EP3013994B1 - Diffusion of aluminium-silicon into a steel sheet web - Google Patents

Diffusion of aluminium-silicon into a steel sheet web Download PDF

Info

Publication number
EP3013994B1
EP3013994B1 EP14733592.1A EP14733592A EP3013994B1 EP 3013994 B1 EP3013994 B1 EP 3013994B1 EP 14733592 A EP14733592 A EP 14733592A EP 3013994 B1 EP3013994 B1 EP 3013994B1
Authority
EP
European Patent Office
Prior art keywords
furnace
sheet steel
steel web
web
steel sheet
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.)
Active
Application number
EP14733592.1A
Other languages
German (de)
French (fr)
Other versions
EP3013994A1 (en
Inventor
Rolf-Josef Schwartz
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.)
Schwartz GmbH
Original Assignee
Schwartz GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Schwartz GmbH filed Critical Schwartz GmbH
Priority to EP14733592.1A priority Critical patent/EP3013994B1/en
Publication of EP3013994A1 publication Critical patent/EP3013994A1/en
Application granted granted Critical
Publication of EP3013994B1 publication Critical patent/EP3013994B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/63—Continuous furnaces for strip or wire the strip being supported by a cushion of gas
    • 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
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
    • 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • 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
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/02—Pretreatment of the material to be coated
    • 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
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/28—Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
    • C23C10/34—Embedding in a powder mixture, i.e. pack cementation
    • C23C10/52—Embedding in a powder mixture, i.e. pack cementation more than one element being diffused in one step
    • 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
    • C23C10/00—Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/60—After-treatment
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B1/00—Shaft or like vertical or substantially vertical furnaces
    • F27B1/005—Shaft or like vertical or substantially vertical furnaces wherein no smelting of the charge occurs, e.g. calcining or sintering furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B1/00—Shaft or like vertical or substantially vertical furnaces
    • F27B1/10—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B1/20—Arrangements of devices for charging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/02—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity of multiple-track type; of multiple-chamber type; Combinations of furnaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/06—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated
    • F27B9/10—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity heated without contact between combustion gases and charge; electrically heated heated by hot air or gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/28—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity for treating continuous lengths of work
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/38—Arrangements of devices for charging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
    • F27B9/30—Details, accessories, or equipment peculiar to furnaces of these types
    • F27B9/39—Arrangements of devices for discharging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D3/0024—Charging; Discharging; Manipulation of charge of metallic workpieces
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/62—Quenching devices
    • C21D1/673—Quenching devices for die quenching
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite
    • 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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/009—Pearlite
    • 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
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/573—Continuous furnaces for strip or wire with cooling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D2003/0034—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities
    • F27D2003/0075—Charging or discharging vertically, e.g. through a bottom opening

