EP1319091A1 - Method for producing a steel strip or sheet consisting predominantly of mn-austenite - Google Patents

Method for producing a steel strip or sheet consisting predominantly of mn-austenite

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Publication number
EP1319091A1
EP1319091A1 EP01978372A EP01978372A EP1319091A1 EP 1319091 A1 EP1319091 A1 EP 1319091A1 EP 01978372 A EP01978372 A EP 01978372A EP 01978372 A EP01978372 A EP 01978372A EP 1319091 A1 EP1319091 A1 EP 1319091A1
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EP
European Patent Office
Prior art keywords
max
steel
strip
casting
thin strip
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP01978372A
Other languages
German (de)
French (fr)
Other versions
EP1319091B1 (en
Inventor
Gabriele BRÜCKNER
Wolfgang Schlump
Hans-Joachim Krautschick
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.)
Outokumpu Nirosta GmbH
Original Assignee
ThyssenKrupp Nirosta GmbH
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Publication of EP1319091A1 publication Critical patent/EP1319091A1/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
    • B22D11/0622—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by two casting wheels
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/021—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips involving a particular fabrication or treatment of ingot or slab
    • C21D8/0215—Rapid solidification; Thin strip casting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys

Definitions

  • the invention relates to a method for producing a steel strip or sheet consisting predominantly of Mn austenite.
  • Steels that are suitable for the manufacture of such products are assigned to the AISI 200 and have the designation S20100 to S24000.
  • Steel materials of this type are characterized by high strength, which is retained even after welding in the area of the weld.
  • a further increase in the strength of steels of the conventionally castable steels explained above can be achieved by alloying aluminum and / or silicon. These two elements support mixed crystal hardening and thus lead to a further increase in strength.
  • the addition of aluminum and silicon can influence the stacking error energy, which in turn has an influence on the deformation processes.
  • the addition of aluminum leads to an increase in the stack error energy and favors the deformation due to the formation of twins.
  • silicon lowers the stack fault energy, but favors the deformation about martensite formation.
  • the combined addition of silicon and aluminum can thus have a targeted influence on the hardening of the material during deformation.
  • the formation of martensite leads to a firm consolidation, while the formation of twins reduces the consolidation.
  • the object of the invention is to provide a method for producing a steel consisting predominantly of Mn austenite, which can be produced cost-effectively and at the same time has increased strength compared to the prior art.
  • This object is achieved by a method for producing a steel strip or sheet consisting predominantly of Mn austenite, in which a steel is melted which contains (in% by weight) the following alloy components: 15.00 - 24.00 Cr,
  • the steel in a casting gap formed between two rotating rolls or rollers to form a thin strip with a thickness of max. 10 mm is poured, the rollers or rollers being cooled so strongly that the thin strip cools in the casting gap at a cooling rate of at least 200 K / s.
  • the thickness of the thin strip is preferably between 1 and 5 mm.
  • the specification of the steel composition used according to the invention also includes those alloys in which the content of those alloy elements is zero, for which only a maximum permissible upper limit of the content is specified.
  • the chromium content of the steel can be 17.00-21.00% by weight of Cr, the manganese content can be 8.00-12.00% by weight of Mn and / or the nitrogen content limited to 0.40-0.60 wt% N his.
  • levels of Ni, Mo and / or Cu may be present in the steel.
  • the contents of the alloy elements contained in the steel composition used according to the invention are each optimized with regard to the effect of these elements.
  • Cr, Mn, Mo, V, Nb and Al increase the nitrogen solubility in the melt, while Ni, Cu as austenite formers and Si reduce the nitrogen solubility.
  • Si also acts as a mixed crystal hardener. It is also used for grain refinement and lowers the stacking error energy.
  • AI increases the stack fault energy.
  • Mo also acts as a mixed crystal hardener and improves the corrosion behavior.
  • V also has a grain-refining effect and increases strength.
  • the addition of Nb leads to an increase in strength through precipitation hardening.
  • the invention makes use of the basically known technology of a strip caster by casting the steel in the casting gap formed between the rolls or rolls, for example a double-roll casting apparatus ("double roller"), and thereby cooling it so much that it causes a displacement of primarily ferritic solidification comes towards primary austenitic solidification.
  • double roller double-roll casting apparatus
  • This makes it possible to transfer the nitrogen dissolved in the melt into the steel, because the austenite has a high solubility for nitrogen.
  • the possibility of such intensive cooling is only opened by casting a thin strip in a casting nip, the walls of which are formed by the casting rolls or rollers moving at essentially the same speed as the cast strip, so that a constant, intensive heat exchange between the walls (casting rollers / rollers) and the cast steel in the casting gap is guaranteed.
  • the intensive cooling which takes place at a high cooling rate, ensures that nitrogen gas bubbles which may form in the solidifying melt remain small and the pressure directed against them is high. This prevents outgassing of the nitrogen during the solidification.
  • such leakage of nitrogen is suppressed by the high ferrostatic pressure which occurs due to the large height of the melt pool in the casting gap. In this way it is ensured that the pressure P N in the nitrogen gas bubbles which may arise is always lower than the sum of the ambient pressure P A , the ferrostatic pressure P F and twice the surface tension ⁇ of the gas bubbles in relation to the bubble radius r (ie P N ⁇ P A + P F + 2 ⁇ / r).
  • Hot strip made of continuously cast alloy can currently only be produced on a conventional hot strip mill with a thickness of at least 3.5 mm.
  • the production of cold strip in the typical target thicknesses of 0.8 - 1.2 mm can only be achieved by intermediate annealing.
  • intermediate annealing is no longer necessary due to the smaller thickness of the hot strip obtained.
  • the procedure according to the invention makes it possible to produce steel strips and sheets which have particularly high nitrogen contents of 0.4 to 0.6% by weight and to which up to 3% of aluminum and / or silicon are alloyed at the same time, without the steel production having to do so must be carried out under excess pressure or particularly high levels of manganese are required.
  • the steel products produced in this way have a fine-grained, isotropic structure with a small macro-segregation or a small number of coarse inclusions. Due to its Al and / or Si content, they also have increased strength and ductility compared to the prior art.
  • the hardening and thus the energy absorption in the event of deformation can also be set in a targeted manner by the choice of alloy.
  • the thin strip is preferably cast under a protective gas atmosphere.
