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EP0959145B1 - Procédé et installation pour effectuer le chauffage d'un procédé de recuit après galvanisation - Google Patents

Procédé et installation pour effectuer le chauffage d'un procédé de recuit après galvanisation Download PDF

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Publication number
EP0959145B1
EP0959145B1 EP99109130A EP99109130A EP0959145B1 EP 0959145 B1 EP0959145 B1 EP 0959145B1 EP 99109130 A EP99109130 A EP 99109130A EP 99109130 A EP99109130 A EP 99109130A EP 0959145 B1 EP0959145 B1 EP 0959145B1
Authority
EP
European Patent Office
Prior art keywords
heating
zone
annealing
maintaining
strip
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
EP99109130A
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German (de)
English (en)
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EP0959145A1 (fr
Inventor
Rolf Brisberger
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.)
SMS Siemag AG
Original Assignee
SMS Demag AG
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Filing date
Publication date
Application filed by SMS Demag AG filed Critical SMS Demag AG
Publication of EP0959145A1 publication Critical patent/EP0959145A1/fr
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Anticipated expiration legal-status Critical
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    • 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

Definitions

  • the invention relates to a method and an apparatus for Execution of the annealing of a galvannealing process, at the strips and sheets, especially of steel, after a Hot galvanizing are subjected to annealing Heating the coated material with the following Keep at glowing end temperature.
  • the coating of the coated tape treated in this way exists only from iron-zinc compounds with approx. 10-12% Fe.
  • the annealing of a galvannealing process goes a conventional one Hot-dip galvanizing process ahead.
  • the Steel surface cleaned first.
  • one recrystallizing annealing of the hard-rolled input material performed in an oven under a protective gas atmosphere.
  • the strip is then cooled to the galvanizing temperature and hot-dip galvanized using an aluminum-containing zinc melt. Finally, the excess zinc melt stripped with air or nitrogen.
  • Such a galvannealing process is known from JP-08-165550 A. This describes a hot dip galvanizing process with two warming up steps during the Subsequent annealing treatment to a zinc galvanized sheet to improve that the plating layers when the Do not lift off the sheet (so-called "flaking").
  • phase structure set for this annealing is for Quality of the coating as well as the usability of the galvannealing-treated Base material crucial, for example during the later deep-drawing process in the press shop.
  • This galvannealing furnace is used in conventional systems consisting of two zones: on the one hand, the zone for inductive heating of the tape and on the other hand the adjoining zone to keep at the desired final temperature.
  • the stop zone is usually via resistance-heated or gas-fired Heated parts.
  • the phase structure of the coating material is special depending on the parameters temperature and time. These important Parameters can be determined by the system parameters, the strip infeed temperature in the zinc smelt, the temperature of the Zinc melt, the aluminum concentration in the zinc melt and the thickness of the coating can be influenced. The most essential The influencing variable is the base material, i.e. the alloy composition of the steel and its condition.
  • Galvannealing-treated sheet is mainly found in the Automotive industry use and is characterized by good Weldability and paintability.
  • IF steels are steels that are not interstitial in the iron grid have dissolved atoms.
  • the C and N atoms are through selectively added carbonitride formers (Ti, Nb, V).
  • IF steels have no noteworthy levels strength-increasing elements such as P, Mn or B.
  • the Element Si can improve the adhesion of the Galvanealed coating can be added (up to approx. 0.10%).
  • the two steel groups, IF steels and higher strength steels, have, however, in relation to the applied zinc coating a clearly different alloy behavior, especially with regard to their speed. in this connection Alloy formation in the high-strength steels runs significantly slower than with the IF steels.
  • the present invention is therefore based on the object a method and an apparatus for the annealing of a galvannealing process to propose the sheets and strips different base materials, in particular high-strength steels without being subjected to performance losses can
  • the core of the invention is the adaptation of the glow cycle with regard to the parameters of temperature and time for the base materials, here in particular high-strength steels, to be taken into account the material-specific progress of the alloy.
  • the proposed process engineering in the form of a gradual Annealing treatment is an opportunity for controlled adjustment the properties between base material and coating material as well as the covering material itself.
  • This annealing treatment should advantageously be carried out in this way be that the heating process with subsequent hold on Final temperature by a second holding process at one temperature interrupted below the final temperature.
  • this be a zone for inductive Heating the belt and another zone for Maintaining the tape at the warm-up temperature includes between the zone for inductive heating of the strip and the End stop zone at least one further stop zone is provided is.
  • the proposed procedure of the gradual Annealing treatment in a galvannealing process as well as the proposed one The structure of the annealing furnace shows the following advantages:
  • the annealing parameters are the alloy sequence of the combination Steel / coating material adapted. This is not the point overheating in the coating material without a Alloy formation occurs. Furthermore, one becomes possible counteracted increased evaporation of zinc. This is a major advantage for both the operation of the Galvannealed furnace as well as for the morphology of the Galvannealed coating.
  • the method according to the invention means and the proposed furnace no loss in performance of the hot-dip galvanizing plant.
  • FIG 1 shows schematically the structure of the invention Galvannealing furnace variant with interrupted heating zone.
  • the galvanealing furnace 1 comprises a first zone 2a for inductive heating. This is followed by a holding zone 3a on. After this holding zone 3a, the belt is passed through again led a heating zone 2b. Then in one second holding zone 3b the coated strip to the final temperature held.
  • Figure 3 shows an example of such Step-by-step heating curve resulting from furnace build-up (Curve course c).
  • the line speed is here 90m / min.
  • the belt runs at an initial temperature of 420 ° C in the oven and will quickly open in a first stage Heated to 470 ° C.
  • the belt then runs into the first holding zone (3a) and is kept at the intermediate temperature for about 7s. Then another heating process takes place on the Final glowing temperature of 520 ° C instead.
  • FIGS. 2a and b schematically show the structure of conventional ones Galvannealing ovens shown. Both variants exist from a first zone for inductive heating 2 as well a second, adjoining zone 3, for holding the Band to final temperature.
  • Known systems with inductive Band heating have either in the inductive heating section 2 several induction coils 2a, b, c, d, usually 4-7 coils, on ( Figure 2a) or include only a single induction coil 2 ( Figure 2b).
  • This single coil 2 has the same installed capacity as the previous several Coils together. The difference is in the essential smaller band area in the inductor, which makes the specific Performance or power density is significantly increased, what manifests itself in a higher heating rate.
  • FIG. 3 The temperature-time profiles of the annealing treatments after Oven variants of FIGS. 2a and b are also shown in FIG. 3 shown.
  • the furnace according to the invention quickly reached the final glowing temperature. This is convenient for IF steels, the alloying point of which is already shorter Time is reached.
  • the alloying point also becomes due to higher alloy contents in the steel only after prolonged glow reached.
  • To overheat the coating to avoid and a controlled alloy process between base material and coating material as well as in Setting the coating material yourself will be a Intermediate annealing introduced with subsequent heating up Glowing temperature. Furthermore, one is hereby possible Evaporation of zinc counteracted in the galvannealing furnace.

