EP0966547B1 - Method for producing a highly resistant, very ductile steel strip - Google Patents

Method for producing a highly resistant, very ductile steel strip Download PDF

Info

Publication number
EP0966547B1
EP0966547B1 EP98916911A EP98916911A EP0966547B1 EP 0966547 B1 EP0966547 B1 EP 0966547B1 EP 98916911 A EP98916911 A EP 98916911A EP 98916911 A EP98916911 A EP 98916911A EP 0966547 B1 EP0966547 B1 EP 0966547B1
Authority
EP
European Patent Office
Prior art keywords
steel
several
strip
max
hot
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP98916911A
Other languages
German (de)
French (fr)
Other versions
EP0966547A1 (en
Inventor
Bernhard Engl
Günter STICH
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.)
ThyssenKrupp Steel Europe AG
Original Assignee
ThyssenKrupp Stahl AG
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 ThyssenKrupp Stahl AG filed Critical ThyssenKrupp Stahl AG
Publication of EP0966547A1 publication Critical patent/EP0966547A1/en
Application granted granted Critical
Publication of EP0966547B1 publication Critical patent/EP0966547B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • 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
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • 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
    • C21D2211/002—Bainite
    • 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

Definitions

  • the invention relates to a method for manufacturing a steel strip with a high strength of at least 900 MPa and good formability.
  • the parameters relevant for the forming can be done with high informative value for the practice from the tensile test be won. Especially the elongation at break and the Set the n-value (measure of the hardening capacity) important metrics.
  • the n-value is characteristic of the deformability under a stretch drawing stress. This is the case for most sheet metal parts in a vehicle prevailing deformation mechanism.
  • the n value stands in relatively good agreement with the Yield strength ratio, which is also a practical one usable measure of the strengthening ability of a Represents material.
  • DE-A-3323255 describes a process for the production of high steel strip Strength and good cold formability.
  • the steel defined in DE-A-3323255 lies within the ranges defined in claim 1.
  • the object of the invention is to develop steel strips, which has a high strength, paired with good Formability and high component strength.
  • the special economic importance of The inventive method consists in Production possibility as a hot strip in thicknesses below 2.0 mm, e.g. 1.5 mm.
  • the manufacturing process requires therefore not necessarily the complex manufacturing process cold strip production with the additional steps cold rolling and final annealing.
  • This material concept also includes the Possibility factory applied Surface finishing. For example, a electrolytically deposited zinc layer applied become. The enormous improvement in corrosion protection through a zinc layer can be a known fact be assumed. It is also known that ultra high strength steels for embrittlement by a Hydrogen absorption in the electrolytic Tending to galvanize. It could be shown that the steel strip according to the invention free of these dreaded galvanizing problems remains.
  • Carbon is required for structural hardening and for the formation of fine precipitates.
  • the content should be limited to 0.1 to 0.2%.
  • Silicon increases the hardness of the mixed crystal, which requires at least 0.3%. For reasons of weldability and to avoid unfavorable scale formation, the content should be limited to 0.6%.
  • Manganese at a content of at least 1.5% delays the conversion and causes the formation of hard conversion products. In order to avoid impermissibly strong micro segregations, the content should be max. Limit 2.0%.
  • Phosphorus can be used to further increase solid-solution strengthening, but should not exceed 0.08% for reasons of weldability.
  • Chromium promotes the formation of a bainite-rich final structure in at least 0.3%. In order not to delay the conversion too much, its content should be limited to max. Be limited to 0.80%.
  • Titanium or zirconium can be used to form fine precipitates with a hardening effect.
  • the effect clearly drops at levels above 0.2%.
  • the maximum value is therefore set at 0.2%.
  • Niobium can also be used for precipitation hardening. At least 0.04% should preferably be added. For reasons of effectiveness, the content is limited to max. 0.08% set.
  • Boron improves hardenability at levels in the range of 0.0005 to 0.005%. According to the current state of knowledge, it is used for this purpose in martensitic steel. It has surprisingly been found that boron in the present case also causes a significant increase in strength in the bainitic basic structure with only a slight reduction in formability.
  • the roller end temperature should be in the range of homogeneous Austenite and therefore not below 800 ° C to a sufficiently low deformation resistance guarantee and secondly deformation-induced Keep excretions low.
  • the cooling conditions should be chosen so that a Conversion to pearlite is avoided and the conversion largely in the bainite stage. Shares of Martensite can contribute to further solidification. Of further solidification by excretion of finest particles can be achieved.
  • This is a cooling of roll end temperature with a cooling rate of at least 30 ° C / s required. This cooling process is to finish at a temperature below 600 ° C by the Tape is wound on a reel and then in Coil cools down.
  • Table 1 shows the chemical compositions of the strip steels 1 and 2 and steel 3, a comparative martensitic steel, produced according to the invention.
  • Table 2 shows the characteristic mechanical properties of the strip steels 1 and 2 produced according to the invention and of the comparison steel 3, which was tempered to the values given in Table 2 by a subsequent heat treatment.
  • Strip steel produced according to the invention clearly. He points a higher elongation at break and a better one Yield strength ratio as a measure of the hardening.
  • Table 3 shows the influence of low reel temperature and a subsequent heat treatment on the properties of a strip steel produced according to the invention of the composition of steel 1 in Table 1.
  • Low reel temperatures of preferably 330 ° C can significantly increase the strength properties, see Example 4 in Table 3.
  • Another object of the invention is Achieving the beneficial effect of a subsequent one Heat treatment. It has surprisingly turned out to be found that the thermal treatment of the Steel strip produced according to the invention in the temperature range between 500 and 850 ° C the forming properties still can be further increased.
  • Examples 4, 5 and 6 in Table 3 show the effect such a heat treatment on the steel 1 with the Composition according to Table 1.
  • This property profile is useful for manufacturing of cold-formed parts with a high Energy absorption capacity (example 5a).
  • higher annealing temperatures can lead to high strengths extraordinarily low yield strength ratios or synonymous high consolidation with good Elongation values can be achieved (Examples 5b, 6a to 6c).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)

Description

Die Erfindung betrifft ein Verfahren zur Herstellung eines Bandstahles mit hoher Festigkeit von mind. 900 MPa und guter Umformbarkeit.The invention relates to a method for manufacturing a steel strip with a high strength of at least 900 MPa and good formability.