  • a thin strip with a modified surface can be produced in a simple manner, the degree of oxidation of which can be influenced in a targeted manner. In this way, scaling can be avoided.
  • the strip obtained in this way can then be hot-rolled "inline" in a roll stand without the risk of the rollers sticking together.
  • it is particularly advantageous if the thin strip is heated to an initial rolling temperature before hot rolling. This increase in temperature enables higher degrees of forming to be achieved during hot rolling.
  • the hot strip By subjecting the hot strip to a heat treatment after hot rolling, its structure can be specifically optimized.
  • the heat treatment can include annealing and subsequent controlled cooling.
  • steel sheets produced according to the invention are particularly suitable for the production of body sheet metal parts, of stiffening structural components used in particular in general vehicle construction and especially in automobile construction, of chassis parts, of vehicle wheels and of fuel tanks.
  • the particularly good strength properties of steel sheets produced by the method according to the invention have an advantageous effect.
  • the good corrosion resistance of steel sheets and strips according to the invention proves to be advantageous in those applications in which they come into contact with aggressive media, such as fuels. The invention is explained in more detail below on the basis of a drawing illustrating an exemplary embodiment.
  • the single figure shows schematically a strip casting installation 1.
  • a steel is processed which, in addition to the usual unavoidable impurities (in% by weight), contains 0.08% C, 0.5% Si, 10% Mn, 19% Cr, 0.5% N , 0.3% AI and the rest contains iron.
  • the strip caster 1 comprises a “double roller” two-roll casting apparatus, of which the rolls 2, 3, which rotate in opposite directions about an axis of rotation, are shown in the figure.
  • a casting gap 4 is formed between the rollers 2, 3 and is continuously filled with melt, so that a melt pool S is formed above the casting gap 4.
  • the rollers 2, 3 are intensively cooled during the casting process, so that the melt entering the casting gap 4 primarily solidifies austenitically at cooling rates of more than 200 K / s and the casting gap 4 as thin strip D with a thickness of 1 to 5 mm leaves.
  • the thin strip D produced in this way then passes through a furnace 5, in which it is heated to an initial rolling temperature.
  • Both the two-roll casting device with the rolls 2, 3 and the furnace 5 are accommodated in a housing 6 in which a protective gas atmosphere is contained.
  • a protective gas atmosphere is contained.
  • the thin strip D heated to the initial rolling temperature enters a rolling mill 7, in which it is hot-rolled to a final dimension. Due to the high initial rolling temperature, large degrees of forming are possible.
  • the hot strip W rolled out of the thin strip D, which reaches the rolling mill essentially without scale, has a particularly high-quality surface after hot rolling.
  • the hot strip W is annealed in a continuous annealing furnace 8 and then cooled in a controlled manner under a cooling device 9 in order to specifically improve its structure.
  • the hot strip W heat-treated in this way is finally wound into a reel 10.
  • Steel strip produced in the manner explained above has particularly high strength compared to conventionally assembled and produced steel strips due to its high nitrogen content achieved by the rapid cooling between the rolls 2, 3 of the two-roll casting apparatus, and at the same time good deformability and good energy absorption capacity.
  • the table below compares the superior strength values of the hot strip W produced according to the invention in the casting and rolling mill 1 with the strength values of Mn austenite steels conventionally produced by continuous casting.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Continuous Casting (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Metal Rolling (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

The method according to the invention can be used for the economic manufacture of a steel strip (W) or sheet consisting mainly of Mn-austenite which possesses enhanced strength compared with the prior art. For this purpose a steel is melted which contains at least the following alloying components (in wt. %), 15.00-24.00% Cr, 5.00-12.00% Mn, 0.10-0.60% N, 0.01-0.2% C, max. 3.00% Al and/or Si, max. 0.07% P, max. 0.05% S, max. 0.5% Nb, max. 0.5% V, max. 3.0% Ni, max. 5.0% Mo, max. 2.0% Cu as well as iron and unavoidable impurities as the remainder. This steel is cast into a thin strip (D) having a maximum thickness of 10 mm in a casting gap formed between two rotating rollers (2, 3) or rolls. The rollers (2, 3) or rolls are cooled so intensively that the thin strip (D) in the casting gap (4) is cooled at a cooling rate of at least 200 K/s.

Description

Verfahren zum Herstellen eines überwiegend aus Mn- Austenit bestehenden Stahlbands oder -blechs Process for producing a steel strip or sheet consisting predominantly of Mn austenite
Die Erfindung betrifft ein Verfahren zum Herstellen eines überwiegend aus Mn-Austenit bestehenden Stahlbands oder -blechs. Stähle, die zur Herstellung derartiger Produkte geeignet sind, werden der AISI 200 zugeordnet und tragen dort die Bezeichnung S20100 bis S24000. Stahlwerkstoffe dieser Art zeichnen sich durch eine hohe Festigkeit aus, die nach einem Verschweißen auch im Bereich der Schweißnaht erhalten bleibt.The invention relates to a method for producing a steel strip or sheet consisting predominantly of Mn austenite. Steels that are suitable for the manufacture of such products are assigned to the AISI 200 and have the designation S20100 to S24000. Steel materials of this type are characterized by high strength, which is retained even after welding in the area of the weld.
Diese guten Festigkeitseigenschaften werden durch interstitelle und substitutionelle Mischkristallhärtung erreicht. Besonders wirksam sind diesbezüglich Kohlenstoff und Stickstoff. Höhere Kohlenstoff-Gehalte werden allerdings wegen der unerwünschten Karbidbildung vermieden. Daher wird bevorzugt Stickstoff zur interstitiellen Mischkristallhärtung in Stählen der in Rede stehenden Art eingesetzt. Die Erzeugung von Stählen mit erhöhtem Stickstoff-Gehalt ist allerdings in Bezug auf die Legierungsbestandteile oder die zur Erzeugung benötigten Apparaturen aufwendig.These good strength properties are achieved through interstitial and substitutional mixed crystal hardening. Carbon and nitrogen are particularly effective in this regard. However, higher carbon contents are avoided due to the undesirable carbide formation. Therefore, nitrogen is preferably used for interstitial mixed crystal hardening in steels of the type in question. The production of steels with an increased nitrogen content is, however, complex in relation to the alloy components or the equipment required for the production.