Definitions

  • the invention relates to a device and a method for diffusing aluminum-silicon (Al-Si) into a surface of an Al-Si-coated steel sheet web, in which a high-melting aluminum-silicon-iron alloy is formed by the diffusion.
  • the aim is to reduce the fuel consumption of motor vehicles and to reduce CO 2 emissions, but at the same time to increase occupant safety.
  • body components with a favorable strength-to-weight ratio.
  • these components include, in particular, A and B pillars, side impact protection beams in doors, sills, frame parts, bumpers, cross beams for floor and roof, front and rear side members.
  • the body shell with a safety cage usually consists of a hardened steel sheet with a strength of approximately 1,500 MPa.
  • furnaces for heat treatment have prevailed for reasons of process reliability and economy.
  • the metal parts to be treated are continuously conveyed through the furnace.
  • chamber furnaces can also be used in which the metal parts are produced in batches placed in a chamber, warmed there and then removed again.
  • a blank is punched out of a sheet steel strip, cold formed and the component thus preformed is fed to the heat treatment. After the heat treatment, the hot component is fed to the press in an indirectly cooled tool. Then the components are trimmed again and sandblasted to remove any existing scaling.
  • a board is also punched out of a sheet steel strip, but there is no pre-deformation here, but the board is fed directly to the furnace. After the heat treatment, the hot plate is fed to the press and deformed in an indirectly water-cooled tool and at the same time press-hardened. The molded components are then trimmed again if necessary.
  • roller hearth furnaces have become established for both processes for reasons of process reliability and economy.
  • the walking beam furnace in which the metal parts are transported through the furnace by means of walking beams, can be cited as an alternative furnace design.
  • Multi-layer chamber furnaces are also becoming increasingly important.
  • continuous furnaces for this process are usually equipped with inlet and outlet locks, since uncoated components have to be heat-treated in the indirect process. To avoid scaling of the component surface, such an oven must be operated with protective gas. These inlet and outlet locks are used to prevent air from entering the furnace. Chamber furnaces for this process can also be equipped with a lock. With this type of furnace, however, it is also possible to exchange the atmosphere in the furnace chamber for each cycle. Continuous furnaces for this process must be equipped with a goods carrier return system to ensure the circulation of the goods carriers. Ceramic conveyor rollers are used in these ovens. Only the entry and exit tables and the goods carrier return conveyor are equipped with metallic conveyor rollers.
  • these ovens can be operated with a significantly lower energy input, since there are no goods carriers that can cool down on the return transport after the oven has passed through and therefore have to be heated up again in the oven when they are run again.
  • the direct method is therefore preferably used with the use of continuous furnaces.
  • the sheets used in vehicle construction should not rust if possible. Scaling should also be avoided during the processing process, since such scaling must be removed in a complex and costly manner for further processing, at the latest before the welding or painting process. Since untreated steel sheets would inevitably scale in the presence of oxygen at the high temperatures required for press hardening, it is common to use coated sheets and / or to carry out the heat treatment process in the absence of oxygen.
  • a device for heat treatment of metallic strips in a pass, in particular for operation under protective gas of low density is known.
  • the device has stabilizing nozzle systems which stabilize the course of the strip and which in the heating part and at least in the first part of the cooling effect the heat transfer predominantly with forced convection.
  • the belt is guided in the treatment part delimited by rollers without contact.
  • the band course has a concave curvature in the treatment area, at least in a partial area. The region of this concave curvature can take place in a fluid which is different from the fluid with which the band is blown in the heating part and at least in the first part of the cooling region.
  • Aluminum-silicon (Al-Si) coated sheets are usually used for press-hardened components for the automotive industry.
  • the coating prevents the sheets from rusting and prevents the hot sheets from scaling on the transfer from the furnace to the press.
  • the Al-Si of the coating diffuses into the steel surface when the board is heated to the hardening temperature and protects the base material against scaling.
  • Boron-alloyed tempering steels such as 22MnB5 (material number 1.5528) or 30MnB5 (material number 1.5531), have recently been used as the base material.
  • Al-Si diffusion coatings are in the documents WO 93/23247 and US 5,922,409
  • a major disadvantage of direct press hardening in the roller hearth furnaces described above lies in the fact that Al-Si-coated blanks are placed directly on the ceramic conveyor rollers, and this leads to strong thermo-chemical reactions between the Al-Si coating and the ceramic roll comes.
  • Another major disadvantage of the method described is the cycle time, since the majority of the furnace time is used to deposit the Al-Si melt the surface and diffuse into the substrate surface so that the desired welding, corrosion and paint adhesion properties are achieved.
  • rollers currently in use in roller hearth furnaces are hollow rollers made of sinter-mullite (3Al 2 0 3 ⁇ 2Si0 2 ) and solid rollers made of quartz.
  • the quartz material rolls consist of over 99% Si0 2 and have an application limit of approx. 1100 ° C with the disadvantage that they bend at approx. 700 ° C to 800 ° C due to their own weight.
  • Rolls made of sintered mullite can be used up to 1350 ° C without significant bending.
  • the great advantage of both materials is the high resistance to temperature changes. However, both materials have a very high affinity to react with molten aluminum to form different aluminum silicate or even silicide compounds.
  • the Al-Si coating causes the molten phase of the coating to pass through at about 670 ° C during heating to the approximately 930 ° C required for diffusion.
  • the short-term melting of the coating has proven to be very aggressive on the oven rolls and, under unfavorable circumstances, destroys them within a few days.
  • the object of the invention is to provide a method and a device in which aluminum-silicon can be diffused into a surface of a sheet steel sheet and wherein a sheet steel component which has been compression-hardened in the press hardening process can be produced from the sheet steel sheet thus treated, the disadvantages described being avoided.
  • this object is achieved by a method having the features of independent claim 1.
  • Advantageous developments of the method result from subclaims 2 to 8.
  • the object is further achieved by a device according to claim 9.
  • Advantageous embodiments of the device result from subclaims 10 to 16.
  • the method according to the invention for diffusing Al-Si into a surface of an Al-Si-coated sheet steel sheet is characterized by the following steps: First, the sheet steel sheet is fed to a furnace which can be heated to a diffusion temperature of 930 ° C to 950 ° C and then passed through the furnace which has been heated to a diffusion temperature without contact. The sheet steel sheet is heated to the diffusion temperature, with Al-Si diffusing into a surface of the sheet steel sheet. At the same time, iron also diffuses from the sheet steel substrate into the Al-Si layer on the surface of the sheet steel sheet. A high-melting aluminum-silicon-iron alloy is created on the surface of the sheet steel sheet.
  • the sheet steel sheet is then cooled at a speed of less than approximately 25K / sec, so that a ferrite / pearlite structure is created.
  • the result is a treated sheet steel sheet, from which a sheet steel component that is form-hardened by means of press hardening can be produced in a later process step.
  • a steel plate can first be cut from the treated soft steel sheet, which can then be heated to the martensite formation temperature for the press hardening process, for example in a conventional roller hearth furnace, without it becoming a liquid phase of Al-Si and thus one of the rolls of the Roller hearth stove comes damaging reaction.
  • Al-Si is diffused into both surfaces of a steel sheet web coated on both sides with Al-Si.
  • the sheet steel web is advantageously taken directly from a first sheet steel coil.
  • the coil form corresponds to the usual form of delivery of sheet steel sheeting.
  • the steel sheet web pretreated in the inventive method can also be further processed immediately, whereby the winding up to a second steel sheet coil can be omitted.
  • the steel sheet web is heated to diffusion temperature in a first furnace part. After the required diffusion time and a possible final annealing to achieve certain desired physical parameters, the steel sheet web is cooled in a second furnace part of the same furnace after the Al-Si has diffused into a surface of the steel sheet web to a temperature at which ferrite / pearlite structure is formed.
  • the cooling rate is less than 25K / sec. This enables the individual blanks to be cut later using the punching process.
  • the steel sheet web can then be quickly cooled to a handling temperature for better handling.
  • the sheet steel sheet is guided through the furnace without contact on a hot air cushion.
  • the hot air can also have a diffusion temperature so that Al-Si is diffused into both surfaces of the steel sheet web.
  • the sheet steel sheet floats on the hot air cushion contactlessly through the oven, so that no damaging Reaction of the melted Al-Si with support devices such as rollers or walking beams can take place.
  • the sheet steel sheet is guided through the furnace by applying a tensile force.
  • the pulling force can be via the pull-off means, for example a driven second reel on which the treated steel sheet web can be wound into a coil, in connection with a braked first reel from which the untreated Al-Si-coated steel sheet web is unwound from a coil. be applied.
  • the sheet steel sheet follows a rope line through the furnace, for example, it sags between the unwinding point from the first reel and the winding point on the second reel depending on the applied tensile force and the distance of the unwinding from the winding point.
  • the device for producing a hot air cushion can be dispensed with. This cable pull process can also be combined with the hot air cushion.
  • the furnace length is chosen longer. If the furnace length is longer, the tensile force applied to the sheet steel sheet must be increased. When combined with the hot air cushion, however, the pulling force can be reduced.
  • the furnace is arranged essentially vertically.
  • the sheet steel sheet is advantageously guided through the furnace from top to bottom.
  • This direction of implementation has advantages with regard to temperature control, since the first furnace region with the higher diffusion temperature is thus arranged above the second furnace region with the lower temperature, at which a ferritic / pearlitic structure is formed.
  • the inventive device for diffusing Al-Si into a surface of an Al-Si-coated sheet steel sheet is defined in the claims and characterized in that the Device has a furnace, the furnace having a first region that can be heated to the diffusion temperature, wherein the Al-Si-coated sheet steel sheet can be passed through the furnace without contact.
  • a sheet steel component that is form-hardened in the press hardening process can be produced from the sheet steel web treated in this way.
  • the furnace has a device for producing a hot air cushion, on which the sheet steel sheet can be passed through the furnace without contact.
  • the hot air can also have a diffusion temperature, so that Al-Si can be diffused into both surfaces of the steel sheet web.
  • the steel sheet web floats on the hot air cushion contactlessly through the furnace, so that no damaging reaction of melted Al-Si on supporting devices, such as rollers or walking beams, can take place.
  • the furnace has a hot air nozzle as a device for producing a hot air cushion.
  • the furnace has a device for applying a tensile force to the steel sheet web for the contactless passage of the steel sheet web through the furnace.
  • the sheet steel sheet is kept under tension so that it at least does not sag so far that it touches the furnace.
  • the cable can also be combined with the hot air cushion. This is particularly advantageous if the furnace is too long, so that the sheet steel sheet would sag too much despite the tensile force applied.
  • the combination of hot air cushion and cable pull can also reduce the tensile force so that no or only low stresses are introduced into the sheet steel sheet.
  • the furnace is arranged essentially vertically.
  • the Al-Si-coated sheet steel sheet can be passed through the furnace from top to bottom without contact, without the need for a hot air cushion or a cable.
  • this embodiment can also be applied with a tensile force and / or Hot air cushion can be combined, the hot air cushion can also be present on both sides of the sheet steel web.
  • the furnace further has a second furnace region arranged behind the first furnace region in the direction of passage of the steel sheet web, the steel sheet web being able to be cooled to a temperature at a rate of less than 25 K / sec during the passage through the second furnace region, at which soft ferritic / pearlitic structure.
  • the steel sheet web can be cooled to such a temperature by the provision of the second furnace area, the cooling rate of less than 25 K / sec being reliably maintained. This creates a soft ferrite / pearlite structure, which enables the individual blanks to be cut to size later using the stamping process.
  • the device also has a feed device for feeding the sheet steel sheet to the furnace and a removal device for pulling the sheet steel sheet out of the furnace.
  • a tension can be applied to the steel sheet web by the feed and withdrawal devices, so that it does not sag too much when the furnace is essentially horizontal and the tensile force does not exceed the tensile strength following a rope line.
  • the feed device has a first reel and the take-off device has a second reel.
  • a coil can be clamped onto the first reel as a standard form of delivery of sheet steel strips.
  • the second reel can rewind the pre-treated steel strip as a coil.
  • the second reel can also be omitted if the pretreated sheet steel strip is to be further processed immediately, for example fed to a punching device.
  • the furnace can be operated with a low dew point from -70 ° C to + 10 ° C, in particular from approx. + 5 ° C to + 10 ° C.
  • Fig. 1 shows a device according to the invention in a horizontal design.
  • the device has a first reel 210 with a first steel sheet coil 310 located thereon.
  • the first sheet steel coil 310 consists of a wound Al-Si-coated sheet steel sheet 300 in strip form.
  • a feed device can furthermore have guide rollers (not shown).
  • the furnace 100 has a first furnace region 110, which is heated to a temperature at which the Al-Si of the coating diffuses into the surface of the steel sheet web 300. At the same time, iron diffuses from the steel sheet substrate into the Al-Si.
  • a high-melting aluminum-silicon-iron alloy is created on the surface of the sheet steel sheet.
  • the furnace is heated via the heaters 150 and a hot air cushion 165, which is generated via hot air nozzles 160 under the sheet steel sheet.
  • the sheet steel sheet 300 floats on the hot air cushion 165 through the furnace 100 without touching it. Additional supporting or guiding elements, such as rollers or the like, are not required. As a result, no damaging reaction of melted Al-Si with these support and / or guide elements can take place.
  • the heaters 160 are gas burners. However, electric infrared heaters or hot air heaters are also conceivable, for example.
  • the length of the first furnace region is dimensioned as a function of the throughput speed of the steel sheet web 300 such that the steel sheet web is heated to the diffusion temperature of, for example, 930 ° C. to 950 ° C. and the required diffusion time remains at this temperature. Is also one Possible final glow time is taken into account when dimensioning the length of the first furnace area 110.
  • a second furnace region 120 follows the first furnace region 110 in the direction of passage of the steel sheet web.
  • the temperature control in the second furnace region 120 and the length of the second furnace region 120 are dimensioned such that the steel sheet web reaches the temperature range of ferrite with a cooling rate of less than 25 K / sec. / Perlite structure is cooled so that a board can then be punched out of the sheet steel sheet.
  • An extraction device with a second reel 220 is connected to the second furnace region 120.
  • the second reel 220 also rotates clockwise, as a result of which the pretreated sheet steel web is rewound into a second coil 320.
  • a pull-off device can also have guide rollers (not shown).
  • Fig. 2 shows a device according to the invention in a vertical design.
  • the furnace 100 is designed as a tower in a substantially vertical direction.
  • the sheet steel sheet 300 is passed through the furnace 100 from top to bottom. Due to the vertical construction, no measures such as the provision of hot air cushions or cable pulling devices are necessary in order to guide the steel sheet web through the furnace 100 without contact.
  • the direction of passage from top to bottom facilitates temperature control in the furnace, since the cooler second furnace region 120 is located below the first furnace region 110 heated to the diffusion temperature.
  • 100 heaters 150 are provided on both sides of the furnace for homogeneous heating of both surfaces of the steel sheet strip 300. As in the case of the horizontal arrangement, these can be designed, for example, as gas burners or as hot air heaters or, for example, electric radiant heaters.
  • Feeding and withdrawing device for the steel strip 300 are constructed analogously to the horizontal embodiment.

Description

Die Erfindung betrifft eine Vorrichtung und ein Verfahren zum Eindiffundieren von Aluminium-Silizium (Al-Si) in eine Oberfläche einer Al-Si-beschichteten Stahlblechbahn, bei der sich durch die Eindiffundierung eine hochschmelzende Aluminium-Silizium-Eisen-Legierung bildet.The invention relates to a device and a method for diffusing aluminum-silicon (Al-Si) into a surface of an Al-Si-coated steel sheet web, in which a high-melting aluminum-silicon-iron alloy is formed by the diffusion.

In der Technik besteht bei vielen Anwendungsfällen in unterschiedlichen Branchen der Wunsch nach hochfesten Metallblechteilen bei geringem Teilegewicht. Beispielsweise ist es in der Fahrzeugindustrie das Bestreben, den Kraftstoffverbrauch von Kraftfahrzeugen zu reduzieren und den CO2-Ausstoß zu senken, dabei aber gleichzeitig die Insassensicherheit zu erhöhen. Es besteht daher ein stark zunehmender Bedarf an Karosseriebauteilen mit einem günstigen Verhältnis von Festigkeit zu Gewicht. Zu diesen Bauteilen gehören insbesondere A- und B-Säulen, Seitenaufprallschutzträger in Türen, Schweller, Rahmenteile, Stoßstangenfänger, Querträger für Boden und Dach, vordere und hintere Längsträger. Bei modernen Kraftfahrzeugen besteht die Rohkarosse mit einem Sicherheitskäfig üblicherweise aus einem gehärteten Stahlblech mit ca. 1.500MPa Festigkeit.In technology, there is a desire for high-strength sheet metal parts with a low part weight in many applications in different industries. For example, in the automotive industry, the aim is to reduce the fuel consumption of motor vehicles and to reduce CO 2 emissions, but at the same time to increase occupant safety. There is therefore a rapidly increasing need for body components with a favorable strength-to-weight ratio. These components include, in particular, A and B pillars, side impact protection beams in doors, sills, frame parts, bumpers, cross beams for floor and roof, front and rear side members. In modern motor vehicles, the body shell with a safety cage usually consists of a hardened steel sheet with a strength of approximately 1,500 MPa.