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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)
  • Laser Beam Processing (AREA)
  • Magnetic Heads (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Tunnel Furnaces (AREA)

Claims (6)

  1. Procédé pour réaliser le recuit d'un procédé de galvanisation dans lequel des bandes et des tôles en acier sont soumises, après une galvanisation à chaud, à un recuit par chauffage graduel du matériau revêtu avec un maintien consécutif à la température finale du recuit, caractérisé en ce que pour le traitement d'aciers présentant différentes compositions d'alliage, qui présentent un comportement d'alliage différent par rapport au revêtement de zinc appliqué, l'étape de chauffage est interrompue pendant le recuit pendant au moins une autre étape de maintien, la bande ou la tôle en acier galvanisée à chaud étant chauffée rapidement dans une première étape de chauffage, puis introduite dans une première zone de maintien pour la réalisation d'une étape de maintien, présentant une durée plus longue par rapport à l'étape de chauffage, est soumise à une deuxième étape de chauffage rapide, le chauffage pendant l'étape de chauffage étant réalisé par induction et le chauffage pendant chaque étape de maintien étant réalisé au moyen d'un chauffage à résistances ou au gaz.
  2. Procédé selon la revendication 1, caractérisé en ce que le processus de chauffage avec un maintien consécutif à la température finale est interrompu par une étape de maintien à une température inférieure à la température finale.
  3. Dispositif pour réaliser le recuit d'un procédé de galvanisation selon la revendication 1, dans lequel des bandes et des tôles en acier sont soumises, après une galvanisation à chaud, à un recuit par chauffage graduel du matériau revêtu avec un maintien consécutif à la température finale du recuit, comprenant une zone pour le chauffage par induction de la bande ou de la tôle en acier ainsi qu'une autre zone pour le maintien de la bande ou de la tôle à la température finale, caractérisé en ce que la zone pour le chauffage par induction de la bande (2a, 2b) est interrompue par au moins une autre zone de maintien (3a), comprenant une première zone de chauffage (2a) pour le chauffage rapide de la bande ou de la tôle galvanisée en acier, une zone de maintien consécutive pour réaliser une étape de maintien, présentant une durée plus longue par rapport à l'étape de chauffage, et une deuxième zone de chauffage (2b) pour le chauffage rapide de la bande ou de la tôle, les zones de chauffage (2a, 2b) étant chauffées par induction et chaque zone de maintien (3a) étant chauffée par résistance ou au gaz.
  4. Dispositif selon la revendication 3, caractérisé en ce qu'on a prévu une première zone par induction (2a) avec une première zone de maintien (3a) consécutive ainsi qu'une deuxième zone par induction (2b) consécutive avec une deuxième zone de maintien (3b) consécutive.
  5. Dispositif selon la revendication 4, caractérisé en ce que les zones pour le chauffage par induction (2a, 2b) sont constituées de plusieurs bobines d'induction.
  6. Dispositif selon la revendication 4, caractérisé en ce que les zones pour le chauffage par induction (2a, 2b) sont constituées d'une bobine d'induction.
EP99109130A 1998-05-16 1999-05-08 Procédé et installation pour effectuer le chauffage d'un procédé de recuit après galvanisation Expired - Lifetime EP0959145B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19822156 1998-05-16
DE19822156A DE19822156A1 (de) 1998-05-16 1998-05-16 Verfahren und Vorrichtung zur Durchführung der Glühung eines Galvannealing-Prozesses

