EP1444371B1 - In-line-verfahren zum rekristallisieren von erstarrten grobbändern in unlegiertem stahl und niedrig legiertem stahl - Google Patents

In-line-verfahren zum rekristallisieren von erstarrten grobbändern in unlegiertem stahl und niedrig legiertem stahl Download PDF

Info

Publication number
EP1444371B1
EP1444371B1 EP02793320A EP02793320A EP1444371B1 EP 1444371 B1 EP1444371 B1 EP 1444371B1 EP 02793320 A EP02793320 A EP 02793320A EP 02793320 A EP02793320 A EP 02793320A EP 1444371 B1 EP1444371 B1 EP 1444371B1
Authority
EP
European Patent Office
Prior art keywords
strip
strips
low
making
carbon steel
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
EP02793320A
Other languages
English (en)
French (fr)
Other versions
EP1444371A1 (de
Inventor
Ettore Centro Svilupp Materiali S.p.A. ANELLI
Giorgio Centro Sviluppo Materiali S.P.A. Porcu
Luca ThyssenKrupp Acciai Speciali Terni SARTINI
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.)
Acciai Speciali Terni SpA
Original Assignee
ThyssenKrupp Acciai Speciali Terni SpA
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 Acciai Speciali Terni SpA filed Critical ThyssenKrupp Acciai Speciali Terni SpA
Publication of EP1444371A1 publication Critical patent/EP1444371A1/de
Application granted granted Critical
Publication of EP1444371B1 publication Critical patent/EP1444371B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • 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
    • 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
    • C21D8/0278—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips involving a particular surface treatment
    • 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
    • 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
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following 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
    • 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
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0273—Final recrystallisation annealing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length

Definitions

  • the present invention applies to both Carbon and low-alloyed steel strips, made by direct continuous casting with a twin-roll strip machine, all characterized by the generation of large-size grains (from 150 to 1500 ⁇ m) in the solidified coarse product.
  • the invention refers to an in-line controlled recrystallization treatment carried out on a solidified coarse strip during its roll path transfer, prior to its wrapping on a coiler.
  • a rolling and an annealing rapid heating with holding at preset temperatures for short times
  • Both the rolling and the annealing can be carried out under conditions in which the austenite or the ferrite are stable, or in a mixed-phase field, in which both the austenite and the ferrite are stable.
  • This invention refers to a process for the making of steel strips and sheets, having a thickness ranging from 4.5 to 0.7 mm, corresponding to common- or special-type hot-rolled or cold-rolled and annealed products, using as starting material continuous casting coarse strips and the present in-line recrystallization process.
  • EP 0707908 Al teaches a twin-roll continuous casting apparatus with which a Carbon steel strip is cast under an atmosphere of inert gas, like Ar or N 2 .
  • the strip is then subjected in-line to hot rolling(from 850 to 1350 °C) with a thickness reduction ranging from 5 to 50% and cooled.
  • the thin flat product thus obtained has good strength and ductility properties by virtue of the grain size reduction attained by hot rolling.
  • JP 61689846 and JP 63115654 refer to in-line thermal treatments, without hot rolling, comprising at least a double phase transition prior to the final cooling and wrapping. Said phase transition is effected subjecting the strip to single or multiple heat cycles of the type: cooling, heating, cooling.
  • WO 95/13155 teaches an in-line thermal treatment of cast Carbon steel strip aimed at checking the microstructure of the as-cast strip.
  • the cast strip after an optional single-pass thickness reduction (20-50%) at 900-1100 °C, is cooled below the temperature at which the transformation of austenite into ferrite takes place, and subsequently heated in-furnace at ⁇ 1200°C temperatures until reaustenizing the material (in-line normalization).
  • the austenitic grains are thus refined, and, by checking the strip final cooling and wrapping, sufficiently refined structures providing adequate strength and ductility can be developed.