Dies wird üblicherweise durch den Prozess des sogenannten Presshärtens erreicht. Dabei wird ein Stahlblechteil auf etwa 800 - 1000°C erwärmt und anschließend in einem gekühlten Werkzeug verformt und abgeschreckt. Die Festigkeit des Bauteils nimmt dadurch bis auf etwa das Dreifache zu.This is usually achieved through the process of so-called press hardening. A sheet steel part is heated to approximately 800 - 1000 ° C and then deformed and quenched in a cooled tool. This increases the strength of the component up to about three times.

Aus Gründen der Prozesssicherheit und der Wirtschaftlichkeit haben sich Durchlauföfen für die Wärmebehandlung durchgesetzt. Dabei werden die zu behandelnden Metallteile kontinuierlich durch den Ofen hindurchgefördert. Alternativ können auch Kammeröfen eingesetzt werden, in denen die Metallteile chargenweise in eine Kammer verbracht, dort erwärmt und anschließend wieder entnommen werden.Continuous furnaces for heat treatment have prevailed for reasons of process reliability and economy. The metal parts to be treated are continuously conveyed through the furnace. Alternatively, chamber furnaces can also be used in which the metal parts are produced in batches placed in a chamber, warmed there and then removed again.

Beim Presshärten unterscheidet man grundsätzlich das direkte und das indirekte Verfahren.A basic distinction is made between direct and indirect processes in press hardening.

Beim indirekten Verfahren wird eine Platine aus einem Stahlblechband herausgestanzt, kalt verformt und das so vorgeformte Bauteil der Wärmebehandlung zugeführt. Nach der Wärmebehandlung wird das heiße Bauteil der Presse zugeführt in einem indirekt gekühlten Werkzeug pressgehärtet. Anschließend werden die Bauteile noch einmal getrimmt und zur Entfernung eventuell vorhandener Verzunderungen gesandstrahlt.In the indirect process, a blank is punched out of a sheet steel strip, cold formed and the component thus preformed is fed to the heat treatment. After the heat treatment, the hot component is fed to the press in an indirectly cooled tool. Then the components are trimmed again and sandblasted to remove any existing scaling.

Beim direkten Verfahren wird ebenfalls eine Platine aus einem Stahlblechband herausgestanzt, allerdings findet hier keine Vorverformung statt, sondern die Platine wird direkt dem Ofen zugeführt. Nach der Wärmebehandlung wird die heiße Platine der Presse zugeführt und in einem indirekt wassergekühlten Werkzeug verformt und gleichzeitig pressgehärtet. Anschließend werden die geformten Bauteile noch einmal erforderlichenfalls getrimmt.In the direct method, a board is also punched out of a sheet steel strip, but there is no pre-deformation here, but the board is fed directly to the furnace. After the heat treatment, the hot plate is fed to the press and deformed in an indirectly water-cooled tool and at the same time press-hardened. The molded components are then trimmed again if necessary.

Für beide Verfahren haben sich aus Gründen der Prozesssicherheit und der Wirtschaftlichkeit sogenannte Rollenherdöfen durchgesetzt. Als eine alternative Ofenbauform kann beispielsweise der Hubbalkenofen genannt werden, bei dem die Metallteile mittels Hubbalken durch den Ofen transportiert werden. Auch Mehrlagenkammeröfen finden zunehmend Bedeutung.So-called roller hearth furnaces have become established for both processes for reasons of process reliability and economy. The walking beam furnace, in which the metal parts are transported through the furnace by means of walking beams, can be cited as an alternative furnace design. Multi-layer chamber furnaces are also becoming increasingly important.

Da die Bauteile beim indirekten Prozess vorgeformt sind, müssen sie auf Grund ihrer komplexen Form auf Warenträgern durch den Ofen gefördert bzw. in die Ofenkammer verbracht werden. Weiterhin sind Durchlauföfen für dieses Verfahren üblicherweise mit Ein- und Auslaufschleusen ausgerüstet, da beim indirekten Verfahren unbeschichtete Bauteile wärmebehandelt werden müssen. Um eine Verzunderung der Bauteiloberfläche zu vermeiden, muss ein solcher Ofen mit Schutzgas betrieben werden. Diese Ein- und Auslaufschleusen dienen zur Vermeidung des Lufteintrittes in den Ofen. Kammeröfen für dieses Verfahren können ebenfalls mit einer Schleuse ausgerüstet sein. Es ist bei dieser Ofenbauform aber auch möglich, die Atmosphäre in der Ofenkammer für jeden Zyklus auszutauschen. Durchlauföfen für dieses Verfahren müssen mit einem Warenträger-Rückfördersystem ausgestattet werden, um den Kreislauf der Warenträger zu gewährleisten. In diesen Öfen werden keramische Förderrollen eingesetzt. Nur die Ein- und Auslauftische sowie der Warenträgerrückförderer sind mit metallischen Förderrollen ausgestattet.Since the components are preformed in the indirect process, their complex shape means that they have to be conveyed through the furnace on product carriers or brought into the furnace chamber. Furthermore, continuous furnaces for this process are usually equipped with inlet and outlet locks, since uncoated components have to be heat-treated in the indirect process. To avoid scaling of the component surface, such an oven must be operated with protective gas. These inlet and outlet locks are used to prevent air from entering the furnace. Chamber furnaces for this process can also be equipped with a lock. With this type of furnace, however, it is also possible to exchange the atmosphere in the furnace chamber for each cycle. Continuous furnaces for this process must be equipped with a goods carrier return system to ensure the circulation of the goods carriers. Ceramic conveyor rollers are used in these ovens. Only the entry and exit tables and the goods carrier return conveyor are equipped with metallic conveyor rollers.

Bei Durchlauföfen für das direkte Verfahren entfällt der Einsatz von Warenträgern. Daher ist die Konstruktion etwas einfacher als die der Durchlauföfen für den indirekten Prozess. Statt mittels Warenträger befördert zu werden, werden die Platinen beim direkten Verfahren unmittelbar auf keramische Förderrollen aufgelegt und durch den Ofen gefördert. Diese Öfen können mit und ohne Schutzgas betrieben werden. Auch hier ist das Ofengehäuse serienmäßig gasdicht geschweißt. Ein weiterer Vorteil dieser Bauart ist in dem positiven Effekt der Förderrolle auf die gleichmäßige Erwärmung der zu behandelnden Metallteile zu sehen: Die durch die Ofenheizung mit aufgewärmten ortsfesten Rollen erwärmen über Strahlung und Wärmeleitung das auf ihnen transportierte und daher mit ihnen in Kontakt stehende Metallteil zusätzlich auf. Darüber hinaus sind diese Öfen mit einem deutlich niedrigeren Energieeinsatz zu betreiben, da es keine Warenträger gibt, die auf dem Rücktransport nach dem Ofendurchlauf auskühlen können und daher im Ofen bei einem erneuten Durchlauf wieder mit aufgeheizt werden müssen. Das direkte Verfahren wird daher mit der Verwendung von Durchlauföfen bevorzugt verwendet.In the case of continuous furnaces for direct processing, there is no need to use product carriers. Therefore, the design is somewhat simpler than that of the continuous furnace for the indirect process. Instead of being transported by means of a goods carrier, the blanks are placed directly on ceramic conveyor rollers and conveyed through the furnace. These furnaces can be operated with and without protective gas. The furnace housing is welded gas-tight as standard. Another advantage of this design can be seen in the positive effect of the conveyor roller on the uniform heating of the metal parts to be treated: The stationary rollers heated by the furnace heating with radiation and heat conduction also heat up the metal part transported on them and therefore in contact with them . In addition, these ovens can be operated with a significantly lower energy input, since there are no goods carriers that can cool down on the return transport after the oven has passed through and therefore have to be heated up again in the oven when they are run again. The direct method is therefore preferably used with the use of continuous furnaces.

Die im Fahrzeugbau verwendeten Bleche sollen möglichst nicht rosten. Auch soll eine Verzunderung während des Bearbeitungsprozesses vermieden werden, da solche Verzunderungen zur Weiterverarbeitung, spätestens vor dem Schweiß- oder Lackierprozess, aufwändig und kostspielig entfernt werden müssen. Da unbehandelte Stahlbleche aber bei den beim Presshärten erforderlichen hohen Temperaturen unter Anwesenheit von Sauerstoff unweigerlich verzundern würden, ist es üblich, beschichtete Bleche zu verwenden und / oder den Wärmebehandlungsprozess bei Abwesenheit von Sauerstoff durchzuführen.The sheets used in vehicle construction should not rust if possible. Scaling should also be avoided during the processing process, since such scaling must be removed in a complex and costly manner for further processing, at the latest before the welding or painting process. Since untreated steel sheets would inevitably scale in the presence of oxygen at the high temperatures required for press hardening, it is common to use coated sheets and / or to carry out the heat treatment process in the absence of oxygen.