Die Forderung nach Reduzierung des Treibstoffverbrauchs von Fahrzeugen macht die Anwendung von Leichtbaukonzepten erforderlich. Leichte Konstruktionen können durch eine Verringerung der Blechdicken erreicht werden.
Zum Ausgleich des dadurch bedingten Verlustes an Festigkeit des Bauteils muß die Festigkeit des Werkstoffs erhöht werden. Eine Steigerung der Festigkeit bewirkt normalerweise eine Verminderung der Verformbarkeit. Im Fahrzeugbau eingesetzte Bleche müssen durch eine Umformung in die aus Design- und Funktionsgründen erforderliche Endform gebracht werden. Wenn die Steigerung der Festigkeit und die damit verbundene verschlechterte Umformbarkeit zu groß werden, kommt es zum Versagen beim Umformen durch lokale Einschnürung und Reißen. Aus diesem Grund ist eine Steigerung der Festigkeit begrenzt.
Die Entwicklung von Stählen zielte stets auf eine Verbesserung des Verformbarkeit/Festigkeit-Verhältnisses ab.
Im Festigkeitsbereich unter 500 MPa konnten bereits beachtliche Erfolge hinsichtlich einer Reduzierung der Blechdicke durch Einsatz von phosphorlegierten oder mikrolegierten Stählen erzielt werden. Noch bessere Ergebnisse wurden mit Bake-hardening-Stählen erzielt. Im Festigkeitsbereich zwischen 500 und 800 MPa lieferten die Entwicklungen der Dualphasen- und der TRIP-(Transformation-induced plasticity) Stähle recht gute Umformbarkeitswerte.The demand for reducing the fuel consumption of vehicles makes it necessary to use lightweight construction concepts. Light constructions can be achieved by reducing the sheet thickness.
To compensate for the loss of strength of the component caused by this, the strength of the material must be increased. An increase in strength normally results in a reduction in deformability. Sheets used in vehicle construction must be formed into the final shape required for design and functional reasons. If the increase in strength and the associated deteriorated formability become too great, there is a failure in forming due to local constriction and tearing. For this reason, an increase in strength is limited.
The development of steels has always aimed to improve the formability / strength ratio.
In the strength range below 500 MPa, considerable success has already been achieved in reducing the sheet thickness by using phosphorus-alloyed or micro-alloyed steels. Even better results have been achieved with bake hardening steels. In strength between 500 and 800 MPa the developments of the dual-phase and TRIP (T ransformation- i nduced p lasticity) steels fairly good Umformbarkeitswerte delivered.

Die für die Umformung relevaten Kennwerte können mit hoher Aussagekraft für die Praxis aus dem Zugversuch gewonnen werden. Besonders die Bruchdehnung und der n-Wert (Maß für das Verfestigungsvermögen) stellen wichtige Maßzahlen dar. Der n-Wert ist kennzeichnend für die Verformbarkeit unter einer Streckziehbeanspruchung. Diese ist bei den meisten Blechteilen eines Fahrzeugs der vorherrschende Verformungsmechanismus. Der n-Wert steht in verhältnismäßig guter Übereinstimmung mit dem Streckgrenzenverhältnis, das ebenfalls ein für die Praxis brauchbares Maß für das Verfestigungsvermögen eines Werkstoffs darstellt.The parameters relevant for the forming can be done with high informative value for the practice from the tensile test be won. Especially the elongation at break and the Set the n-value (measure of the hardening capacity) important metrics. The n-value is characteristic of the deformability under a stretch drawing stress. This is the case for most sheet metal parts in a vehicle prevailing deformation mechanism. The n value stands in relatively good agreement with the Yield strength ratio, which is also a practical one usable measure of the strengthening ability of a Represents material.

Um den Vorteil einer Erhöhung der Festigkeit zur Reduzierung der Blechdicke möglichst weitgehend ausnutzen zu können, werden möglichst hohe Werte der Bruchdehnung (A) und des Verfestigungswertes (n-Wert) angestrebt.To take advantage of an increase in strength Use the reduction in sheet thickness as much as possible The highest possible elongation at break values (A) and the consolidation value (n-value) is aimed for.

Stähle mit sehr hohen Festigkeiten über 800 MPa können sehr effizient zur Gewichtsoptimierung von crashrelevanten Teilen, wie Türaufprallträger, Stoßfängerträger, eingesetzt werden. Dazu muß die Blechdicke jedoch von z.B. über 2,0 mm auf Dicken unter 2,0 mm, etwa auf 1,5 mm, abgesenkt werden. Solch höchstfeste Stahlerzeugnisse konnten in der Vergangenheit nur als kaltgewalzte Bleche zur Verfügung gestellt werden. Steels with very high strengths over 800 MPa can very efficient for weight optimization of crash-relevant parts, such as door impact beams, Bumper supports can be used. To do this, the However, sheet thickness of e.g. over 2.0 mm on thicknesses below 2.0 mm, approximately to 1.5 mm. Such ultra high strength steel products could in the past only provided as cold-rolled sheets become.

Vor allem im Bereich höchster Festigkeiten über 800 MPa reichen beim Einsatz herkömmlicher Werkstoffkonzepte zur Herstellung von Kaltband oder Warmband die Verformungseigenschaften nicht aus, um Bleche zu brauchbaren Teilen umzuformen. Die hohe Festigkeit wird dabei durch die Einstellung von martensitischen Gefügen erzielt. Die Streckgrenzen ist aber bei solchen Stählen ebenfalls sehr hoch. Die daraus resultierenden Werte für das Streckgrenzenverhältnis bzw. die Verfestigung sind entsprechend niedrig. Dies führt neben der geringen Umformbarkeit außerdem zu hohen Rückfederungswerten, so daß Preßteile nur schwierig oder gar nicht formgerecht herstellbar sind.Especially in the area of highest strengths over 800 MPa are sufficient when using conventional material concepts Production of cold or hot strip Deformation properties are not sufficient to make sheet metal to transform usable parts. The high strength is thereby by the setting of martensitic structures achieved. The yield strength is however with such steels also very high. The resulting values for are the yield strength ratio or the hardening correspondingly low. This leads to the minor Formability also to high springback values, so that pressed parts are difficult or not conform to shape are producible.

DE-A-3323255 beschreibt ein Verfahren zur Herstellung von Bandstahl mit hoher Festigkeit und guter Kaltverformbarkeit. Der in DE-A-3323255 definierte Stahl liegt innerhalb den Bereichen, die in Anspruch 1 definiert werden.DE-A-3323255 describes a process for the production of high steel strip Strength and good cold formability. The steel defined in DE-A-3323255 lies within the ranges defined in claim 1.

Aufgabe der Erfindung ist nun Bandstähle zu entwickeln, die ein hohes Verfestigungsvermögen, gepaart mit guter Umformbarkeit und hoher Bauteilfestigkeit aufweisen.The object of the invention is to develop steel strips, which has a high strength, paired with good Formability and high component strength.