  • EP 0776984 reports a method and the related equipment for continuously manufacturing metal coils, from a continuous casting system of strips, comprising also the steps of: hot deformation, with a >30% thickness reduction; in-furnace heating thermal treatment under non-oxidizing atmosphere at temperatures of 800-1250 °C (preferably of 1100-1250 °C); cooling, at a 20-40 °C/s rate and down to 100 °C; pickling; and strip wrapping/shearing.
  • the main object of this invention is the connection between the main casting line and the strip pickling-edge trimming-end thermal treatment line, so as to carry out a single continuous step according to which the pickling, the edge trimming, the strip wrapping/shearing lines may independently be connected to the strip casting-rolling-thermal treatment line.
  • the sole example reported relates to a stainless steel, although the metals usable in the invention comprise common and special steels.
  • EP 0760397 discloses an apparatus for stainless steelmaking realizing a process comprising the steps of: casting, cooling, hot deformation (rolling) at various temperatures, complete recrystallization by heating and cooling.
  • Some of the above processes and other alike ones require the introduction of one or more optional cooling systems and of a rolling stand, as well as of an intermediate reheat furnace, located upstream or downstream of the rolling stand onto the roll path transferring the strip to the coiler.
  • the state of the art provides no teachings about the attainment of a Carbon steel or low-alloyed steel product that, from a continuously cast solidified coarse strip, develop the desired mechanical and technological properties, related to hot-rolled or cold-rolled and annealed strips and sheets, exploiting a controlled in-line recrystallization treatment, by rolling in a ferritic, austenitic or mixed-phase field, and direct annealing, also in a subcritical field ( ⁇ Ac 3 in-furnace treatment temperature).
  • in-line recrystallization refers to high-alloyed (stainless) steels that always recrystallize at a very slow rate, as much so as to systematically require treatment temperatures of well above 1050 °C in order to attain a significant recrystallization over short times.
  • An object of the present invention is that of providing an in-line process for the making of strips in Carbon steel and in low-alloyed steel by a controlled recrystallization treatment performed on a solidified coarse strip during the roll path transfer, prior to the wrapping on the coiler.
  • a rolling there are carried out in-line and in rapid succession a rolling, an annealing (rapid heating with holding at preset temperatures for short times in order to attain a near-complete recrystallization of the austenite and/or of the ferrite work hardened during the deformation), and a controlled cooling (optional direct galvanizing included) prior to the wrapping on the coiler.
  • annealing rapid heating with holding at preset temperatures for short times in order to attain a near-complete recrystallization of the austenite and/or of the ferrite work hardened during the deformation
  • a controlled cooling optionally direct galvanizing included
  • This novel process comprises the following steps:
  • Another object of the present invention is to provide strips of Carbon steel and of low-alloyed steel, manufactured with the hereto detailed process, having an end thickness ranging from 4.5 to 0.7 mm and preset microstructure characteristics, capable of developing the following properties, suitable for various application fields:
  • the process of the present invention provides the use of a continuous casting machine having a twin-roll ingot mold (A), all characterized by the formation of large-size grains (150 to 1500 ⁇ m) in the solidified coarse product.
  • cooling devices (B and D) for cooling in a controlled manner the strip continuously crossing them, guided by the pinch rolls (C) of a per se already known construction.
  • the strip is subjected to an adequate force, e.g. acting on the twin rolls, so as to limit the generation of shrinkage cavities. Then, the cast strip is subjected on both faces thereof to cooling in order to slow down the growth both of the austenitic grains and of the surface oxide layer.
  • the cooling cycles of the as-cast steel strips are set acting on the casting rate, the flow rates and the number of active cooling areas (modules).
  • the pair of said cooling systems B and D has modules, individually actuable, variable in the individual sections and capable of effecting onto the strip cooling rates of up to 200 °C/s.
  • cooling is attained with cooling modes selected from the group comprising: natural air, forced air, inert gas jets in an inertized chamber, air-water, water and combinations thereof.
  • a rolling system consisting of one or more stands (E), capable, in one or more passes, of effecting a 15-80% total thickness reduction in order to reduce to acceptable sizes the residual porosities due to the solid contraction and to induce a work hardening of the structure extant at the instant of deformation.