Aus dem deutschen Patent DE 103 03 228 B3 ist eine Vorrichtung zur Wärmebehandlung metallischer Bänder im Durchlauf, insbesondere zum Betrieb unter Schutzgas geringer Dichte, bekannt. Die Vorrichtung weist den Bandverlauf stabilisierende Stabilisierungsdüsensysteme auf, die im Erwärmungsteil und zumindest im ersten Teil der Abkühlung den Wärmeübergang überwiegend mit erzwungener Konvektion bewirken. Das Band wird in dem durch Rollen eingegrenzten Behandlungsteil berührungsfrei geführt. Der Bandverlauf weist in dem Behandlungsbereich, von oben betrachtet, zumindest in einem Teilbereich eine konkave Krümmung auf. Der Bereich dieser konkaven Krümmung kann in einem Fluid erfolgen, das von dem Fluid, mit dem das Band im Erwärmungsteil und zumindest im ersten Teil des Kühlbereichs beblasen wird, unterschiedlich ist. Üblicherweise werden für pressgehärtete Bauteile für die Automobilindustrie Aluminium-Silizium-(Al-Si-)beschichtete Bleche verwendet. Die Beschichtung verhindert das Rosten der Bleche, ebenso wie ein Verzundern der heißen Bleche auf dem Transfer von dem Ofen zur Presse. Das Al-Si des Überzugs diffundiert bei der Aufheizung der Platine auf Härtetemperatur in die Stahloberfläche und schütz den Grundwerkstoff gegen Verzunderung. Als Grundwerkstoff kommen neuerdings borlegierte Vergütungsstähle, wie beispielsweise 22MnB5 (Werkstoffnummer 1.5528) oder 30MnB5 (Werkstoffnummer 1.5531), zum Einsatz.From the German patent DE 103 03 228 B3 a device for heat treatment of metallic strips in a pass, in particular for operation under protective gas of low density, is known. The device has stabilizing nozzle systems which stabilize the course of the strip and which in the heating part and at least in the first part of the cooling effect the heat transfer predominantly with forced convection. The belt is guided in the treatment part delimited by rollers without contact. When viewed from above, the band course has a concave curvature in the treatment area, at least in a partial area. The region of this concave curvature can take place in a fluid which is different from the fluid with which the band is blown in the heating part and at least in the first part of the cooling region. Aluminum-silicon (Al-Si) coated sheets are usually used for press-hardened components for the automotive industry. The coating prevents the sheets from rusting and prevents the hot sheets from scaling on the transfer from the furnace to the press. The Al-Si of the coating diffuses into the steel surface when the board is heated to the hardening temperature and protects the base material against scaling. Boron-alloyed tempering steels, such as 22MnB5 (material number 1.5528) or 30MnB5 (material number 1.5531), have recently been used as the base material.

Al-Si Diffusionsbeschichtungen sind in den Dokumenten WO 93/23247 und US 5,922,409 offenbart.Ein großer Nachteil des direkten Presshärtens in den oben beschriebenen Rollenherdöfen liegt darin begründet, dass Al-Si-beschichtete Platinen direkt auf die keramischen Förderrollen aufgelegt werden, und es dadurch zu starken thermo-chemischen Reaktionen zwischen der Al-Si-Beschichtung und den keramischen Rollen kommt. Ein weiterer großer Nachteil des beschriebenen Verfahrens liegt in der Zykluszeit, da die überwiegende Ofenzeit dazu gebraucht wird, das Al-Si auf der Oberfläche zu schmelzen und in die Substratoberfläche zu diffundieren, damit die gewünschten Schweiß-, Korrosions- und Lackhafteigenschaften erreicht werden.Al-Si diffusion coatings are in the documents WO 93/23247 and US 5,922,409 A major disadvantage of direct press hardening in the roller hearth furnaces described above lies in the fact that Al-Si-coated blanks are placed directly on the ceramic conveyor rollers, and this leads to strong thermo-chemical reactions between the Al-Si coating and the ceramic roll comes. Another major disadvantage of the method described is the cycle time, since the majority of the furnace time is used to deposit the Al-Si melt the surface and diffuse into the substrate surface so that the desired welding, corrosion and paint adhesion properties are achieved.

Bei den derzeit in Rollenherdöfen im Einsatz befindlichen Rollen handelt es sich um Hohlrollen aus dem Werkstoff Sinter-Mullit (3Al203 · 2Si02) und Vollrollen aus Quarzgut. Die Quarzgut-Rollen bestehen zu über 99 % aus Si02 und haben eine Anwendungsgrenze von ca. 1100°C mit dem Nachteil, dass sie sich bei ca. 700°C bis 800°C durch das Eigengewicht verbiegen. Rollen aus Sinter-Mullit können belastet bis 1350°C eingesetzt werden, ohne dass es zu signifikanten Verbiegungen kommt. Der große Vorteil beider Werkstoffe ist die hohe Temperaturwechselbeständigkeit. Allerdings haben beide Werkstoffe eine sehr hohe Affinität, mit geschmolzenem Aluminium zu unterschiedlichen Aluminium-Silikat oder gar Silizid-Verbindungen zu reagieren. Durch die Al-Si-Beschichtung kommt es während der Erwärmung auf die zur Diffusion erforderlichen circa 930°C zu einem Durchschreiten einer schmelzflüssigen Phase der Beschichtung bei circa 670°C. Die kurzzeitige Schmelze der Beschichtung hat sich als sehr aggressiv auf die Ofenrollen herausgestellt und zerstört diese unter ungünstigen Umständen innerhalb weniger Tage.The rollers currently in use in roller hearth furnaces are hollow rollers made of sinter-mullite (3Al 2 0 3 · 2Si0 2 ) and solid rollers made of quartz. The quartz material rolls consist of over 99% Si0 2 and have an application limit of approx. 1100 ° C with the disadvantage that they bend at approx. 700 ° C to 800 ° C due to their own weight. Rolls made of sintered mullite can be used up to 1350 ° C without significant bending. The great advantage of both materials is the high resistance to temperature changes. However, both materials have a very high affinity to react with molten aluminum to form different aluminum silicate or even silicide compounds. The Al-Si coating causes the molten phase of the coating to pass through at about 670 ° C during heating to the approximately 930 ° C required for diffusion. The short-term melting of the coating has proven to be very aggressive on the oven rolls and, under unfavorable circumstances, destroys them within a few days.

Aufgabe der Erfindung ist es, ein Verfahren und eine Vorrichtung anzugeben, bei dem Aluminium-Silizium in eine Oberfläche einer Stahlblechbahn eindiffundierbar ist und wobei aus der so behandelten Stahlblechbahn ein im Presshärteverfahren formgehärtetes Stahlblechbauteil herstellbar ist, wobei die beschriebenen Nachteile vermieden werden.The object of the invention is to provide a method and a device in which aluminum-silicon can be diffused into a surface of a sheet steel sheet and wherein a sheet steel component which has been compression-hardened in the press hardening process can be produced from the sheet steel sheet thus treated, the disadvantages described being avoided.

Erfindungsgemäß wird diese Aufgabe durch ein Verfahren mit den Merkmalen des unabhängigen Anspruches 1 gelöst. Vorteilhafte Weiterbildungen des Verfahrens ergeben sich aus den Unteransprüchen 2 bis 8. Die Aufgabe wird ferner durch eine Vorrichtung nach Anspruch 9 gelöst. Vorteilhafte Ausführungsformen der Vorrichtung ergeben sich aus den Unteransprüchen10 bis 16.According to the invention, this object is achieved by a method having the features of independent claim 1. Advantageous developments of the method result from subclaims 2 to 8. The object is further achieved by a device according to claim 9. Advantageous embodiments of the device result from subclaims 10 to 16.

Das Erfindungsgemäße Verfahren zum Eindiffundieren von Al-Si in eine Oberfläche einer Al-Si-beschichteten Stahlblechbahn zeichnet sich durch die folgenden Schritte aus:
Zunächst wird die Stahlblechbahn einem auf Diffusionstemperatur von 930°C bis 950°C aufheizbaren Ofen zugeführt und anschließend durch den auf Diffusionstemperatur aufgeheizten Ofen berührungslos hindurchgeführt. Dabei wird die Stahlblechbahn auf Diffusionstemperatur aufgeheizt, wobei Al-Si in eine Oberfläche der Stahlblechbahn eindiffundiert. Gleichzeitig diffundiert auch Eisen aus dem Stahlblechsubstrat in die Al-Si-Schicht auf der Oberfläche der Stahlblechbahn ein. Es entsteht eine hochschmelzende Aluminium-Silizium-Eisen-Legierung an der Oberfläche der Stahlblechbahn. Anschließend wird die Stahlblechbahn mit einer Geschwindigkeit von weniger als circa 25K/sec abgekühlt, so dass ein Ferrit-/Perlitgefüge entsteht. Dabei entsteht eine behandelte Stahlblechbahn, aus der in einem späteren Prozessschritt ein mittels Presshärteverfahren formgehärtetes Stahlblechbauteil herstellbar ist. Beispielsweise kann in einem Stanzverfahren zunächst eine Stahlblechplatine aus der behandelten weichen Stahlblechbahn geschnitten werden, die dann für das Presshärteverfahren beispielsweise in einem üblichen Rollenherdofen auf Martensitbildungstemperatur aufgeheizt werden kann, ohne dass es zu einer flüssigen Phase des Al-Si und damit zu einer die Rollen des Rollenherdofens schädigenden Reaktion kommt.The method according to the invention for diffusing Al-Si into a surface of an Al-Si-coated sheet steel sheet is characterized by the following steps:
First, the sheet steel sheet is fed to a furnace which can be heated to a diffusion temperature of 930 ° C to 950 ° C and then passed through the furnace which has been heated to a diffusion temperature without contact. The sheet steel sheet is heated to the diffusion temperature, with Al-Si diffusing into a surface of the sheet steel sheet. At the same time, iron also diffuses from the sheet steel substrate into the Al-Si layer on the surface of the sheet steel sheet. A high-melting aluminum-silicon-iron alloy is created on the surface of the sheet steel sheet. The sheet steel sheet is then cooled at a speed of less than approximately 25K / sec, so that a ferrite / pearlite structure is created. The result is a treated sheet steel sheet, from which a sheet steel component that is form-hardened by means of press hardening can be produced in a later process step. For example, in a stamping process, a steel plate can first be cut from the treated soft steel sheet, which can then be heated to the martensite formation temperature for the press hardening process, for example in a conventional roller hearth furnace, without it becoming a liquid phase of Al-Si and thus one of the rolls of the Roller hearth stove comes damaging reaction.

In einer vorteilhaften Ausführungsform des Verfahrens wird Al-Si in beide Oberflächen einer beidseitig mit Al-Si beschichteten Stahblechbahn eindiffundiert.In an advantageous embodiment of the method, Al-Si is diffused into both surfaces of a steel sheet web coated on both sides with Al-Si.

Vorteilhafterweise wird die Stahlblechbahn direkt von einem ersten Stahlblechcoil entnommen. Dabei entspricht die Coilform der üblichen Lieferform von Stahlblechbahnen.The sheet steel web is advantageously taken directly from a first sheet steel coil. The coil form corresponds to the usual form of delivery of sheet steel sheeting.