Zur Lösung dieser Aufgabe wird erfindungsgemäß ein Verfahren vorgeschlagen, bei dem ein Aluminium-beruhigter Stahl, bestehend aus (in Masse-%)

  • 0,10 bis 0,20 % C
  • 0,30 bis 0,60 % Si
  • 1,50 bis 2,00 % Mn
  • max. 0,08 % P
  • 0,30 bis 0,80 % Cr
  • bis 0,40 % Mo
  • bis 0,20 % Ti und/oder Zr
  • bis 0,08 % Nb
  • Rest Fe und unvermeidbare Verunreinigungen
    • erschmolzen, zu Brammen abgegossen wird und anschließend zu Warmband ausgewalzt wird, wobei die Walzendtemperatur oberhalb 880 °C, die Abkühlgeschwindigkeit auf dem Auslaufrollgang mindestens 30 °C/s und die Haspeltemperatur 300 bis 600 °C betragen.To achieve this object, a method is proposed according to the invention in which an aluminum-calmed steel consisting of (in mass%)
  • 0.10 to 0.20% C
  • 0.30 to 0.60% Si
  • 1.50 to 2.00% Mn
  • Max. 0.08% P
  • 0.30 to 0.80% Cr
  • up to 0.40% Mo
  • up to 0.20% Ti and / or Zr
  • up to 0.08% Nb
  • Balance Fe and unavoidable impurities
    • is melted, poured into slabs and then rolled into hot strip, the final roll temperature above 880 ° C, the cooling speed on the run-out roller table at least 30 ° C / s and the reel temperature 300 to 600 ° C.

    Die gezielte Einstellung sehr feiner Mikrostrukturen, bestehend aus weichen und harten Phasen nebeneinander, kombiniert mit einer Verteilung feinster Ausscheidungen, eröffnete die Möglichkeit attraktiver, bisher nicht bekannter Verarbeitungs- und Gebrauchseigenschaften. Eine Gefügehärtung durch Mehrphasigkeit in Verbindung mit Härtung durch Feinkorn und feine Teilchen verursachen dabei einen multiplen Verfestigungsvorgang.The targeted adjustment of very fine microstructures, consisting of soft and hard phases next to each other, combined with a distribution of the finest excretions, opened up the possibility more attractive, so far not known processing and usage properties. A Structural hardening through multiphase in connection with Cause hardening by fine grain and fine particles thereby a multiple hardening process.

    Die besondere wirtschaftliche Bedeutung des erfindungsgemäßen Verfahrens besteht in der Herstellungsmöglichkeit als Warmband in Dicken unter 2,0 mm, z.B. 1,5 mm. Das Herstellungsverfahren erfordert somit nicht unbedingt den aufwendigen Fertigungsprozeß einer Kaltbanderzeugung mit den zusätzlichen Schritten einer Kaltwalzung und abschließenden Glühung.The special economic importance of The inventive method consists in Production possibility as a hot strip in thicknesses below 2.0 mm, e.g. 1.5 mm. The manufacturing process requires therefore not necessarily the complex manufacturing process cold strip production with the additional steps cold rolling and final annealing.

    Das vorliegende Werkstoffkonzept beinhaltet auch die Möglichkeit werkseitig aufgebrachter Oberflächenveredelung. So kann beispielsweise eine elektrolytisch abgeschiedene Zinkschicht aufgebracht werden. Die enorme Verbesserung des Korrosionsschutzes durch eine Zinkschicht kann als bekannte Tatsache vorausgesetzt werden. Weiterhin ist bekannt, daß höchstfeste Stähle zur Versprödung durch eine Wasserstoffaufnahme beim elektrolytischen Verzinkungsvorgang neigen. Es konnte gezeigt werden, daß der erfindungsgemäße Bandstahl frei von diesen gefürchteten Verzinkungsproblemen bleibt. This material concept also includes the Possibility factory applied Surface finishing. For example, a electrolytically deposited zinc layer applied become. The enormous improvement in corrosion protection through a zinc layer can be a known fact be assumed. It is also known that ultra high strength steels for embrittlement by a Hydrogen absorption in the electrolytic Tending to galvanize. It could be shown that the steel strip according to the invention free of these dreaded galvanizing problems remains.

    Im folgenden werden die Bedeutung der Legierungselemente und der Fertigungsparameter beschrieben.The following are the meaning of the alloying elements and the manufacturing parameters are described.

    Kohlenstoff wird zur Gefügehärtung und zur Bildung von Feinstausscheidungen benötigt. Aus Gründen der Schweißbarkeit sollte der Gehalt auf 0,1 bis 0,2 % begrenzt werden. Carbon is required for structural hardening and for the formation of fine precipitates. For reasons of weldability, the content should be limited to 0.1 to 0.2%.

    Silizium erhöht die Härte des Mischkristalls, wozu mindestens 0,3 % erforderlich sind. Aus Gründen der Schweißbarkeit und zur Vermeidung ungünstiger Zunderausbildung ist der Gehalt auf 0,6 % zu begrenzen. Silicon increases the hardness of the mixed crystal, which requires at least 0.3%. For reasons of weldability and to avoid unfavorable scale formation, the content should be limited to 0.6%.

    Mangan bei einem Gehalt von mindestens 1,5 % verzögert die Umwandlung und bewirkt die Bildung harter Umwandlungsprodukte. Zur Vermeidung unzulässig starker Mikroseigerungen ist der Gehalt auf max. 2,0 % zu begrenzen. Manganese at a content of at least 1.5% delays the conversion and causes the formation of hard conversion products. In order to avoid impermissibly strong micro segregations, the content should be max. Limit 2.0%.

    Phosphor kann zur weiteren Steigerung der Mischkristallverfestigung eingesetzt werden, sollte aber aus Gründen der Schweißbarkeit einen Gehalt von 0,08 % nicht übersteigen. Phosphorus can be used to further increase solid-solution strengthening, but should not exceed 0.08% for reasons of weldability.

    Chrom fördert bei mindestens 0,3 % die Bildung eines bainitreichen Endgefüges. Um die Umwandlung nicht zu stark zu verzögern, sollte sein Gehalt auf max. 0,80 % begrenzt werden. Chromium promotes the formation of a bainite-rich final structure in at least 0.3%. In order not to delay the conversion too much, its content should be limited to max. Be limited to 0.80%.

