964-04-02 1967-01-10 Nat Steel Corp Method for heat treating steel strip
DE2941850A1 (en) 1978-10-16 1980-04-30 Nisshin Steel Co Ltd Overageing hot dip coated steel - to improve formability, is carried out continuously and involves heating up and cooling at specified rates

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
C.E. JORDAN: "interfacial layer development in hot-dip galvanneal coatings on interstitial free steel", METALLURGICAL AND MATERIALS TRANSACTIONS A PHYSICAL METALLURGY AND MATERIALS SCIENCE, vol. 25a, no. 10, WARRENDALE,PA,US, pages 2101 - 2109, XP000445070 *
C.E.JORDAN: "morphology development in hot-dip galvanneal coatings", METALLURGICAL AND MATERIALS TRANSACTIONS A PHYSICAL METALLURGY AND MATERIALS SCIENCE, vol. 25a, no. 5, WARRENDALE,PA,US, pages 937 - 947, XP000442625 *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU728356B2 (en) * 1996-11-09 2001-01-04 Thyssen Stahl Aktiengesellschaft Method of heat-treating thin sheet coated with ZnAl by hot dip galvanization
US6231695B1 (en) 1996-11-09 2001-05-15 Thyssen Stahl Ag Method of heat-treating a thin sheet coated with ZnAL by hot dip galvanization
WO1998021378A1 (en) * 1996-11-09 1998-05-22 Thyssen Stahl Ag METHOD OF HEAT-TREATING THIN SHEET COATED WITH ZnAl BY HOT DIP GALVANIZATION
EP0916624A1 (en) * 1997-11-11 1999-05-19 Kawasaki Steel Corporation Porcelain-enameled steel sheets and frits for enameling
US5993974A (en) * 1997-11-11 1999-11-30 Kawasaki Steel Corporation Porcelain-enameled steel sheets and frits for enameling
EP0939141A1 (en) * 1998-02-25 1999-09-01 Sollac Steel plate with aluminum coating having stress cracking resistance
FR2775297A1 (en) * 1998-02-25 1999-08-27 Lorraine Laminage PIPE WITH CRACK RESISTANT ALUMINUM COATING
US6328824B1 (en) 1998-02-25 2001-12-11 Sollac Sheet with aluminum coating that is resistant to cracking
US6395407B2 (en) 1998-02-25 2002-05-28 Sollac Sheet with aluminum coating that is resistant to cracking
US8475609B2 (en) 2006-05-24 2013-07-02 Bluescope Steel Limited Treating Al/Zn-based alloy coated products
WO2008138729A1 (en) * 2007-05-10 2008-11-20 Thyssenkrupp Steel Ag Multi-layer composite part made of steel having optimized paint adhesion
CN101952114A (en) * 2007-05-10 2011-01-19 蒂森克虏伯钢铁欧洲股份公司 Multi-layer composite part made of steel having optimized paint adhesion
US8221898B2 (en) 2007-05-10 2012-07-17 Thyssenkrupp Steel Europe Ag Multi-layered composite part made of steel having optimized paint adhesion
CN101952114B (en) * 2007-05-10 2013-10-30 蒂森克虏伯钢铁欧洲股份公司 Multi-layer composite part made of steel having optimized paint adhesion
US10731241B2 (en) 2009-05-28 2020-08-04 Bluescope Steel Limited Metal-coated steel strip

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ES2111380T3 (en) 1998-03-01
EP0710732B1 (en) 1998-01-07
FR2726578B1 (en) 1996-11-29
FR2726578A1 (en) 1996-05-10
ATE161898T1 (en) 1998-01-15
DE69501386T2 (en) 1998-07-23

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