Bei einem bekannten Verfahren zur Erzeugung von Stählen mit höheren Stickstoff-Gehalten wird die Schmelze unter Druckbeaufschlagtang erschmolzen. Der auf der Schmelze lastende Druck liegt dabei so weit über dem Partialdruck des Stickstoffs, daß der Stickstoff in dem jeweiligen Stahl in Lösung geht. Der Vorteil dieser Vorgehensweise besteht darin, daß Stähle mit höheren Stickstoffgehalten ohne die Zugabe von besonderen Mengen anderer Legierungselemente hergestellt werden können/' Nachteilig ist jedoch der dazu erforderliche hohe apparative Aufwand.In a known method for the production of steels with higher nitrogen contents, the melt is melted under pressure. The pressure on the melt is so far above the partial pressure of nitrogen that the nitrogen in the respective Steel goes into solution. The advantage of this approach is that steel can be produced with higher nitrogen content without the addition of specific amounts of other alloying elements / 'However, the disadvantage is the high cost of equipment required for this purpose.
Ein alternatives Vorgehen zum Inlösungbringen des Stickstoffs durch eine Druckbeaufschlagung beim Erschmelzen besteht darin, die Löslichkeit der Schmelze selbst zu erhöhen. Dies kann durch hohe Gehalte an Chrom und Mangan- erreicht werden. Eine von M. du Toit erstellte Beschreibung der Eigenschaften von entsprechend zusammengesetzten Stählen findet sich derzeit im Internet unter der Adresse "www.tecnet.co.za/mags/steel/ featurel.htm". Die bekannten Stähle lassen sich ohne eine Druckbeaufschlagung erschmelzen und konventionell vergießen, nicht jedoch im Strangguß. Der Verguß der bekannten Stähle bringt daher hohe Kosten mit sich.An alternative approach to dissolving the nitrogen by pressurizing it during melting is to increase the solubility of the melt itself. This can be achieved by high levels of chromium and manganese. A description of the properties of appropriately composed steels created by M. du Toit is currently available on the Internet at "www.tecnet.co.za/mags/steel/ featurel.htm". The known steels can be melted without conventional pressure and cast conventionally, but not in continuous casting. Casting the known steels therefore involves high costs.
Eine weitere Erhöhung der Festigkeit von Stählen der voranstehend erläuterten, konventionell vergießbaren Stähle kann durch Zulegieren von Aluminium und / oder Silizium erreicht werden. Diese beiden Elemente unterstützen die Mischkristallhärtung und führen so zu einer weiteren Steigerung der Festigkeit. Außerdem läßt sich durch die Zugabe von Aluminium und Silizium die Stapelfehlerenergie beeinflußen, welche wiederum Einfluß auf die Verformungsvorgänge hat. So führt die Zugabe von Aluminium zu einer Erhöhung der Stapelfehlerenergie und begünstigt die Verformung durch Zwillingsbildung. Silizium dagegen senkt demgegenüber die Stapelfehlerenergie, begünstigt jedoch die Verformung über Martensitbildung. Durch die kombinierte Zugabe von Silizium und Aluminium kann somit gezielt Einfluß auf die Verfestigung des Werkstoffs bei Verformung genommen werden. Die Bildung von Martensit führt zu einer hofien Verfestigung, während durch Zwillingsbildung die Verfestigung herabgesetzt wird.A further increase in the strength of steels of the conventionally castable steels explained above can be achieved by alloying aluminum and / or silicon. These two elements support mixed crystal hardening and thus lead to a further increase in strength. In addition, the addition of aluminum and silicon can influence the stacking error energy, which in turn has an influence on the deformation processes. The addition of aluminum leads to an increase in the stack error energy and favors the deformation due to the formation of twins. In contrast, silicon lowers the stack fault energy, but favors the deformation about martensite formation. The combined addition of silicon and aluminum can thus have a targeted influence on the hardening of the material during deformation. The formation of martensite leads to a firm consolidation, while the formation of twins reduces the consolidation.
Den Vorzügen der Zugabe von Gehalten an Aluminium und Silizium zu Stählen der in Rede stehenden Art steht der Nachteil gegenüber, daß sie Ferritbildner sind und die primäre ferritische Erstarrung begünstigen. Der entstehende Ferrit hat nur eine geringe Löslichkeit für Stickstoff. Letzterer wird infolgedessen bei der Erstarrung in Form von Gasblasen ausgeschieden. Um dennoch einen austenitischen Stahl von hoher Festigkeit unter Beibehaltung des erhöhten Stickstoff-Gehaltes zu erreichen, müßte daher der Austenit stabilisiert werden. Die dazu erforderlichen weiter erhöhten Gehalte an Mangan führen jedoch neben einer Erhöhung der Rohstoffkosten zu erheblichen Problemen bei der Erzeugung derart hoch manganhaltiger Stähle im Stahlwerk.The advantages of adding aluminum and silicon contents to steels of the type in question are offset by the disadvantage that they are ferrite formers and favor the primary ferritic solidification. The resulting ferrite has only a low solubility for nitrogen. The latter is consequently eliminated in the form of gas bubbles during solidification. In order to nevertheless achieve an austenitic steel of high strength while maintaining the increased nitrogen content, the austenite would have to be stabilized. However, the further increases in manganese required for this, in addition to an increase in raw material costs, lead to considerable problems in the production of such high-manganese steels in the steel mill.
Die Aufgabe der Erfindung besteht darin, ein Verfahren zum Herstellen eines überwiegend aus Mn-Austenit bestehenden Stahls zu schaffen, der sich kostengerecht herstellen läßt und gleichzeitig eine gegenüber dem Stand der Technik erhöhte Festigkeit besitzt.The object of the invention is to provide a method for producing a steel consisting predominantly of Mn austenite, which can be produced cost-effectively and at the same time has increased strength compared to the prior art.
Diese Aufgabe wird durch ein Verfahren zum Herstellen eines überwiegend aus Mn-Austenit bestehenden Stahlbands oder -blechs gelöst, bei dem ein Stahl erschmolzen wird, welcher (in Gew.-%) die folgenden Legierungsbestandteile enthält : 15,00 - 24,00 Cr,This object is achieved by a method for producing a steel strip or sheet consisting predominantly of Mn austenite, in which a steel is melted which contains (in% by weight) the following alloy components: 15.00 - 24.00 Cr,
5,00 - 12,00 % n,5.00 - 12.00% n,
0,10 - 0,60 Ό N,0.10 - 0.60 Ό N,
0,01 - 0,2 Ό c, max. 3,00 , Ό AI und / oder Si, max. 0,07 g.0.01 - 0.2 Ό c, max. 3.00, Ό AI and / or Si, max. 0.07 g.