    Titan oder Zirkonium lassen sich zur Bildung von Feinstausscheidungen mit aushärtender Wirkung benutzen. Die Wirkung läßt bei Gehalten über 0,2 % deutlich nach. Deshalb ist der Maximalwert auf 0,2 % festgesetzt. Titanium or zirconium can be used to form fine precipitates with a hardening effect. The effect clearly drops at levels above 0.2%. The maximum value is therefore set at 0.2%.

    Niob läßt sich ebenfalls zur Ausscheidungshärtung einsetzen. Es sollten bevorzugt mindestens 0,04 % zulegiert werden. Aus Gründen der Wirksamkeit ist der Gehalt auf max. 0,08 % festgelegt. Niobium can also be used for precipitation hardening. At least 0.04% should preferably be added. For reasons of effectiveness, the content is limited to max. 0.08% set.

    Bor verbessert die Härtbarkeit bei Gehalten im Bereich von 0,0005 bis 0,005 %. Dazu wird es nach dem Kenntnisstand bei martensitisch umwandelnden Stählen eingesetzt. Es hat sich überraschenderweise herausgestellt, daß Bor auch im vorliegenden Fall im bainitischen Grundgefüge eine signifikante Steigerung der Festigkeit bei nur geringer Erniedrigung der Umformbarkeit hervorruft. Boron improves hardenability at levels in the range of 0.0005 to 0.005%. According to the current state of knowledge, it is used for this purpose in martensitic steel. It has surprisingly been found that boron in the present case also causes a significant increase in strength in the bainitic basic structure with only a slight reduction in formability.

    Die Walzenendtemperatur sollte im Bereich des homogenen Austenits und damit nicht unter 800 °C liegen, um zum einen ausreichend niedrige Formänderungswiderstände zu gewährleisten und zum anderen verformungsinduzierte Ausscheidungen gering zu halten.The roller end temperature should be in the range of homogeneous Austenite and therefore not below 800 ° C to a sufficiently low deformation resistance guarantee and secondly deformation-induced Keep excretions low.

    Die Abkühlbedingungen sind so zu wählen, daß eine Umwandlung zu Perlit vermieden wird und die Umwandlung weitestgehend in der Bainitstufe erfolgt. Anteile von Martensit können zu weiterer Verfestigung beitragen. Des weiteren soll eine Verfestigung durch Ausscheidung von feinsten Teilchen erzielt werden. Dazu ist eine Abkühlung von Walzendtemperatur mit einer Abkühlgeschwindigkeit von mindestens 30 °C/s erforderlich. Dieser Abkühlvorgang ist bei einer Temperatur unter 600 °C zu beenden, indem das Band auf einen Haspel aufgewickelt wird und danach im Coil abkühlt.The cooling conditions should be chosen so that a Conversion to pearlite is avoided and the conversion largely in the bainite stage. Shares of Martensite can contribute to further solidification. Of further solidification by excretion of finest particles can be achieved. This is a cooling of roll end temperature with a cooling rate of at least 30 ° C / s required. This cooling process is to finish at a temperature below 600 ° C by the Tape is wound on a reel and then in Coil cools down.

    Die Erfindung wird anhand der nachfolgenden Beispiele beschrieben. The invention is illustrated by the following examples described.

    In Tabelle 1 sind die chemischen Zusammensetzungen der erfindungsgemäß hergestellten Bandstähle 1 und 2 und Stahl 3, einem martensitischen Vergleichsstahl, mitgeteilt. Table 1 shows the chemical compositions of the strip steels 1 and 2 and steel 3, a comparative martensitic steel, produced according to the invention.

    In der Tabelle 2 sind die kennzeichnenden mechanischen Eigenschaften der erfindungsgemäß erzeugten Bandstähle 1 und 2 und des Vergleichsstahls 3, der durch eine nachgeschaltete Wärmebehandlung auf die in Tabelle 2 angegebenen Werte angelassen wurde, aufgeführt. Table 2 shows the characteristic mechanical properties of the strip steels 1 and 2 produced according to the invention and of the comparison steel 3, which was tempered to the values given in Table 2 by a subsequent heat treatment.

    Ein Eigenschaftsvergleich weist die großen Vorteile des erfindungsgemäß erzeugten Bandstahls klar auf. Er weist eine höhere Bruchdehnung und ein besseres Streckgrenzenverhältnis als Maß für die Verfestigung auf.A comparison of properties shows the great advantages of Strip steel produced according to the invention clearly. He points a higher elongation at break and a better one Yield strength ratio as a measure of the hardening.

    Tabelle 3 zeigt den Einfluß niedriger Haspeltemperatur und einer nachfolgenden Wärmebehandlung auf die Eigenschaften eines erfindungsgemäß erzeugten Bandstahls der Zusammensetzung des Stahls 1 in Tabelle 1 auf.
    Durch niedrige Haspeltemperaturen von vorzugsweise 330 °C können deutlich Steigerungen der Festigkeitseigenschaften erreicht werden, siehe Beispiel 4 in Tabelle 3.     Table 3 shows the influence of low reel temperature and a subsequent heat treatment on the properties of a strip steel produced according to the invention of the composition of steel 1 in Table 1.
    Low reel temperatures of preferably 330 ° C can significantly increase the strength properties, see Example 4 in Table 3.

    Ein weiterer Gegenstand der Erfindung besteht in der Erzielung der vorteilhaften Wirkung einer nachfolgenden Wärmebehandlung. Es hat sich überraschenderweise herausgestellt, daß durch die thermische Behandlung des erfindungsgemäß erzeugten Bandstahls im Temperaturbereich zwischen 500 und 850 °C die Umformeigenschaften noch weiter gesteigert werden können. Another object of the invention is Achieving the beneficial effect of a subsequent one Heat treatment. It has surprisingly turned out to be found that the thermal treatment of the Steel strip produced according to the invention in the temperature range between 500 and 850 ° C the forming properties still can be further increased.

    Die Beispiele 4, 5 und 6 in Tabelle 3 zeigen die Wirkung einer solchen Wärmebehandlung an dem Stahl 1 mit der Zusammensetzung gemäß Tabelle 1. Dadurch wird ein Werkstoffzustand erreicht, der Vorteile für Bauteile bietet, die insgesamt noch hohe Festigkeiten, vor allem Streckgrenzen bei guter Umformbarkeit, aufweisen müssen. Dieses Eigenschaftsbild bietet sich für die Herstellung von kaltprofilierten Teilen mit einem hohen Energieaufnahmevermögen an (Beispiel 5a). Durch Wahl höherer Glühtemperaturen können hohe Festigkeiten bei außerordentlich niedrigen Streckgrenzenverhältnissen bzw. gleichbedeutend hoher Verfestigung bei guten Dehnungswerten erreicht werden (Beispiele 5b, 6a bis 6c).Examples 4, 5 and 6 in Table 3 show the effect such a heat treatment on the steel 1 with the Composition according to Table 1. This is a Material condition reached, the advantages for components offers overall high strengths, above all Yield strengths with good formability. This property profile is useful for manufacturing of cold-formed parts with a high Energy absorption capacity (example 5a). By choice higher annealing temperatures can lead to high strengths extraordinarily low yield strength ratios or synonymous high consolidation with good Elongation values can be achieved (Examples 5b, 6a to 6c).