Weiterhin hat es sich als vorteilhaft erwiesen, dass die Stahlblechbahn nach der Durchführung durch den Ofen und langsamen Abkühlen auf eine Temperatur, bei der sich weiches Ferrit-/Perlit-Gefüge bildet, zu einem zweiten Stahlblechcoil aufgewickelt wird. Durch die Aufwicklung lässt sich das Eindiffundieren des Al-Si von dem nächsten Prozessschritt, beispielsweise dem Ausstanzen von Platinen, entkoppeln, so dass Zykluszeiten nicht aufeinander abgestimmt werden müssen. Die in dem erfinderischen Verfahren vorbehandelte Stahlblechbahn kann aber alternativ auch sogleich weiterverarbeitet werden, wobei die Aufwicklung zu einem zweiten Stahlblechcoil entfallen kann.Furthermore, it has proven to be advantageous for the steel sheet web to be wound up into a second steel sheet coil after it has been passed through the oven and slowly cooled to a temperature at which a soft ferrite / pearlite structure is formed. The winding allows the diffusion of the Al-Si to be decoupled from the next process step, for example punching out printed circuit boards, so that cycle times do not have to be coordinated. Alternatively, the steel sheet web pretreated in the inventive method can also be further processed immediately, whereby the winding up to a second steel sheet coil can be omitted.

In einer weiteren vorteilhaften Ausführungsform wird die Stahlblechbahn in einem ersten Ofenteil auf Diffusionstemperatur aufgeheizt. Nach Erreichen der erforderlichen Diffusionszeit und einem eventuellen Schlussglühen zum Erreichen bestimmter gewünschter physikalischer Parameter wird die Stahlblechbahn in einem zweiten Ofenteil desselben Ofens nach dem Eindiffundieren des Al-Si in eine Oberfläche der Stahlblechbahn auf eine Temperatur abgekühlt, bei der sich Ferrit-/Perlitgefüge bildet. Dabei beträgt die Abkühlgeschwindigkeit weniger als 25K/sec. Somit wird ein späteres Zuschneiden der Einzelplatinen im Stanzverfahren möglich. Zum besseren Handling kann die Stahlblechbahn anschließend schnell auf eine Handlingstemperatur weiter abgekühlt werden.In a further advantageous embodiment, the steel sheet web is heated to diffusion temperature in a first furnace part. After the required diffusion time and a possible final annealing to achieve certain desired physical parameters, the steel sheet web is cooled in a second furnace part of the same furnace after the Al-Si has diffused into a surface of the steel sheet web to a temperature at which ferrite / pearlite structure is formed. The cooling rate is less than 25K / sec. This enables the individual blanks to be cut later using the punching process. The steel sheet web can then be quickly cooled to a handling temperature for better handling.

In einer besonders vorteilhaften Ausführungsform wird die Stahlblechbahn auf einem Heißluftkissen berührungsfrei durch den Ofen geführt. Dabei kann die Heißluft ebenfalls Diffusionstemperatur aufweisen, so dass Al-Si in beide Oberflächen der Stahlblechbahn eindiffundiert wird. Auf dem Heißluftkissen schwebt die Stahlblechbahn dabei berührungslos durch den Ofen, so dass keine schädigende Reaktion des aufgeschmolzenen Al-Si mit Trageinrichtungen, wie beispielsweise Rollen oder Hubbalken, stattfinden kann.In a particularly advantageous embodiment, the sheet steel sheet is guided through the furnace without contact on a hot air cushion. The hot air can also have a diffusion temperature so that Al-Si is diffused into both surfaces of the steel sheet web. The sheet steel sheet floats on the hot air cushion contactlessly through the oven, so that no damaging Reaction of the melted Al-Si with support devices such as rollers or walking beams can take place.

In einer alternativen Ausführungsform wird die Stahlblechbahn mittels Aufbringens einer Zugkraft durch den Ofen geführt. Die Zugkraft kann dabei über das Abzugsmittel, beispielsweise eine angetriebene zweite Haspel, auf der die behandelte Stahlblechbahn zu einem Coil aufgewickelt werden kann, in Verbindung mit einer gebremsten ersten Haspel, von der die unbehandelte Al-Si-beschichte Stahlblechbahn von einem Coil abgewickelt wird, aufgebracht werden. Die Stahlblechbahn folgt dabei einer Seillinie durch den Ofen, wobei sie beispielsweise zwischen dem Abwickelpunkt von der ersten Haspel und dem Aufwickelpunkt auf der zweiten Haspel in Abhängigkeit von der aufgebrachten Zugkraft und dem Abstand des Abwickel- von dem Aufwickelpunkt durchhängt. Dabei kann auf die Vorrichtung zur Erzeugung eines Heißluftkissens verzichtet werden. Dieses Seilzugverfahren kann aber auch mit dem Heißluftkissen kombiniert werden. Dies ist besonders dann von Vorteil, wenn beispielsweise aus Gründen des schnelleren Durchfahrens des Ofens bei gleichzeitiger Konstanthaltung der Diffusionszeit und einer eventuellen Schlussglühzeit und der langsamen Abkühlung mit einer Abkühlgeschwindigkeit von unter 25K/sec auf eine Temperatur, bei der sich Ferrit-/Perlitgefüge bildet, die Ofenlänge länger gewählt wird. Bei einer größeren Ofenlänge muss die auf die Stahlblechbahn aufgebrachte Zugkraft vergrößert werden. Bei der Kombination mit dem Heißluftkissen kann die Zugkraft hingegen verringert werden.In an alternative embodiment, the sheet steel sheet is guided through the furnace by applying a tensile force. The pulling force can be via the pull-off means, for example a driven second reel on which the treated steel sheet web can be wound into a coil, in connection with a braked first reel from which the untreated Al-Si-coated steel sheet web is unwound from a coil. be applied. The sheet steel sheet follows a rope line through the furnace, for example, it sags between the unwinding point from the first reel and the winding point on the second reel depending on the applied tensile force and the distance of the unwinding from the winding point. The device for producing a hot air cushion can be dispensed with. This cable pull process can also be combined with the hot air cushion. This is particularly advantageous if, for example, for reasons of faster passage through the furnace while keeping the diffusion time constant and a possible final annealing time and slow cooling with a cooling rate of less than 25K / sec to a temperature at which ferrite / pearlite structure forms, the furnace length is chosen longer. If the furnace length is longer, the tensile force applied to the sheet steel sheet must be increased. When combined with the hot air cushion, however, the pulling force can be reduced.

In einer weiteren besonders vorteilhaften Ausführungsform ist der Ofen im Wesentlichen vertikal angeordnet. Dabei wird die Stahlblechbahn vorteilhafterweise von oben nach unten durch den Ofen geführt. Diese Durchführungsrichtung weist Vorteile bezüglich der Temperaturführung auf, da der erste Ofenbereich mit der höheren Diffusionstemperatur auf diese Weise oberhalb des zweiten Ofenbereichs mit der niedrigeren Temperatur, bei der sich ein ferritisches/perlitsches Gefüge bildet, angeordnet ist. Es ist aber auch möglich, die Durchführungsrichtung der Stahlblechbahn von unten nach oben zu wählen.In a further particularly advantageous embodiment, the furnace is arranged essentially vertically. The sheet steel sheet is advantageously guided through the furnace from top to bottom. This direction of implementation has advantages with regard to temperature control, since the first furnace region with the higher diffusion temperature is thus arranged above the second furnace region with the lower temperature, at which a ferritic / pearlitic structure is formed. However, it is also possible to choose the direction of passage of the sheet steel sheet from bottom to top.

Die erfinderische Vorrichtung zum Eindiffundieren von Al-Si in eine Oberfläche einer Al-Si-beschichteten Stahlblechbahn ist in den Ansprüchen definiert und dadurch gekennzeichnet, dass die Vorrichtung einen Ofen aufweist, wobei der Ofen einen auf Diffusionstemperatur aufheizbaren ersten Bereich aufweist, wobei die Al-Si-beschichteten Stahlblechbahn berührungslos durch den Ofen hindurchführbar ist. Aus der so behandelten Stahlblechbahn ist ein im Presshärteverfahren formgehärtetes Stahlblechbauteil herstellbar.The inventive device for diffusing Al-Si into a surface of an Al-Si-coated sheet steel sheet is defined in the claims and characterized in that the Device has a furnace, the furnace having a first region that can be heated to the diffusion temperature, wherein the Al-Si-coated sheet steel sheet can be passed through the furnace without contact. A sheet steel component that is form-hardened in the press hardening process can be produced from the sheet steel web treated in this way.

In einer vorteilhaften Ausführungsform weist der Ofen eine Vorrichtung zur Erzeugung eines Heißluftkissens auf, auf dem die Stahlblechbahn berührungslos durch den Ofen hindurchführbar ist. Dabei kann die Heißluft ebenfalls Diffusionstemperatur aufweisen, so dass Al-Si in beide Oberflächen der Stahlblechbahn eindiffundierbar ist. Auf dem Heißluftkissen schwebt die Stahlblechbahn dabei berührungslos durch den Ofen, so dass keine schädigende Reaktion von aufgeschmolzenem Al-Si an Trageinrichtungen, wie beispielsweise Rollen oder Hubbalken, stattfinden kann.In an advantageous embodiment, the furnace has a device for producing a hot air cushion, on which the sheet steel sheet can be passed through the furnace without contact. The hot air can also have a diffusion temperature, so that Al-Si can be diffused into both surfaces of the steel sheet web. The steel sheet web floats on the hot air cushion contactlessly through the furnace, so that no damaging reaction of melted Al-Si on supporting devices, such as rollers or walking beams, can take place.

In einer weiteren vorteilhaften Ausführungsform weist der Ofen als Vorrichtung zur Erzeugung eines Heißluftkissens eine Heißluftdüse auf.In a further advantageous embodiment, the furnace has a hot air nozzle as a device for producing a hot air cushion.