Ό P, max. 0,05 g. Ό s, max . 0,5 Q. Ό Nb, max. 0,5 Q,Ό P, max. 0.05 g. Ό s, max. 0.5 Q. Ό Nb, max. 0.5 Q,
"o v, max. 3,0 g. Ό Ni, max. 5,0 Q. Ό Mo, max. 2,0 g. "o Cu sowie als Re:st Eisen ιund unvermeidbare Verunreinigungen,"o v, max. 3.0 g. Ό Ni, max. 5.0 Q. Ό Mo, max. 2.0 g." o Cu as well as Re: st iron ι and unavoidable impurities,
und bei dem der Stahl in einem zwischen zwei rotierenden Walzen oder Rollen gebildeten Gießspalt zu einem Dünnband mit einer Dicke von max. 10 mm gegossen wird, wobei die Walzen oder Rollen derart stark gekühlt werden, daß das Dünnband im Gießspalt mit einer Abkühlgeschwindigkeit von mindestens 200 K/s abkühlt. Vorzugsweise liegt die Dicke des Dünnbands zwischen 1 und 5 mm. Selbstverständlich schließt die Angabe der erfindungsgemäß verwendeten Stahlzusammensetzung grundsätzlich auch solche Legierungen ein, bei denen der Gehalt derjenigen Legierungselemente gleich null ist, zu denen nur eine maximal zulässige Obergrenze des Gehalts angegeben ist.and in which the steel in a casting gap formed between two rotating rolls or rollers to form a thin strip with a thickness of max. 10 mm is poured, the rollers or rollers being cooled so strongly that the thin strip cools in the casting gap at a cooling rate of at least 200 K / s. The thickness of the thin strip is preferably between 1 and 5 mm. Of course, the specification of the steel composition used according to the invention also includes those alloys in which the content of those alloy elements is zero, for which only a maximum permissible upper limit of the content is specified.
Gemäß weiterer Ausgestaltungen der Erfindung kann der Chrom-Gehalt des Stahls auf 17,00 - 21,00 Gew.-% Cr, der Mangan-Gehalt auf 8,00 - 12,00 Gew.-% Mn und / oder der Stickstoff-Gehalt auf 0,40 - 0,60 Gew.-% N beschränkt sein. Zusätzlich können Gehalte an Ni, Mo und / oder Cu in dem Stahl vorhanden sein.According to further refinements of the invention, the chromium content of the steel can be 17.00-21.00% by weight of Cr, the manganese content can be 8.00-12.00% by weight of Mn and / or the nitrogen content limited to 0.40-0.60 wt% N his. In addition, levels of Ni, Mo and / or Cu may be present in the steel.
Die Gehalte der in der erfindungsgemäß verwendeten Stahlzusammensetzung enthaltenen Legierungselemente sind jeweils hinsichtlich der Wirkung dieser Elemente optimiert. So erhöhen Cr, Mn, Mo, V, Nb und AI die Stickstofflöslichkeit in der Schmelze, während Ni, Cu als Austenitbildner und Si die Stickstofflöslichkeit herabsetzen. Wie erwähnt, wirkt Si jedoch gleichzeitig als Mischkristallhärter. Darüber hinaus wird es zur Kornfeinung eingesetzt und senkt die Stapelfehlerenergie. AI dagegen erhöht die Stapelfehlerenergie. Mo wirkt ebenfalls als Mischkristallhärter und verbessert das Korrosionsverhalten. V wirkt zusätzlich kornfeinend und erhöht die Festigkeit. Die Zugabe von Nb führt zu einer Steigerung der Festigkeit durch Ausscheidungshärtung.The contents of the alloy elements contained in the steel composition used according to the invention are each optimized with regard to the effect of these elements. Cr, Mn, Mo, V, Nb and Al increase the nitrogen solubility in the melt, while Ni, Cu as austenite formers and Si reduce the nitrogen solubility. However, as mentioned, Si also acts as a mixed crystal hardener. It is also used for grain refinement and lowers the stacking error energy. AI, on the other hand, increases the stack fault energy. Mo also acts as a mixed crystal hardener and improves the corrosion behavior. V also has a grain-refining effect and increases strength. The addition of Nb leads to an increase in strength through precipitation hardening.
Die Erfindung macht sich die grundsätzlich bekannte Technik einer Bandgießanlage zunutze, indem sie den Stahl in dem zwischen den Walzen oder Rollen beispielsweise einer Zweirollen-Gießapparatur ("Double roller") gebildeten Gießspalt vergießt und ihn dabei so stark abkühlt, daß es zu einer Verschiebung von primär ferritischen zu in Richtung zu primär austenitschen Erstarrung kommt. Dies ermöglicht es, den in der Schmelze gelösten .Stickstoff in den Stahl zu überführen, denn der Austenit besitzt eine hohe Löslichkeit für Stickstoff. Die Möglichkeit einer derart intensiven Kühlung ist erst durch das Gießen eines Dünnbandes in einem Gießspalt eröffnet, dessen Wände, welche durch die Gießrollen oder -walzen gebildet sind, sich im wesentlichen mit derselben Geschwindigkeit bewegen wie das gegossene Band, so daß ein ständiger, intensiver Wärmeaustausch zwischen den Wänden (Gießrollen / -walze) und dem vergossenen Stahl im Gießspalt gewährleistet ist.The invention makes use of the basically known technology of a strip caster by casting the steel in the casting gap formed between the rolls or rolls, for example a double-roll casting apparatus ("double roller"), and thereby cooling it so much that it causes a displacement of primarily ferritic solidification comes towards primary austenitic solidification. This makes it possible to transfer the nitrogen dissolved in the melt into the steel, because the austenite has a high solubility for nitrogen. The possibility of such intensive cooling is only opened by casting a thin strip in a casting nip, the walls of which are formed by the casting rolls or rollers moving at essentially the same speed as the cast strip, so that a constant, intensive heat exchange between the walls (casting rollers / rollers) and the cast steel in the casting gap is guaranteed.