Publications (2)

Publication Number Publication Date
EP0959145A1 EP0959145A1 (fr) 1999-11-24
EP0959145B1 true EP0959145B1 (fr) 2003-01-15

Family

ID=7868091

Family Applications (1)

Application Number Title Priority Date Filing Date
EP99109130A Expired - Lifetime EP0959145B1 (fr) 1998-05-16 1999-05-08 Procédé et installation pour effectuer le chauffage d'un procédé de recuit après galvanisation

Country Status (7)

Country Link
US (1) US6379481B2 (fr)
EP (1) EP0959145B1 (fr)
JP (1) JP2000026948A (fr)
AT (1) ATE231191T1 (fr)
CA (1) CA2271816A1 (fr)
DE (2) DE19822156A1 (fr)
ES (1) ES2192356T3 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10023312C1 (de) * 2000-05-15 2001-08-23 Thyssenkrupp Stahl Ag Galvannealed-Feinblech und Verfahren zum Herstellen von derartigem Feinblech

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3058840A (en) * 1959-04-16 1962-10-16 Electric Furnace Co Induction strip heating apparatus
US3307968A (en) * 1963-09-03 1967-03-07 Armco Steel Corp Method and apparatus for controlling the alloying of zinc coatings
US3398252A (en) * 1965-11-15 1968-08-20 Westinghouse Electric Corp Heat treatment apparatus
JPS5263123A (en) * 1975-11-19 1977-05-25 Toyo Kogyo Co Production method of reactor material having excellent deformation resistance
US4287008A (en) * 1979-11-08 1981-09-01 Bethlehem Steel Corporation Method of improving the ductility of the coating of an aluminum-zinc alloy coated ferrous product
JPS5834167A (ja) * 1981-08-25 1983-02-28 Nippon Kokan Kk <Nkk> 溶融亜鉛メツキ鋼板のＦｅ−Ｚｎ合金化処理方法
JPS5834168A (ja) * 1981-08-25 1983-02-28 Nippon Kokan Kk <Nkk> 溶融亜鉛メツキ鋼板のＦｅ−Ｚｎ合金化処理方法
FR2546534B1 (fr) * 1983-05-24 1989-04-21 Usinor Procede et installation de fabrication en continu d'une bande d'acier survieillie portant un revetement de zn, al ou d'alliage zn-al
JP2658580B2 (ja) * 1990-12-29 1997-09-30 日本鋼管株式会社 プレス成形性および耐パウダリング性の優れた合金化溶融亜鉛めっき鋼板の製造方法
JP2707952B2 (ja) * 1993-07-19 1998-02-04 住友金属工業株式会社 界面密着性に優れた合金化溶融Ｚｎめっき鋼板およびその製造方法
BE1007793A6 (fr) * 1993-12-24 1995-10-24 Centre Rech Metallurgique Procede et installation de traitement continu d'une bande d'acier galvanisee.
JPH08165550A (ja) * 1994-12-13 1996-06-25 Nippon Steel Corp 耐フレーキング性に優れた合金化溶融亜鉛めっき鋼板の製造方法
EP0823490B1 (fr) * 1996-02-22 2003-07-30 Sumitomo Metal Industries, Ltd. Tole d'acier recuit et procede de production

Also Published As

Publication number Publication date
DE19822156A1 (de) 1999-11-18
US20010035240A1 (en) 2001-11-01
JP2000026948A (ja) 2000-01-25
US6379481B2 (en) 2002-04-30
ES2192356T3 (es) 2003-10-01
CA2271816A1 (fr) 1999-11-16
ATE231191T1 (de) 2003-02-15
DE59904014D1 (de) 2003-02-20
EP0959145A1 (fr) 1999-11-24

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