In einer alternativen Ausführungsform weist der Ofen eine Vorrichtung zur Aufbringung einer Zugkraft auf die Stahlblechbahn zum berührungslosen Hindurchführen der Stahlblechbahn durch den Ofen auf. Dabei wird die Stahlblechbahn so unter Spannung gehalten, dass sie zumindest nicht soweit durchhängt, dass sie den Ofen berührt. Der Seilzug kann aber auch mit dem Heißluftkissen kombiniert werden. Dies ist besonders dann von Vorteil, wenn der Ofen zu lang ist, so dass die Stahlblechbahn trotz der aufgebrachten Zugkraft zu weit durchhängen würde. Dabei kann bei der Kombination von Heißluftkissen und Seilzug die Zugkraft auch verringert werden, so dass keine oder nur geringe Spannungen in die Stahlblechbahn eingebracht werden.In an alternative embodiment, the furnace has a device for applying a tensile force to the steel sheet web for the contactless passage of the steel sheet web through the furnace. The sheet steel sheet is kept under tension so that it at least does not sag so far that it touches the furnace. The cable can also be combined with the hot air cushion. This is particularly advantageous if the furnace is too long, so that the sheet steel sheet would sag too much despite the tensile force applied. The combination of hot air cushion and cable pull can also reduce the tensile force so that no or only low stresses are introduced into the sheet steel sheet.

In einer weiteren besonders vorteilhaften Ausführungsform ist der Ofen im Wesentlichen vertikal angeordnet. Dabei ist die Al-Si-beschichtete Stahlblechbahn berührungslos von oben nach unten durch den Ofen hindurchführbar, ohne dass es eines Heißluftkissens oder eines Seilzugs bedarf. Trotzdem kann auch diese Ausführungsform sowohl mit dem Aufbringen einer Zugkraft und/oder einem Heißluftkissen kombiniert werden, wobei das Heißluftkissen auch beidseitig der Stahlblechbahn vorliegen kann.In a further particularly advantageous embodiment, the furnace is arranged essentially vertically. The Al-Si-coated sheet steel sheet can be passed through the furnace from top to bottom without contact, without the need for a hot air cushion or a cable. Nevertheless, this embodiment can also be applied with a tensile force and / or Hot air cushion can be combined, the hot air cushion can also be present on both sides of the sheet steel web.

Erfindungsgemäß weist der Ofen weiterhin einen in Durchführungsrichtung der Stahlblechbahn hinter dem ersten Ofenbereich angeordneten zweiten Ofenbereich auf, wobei die Stahlblechbahn während des Hindurchführens durch den zweiten Ofenbereich mit einer Geschwindigkeit von weniger als 25K/sec auf eine Temperatur abkühlbar ist, bei der sich weiches ferritsches / perlitisches Gefüge bildet. Durch das Vorsehen des zweiten Ofenbereichs lässt sich die Stahlblechbahn auf eine solche Temperatur abkühlen, wobei die Abkühlgeschwindigkeit von weniger als 25 K/sec prozesssicher eingehalten werden kann. Dabei bildet sich weiches Ferrit/Perlitgefüge, womit ein späteres Zuschneiden der Einzelplatinen im Stanzverfahren möglich wird.According to the invention, the furnace further has a second furnace region arranged behind the first furnace region in the direction of passage of the steel sheet web, the steel sheet web being able to be cooled to a temperature at a rate of less than 25 K / sec during the passage through the second furnace region, at which soft ferritic / pearlitic structure. The steel sheet web can be cooled to such a temperature by the provision of the second furnace area, the cooling rate of less than 25 K / sec being reliably maintained. This creates a soft ferrite / pearlite structure, which enables the individual blanks to be cut to size later using the stamping process.

In einer vorteilhaften Ausführungsform weist die Vorrichtung weiterhin eine Zuführungseinrichtung zum Zuführen der Stahlblechbahn zu dem Ofen und eine Abzugsvorrichtung zum Abziehen der Stahlblechbahn aus dem Ofen auf. Dabei kann von der Zuführungs- und der Abzugsvorrichtung eine Spannung auf die Stahlblechbahn aufgebracht werden, so dass sie bei im Wesentlichen waagerechter Ofenanordnung nicht zu sehr durchhängt sowie die Zugkraft die Reißfestigkeit einer Seillinie folgend nicht überschreitet.In an advantageous embodiment, the device also has a feed device for feeding the sheet steel sheet to the furnace and a removal device for pulling the sheet steel sheet out of the furnace. In this case, a tension can be applied to the steel sheet web by the feed and withdrawal devices, so that it does not sag too much when the furnace is essentially horizontal and the tensile force does not exceed the tensile strength following a rope line.

Es hat sich weiterhin als vorteilhaft erwiesen, wenn die Zuführungseinrichtung eine erste Haspel und die Abzugsvorrichtung eine zweite Haspel aufweist. Dabei kann ein Coil als übliche Lieferform von Stahlblechbändern auf die erste Haspel aufgespannt werden. Die zweite Haspel kann das vorbehandelte Stahlblechband wieder als Coil aufwickeln. Die zweite Haspel kann auch entfallen, wenn das vorbehandelte Stahlblechband sogleich weiterverarbeitet, beispielsweise einer Stanzvorrichtung zugeführt, werden soll. Um diffusible Wasserstoffbildung zu minimieren, kann der Ofen mit niedrigem Taupunkt von -70°C bis +10°C, insbesondere von circa +5°C bis +10°C betrieben werden.It has also proven to be advantageous if the feed device has a first reel and the take-off device has a second reel. A coil can be clamped onto the first reel as a standard form of delivery of sheet steel strips. The second reel can rewind the pre-treated steel strip as a coil. The second reel can also be omitted if the pretreated sheet steel strip is to be further processed immediately, for example fed to a punching device. To minimize diffusible hydrogen formation, the furnace can be operated with a low dew point from -70 ° C to + 10 ° C, in particular from approx. + 5 ° C to + 10 ° C.

Weitere Vorteile, Besonderheiten und zweckmäßige Weiterbildungen der Erfindung ergeben sich aus den Unteransprüchen und der nachfolgenden Darstellung bevorzugter Ausführungsbeispiele anhand der Abbildungen.Further advantages, special features and expedient developments of the invention result from the subclaims and the following illustration of preferred exemplary embodiments with the aid of the figures.

Von den Abbildungen zeigt:

Fig. 1
eine erfindungsgemäße Vorrichtung in Waagerechtausführung
Fig. 2
eine erfindungsgemäße Vorrichtung in Vertikalausführung
The pictures show:
Fig. 1
a device according to the invention in a horizontal design
Fig. 2
a device according to the invention in a vertical design

Fig. 1 zeigt eine erfindungsgemäße Vorrichtung in Waagerechtausführung. Die Vorrichtung weist eine erste Haspel 210 mit einem sich darauf befindlichen ersten Stahlblechcoil 310 auf. Das erste Stahlblechcoil 310 besteht aus einer aufgewickelten Al-Si-beschichteten Stahlblechbahn 300 in Bandform. Durch Drehen der ersten Haspel 210 im Uhrzeigersinn wird das Stahlband 300 abgewickelt und dem Ofen 100 zugeführt. Dabei kann eine Zuführungseinrichtung neben der ersten Haspel 210 weiterhin Führungsrollen (nicht gezeigt) aufweisen. Der Ofen 100 weist einen ersten Ofenbereich 110 auf, der auf eine Temperatur aufgeheizt ist, bei der das Al-Si der Beschichtung in die Oberfläche der Stahlblechbahn 300 eindiffundiert. Gleichzeitig diffundiert aus Eisen aus dem Stahlblechsubstrat in das Al-Si. Es entsteht eine hochschmelzende Aluminium-Silizium-Eisen-Legierung an der Oberfläche der Stahlblechbahn. Dabei geschieht die Aufheizung des Ofens über die Heizungen 150 und ein Heißluftkissen 165, das über Heißluftdüsen 160 unter der Stahlblechbahn erzeugt wird. Die Stahlblechbahn 300 schwebt auf dem Heißluftkissen 165 durch den Ofen 100, ohne diesen zu berühren. Weitere Trag- oder Führungselemente, wie beispielsweise Rollen oder dergleichen, sind nicht erforderlich. Dadurch kann keine schädigende Reaktion von aufgeschmolzenem Al-Si mit diesen Trag- und/oder Führungselementen stattfinden. Bei den Heizungen 160 handelt es sich um Gasbrenner. Es sind aber auch beispielsweise elektrische Infrarotheizungen oder Heißluftheizungen denkbar. Die Länge des ersten Ofenbereichs ist in Abhängigkeit der Durchführungsgeschwindigkeit der Stahlblechbahn 300 so bemessen, dass die Stahlblechbahn auf die Diffusionstemperatur von beispielsweise 930 °C bis 950 °C aufgeheizt wird und die erforderliche Diffusionszeit auf dieser Temperatur verbleibt. Ebenfalls ist eine eventuelle Schlussglühzeit bei der Längenbemessung des ersten Ofenbereichs 110 berücksichtigt. In Durchführungsrichtung der Stahlblechbahn folgt ein zweiter Ofenbereich 120 dem ersten Ofenbereich 110. Die Temperaturführung in dem zweiten Ofenbereich 120 und Länge des zweiten Ofenbereichs 120 sind so bemessen, dass die Stahlblechbahn mit einer Abkühlgeschwindigkeit von weniger als 25 K/sec in den Temperaturbereich von Ferrit-/Perlitgefüge abgekühlt wird, damit anschließend eine Platine aus der Stahlblechbahn ausgestanzt werden kann. Fig. 1 shows a device according to the invention in a horizontal design. The device has a first reel 210 with a first steel sheet coil 310 located thereon. The first sheet steel coil 310 consists of a wound Al-Si-coated sheet steel sheet 300 in strip form. By rotating the first reel 210 clockwise, the steel strip 300 is unwound and fed to the furnace 100. In addition to the first reel 210, a feed device can furthermore have guide rollers (not shown). The furnace 100 has a first furnace region 110, which is heated to a temperature at which the Al-Si of the coating diffuses into the surface of the steel sheet web 300. At the same time, iron diffuses from the steel sheet substrate into the Al-Si. A high-melting aluminum-silicon-iron alloy is created on the surface of the sheet steel sheet. The furnace is heated via the heaters 150 and a hot air cushion 165, which is generated via hot air nozzles 160 under the sheet steel sheet. The sheet steel sheet 300 floats on the hot air cushion 165 through the furnace 100 without touching it. Additional supporting or guiding elements, such as rollers or the like, are not required. As a result, no damaging reaction of melted Al-Si with these support and / or guide elements can take place. The heaters 160 are gas burners. However, electric infrared heaters or hot air heaters are also conceivable, for example. The length of the first furnace region is dimensioned as a function of the throughput speed of the steel sheet web 300 such that the steel sheet web is heated to the diffusion temperature of, for example, 930 ° C. to 950 ° C. and the required diffusion time remains at this temperature. Is also one Possible final glow time is taken into account when dimensioning the length of the first furnace area 110. A second furnace region 120 follows the first furnace region 110 in the direction of passage of the steel sheet web. The temperature control in the second furnace region 120 and the length of the second furnace region 120 are dimensioned such that the steel sheet web reaches the temperature range of ferrite with a cooling rate of less than 25 K / sec. / Perlite structure is cooled so that a board can then be punched out of the sheet steel sheet.