Durch die intensive, mit hoher Kühlgeschwindigkeit erfolgende Abkühlung ist sichergestellt, daß in der erstarrenden Schmelze möglicherweise entstehende Stickstoff-Gasblasen klein bleiben und der gegen sie gerichtete Druck groß ist. Dies verhindert ein Ausgasen des Stickstoffs im Zuge der Erstarrung. Zusätzlich wird ein solches Austreten von Stickstoff durch den hohen ferrostatischen Druck unterdrückt, der aufgrund der großen Höhe des Schmelzpools im Gießspalt eintritt. Auf diese Weise ist sichergestellt, daß der Druck PN in den gegebenenfalls entstehenden Stickstoff-Gasblasen stets kleiner ist als die Summe aus dem ümgebungsdruck PA, dem ferrostatischen Druck PF und dem Doppelten der Oberflächenspannung σ der Gasblasen bezogen auf den Blasenradius r (d.h. PN < PA+PF+2σ/r) .The intensive cooling, which takes place at a high cooling rate, ensures that nitrogen gas bubbles which may form in the solidifying melt remain small and the pressure directed against them is high. This prevents outgassing of the nitrogen during the solidification. In addition, such leakage of nitrogen is suppressed by the high ferrostatic pressure which occurs due to the large height of the melt pool in the casting gap. In this way it is ensured that the pressure P N in the nitrogen gas bubbles which may arise is always lower than the sum of the ambient pressure P A , the ferrostatic pressure P F and twice the surface tension σ of the gas bubbles in relation to the bubble radius r (ie P N <P A + P F + 2σ / r).
Die rasche Erstarrung des gegossenen Bandes beim Bandgießen eröffnet somit insbesondere in Verbindung mit Stählen der erfindungsgemäß verwendeten Art große Freiheiten hinsichtlich der Wahl derThe rapid solidification of the cast strip during strip casting thus opens up great freedom with regard to the choice of, particularly in connection with steels of the type used according to the invention
Stahlzusammensetzung. Wie erläutert, können durch die rasche Erstarrung größere Mengen an Stickstoff gelöst werden. Legierungselemente, welche die Werkstoffeigenschaften verbessern, können daher ohne Rücksicht auf ihren ggf. negativen Einfluß auf die Stickstofflöslichkeit in größeren Mengen als bei konventioneller Fertigungsweise hinzugegeben werden. Enthält beispielsweise der Stahl höhere Mengen an Si, so wird die bei konventioneller Fertigung aufgrund der langsamen Erstarrung und der damit einhergehenden verstärkten Ferritbildung bestehende Gefahr des Ausgasens von Stickstoff bei erfindungsgemäßer Vorgehensweise unterbunden. Auch im Fall erhöhter Al-Gehalte wird durch die erfindungsgemäß vorgesehene rasche Abkühlung die Bildung von A1N vermieden, welches sich bei langsamerer Abkühlung einstellt. Somit erlaubt es die Erfindung, ohne Rücksicht auf schädliche, durch die langsame Abkühlung bedingte Einflüsse durch geeignete Wahl der AI- und Si- Gehalte den Verformungsmechanismus der jeweils verwendeten Legierung gezielt so einzustellen, daß ein Endprodukt mit optimierten Eigenschaften erhalten wird.Steel composition. As explained, larger amounts of nitrogen can be dissolved by the rapid solidification. Alloy elements that improve the material properties can therefore be added in larger quantities than in conventional manufacturing methods, regardless of their possible negative influence on nitrogen solubility. For example, if the steel contains higher amounts of Si, this is due to conventional manufacturing slow solidification and the associated increased ferrite formation, existing risk of nitrogen outgassing prevented with the procedure according to the invention. Even in the case of increased Al contents, the rapid cooling provided according to the invention avoids the formation of A1N, which occurs with slower cooling. The invention thus allows the deformation mechanism of the alloy used in each case to be adjusted in a targeted manner so that an end product with optimized properties is obtained, regardless of harmful influences caused by the slow cooling, by suitable selection of the Al and Si contents.
Der durch die Erfindung erreichte Kostenvorteil bei der Verarbeitung von an sich schwer umformbaren Stählen der erfindungsgemäß verwendeten Art ist beträchtlich. Dies gilt sowohl für diejenigen bis zu 7 , 5 Gew.-% Mn enthaltenden Stähle, die sich im konventionellen Strangguß vergießen lassen, als auch für solche mehr als 7,5 Gew.-% Mn enthaltenden Stähle, die konventionell nur im Blockguß vergossen und anschließend in mehreren Walzstichen mit gegebenenfalls erforderlichen Wiedererwärmungen auf die gewünschte Enddicke gewalzt werden können.The cost advantage achieved by the invention when processing steels of the type used according to the invention which are difficult to form per se is considerable. This applies both to those steels containing up to 7.5% by weight of Mn, which can be cast in conventional continuous casting, and to those steels containing more than 7.5% by weight of Mn, which conventionally cast only in ingot casting and can then be rolled to the desired final thickness in several passes with any necessary reheating.
Warmband aus stranggußfähiger Legierung kann derzeit auf einer konventionellen Warmbreitbandstraße nur mit Dicken von minimal 3,5 mm gefertigt werden. Die Erzeugung von Kaltband in den typischen Zieldicken von 0,8 - 1,2 mm ist nur durch Zwischenglühung darstellbar. Bei der erfindungsgemäßen Vorgehensweise über den Bandguß ist demgegenüber aufgrund der geringeren Dicke des erhaltenen Warmbandes eine Zwischenglühung nicht mehr notwendig. Da durch das erfindungsgemäß vorgesehene Bandgießen ein Dünnband erzeugt werden kann, dessen Enddicken zwischen 1 und 3 mm liegt, ist es in vielen Fällen zudem möglich, die Enddicke" des erzeugten Bandes so einzustellen, daß ein Kaltwalzen ganz entfallen kann. Auf diese Weise können die durch die geringe Umformbarkeit von Mn- Austeniten hervorgerufenen Probleme bei der konventionellen Fertigungsweise vermieden werden.Hot strip made of continuously cast alloy can currently only be produced on a conventional hot strip mill with a thickness of at least 3.5 mm. The production of cold strip in the typical target thicknesses of 0.8 - 1.2 mm can only be achieved by intermediate annealing. In contrast, in the procedure according to the invention using strip casting, intermediate annealing is no longer necessary due to the smaller thickness of the hot strip obtained. There can be produced by the strip casting according to the invention, a thin strip whose final thickness is between 1 and 3 mm, it is in many cases also possible to adjust the final thickness "of the strip produced so that cold rolling can be omitted entirely. In this way, the the low formability of Mn-austenite-related problems in conventional manufacturing can be avoided.