    Viele warmgewalzte Erzeugnisse zeigen den Nachteil, daß sie ihre vorteilhaften Eigenschaften verlieren, wenn sie anschließend kaltgewalzt und rekristallisierend geglüht werden. Für den erfindungsgemäß erzeugten Bandstahl wurde jedoch gefunden, daß er auch nach anschließendem Kaltwalzen und Glühen ebenfalls vorteilhafte Eigenschaften aufweist. So zeigt Beispiel 7 in Tabelle 3, daß der erfindungsgemäß erzeugte Bandstahl 1 nach einer Kaltwalzung mit 50 % Verformungsgrad und anschließender Glühung ebenfalls hohe Festigkeiten bei noch weiter verbessertem Streckgrenzenverhältnis gegenüber den nur warmgewalzten Bandstählen 1 und 2 erreicht. (Masse-%) Stahl C Si Mn P S Al N Cr Mo Ti 1 0,14 0,47 1,83 0,007 0,002 0,025 0,004 0,34 0,12 0,15 2a 0,19 0,43 1,67 0,013 0,007 0,032 0,007 0,49 0,30 0,18 2b 0,17 0,53 1,82 0,013 0,012 0,049 0,012 0,77 0,02 0,18 3 0,15 0,01 1,75 0,011 0,003 0,020 0,004 0,55 0,01 0,003 Stahl Probenlage Re N/mm2 Rm N/mm2 Re/Rm Ag % A5 % A80 % WET °C HT °C 1 längs 653 1065 0,61 8 18 11 910 530 quer 652 1098 0,59 8 17 12 2a längs 670 1115 0,60 7 16 10 880 550 2b längs 680 1140 0,60 7 15 9 880 550 3 längs 1050 1096 0,96 2 10 5 880 280

  • Re - Streckgrenze
  • Rm - Zugfestigkeit
  • Ag - Gleichmaßdehnung
  • A5 - Bruchdehnung
  • A80 - Bruchdehnung
  • WET - Walzendtemperatur
  • HT - Haspeltemperatur
    • Beispiel Glühung Re Rm Re/Rm A80 WET HT °C min N/mm2 N/mm2 °C °C 4 ./. ./. 1203 1395 0,86 3 910 330 5a 600 120 1040 1070 0,97 9 910 330 5b 750 1 690 1190 0,58 7 910 330 6a 750 1 620 1095 0,58 6 910 530 6b 800 1 600 1086 0,55 10 910 530 6c 850 1 492 913 0,54 14 910 530 7a 800 1 627 1149 0,55 8 910 530 7b 850 1 446 959 0,47 12 910 530 Many hot-rolled products have the disadvantage that they lose their advantageous properties if they are subsequently cold-rolled and recrystallized annealed. However, it was found for the strip steel produced according to the invention that it also has advantageous properties even after subsequent cold rolling and annealing. Example 7 in Table 3 shows that the strip steel 1 produced according to the invention after cold rolling with a 50% degree of deformation and subsequent annealing likewise achieves high strengths with an even further improved yield strength ratio compared to the only hot-rolled strip steels 1 and 2. (Dimensions-%) steel C. Si Mn P S Al N Cr Mon Ti 1 0.14 0.47 1.83 0.007 0.002 0.025 0.004 0.34 0.12 0.15 2a 0.19 0.43 1.67 0.013 0.007 0.032 0.007 0.49 0.30 0.18 2 B 0.17 0.53 1.82 0.013 0.012 0.049 0.012 0.77 0.02 0.18 3rd 0.15 0.01 1.75 0.011 0.003 0.020 0.004 0.55 0.01 0.003 steel Sample location R e N / mm 2 R m N / mm 2 R e / R m A g % A 5 % A 80 % WET ° C HT ° C 1 along 653 1065 0.61 8th 18th 11 910 530 across 652 1098 0.59 8th 17th 12th 2a along 670 1115 0.60 7 16 10 880 550 2 B along 680 1140 0.60 7 15 9 880 550 3rd along 1050 1096 0.96 2 10 5 880 280
  • R e - yield strength
  • R m - tensile strength
  • A g - uniform expansion
  • A 5 - Elongation at break
  • A 80 - Elongation at break
  • WET - final roll temperature
  • HT - reel temperature
    • example Annealing R e R m R e / R m A 80 WET HT ° C min N / mm 2 N / mm 2 ° C ° C 4th ./. ./. 1203 1395 0.86 3rd 910 330 5a 600 120 1040 1070 0.97 9 910 330 5b 750 1 690 1190 0.58 7 910 330 6a 750 1 620 1095 0.58 6 910 530 6b 800 1 600 1086 0.55 10 910 530 6c 850 1 492 913 0.54 14 910 530 7 a 800 1 627 1149 0.55 8th 910 530 7 b 850 1 446 959 0.47 12th 910 530

    Claims (15)