An den zweiten Ofenbereich 120 schließt sich eine Abzugsvorrichtung mit einer zweiten Haspel 220 an. Die zweiten Haspel 220 dreht sich ebenfalls im Uhrzeigersinn, wodurch die vorbehandelte Stahlblechbahn wieder zu einem zweiten Coil 320 aufgewickelt wird. Eine Abzugsvorrichtung kann neben der zweiten Haspel 220 weiterhin Führungsrollen (nicht gezeigt) aufweisen.An extraction device with a second reel 220 is connected to the second furnace region 120. The second reel 220 also rotates clockwise, as a result of which the pretreated sheet steel web is rewound into a second coil 320. In addition to the second reel 220, a pull-off device can also have guide rollers (not shown).

Fig. 2 zeigt eine erfindungsgemäße Vorrichtung in Vertikalausführung. Der Ofen 100 ist als Turm in im Wesentlichen vertikaler Richtung ausgeführt. Die Stahlblechbahn 300 wird von oben nach unten durch den Ofen 100 hindurchgeführt. Durch die vertikale Bauweise sind keine Maßnahmen wie das Vorsehen von Heißluftkissen oder Seilzugvorrichtungen erforderlich, um die Stahlblechbahn berührungslos durch den Ofen 100 hindurch zu führen. Die Durchführungsrichtung von oben nach unten erleichtert die Temperaturführung im Ofen, da sich der kühlere zweite Ofenbereich 120 unterhalb des auf Diffusionstemperatur aufgeheizten ersten Ofenbereichs 110 befindet. Da ein Heißluftkissen 165 nicht benötigt wird, sind zur homogenen Aufheizung beider Oberflächen des Stahlblechbands 300 auf beiden Seiten des Ofens 100 Heizungen 150 vorgesehen. Diese können wie im Fall der waagerechten Anordnung beispielsweise als Gasbrenner oder als Heißluftheizungen oder beispielsweise elektrische Strahlungsheizungen ausgeführt werden. Fig. 2 shows a device according to the invention in a vertical design. The furnace 100 is designed as a tower in a substantially vertical direction. The sheet steel sheet 300 is passed through the furnace 100 from top to bottom. Due to the vertical construction, no measures such as the provision of hot air cushions or cable pulling devices are necessary in order to guide the steel sheet web through the furnace 100 without contact. The direction of passage from top to bottom facilitates temperature control in the furnace, since the cooler second furnace region 120 is located below the first furnace region 110 heated to the diffusion temperature. Since a hot air cushion 165 is not required, 100 heaters 150 are provided on both sides of the furnace for homogeneous heating of both surfaces of the steel sheet strip 300. As in the case of the horizontal arrangement, these can be designed, for example, as gas burners or as hot air heaters or, for example, electric radiant heaters.

Zuführungs- und Abzugseinrichtung für das Stahlblechband 300 sind analog der waagerechten Ausführungsform aufgebaut.Feeding and withdrawing device for the steel strip 300 are constructed analogously to the horizontal embodiment.

Die hier gezeigten Ausführungsformen stellen nur Beispiele für die vorliegende Erfindung dar und dürfen daher nicht einschränkend verstanden werden.The embodiments shown here are only examples of the present invention and should therefore not be understood as restrictive.

Bezugszeichenliste:Reference symbol list:

100100
Ofenoven
110110
erster Ofenbereichfirst furnace area
120120
zweiter Ofenbereichsecond furnace area
150150
Heizungheater
160160
HeißluftdüseHot air nozzle
165165
HeißluftkissenHot air cushion
210210
erste Haspelfirst reel
220220
zweite Haspelsecond reel
300300
StahlblechbahnSheet steel sheet
310310
erstes Stahlblechcoilfirst sheet steel coil
320320
zweites Stahlblechcoilsecond sheet steel coil

Claims (15)

  1. Method for diffusing Al-Si into a surface of a sheet steel web (300) coated with Al-Si, it being possible to produce a sheet steel component, hot-stamped in a press-hardening process, from the treated sheet steel web (300),
    characterized by the steps of
    a. introducing the sheet steel web (300) into a furnace (100) which can be heated to a diffusion temperature of 930 °C to 950 °C;
    b. contactlessly conveying the sheet steel web (300) coated with Al-Si through the furnace (100), which has been heated to the diffusion temperature, thereby heating the sheet steel web (300) to the diffusion temperature and diffusing the Al-Si into a surface of the sheet steel web (300);
    c. cooling the sheet steel web (300), which has Al-Si diffused into a surface, to below martensite formation temperature at a rate of less than approximately 25 K/sec.
  2. Method according to claim 1,
    characterized in that
    the sheet steel web (300) is coated on both sides with Al-Si and Al-Si is diffused into both surfaces.
  3. Method according to either claim 1 or claim 2,
    characterized in that
    the sheet steel web (300) is taken from a first sheet steel coil (310).
  4. Method according to any of the preceding claims,
    characterized in that,
    after being conveyed through the furnace (100) and cooled to the temperature range of a ferrite/pearlite structure, the sheet steel web (300) is wound into a second sheet steel coil (320).
  5. Method according to any of the preceding claims,
    characterized in that
    the sheet steel web (300) is heated to the diffusion temperature in a first furnace portion (110) and, after the Al-Si is diffused into a surface of the sheet steel web (300), is cooled in a second furnace portion (120) of the same furnace to the temperature range of a ferrite/pearlite structure at a cooling rate of less than 25 K/sec.
  6. Method according to any of the preceding claims,
    characterized in that
    the sheet steel web (300) is conveyed contactlessly through the furnace (100) on a cushion (165) of hot air.
  7. Method according to any of the preceding claims,
    characterized in that
    the sheet steel web (300) is conveyed through the furnace (100) by the application of a tractive force.
  8. Method according to any of the preceding claims,
    characterized in that
    the furnace (100) is arranged substantially vertically and the sheet steel web (300) is conveyed through the furnace (100) from the top to the bottom.
  9. Device for diffusing Al-Si into a surface of a sheet steel web (300) coated with Al-Si, it being possible for a sheet steel plate, which can be shaped and hardened in a press hardening process, to be produced from the treated sheet steel web (300), the device comprising a furnace (100), the furnace (100) comprising a first region (110) which can be heated to a diffusion temperature, it being possible for the sheet steel web (300) coated with Al-Si to be conveyed contactlessly through the furnace (100), the furnace (100) also having a second furnace region (120) arranged downstream of the first furnace region (110) in the conveying direction of the sheet steel web (300),
    characterized in that
    the length of the second furnace region (120), in conjunction with the temperature control in this region, is such that, while being conveyed through the second furnace region (120), the sheet steel web (100) can be cooled to the temperature range of a ferrite/pearlite structure at a rate of less than 25 K/sec.
  10. Device according to claim 9,
    characterized in that
    the furnace (100) has a device for producing a cushion (165) of hot air on which the sheet steel web (300) can be conveyed contactlessly through the furnace (100).
  11. Device according to claim 10,
    characterized in that
    the furnace (100) has a hot air nozzle (160) for producing a cushion (165) of hot air.
  12. Device according to any of claims 9 to 11,
    characterized in that
    the furnace (100) has a device for applying a tractive force to the sheet steel web (300) for conveying the sheet steel web (300) contactlessly through the furnace (100).
  13. Device according to any of claims 9 to 12,
    characterized in that
    the furnace (100) is arranged substantially vertically, it being possible for the sheet steel web (300) coated with Al-Si to be contactlessly conveyed therethrough from the top to the bottom.
  14. Device according to any of claims 9 to 13,
    characterized in that
    the device further comprises a feeding means for feeding the sheet steel web (300) to the furnace (100) and a withdrawal device (220) for withdrawing the sheet steel web (300) from the furnace (100).
  15. Device according to claim 14,
    characterized in that
    the feeding means has a first reel (210) and the withdrawal device (220) has a second reel (220).
EP14733592.1A 2013-06-25 2014-06-23 Diffusion of aluminium-silicon into a steel sheet web Active EP3013994B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP14733592.1A EP3013994B1 (en) 2013-06-25 2014-06-23 Diffusion of aluminium-silicon into a steel sheet web

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP13173619.1A EP2818571B1 (en) 2013-06-25 2013-06-25 Diffusion of aluminium-silicon into a steel sheet web
PCT/EP2014/063150 WO2014206933A1 (en) 2013-06-25 2014-06-23 Inward diffusion of aluminium-silicon into a steel sheet
EP14733592.1A EP3013994B1 (en) 2013-06-25 2014-06-23 Diffusion of aluminium-silicon into a steel sheet web

Publications (2)

Publication Number Publication Date
EP3013994A1 EP3013994A1 (en) 2016-05-04
EP3013994B1 true EP3013994B1 (en) 2020-03-04

Family

ID=48672476

Family Applications (2)

Application Number Title Priority Date Filing Date
EP13173619.1A Active EP2818571B1 (en) 2013-06-25 2013-06-25 Diffusion of aluminium-silicon into a steel sheet web
EP14733592.1A Active EP3013994B1 (en) 2013-06-25 2014-06-23 Diffusion of aluminium-silicon into a steel sheet web

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP13173619.1A Active EP2818571B1 (en) 2013-06-25 2013-06-25 Diffusion of aluminium-silicon into a steel sheet web