Die erfindungsgemäße Vorgehensweise ermöglicht es, Stahlbänder und -bleche zu erzeugen, die besonders hohe Stickstoffgehalte von 0,4 bis 0,6 Gew.-% besitzen und denen gleichzeitig bis zu 3 % Aluminium und / oder Silizium zulegiert sind, ohne daß dazu die Stahlerzeugung unter Überdruck erfolgen muß oder besonders hohe Gehalte an Mangan erforderlich sind. Die derart erzeugten Stahlprodukte besitzen bei einer geringen Macroseigerung oder geringer Anzahl grober Einschlüsse ein feinkörniges, isotropes Gefüge. Aufgrund seines AI- und / oder Si-Gehaltes weisen sie zudem eine gegenüber dem Stand der Technik erhöhte Festigkeit und Duktilität auf. Bei einem erfindungsgemäß erzeugten Stahlbland oder -blech kann zudem durch die Legierungswahl die Verfestigung und damit die Energieabsorbtion bei Verformung gezielt eingestellt werden.The procedure according to the invention makes it possible to produce steel strips and sheets which have particularly high nitrogen contents of 0.4 to 0.6% by weight and to which up to 3% of aluminum and / or silicon are alloyed at the same time, without the steel production having to do so must be carried out under excess pressure or particularly high levels of manganese are required. The steel products produced in this way have a fine-grained, isotropic structure with a small macro-segregation or a small number of coarse inclusions. Due to its Al and / or Si content, they also have increased strength and ductility compared to the prior art. In the case of a steel strip or sheet produced according to the invention, the hardening and thus the energy absorption in the event of deformation can also be set in a targeted manner by the choice of alloy.
Vorzugsweise erfolgt das Gießen des Dünnbandes unter einer Schutzgasatmosphäre. Durch das Gießen unter Schutzgas läßt sich auf einfache Weise ein Dünnband mit modifizierter Oberfläche erzeugen, deren Oxidationsgrad gezielt beeinflußt werden kann. So kann eine Zunderbildung vermieden werden. Das derart beschaffene Band kann anschließend ohne die Gefahr eines Verklebens der Walzen in einem Walzgerüst "inline" warmgewalzt werden. Besonders vorteilhaft ist es in diesem Zusammenhang, wenn das Dünnband vor dem Warmwalzen auf eine Walzanfangstemperatur erwärmt wird. Durch diese Temperaturerhöhung lassen sich beim Warmwalzen höhere Umformgrade erzielen.The thin strip is preferably cast under a protective gas atmosphere. By casting under protective gas, a thin strip with a modified surface can be produced in a simple manner, the degree of oxidation of which can be influenced in a targeted manner. In this way, scaling can be avoided. The strip obtained in this way can then be hot-rolled "inline" in a roll stand without the risk of the rollers sticking together. In this context, it is particularly advantageous if the thin strip is heated to an initial rolling temperature before hot rolling. This increase in temperature enables higher degrees of forming to be achieved during hot rolling.
Indem das Warmband nach dem Warmwalzen einer Wärmebehandlung unterzogen wird, kann sein Gefüge gezielt optimiert werden. Dabei kann die Wärmebehandlung eine Glühung und eine anschließende gesteuerte Abkühlung umfassen.By subjecting the hot strip to a heat treatment after hot rolling, its structure can be specifically optimized. The heat treatment can include annealing and subsequent controlled cooling.
Erfindungsgemäß erzeugte Stahlbleche eignen sich aufgrund ihres Eigenschaftsspektrums in besonderer Weise für die Herstellung von Karosserieblechteilen, von insbesondere im allgemeinen Fahrzeugbau und speziell im Automobilbau eingesetzten versteifenden Strukturkomponenten, von Fahrwerksteilen, von Fahrzeugrädern sowie von Kraftstofftanks. Bei all diesen Verwendungen wirken sich die besonders guten Festigkeitseigenschaften von nach dem erfindungsgemäßen Verfahren erzeugten Stahlblechen vorteilhaft auf. Darüber hinaus erweist sich die gute Korrosionsbeständigkeit erfindungsgemäßer Stahlbleche und -bänder bei solchen Verwendungen als vorteilhaft, bei denen sie mit aggressiven Medien, wie beispielsweise Kraftstoffen, in Berührung kommen. Nachfolgend wird die Erfindung anhand einer ein Ausführungsbeispiel darstellenden Zeichnung näher erläutert.Due to their range of properties, steel sheets produced according to the invention are particularly suitable for the production of body sheet metal parts, of stiffening structural components used in particular in general vehicle construction and especially in automobile construction, of chassis parts, of vehicle wheels and of fuel tanks. In all of these uses, the particularly good strength properties of steel sheets produced by the method according to the invention have an advantageous effect. In addition, the good corrosion resistance of steel sheets and strips according to the invention proves to be advantageous in those applications in which they come into contact with aggressive media, such as fuels. The invention is explained in more detail below on the basis of a drawing illustrating an exemplary embodiment.
Die einzige Figur zeigt schematisch eine Bandgießanlage 1. In dieser Anlage wird beispielsweise ein Stahl verarbeitet, der neben den üblichen unvermeidbaren Verunreinigungen (in Gew.-%) 0.08 % C, 0.5 % Si, 10 % Mn, 19 % Cr, 0.5 % N, 0.3 % AI und als Rest Eisen enthält.The single figure shows schematically a strip casting installation 1. In this installation, for example, a steel is processed which, in addition to the usual unavoidable impurities (in% by weight), contains 0.08% C, 0.5% Si, 10% Mn, 19% Cr, 0.5% N , 0.3% AI and the rest contains iron.
Die Bandgießanlage 1 umfaßt eine als "double roller" bezeichnete Zweiwalzen-Gießapparatur, von der in der Figur die um jeweils eine Drehachse gegenläufig rotierenden Walzen 2,3 dargestellt sind. Zwischen den Walzen 2,3 ist ein Gießspalt 4 gebildet, der laufend mit Schmelze befüllt wird, so daß sich oberhalb des Gießspalts 4 ein Schmelzenpool S bildet.The strip caster 1 comprises a “double roller” two-roll casting apparatus, of which the rolls 2, 3, which rotate in opposite directions about an axis of rotation, are shown in the figure. A casting gap 4 is formed between the rollers 2, 3 and is continuously filled with melt, so that a melt pool S is formed above the casting gap 4.