    1. A method for producing aluminium-killed steel strip with a high-strength of at least 900 MPa and good workability, comprising (in mass %)
      0.10 to 0.20 % C
      0.30 to 0.60 % Si
      1.50 to 2.00 % Mn
      max. 0.08 % P
      0.30 to 0.80 % Cr
      up to 0.40 % Mo
      up to 0.20 % Ti and/or Zr
      up to 0.08 % Nb
      the remainder being Fe and unavoidable impurities;
      said steel strip being melted, poured to form slabs and then rolled to form hot strip, with the final rolling temperature exceeding 880 °C, the rate of cooling on the delivery table being at least 30 °C/s and the coiling temperature ranging from 300 to 600 °C.
    2. The method according to claim 1, characterised in that the hot strip is coiled at a temperature of max. 550 °C.
    3. The method according to claim 1, characterised in that the hot strip is coiled at max. 350 °C.
    4. The method according to one of claims 1 to 3, characterised in that the hot strip is coiled not below 330 °C.
    5. The method according to one or several of claims 1 to 4, characterised in that the hot strip is rolled to a final thickness of max. 2.0 mm.
    6. The method according to one or several of claims 1 to 5, characterised in that the hot strip is skin pass rolled.
    7. The method according to one or several of claims 1 to 6, characterised in that the strip is pickled and metal coated.
    8. The method according to claim 7, characterised in that the metallic coating is applied electrolytically.
    9. The method according to claim 7, characterised in that the metallic coating is applied in a hot-dip galvanising process.
    10. The method according to one or several of claims 1 to 6, characterised in that the hot strip is annealed in a range between 500 and 850 °C.
    11. The method according to one or several of claims 1 to 6, characterised in that after hot rolling, cold rolling of at least 30 % and continuous annealing at temperatures between 700 and 900 °C are carried out.
    12. The method according to one of claims 1 to 11, characterised in that max. 0.15 % Mo is added to the steel by alloying.
    13. The method according to one or several of claims 1 to 12, characterised in that at least 0.04 % Ti and/or Zr are/is added to the steel by alloying.
    14. The method according to one or several of claims 1 to 13, characterised in that 0.0005 to 0.005 % B is added to the steel by alloying.
    15. The method according to one or several of claims 1 to 14, characterised in that at least 0.04 % Nb is added to the steel by alloying.
    EP98916911A 1997-03-13 1998-03-10 Method for producing a highly resistant, very ductile steel strip Expired - Lifetime EP0966547B1 (en)

    Applications Claiming Priority (3)

    Application Number Priority Date Filing Date Title
    DE19710125A DE19710125A1 (en) 1997-03-13 1997-03-13 Process for the production of a steel strip with high strength and good formability
    DE19710125 1997-03-13
    PCT/EP1998/001376 WO1998040522A1 (en) 1997-03-13 1998-03-10 Method for producing a highly resistant, very ductile steel strip

    Publications (2)

    Publication Number Publication Date
    EP0966547A1 EP0966547A1 (en) 1999-12-29
    EP0966547B1 true EP0966547B1 (en) 2001-10-04

    Family

    ID=7823066

    Family Applications (1)

    Application Number Title Priority Date Filing Date
    EP98916911A Expired - Lifetime EP0966547B1 (en) 1997-03-13 1998-03-10 Method for producing a highly resistant, very ductile steel strip

    Country Status (11)

    Country Link
    EP (1) EP0966547B1 (en)
    CN (1) CN1082549C (en)
    AR (1) AR010130A1 (en)
    AT (1) ATE206472T1 (en)
    CA (1) CA2284124A1 (en)
    CZ (1) CZ290944B6 (en)
    DE (2) DE19710125A1 (en)
    ES (1) ES2165157T3 (en)
    PL (1) PL186831B1 (en)
    WO (1) WO1998040522A1 (en)
    ZA (1) ZA982115B (en)

    Cited By (5)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    EP0966090A2 (en) 1998-06-17 1999-12-22 Black & Decker Inc. Method & apparatus for charging batteries
    EP1577412A1 (en) † 2002-12-24 2005-09-21 Nippon Steel Corporation High strength steel sheet exhibiting good burring workability and excellent resistance to softening in heat-affected zone and method for production thereof
    EP2028282A1 (en) 2007-08-15 2009-02-25 ThyssenKrupp Steel AG Dual-phase steel, flat product made of such dual-phase steel and method for manufacturing a flat product
    EP1399598B2 (en) † 2001-06-26 2011-02-23 ThyssenKrupp Steel Europe AG Method for producing high-strength cold-formed steel products from a hot rolled strip, said products exhibiting good malleability
    EP2489748A1 (en) 2011-02-18 2012-08-22 ThyssenKrupp Steel Europe AG Hot-rolled steel surface product produced from a complex phase steel and method for the manufacture

    Families Citing this family (26)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    CN1117884C (en) * 1998-09-29 2003-08-13 川崎制铁株式会社 High strength thin steel sheet, high strength alloyed hot-dip zinc-coated steel sheet, and method for producing them
    DE29818244U1 (en) * 1998-10-13 1998-12-24 Benteler Werke Ag Steel alloy
    DE19937271C2 (en) 1999-08-06 2003-01-09 Hille & Mueller Gmbh & Co Process for the production of deep-drawn or ironable, refined cold strip, and cold strip, preferably for the production of cylindrical containers and in particular battery containers
    EP1143022B1 (en) * 1999-09-16 2010-04-14 JFE Steel Corporation Method for producing a thin steel plate having high strength
    FR2807068B1 (en) * 2000-03-29 2002-10-11 Usinor HOT ROLLED STEEL WITH VERY HIGH LIMIT OF ELASTICITY AND MECHANICAL STRENGTH FOR USE IN PARTICULAR FOR THE PRODUCTION OF PARTS OF MOTOR VEHICLES
    JP4085583B2 (en) 2001-02-27 2008-05-14 Ｊｆｅスチール株式会社 High-strength cold-rolled galvanized steel sheet and method for producing the same
    EP1288322A1 (en) * 2001-08-29 2003-03-05 Sidmar N.V. An ultra high strength steel composition, the process of production of an ultra high strength steel product and the product obtained
    DE10153234A1 (en) * 2001-10-31 2003-05-22 Thyssenkrupp Stahl Ag Hot-rolled steel strip intended for the production of non-grain-oriented electrical sheet and method for its production
    DE10161465C1 (en) * 2001-12-13 2003-02-13 Thyssenkrupp Stahl Ag Production of hot strip used in vehicle chassis comprises casting steel into pre-material, hot rolling to form hot strip, cooling in first cooling step, and cooling in second cooling step after pause to coiling temperature
    FR2847271B1 (en) * 2002-11-19 2004-12-24 Usinor METHOD FOR MANUFACTURING AN ABRASION RESISTANT STEEL SHEET AND OBTAINED SHEET
    FR2847270B1 (en) * 2002-11-19 2004-12-24 Usinor METHOD FOR MANUFACTURING AN ABRASION RESISTANT STEEL SHEET AND OBTAINED SHEET
    US10071416B2 (en) 2005-10-20 2018-09-11 Nucor Corporation High strength thin cast strip product and method for making the same
    US9999918B2 (en) 2005-10-20 2018-06-19 Nucor Corporation Thin cast strip product with microalloy additions, and method for making the same
    US9149868B2 (en) 2005-10-20 2015-10-06 Nucor Corporation Thin cast strip product with microalloy additions, and method for making the same
    PL1918402T3 (en) * 2006-10-30 2009-10-30 Thyssenkrupp Steel Ag Process for manufacturing steel flat products from a steel forming a complex phase structure
    PL1918405T3 (en) * 2006-10-30 2009-10-30 Thyssenkrupp Steel Ag Process for manufacturing steel flat products from silicon alloyed multi phase steel
    ES2325962T3 (en) * 2006-10-30 2009-09-25 Thyssenkrupp Steel Ag PROCEDURE FOR MANUFACTURING STEEL FLAT PRODUCTS FROM A MICROALEATED MULTIPHASIC STEEL WITH BORO.
    ES2367713T3 (en) * 2007-08-15 2011-11-07 Thyssenkrupp Steel Europe Ag STEEL OF DUAL PHASE, FLAT PRODUCT OF A STEEL OF DUAL PHASE SIZE AND PROCEDURE FOR THE MANUFACTURE OF A FLAT PRODUCT.
    CN101555574B (en) * 2008-04-11 2011-06-15 宝山钢铁股份有限公司 Wear-resistant steel with high resistance to tempering and manufacturing method thereof
    US20110277886A1 (en) 2010-02-20 2011-11-17 Nucor Corporation Nitriding of niobium steel and product made thereby
    DE102010056264C5 (en) * 2010-12-24 2020-04-09 Voestalpine Stahl Gmbh Process for producing hardened components
    CN102864377B (en) * 2012-09-10 2015-05-20 山西太钢不锈钢股份有限公司 Hot rolled strip steel and manufacturing method thereof
    DE112015005690T8 (en) 2014-12-19 2018-04-19 Nucor Corporation Hot rolled martensitic lightweight sheet steel and method of making the same
    CN105624570A (en) * 2016-03-10 2016-06-01 绵阳市联合传动科技有限公司 High-strength low-carbon alloy steel brake drum
    CN107653361B (en) * 2017-10-14 2020-02-18 上海鑫昌众星实业有限公司 Preparation process for deep-processed automobile steel plate
    DE102018122901A1 (en) * 2018-09-18 2020-03-19 Voestalpine Stahl Gmbh Process for the production of ultra high-strength steel sheets and steel sheet therefor