  • the stands are located as close as possible, so as to attain quite short interpass times (shorter than the time required to attain the 50% in volume recrystallization) and to allow deformation accumulation in the material (the greater the accumulated deformation, the more rapid the material recrystallization and the softening kinetics).
  • the hot deformation of the cast strip can take place by means of two consecutive stands, each providing a 15-40% thickness reduction.
  • a rapid heating system aimed at controlling the temperature of the strip inletted in the rolling system (E), according to the steel composition and to the thermomechanical cycle to be carried out.
  • the rapid heating system (R) is located downstream of the controlled cooling system (D).
  • a further system comprising a tunnel insulated under natural air, or inert gas, or combinations thereof, and aimed at holding the temperature of the strip which is about to enter the furnace (G) located nearby E.
  • the insulated section prevents temperature from dropping below Ar 3 and to start a phase transformation before the austenite recrystallization.
  • the furnace (G), of an induction-, gas- or the like type, is capable of operating under a reducing or a non-oxidizing atmosphere, and of rapidly (in less than 12 s) bringing the strip temperature to temperature values ranging from 670 to 1150 °C, apt to attain a near-complete recrystallization of the material (>95 % in volume ) with temperature holding times of 5-40 s.
  • the annealing temperature is selected so as to fall within a completely austenitic field (austenitic field rolling) or a ferritic field (ferritic field rolling) , or within a mixed-phase field in which ferrite and austenite coexist (ferritic or mixed-phase field rolling), as it is indicated in FIG. 2.
  • the cleaning system (H) which removes oxides or oxide residues partially or totally reduced by the furnace atmosphere from the strip surface.
  • a set of at least three controlled cooling modules (I, L, M). These modules are capable of effecting on the strip cooling rates variable in the individual sections and ranging from 800 °C/s (ultrarapid cooling) to 0.01 °C/s (insulation).
  • the strip cooling cycle Upon detecting the strip temperature at the furnace outlet by metering with a suitable device, the strip cooling cycle is defined according to the steel phase transformation characteristics, which mainly depend on the actual size of the austenitic grains and on the chemical analysis of the steel, so as to develop the desired structures.
  • the roll path among the various modules, there are located other temperature meters (e.g., pyrometers), enabling monitoring of the thermal cycle.
  • the latter can be quite complex (e.g., accelerated cooling, in-air cooling, wrapping) in case multiphase microstructures, made of various constituents like polygonal ferrite, bainite, martensite and/or residual austenite, are to be developed.
  • One of the cooling modules is also capable of galvanizing the strip.
  • the strip is wrapped at a temperature of from 900 to 150°C.
  • the present innovative in-line recrystallization treatment of cast coarse strips enables, by selecting the chemical analysis of the steel, to check the rolling and annealing temperatures and the in-line cooling cycles, to develop suitable end microstructures, having definite volume fractions of equiaxic (polygonal) ferrite, pearlite or carbides, of acicular and/or bainitic ferrite and of high-Carbon martensite/residual austenite islands.
  • the different distribution of the microstructural components so obtained, highly checkable through the thermal and microstructural homogenization taking place during the in-furnace recrystallization treatment provides the strips with different combinations of strength, ductility and cold formability.
  • the latter are characterized by having, at the ferrite interface, a high dislocation density with respect to the traditional polygonal ferrite/pearlite structures.
  • the end material yielded has a continuous-type stress-deformation curve, provided with a good mix of strength and ductility. Exploiting a subcritical recrystallization treatment in continuously cast strips, microstructures exhibiting significant quantities of residual austenite (5-20 %) were made.
  • the molten steel was cast in a vertical continuous casting machine (Fig. 1) having a twin-roll ingot mold and a 6 t/m mean separation force.
  • the strips were cooled at the ingot mold outlet until reaching a 1080-1100 °C temperature at the rolling system inlet. A 35% total thickness reduction was effected.