Über nicht dargestellte Kühleinrichtungen werden die Walzen 2,3 während des Gießvorgangs intensiv gekühlt, so daß die in den Gießspalt 4 eintretende Schmelze mit Abkühlgeschwindigkeiten von mehr als 200 K/s primär austenitisch erstarrt und den Gießspalt 4 als Dünnband D mit einer Dicke von 1 bis 5 mm verläßt. Das derart erzeugte Dünnband D durchläuft anschließend einen Ofen 5, in dem es auf eine Walzanfangstemperatur erwärmt wird.Via cooling devices, not shown, the rollers 2, 3 are intensively cooled during the casting process, so that the melt entering the casting gap 4 primarily solidifies austenitically at cooling rates of more than 200 K / s and the casting gap 4 as thin strip D with a thickness of 1 to 5 mm leaves. The thin strip D produced in this way then passes through a furnace 5, in which it is heated to an initial rolling temperature.
Sowohl die Zweiwalzen-Gießeinrichtung mit den Walzen 2,3 als auch der Ofen 5 sind in einer Einhausung 6 untergebracht, in der eine Schutzgasatmosphäre enthalten ist. Durch das Gießen des Dünnbandes D und seine Wiedererwärmung im Ofen 5 unter Schutzgas wird die Entstehung von Zunder auf der Oberfläche des Dünnbandes D weitestgehend vermieden.Both the two-roll casting device with the rolls 2, 3 and the furnace 5 are accommodated in a housing 6 in which a protective gas atmosphere is contained. By casting the thin strip D and reheating it in the furnace 5 under protective gas, the The formation of scale on the surface of the thin strip D is largely avoided.
Das auf Walzanfangstemperatur erwärmte Dünnband D tritt in ein Walzwerk 7 ein, in welchem es auf ein Endmaß warmgewalzt wird. Aufgrund der hohen Walzanfangstemperatur sind dabei große Umformgrade möglich. Das aus dem im wesentlichen zunderfrei in das Walzwerk gelangende Dünnband D gewalzte Warmband W weist nach dem Warmwalzen eine besonders hochwertige Oberfläche auf.The thin strip D heated to the initial rolling temperature enters a rolling mill 7, in which it is hot-rolled to a final dimension. Due to the high initial rolling temperature, large degrees of forming are possible. The hot strip W rolled out of the thin strip D, which reaches the rolling mill essentially without scale, has a particularly high-quality surface after hot rolling.
Nach dem Warmwalzen im Walzwerk 7 wird das Warmband W in einem Durchlaufglühofen 8 geglüht und anschließend unter einer Kühleinrichtung 9 kontrolliert abgekühlt, um sein Gefüge gezielt zu verbessern. Das derart wärmebehandelte Warmband W wird schließlich zu einem Haspel 10 gewickelt.After hot rolling in the rolling mill 7, the hot strip W is annealed in a continuous annealing furnace 8 and then cooled in a controlled manner under a cooling device 9 in order to specifically improve its structure. The hot strip W heat-treated in this way is finally wound into a reel 10.
In der voranstehend erläuterten Weise erzeugtes Stahlband weist gegenüber herkömmlich zusammengesetzten und erzeugten Stahlbändern aufgrund seines durch die schnelle Abkühlung zwischen den Walzen 2,3 der Zweiwalzen- Gießapparatur erzielten hohen Stickstoff-Gehaltes besonders hohe Festigkeit bei gleichzeitig guter Verformbarkeit und ebenso gutem Energieaufnahmevermögen auf.Steel strip produced in the manner explained above has particularly high strength compared to conventionally assembled and produced steel strips due to its high nitrogen content achieved by the rapid cooling between the rolls 2, 3 of the two-roll casting apparatus, and at the same time good deformability and good energy absorption capacity.
In der nachfolgenden Tabelle sind die überlegenen Festigkeitswerte des in der Gießwalzanlage 1 erfindungsgemäß erzeugten Warmbands W den Festigkeitswerten von konventionell durch Strangguß erzeugten Mn-Austenit-Stählen gegenübergestellt. The table below compares the superior strength values of the hot strip W produced according to the invention in the casting and rolling mill 1 with the strength values of Mn austenite steels conventionally produced by continuous casting.
BEZUGSZEICHENREFERENCE NUMBERS
1 Gießwalzanlage1 casting and rolling system
2,3 Walzen2.3 rollers
4 Gießspalt4 casting gap
5 Ofen5 oven
6 Einhausung6 housing
7 Walzwerk7 rolling mill
8 Durchlaufglühofen8 continuous annealing furnace
9 Kühleinrichtung9 cooling device
10 Haspel10 reels
D DünnbandD thin band
W WarmbandW hot strip
S Schmelzenpool S melt pool

Claims

P A T E N T AN S P RÜ C H E PATENT TO SPEECH
1. Verfahren zum Herstellen eines überwiegend aus Mn- Austenit bestehenden Stahlbands (W) oder -blechs,1. Method for producing a steel strip (W) or sheet consisting predominantly of Mn austenite,
- bei dem ein Stahl erschmolzen wird, welcher (in Gew.-%) die folgenden Legierungsbestandteile enthält:- in which a steel is melted, which (in% by weight) contains the following alloy components:
15,00 - 24,00 g. Cr,15.00 - 24.00 g. Cr,
5,00 - 12,00 ,5.00 - 12.00,
"o Mn,"o Mn,
0,10 - 0,60 % N,0.10 - 0.60% N,
0,01 - 0,2 Ό c, max. 3,00 g. AI und / oder Si, max. 0,07 Q.0.01 - 0.2 Ό c, max. 3.00 g. AI and / or Si, max. 0.07 Q.