    Family Cites Families (9)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    DE2201855C2 (en) * 1972-01-15 1982-03-04 Estel Hoesch Werke Ag, 4600 Dortmund Process for the production of high-strength, easily weldable and cold-deformable heavy and medium plates and their use
    JPS52114518A (en) * 1976-03-24 1977-09-26 Sumitomo Metal Ind Ltd Production of hot rolled high tensile steel material having excellent bending workability
    AU527097B2 (en) * 1979-01-12 1983-02-17 Nippon Steel Corporation Artifically aged low yield to tensile strength ratio high strength steel sheet
    DE3007560A1 (en) * 1980-02-28 1981-09-03 Kawasaki Steel Corp., Kobe, Hyogo METHOD FOR PRODUCING HOT-ROLLED SHEET WITH LOW STRETCH STRESS, HIGH TENSILE STRENGTH AND EXCELLENT SHAPING CAPACITY
    JPS5877528A (en) * 1981-10-31 1983-05-10 Nippon Steel Corp Manufacture of high tensile steel with superior toughness at low temperature
    JPS58185719A (en) * 1982-04-20 1983-10-29 Kobe Steel Ltd Manufacture of high yield ratio type unnormalized hot-rolled high-tension steel plate
    US4472208A (en) * 1982-06-28 1984-09-18 Sumitomo Metal Industries, Ltd. Hot-rolled high tensile titanium steel plates and production thereof
    JPS60190518A (en) * 1984-03-12 1985-09-28 Kobe Steel Ltd Manufacture of high tension steel having superior cold workability and requiring no heat treatment
    TW363082B (en) * 1994-04-26 1999-07-01 Nippon Steel Corp Steel sheet having high strength and being suited to deep drawing and process for producing the same

    Cited By (8)

    * Cited by examiner, † Cited by third party
    Publication number Priority date Publication date Assignee Title
    EP0966090A2 (en) 1998-06-17 1999-12-22 Black & Decker Inc. Method & apparatus for charging batteries
    EP1399598B2 (en) † 2001-06-26 2011-02-23 ThyssenKrupp Steel Europe AG Method for producing high-strength cold-formed steel products from a hot rolled strip, said products exhibiting good malleability
    EP1577412A1 (en) † 2002-12-24 2005-09-21 Nippon Steel Corporation High strength steel sheet exhibiting good burring workability and excellent resistance to softening in heat-affected zone and method for production thereof
    EP1577412B2 (en) † 2002-12-24 2014-11-12 Nippon Steel & Sumitomo Metal Corporation High strength steel sheet exhibiting good burring workability and excellent resistance to softening in heat-affected zone and method for production thereof
    EP2028282A1 (en) 2007-08-15 2009-02-25 ThyssenKrupp Steel AG Dual-phase steel, flat product made of such dual-phase steel and method for manufacturing a flat product
    EP2028282B1 (en) * 2007-08-15 2012-06-13 ThyssenKrupp Steel Europe AG Dual-phase steel, flat product made of such dual-phase steel and method for manufacturing a flat product
    EP2489748A1 (en) 2011-02-18 2012-08-22 ThyssenKrupp Steel Europe AG Hot-rolled steel surface product produced from a complex phase steel and method for the manufacture
    WO2012110165A1 (en) 2011-02-18 2012-08-23 Thyssenkrupp Steel Europe Ag Hot rolled flat steel product produced from a complex phase steel, and method for producing same

    Also Published As

    Publication number Publication date
    WO1998040522A1 (en) 1998-09-17
    PL186831B1 (en) 2004-03-31
    CN1082549C (en) 2002-04-10
    CZ290944B6 (en) 2002-11-13
    ATE206472T1 (en) 2001-10-15
    DE19710125A1 (en) 1998-09-17
    CN1252105A (en) 2000-05-03
    PL335639A1 (en) 2000-05-08
    CZ321999A3 (en) 2000-07-12
    AR010130A1 (en) 2000-05-17
    ZA982115B (en) 1998-09-14
    ES2165157T3 (en) 2002-03-01
    CA2284124A1 (en) 1998-09-17
    DE59801637D1 (en) 2001-11-08
    EP0966547A1 (en) 1999-12-29