Country Status (9)

Country Link
US (1) US20160145733A1 (en)
EP (2) EP2818571B1 (en)
JP (1) JP6583638B2 (en)
KR (1) KR20160058746A (en)
CN (1) CN105518177A (en)
BR (1) BR112015032358B1 (en)
CA (1) CA2915440A1 (en)
MX (1) MX2015017681A (en)
WO (1) WO2014206933A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104878188B (en) * 2015-05-20 2017-02-22 东北大学 Experimental facility and experiment method for realizing air cushion type heat treatment of aluminum strips
KR101858863B1 (en) 2016-12-23 2018-05-17 주식회사 포스코 Hot dip aluminum alloy plated steel material having excellent corrosion resistance and workability
EP3589772B1 (en) 2017-02-28 2023-04-05 Tata Steel IJmuiden B.V. Method for producing a hot-formed coated steel product
CN109764674B (en) * 2019-01-27 2021-01-05 安徽华淮澄膜科技有限公司 High-temperature tunnel furnace for sintering and forming powder material

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58120733A (en) * 1982-01-09 1983-07-18 Nippon Steel Corp Continuous annealing method of electromagnetic steel plate
US5096478A (en) * 1991-03-26 1992-03-17 Glasstech, Inc. Apparatus and method for conveying glass sheets
GB9210683D0 (en) * 1992-05-19 1992-07-08 Rolls Royce Plc Multiplex aluminide-silicide coating
JPH0610063A (en) * 1992-06-24 1994-01-18 Nippon Steel Corp Heat treating furnace for steel strip
US5650235A (en) * 1994-02-28 1997-07-22 Sermatech International, Inc. Platinum enriched, silicon-modified corrosion resistant aluminide coating
CN1168418A (en) * 1997-04-28 1997-12-24 张光渊 Nickel-less stable steel for industrial furnace
DE10045479A1 (en) * 2000-09-14 2002-04-04 Schott Glas Method and device for contactless storage and transportation of flat glass
JP4990449B2 (en) * 2001-07-27 2012-08-01 新日本製鐵株式会社 Aluminum-coated steel sheet for high-strength automotive parts and automotive parts using the same
DE10208216C1 (en) * 2002-02-26 2003-03-27 Benteler Automobiltechnik Gmbh Production of a hardened metallic component used as vehicle component comprises heating a plate or a pre-molded component to an austenitizing temperature, and feeding via a transport path while quenching parts of plate or component
DE10303228B3 (en) * 2003-01-28 2004-04-15 Kramer, Carl, Prof. Dr.-Ing. Device for heat treating metallic strips has a heat treatment section containing a heating region and a first cooling region, and nozzle fields for producing impact beams onto the strips
JP4860542B2 (en) * 2006-04-25 2012-01-25 新日本製鐵株式会社 High strength automobile parts and hot pressing method thereof
DE102007057855B3 (en) * 2007-11-29 2008-10-30 Benteler Automobiltechnik Gmbh Production of moldings with structure zones of different ductility comprises heat treatment of aluminum-silicon coated high-tensile steel blank, followed by treating zones at different temperature
JP5098864B2 (en) * 2008-07-11 2012-12-12 新日鐵住金株式会社 High strength automotive parts with excellent post-painting corrosion resistance and plated steel sheets for hot pressing
KR101008042B1 (en) * 2009-01-09 2011-01-13 주식회사 포스코 Aluminum Coated Steel Sheet with Excellent Corrosion Resistance and Hot Press Formed Article Using The Same and Manufacturing Method Thereof
JP5463906B2 (en) * 2009-12-28 2014-04-09 新日鐵住金株式会社 Steel sheet for hot stamping and manufacturing method thereof
US9677145B2 (en) * 2011-08-12 2017-06-13 GM Global Technology Operations LLC Pre-diffused Al—Si coatings for use in rapid induction heating of press-hardened steel

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Also Published As

Publication number Publication date
US20160145733A1 (en) 2016-05-26
BR112015032358B1 (en) 2020-09-24
EP2818571A1 (en) 2014-12-31
KR20160058746A (en) 2016-05-25
JP6583638B2 (en) 2019-10-02
WO2014206933A1 (en) 2014-12-31
BR112015032358A2 (en) 2017-07-25
EP3013994A1 (en) 2016-05-04
MX2015017681A (en) 2016-06-14
CA2915440A1 (en) 2014-12-31
EP2818571B1 (en) 2017-02-08
JP2016529386A (en) 2016-09-23
CN105518177A (en) 2016-04-20

Similar Documents

Publication Publication Date Title
EP2497840B2 (en) Oven system for partially heating steel blanks
EP2227570B1 (en) Method for producing a shaped component comprising at least two joining areas having different ductility
DE102011053698C5 (en) Process for the manufacture of structural and chassis components by thermoforming and heating station
EP2456896A1 (en) Method and device for energy-efficient hot forming
EP2044234B1 (en) Method for flexibly rolling coated steel strips
EP2905346B1 (en) Heat treatment process
DE102011056444B3 (en) Method and device for partial hardening of sheet metal components
EP3013994B1 (en) Diffusion of aluminium-silicon into a steel sheet web
DE102017110864B3 (en) Method and device for producing hardened sheet steel components with different sheet thicknesses
DE102016100648B4 (en) A heat treatment furnace and method for heat treating a precoated sheet steel plate and method of making a motor vehicle component
EP2570503A2 (en) Method and device for heating a pre-coated steel circuit board
EP3408417A1 (en) Heat treatment method and heat treatment device
WO2017129602A1 (en) Heat treatment method and heat treatment device
WO2017025460A1 (en) Method for heat treatment of a sheet steel component and heat treatment apparatus therefor
EP3159419B1 (en) Method of fabrication of roll formed partly hardened profiles
AT509597B1 (en) METHOD AND DEVICE FOR PRODUCING A SHAPE COMPONENT
EP3420111B1 (en) Process for targeted heat treatment of individual component zones
WO2017137259A1 (en) Heat treatment method and heat treatment device
EP3184655A1 (en) Heat treatment furnace and method for the heat treatment of a precoated steel sheet board and method for manufacturing a motor vehicle part
DE102016109095B4 (en) Apparatus and method for partial hardening of sheet steel components
EP3201369B1 (en) Method for the manufacture of steel strip material having different mechanical properties across the width of the strip
DE102020200808A1 (en) Method for producing a sheet metal component hardened at least partially from steel and an at least partially hardened sheet metal component made from 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: 20160125

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent

Extension state: BA ME

DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20180205

REG Reference to a national code

Ref country code: DE

Ref legal event code: R079

Ref document number: 502014013752

Country of ref document: DE

Free format text: PREVIOUS MAIN CLASS: C23C0010280000

Ipc: C21D0009460000

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

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

Free format text: STATUS: GRANT OF PATENT IS INTENDED

RIC1 Information provided on ipc code assigned before grant

Ipc: C21D 9/573 20060101ALI20190813BHEP

Ipc: C21D 1/673 20060101ALI20190813BHEP

Ipc: F27B 1/00 20060101ALI20190813BHEP

Ipc: C23C 10/52 20060101ALI20190813BHEP

Ipc: C23C 10/02 20060101ALI20190813BHEP

Ipc: F27B 9/39 20060101ALI20190813BHEP

Ipc: F27B 9/02 20060101ALI20190813BHEP

Ipc: C23C 10/28 20060101ALI20190813BHEP

Ipc: C23C 10/60 20060101ALI20190813BHEP

Ipc: F27B 1/20 20060101ALI20190813BHEP

Ipc: C21D 9/63 20060101ALI20190813BHEP

Ipc: F27B 9/10 20060101ALI20190813BHEP

Ipc: F27D 3/00 20060101ALI20190813BHEP

Ipc: F27B 9/28 20060101ALI20190813BHEP

Ipc: C21D 9/46 20060101AFI20190813BHEP

Ipc: F27B 9/38 20060101ALI20190813BHEP

INTG Intention to grant announced

Effective date: 20190916

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

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

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1240414

Country of ref document: AT

Kind code of ref document: T

Effective date: 20200315

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 502014013752

Country of ref document: DE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: LANGUAGE OF EP DOCUMENT: GERMAN

REG Reference to a national code

Ref country code: NL

Ref legal event code: FP

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

Ref country code: FI

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: 20200304

Ref country code: NO

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: 20200604

Ref country code: RS

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: 20200304

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

Ref country code: BG

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: 20200604

Ref country code: GR

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: 20200605

Ref country code: LV

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: 20200304

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: 20200304

Ref country code: HR

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: 20200304

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

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

Ref country code: LT

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: 20200304

Ref country code: ES

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: 20200304

Ref country code: CZ

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: 20200304

Ref country code: IS

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: 20200704

Ref country code: RO

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: 20200304

Ref country code: SK

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: 20200304

Ref country code: EE

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: 20200304

Ref country code: SM

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: 20200304

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: 20200729

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 502014013752

Country of ref document: DE

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

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

Ref country code: IT

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: 20200304

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: 20200304

Ref country code: MC

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: 20200304

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

26N No opposition filed

Effective date: 20201207

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

Ref country code: SI

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: 20200304

Ref country code: PL

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: 20200304

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: 20200623

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20200630

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: 20200623

Ref country code: LI

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

Effective date: 20200630

Ref country code: CH

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

Effective date: 20200630

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

Ref country code: BE

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

Effective date: 20200630

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

Ref country code: GB

Payment date: 20210625

Year of fee payment: 8

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

Ref country code: TR

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: 20200304

Ref country code: MT

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: 20200304

Ref country code: CY

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: 20200304

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

Ref country code: MK

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: 20200304

Ref country code: AL

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: 20200304

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20220623

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 NON-PAYMENT OF DUE FEES

Effective date: 20220623

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

Ref country code: NL

Payment date: 20230620

Year of fee payment: 10

Ref country code: FR

Payment date: 20230628

Year of fee payment: 10

Ref country code: DE

Payment date: 20230620

Year of fee payment: 10

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

Ref country code: AT

Payment date: 20230621

Year of fee payment: 10