Ό P, max. 0,05 s, max. 0,5 Nb, max. 0,5 g, Ό V, max. 3,0 g, "o Ni, max. 5,0 g. Mo, max. 2,0 g. Cu sowie als Re;st Eisen iund unvermeidbare Verunreinigungen,Ό P, max. 0.05 s, max. 0.5 Nb, max. 0.5 g, Ό V, max. 3.0 g, "o Ni, max. 5.0 g. Mo, max. 2.0 g. Cu as well as iron, and unavoidable impurities,
undand
bei dem der Stahl in einem zwischen zwei rotierenden Walzen (2,3) oder Rollen gebildeten Gießspalt zu einem Dünnband (D) mit einer Dicke von max. 10 mm gegossen wird, wobei die Walzen (2,3) oder Rollen derart stark gekühlt werden, daß das Dünnband (D) im Gießspalt (4) mit einer Abkühlgeschwindigkeit von mindestens 200 K/s abkühlt.in which the steel in a casting gap formed between two rotating rollers (2, 3) or rollers to form a thin strip (D) with a thickness of Max. 10 mm is poured, the rollers (2, 3) or rollers being cooled to such an extent that the thin strip (D) cools in the casting gap (4) at a cooling rate of at least 200 K / s.
2. Verfahren nach Anspruch 1, d a d u r c h g e k e n n z e i c h n e t, d a ß die Dicke des Dünnbands (D) 1 bis 5 mm beträgt.2. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t, that the thickness of the thin strip (D) is 1 to 5 mm.
3. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß der Stahl 17,00 - 21,00 Gew.-% Cr enthält.3. The method according to any one of the preceding claims, that the steel contains 17.00-21.00 wt.% Cr.
4. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß der Stahl 8,00 - 12,00 Gew.-% Mn enthält.4. The method according to any one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, d a ß the steel contains 8.00 - 12.00 wt .-% Mn.
5. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß der Stahl 0,40 - 0,60 Gew.-% N enthält.5. The method according to any one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, d a ß the steel contains 0.40 - 0.60 wt .-% N.
6. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß der Stahl zusätzlich Gehalte an Ni, Mo und / oder Cu enthält.6. The method according to any one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the steel additionally contains contents of Ni, Mo and / or Cu.
7. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß das Gießen des Dünnbandes (D) unter einer Schutzgasatmosphäre erfolgt.7. The method according to any one of the preceding claims, characterized in that ß the thin strip (D) is poured under a protective gas atmosphere.
8. Verfahren nach einem der voranstehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t, d a ß das Dünnband (D) im Anschluß an das Gießen kontinuierlich zu einem Warmband (W) warmgewalzt wird.8. The method according to any one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t, that the thin strip (D) is continuously hot-rolled to form a hot strip (W) following the casting.
9. Verfahren nach Anspruch 8, d a d u r c h g e k e n n z e i c h n e t, d a ß das Dünnband (D) vor dem Warmwalzen auf eine Walzanfangstemperatur erwärmt wird.9. The method according to claim 8, d a d u r c h g e k e n n z e i c h n e t, that the thin strip (D) is heated to a rolling start temperature before hot rolling.
10. Verfahren nach Anspruch 9, d a d u r c h g e k e n n z e i c h n e t, d a ß die Erwärmung unter Schutzgas erfolgt.10. The method according to claim 9, d a d u r c h g e k e n n z e i c h n e t, that the heating takes place under protective gas.
11. Verfahren nach einem der Ansprüche 8 bis 10, d a d u r c h g e k e n n z e i c h n e t, d a ß das Warmband (W) nach dem Warmwalzen einer Wärmebehandlung unterzogen wird.11. The method according to any one of claims 8 to 10, d a d u r c h g e k e n n e z e c h n e t, that the hot strip (W) is subjected to a heat treatment after hot rolling.
12. Verwendung eines gemäß einem der Ansprüche 1 bis 11 hergestellten Stahlbands als Werkstoff für Karosserieblechteile .12. Use of a steel strip produced according to one of claims 1 to 11 as a material for body panel parts.
13, Verwendung eines gemäß einem der Ansprüche 1 bis 11 hergestellten Stahlbands als Werkstoff für versteifende Strukturkomponenten. 13, Use of a steel strip produced according to one of claims 1 to 11 as a material for stiffening structural components.
14. Verwendung eines gemäß einem der Ansprüche 1 bis 11 hergestellten Stahlbands als Werkstoff für Fahrwerksteile .14. Use of a steel strip produced according to one of claims 1 to 11 as a material for chassis parts.
15. Verwendung eines gemäß einem der Ansprüche 1 bis 11 hergestellten Stahlbands als Werkstoff für Fahrzeugräder .15. Use of a steel strip produced according to one of claims 1 to 11 as a material for vehicle wheels.
16. Verwendung eines gemäß einem der Ansprüche 1 bis 11 hergestellten Stahlbands als Werkstoff für Kraftstofftanks . 16. Use of a steel strip produced according to one of claims 1 to 11 as a material for fuel tanks.
EP01978372A 2000-09-19 2001-09-14 Method for producing a steel strip or sheet consisting predominantly of mn-austenite Expired - Lifetime EP1319091B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10046181A DE10046181C2 (en) 2000-09-19 2000-09-19 Process for producing a steel strip or sheet consisting predominantly of Mn austenite
DE10046181 2000-09-19
PCT/EP2001/010645 WO2002024969A1 (en) 2000-09-19 2001-09-14 Method for producing a steel strip or sheet consisting predominantly of mn-austenite

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EP (1) EP1319091B1 (en)
JP (1) JP2004509762A (en)
KR (1) KR100748256B1 (en)
CN (1) CN100357478C (en)
AT (1) ATE350504T1 (en)
AU (1) AU2002210506A1 (en)
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DE (2) DE10046181C2 (en)
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DE102015005742A1 (en) 2015-05-05 2016-11-10 Dbi Gas- Und Umwelttechnik Gmbh Process for the production of sheet from a stainless, austenitic CrMnNi steel
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ATE350504T1 (en) 2007-01-15
ES2279831T3 (en) 2007-09-01
DE50111818D1 (en) 2007-02-15
CN100357478C (en) 2007-12-26
WO2002024969A1 (en) 2002-03-28
KR100748256B1 (en) 2007-08-10
TW522060B (en) 2003-03-01
DE10046181A1 (en) 2002-04-04
EP1319091B1 (en) 2007-01-03
BR0113950A (en) 2003-07-22
US20040025979A1 (en) 2004-02-12
DE10046181C2 (en) 2002-08-01
CN1659300A (en) 2005-08-24
AU2002210506A1 (en) 2002-04-02
KR20030051660A (en) 2003-06-25
JP2004509762A (en) 2004-04-02

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