    Similar Documents

    Publication Publication Date Title
    EP0966547B1 (en) Method for producing a highly resistant, very ductile steel strip
    DE112006003169B4 (en) Steel sheets for hot press forming with excellent heat treatment and impact properties, hot pressed parts produced therefrom and process for their production
    EP1309734B1 (en) Highly stable, steel and steel strips or steel sheets cold-formed, method for the production of steel strips and uses of said steel
    EP2383353B1 (en) High tensile steel containing Mn, steel surface product made from such steel and method for producing same
    EP2028282B1 (en) Dual-phase steel, flat product made of such dual-phase steel and method for manufacturing a flat product
    DE60216934T2 (en) ULTRA-HIGH-STAINLESS STEEL, PRODUCT OF THIS STEEL AND METHOD FOR THE PRODUCTION THEREOF
    DE60133493T2 (en) Hot-dip galvanized steel sheet and process for its production
    EP1200635B1 (en) High tensile steel band or sheet and method for the production thereof
    EP1573075B1 (en) Method for producing a steel product
    EP3655560B1 (en) Flat steel product with a high degree of aging resistance, and method for producing same
    DE60319534T2 (en) HIGH-FIXED COLD-ROLLED STEEL PLATE AND MANUFACTURING METHOD THEREFOR
    EP2094876B1 (en) Process for producing a steel strip comprising a relatively high strength dual phase steel
    DE19610675C1 (en) Dual phase steel for cold rolled sheet or strip - contg. manganese@, aluminium@ and silicon
    DE102006058917A1 (en) High strength steel sheets with excellent ductility and method of making same
    EP0910675B1 (en) Hot-rolled steel strip and method of making it
    DE3046941C2 (en) A method of manufacturing a steel sheet having a two-phase structure
    EP3692178B1 (en) Method for producing a steel strip from an ultrahigh strength multiphase steel
    EP3512968B1 (en) Method for producing a flat steel product made of a manganese-containing steel, and such a flat steel product
    EP1319725B1 (en) Hot strip manufacturing process
    DE112020005673T5 (en) Steel sheet with high strength and high formability and method for its production
    DE102017130237A1 (en) High strength hot rolled flat steel product with high edge crack resistance and high bake hardening potential, a process for producing such a flat steel product
    DE10130774C1 (en) Production of a high strength cold-formed product comprises pre-casting a steel to a pre-material, hot rolling into a hot strip so that the micro-alloying elements remain dissolved, coiling, cold-forming to a product, and annealing
    EP3658307B1 (en) Sheet metal component, produced by hot working a flat steel product, and method for the production thereof
    EP1453984B1 (en) Method for the production of hot strip or sheet from a micro-alloyed steel
    EP1411140B1 (en) Process for manufacturing of cold-rolled steel strips or sheets having excellent formability

    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: 19990911

    AK Designated contracting states

    Kind code of ref document: A1

    Designated state(s): AT BE DE ES FI FR GB IT LU NL SE

    GRAG Despatch of communication of intention to grant

    Free format text: ORIGINAL CODE: EPIDOS AGRA

    GRAG Despatch of communication of intention to grant

    Free format text: ORIGINAL CODE: EPIDOS AGRA

    GRAH Despatch of communication of intention to grant a patent

    Free format text: ORIGINAL CODE: EPIDOS IGRA

    17Q First examination report despatched

    Effective date: 20010110

    GRAH Despatch of communication of intention to grant a patent

    Free format text: ORIGINAL CODE: EPIDOS IGRA

    GRAA (expected) grant

    Free format text: ORIGINAL CODE: 0009210

    AK Designated contracting states

    Kind code of ref document: B1

    Designated state(s): AT BE DE ES FI FR GB IT LU NL SE

    REF Corresponds to:

    Ref document number: 206472

    Country of ref document: AT

    Date of ref document: 20011015

    Kind code of ref document: T

    REF Corresponds to:

    Ref document number: 59801637

    Country of ref document: DE

    Date of ref document: 20011108

    REG Reference to a national code

    Ref country code: GB

    Ref legal event code: IF02

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

    Effective date: 20011227

    ET Fr: translation filed
    REG Reference to a national code

    Ref country code: ES

    Ref legal event code: FG2A

    Ref document number: 2165157

    Country of ref document: ES

    Kind code of ref document: T3

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

    Ref country code: LU

    Payment date: 20020312

    Year of fee payment: 5

    RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

    Owner name: THYSSENKRUPP STAHL AG

    NLT2 Nl: modifications (of names), taken from the european patent patent bulletin

    Owner name: THYSSENKRUPP STAHL AG

    PLBE No opposition filed within time limit

    Free format text: ORIGINAL CODE: 0009261

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

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

    26N No opposition filed
    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: 20030310

    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 NON-PAYMENT OF DUE FEES

    Effective date: 20050310

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

    Ref country code: SE

    Payment date: 20130318

    Year of fee payment: 16

    Ref country code: FI

    Payment date: 20130319

    Year of fee payment: 16

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

    Ref country code: BE

    Payment date: 20130328

    Year of fee payment: 16

    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 NON-PAYMENT OF DUE FEES

    Effective date: 20140310

    REG Reference to a national code

    Ref country code: SE

    Ref legal event code: EUG

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

    Ref country code: SE

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

    Effective date: 20140311

    REG Reference to a national code

    Ref country code: FR

    Ref legal event code: PLFP

    Year of fee payment: 19

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

    Ref country code: DE

    Payment date: 20160324

    Year of fee payment: 19

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

    Ref country code: GB

    Payment date: 20160324

    Year of fee payment: 19

    Ref country code: AT

    Payment date: 20160324

    Year of fee payment: 19

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

    Ref country code: NL

    Payment date: 20160324

    Year of fee payment: 19

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

    Ref country code: ES

    Payment date: 20160324

    Year of fee payment: 19

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

    Ref country code: FR

    Payment date: 20160324

    Year of fee payment: 19

    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: 20140331

    REG Reference to a national code

    Ref country code: DE

    Ref legal event code: R119

    Ref document number: 59801637

    Country of ref document: DE

    REG Reference to a national code

    Ref country code: NL

    Ref legal event code: MM

    Effective date: 20170401

    REG Reference to a national code

    Ref country code: AT

    Ref legal event code: MM01

    Ref document number: 206472

    Country of ref document: AT

    Kind code of ref document: T

    Effective date: 20170310

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

    Effective date: 20170310

    REG Reference to a national code

    Ref country code: FR

    Ref legal event code: ST

    Effective date: 20171130

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

    Ref country code: NL

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

    Effective date: 20170401

    Ref country code: AT

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

    Effective date: 20170310

    Ref country code: FR

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

    Effective date: 20170331

    Ref country code: DE

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

    Effective date: 20171003

    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: 20170310

    REG Reference to a national code

    Ref country code: ES

    Ref legal event code: FD2A

    Effective date: 20180507

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

    Ref country code: ES

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

    Effective date: 20170311