  • the subsequent cooling and heating steps were carried out as it is schematically shown in FIG 2, so as to attain a ⁇ 850 °C minimum temperature Tm, a 10 °C/s heating rate, a 1050 °C maximum temperature of the in-furnace strip, with 10 s holding times thereat. 15 °C/s cooling rates were detected at the furnace outlet and up to the wrapping. The latter was carried out at >750 °C temperatures.
  • microstructural characteristics and the mechanical properties of the end strip in terms of mean size (d) of the ferrite grains, pearlite (P) %, lowest yield value (Re L ), failure strength (Rm), Re L /Rm ratio, ultimate elongation (A), are reported in Table 2.
  • the ratio between the standard deviation and the mean value for the failure strength and for the elongation is of the 2.5% and of the 3%, respectively.
  • FIG. 3 shows the typical microstructure of the strip, as observable at the optical microscope.
  • the molten steel was cast in a vertical continuous casting machine having a twin-roll ingot mold and a 5.5 t/m mean separation force.
  • the strips were cooled at the ingot mold outlet until reaching a 1080-1100 °C temperature at the rolling system inlet. A 35% total thickness reduction was effected.
  • the subsequent cooling and heating steps were carried out as it is schematically shown in FIG. 2, so as to attain a ⁇ 850 °C minimum temperature Tm, an 8 °C/s heating rate, a 1050 °C maximum temperature of the in-furnace strip, with 12 s holding times thereat. 15 °C/s cooling rates were detected at the furnace outlet and up to the wrapping. The latter was carried out at >750 °C temperatures.
  • microstructural characteristics and the mechanical properties of the end strip in terms of mean size (d) of the ferrite grains, pearlite % (P) lowest yield value (Re L ), failure strength (Rm), Re L /Rm ratio, ultimate elongation (A), are reported in Table 4. The ratio between the standard deviation and the mean value for the failure strength is of the 3% and of the 3.5%, respectively.
  • FIG. 4 shows the typical microstructure of the strip, as observable at the optical microscope.
  • the molten steel was cast in a vertical continuous casting machine having a twin-roll ingot mold and a 6 t/m mean separation force.
  • the strips were cooled at the ingot mold outlet until reaching a 690 °C temperature at the rolling system inlet. A 37% total thickness reduction was effected.
  • the subsequent cooling and heating steps were carried out as it is schematically shown in FIG. 2, so as to attain a ⁇ 670 °C minimum temperature Tm 670 °C, a 5 °C/s heating rate, a 720 °C maximum temperature of the in-furnace strip, with 15 s holding times thereat. ⁇ 0.5 °C/s cooling rates were detected at the furnace outlet and up to the wrapping.
  • microstructural characteristics and the mechanical properties of the end strip in terms of mean size (d) of the ferrite grains, lowest yield value (Re L ), failure strength (Rm), Re L /Rm ratio, ultimate elongation (A), are reported in Table 5.
  • the molten steel was cast in a vertical continuous casting machine having a twin-roll ingot mold and a 6.5 t/m mean separation force.
  • the strips were cooled at the ingot mold outlet and then heated until reaching an 840-860 °C temperature at the rolling system inlet. A 40% total thickness reduction was effected.
  • the subsequent cooling and heating steps were carried out as it is schematically shown in FIG. 2, so as to attain a ⁇ 880 °C minimum temperature Tm, an 8 °C/s heating rate, a 1050 °C maximum temperature of the in-furnace strip, with 12 s holding times thereat. Downstream of the furnace the cooling rates were of from 50 °C/s to 700-680 °C/s, 5 s natural air cooling, ⁇ 400 °C forced cooling (40-80 °C/s).
  • the elevated yield value (Rp 0.2 ) and failure strength value Rm are anyhow accompanied by a low yield/failure ratio, a good ductility (>22% elongation), and a particularly high (>16000 MPa%) product of the elongation X failure strength (A X Rm) parameter.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Metal Rolling (AREA)
  • Continuous Casting (AREA)
  • Heat Treatment Of Steel (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Claims (15)

  1. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl mit einem stark überprüften Mirkogefüge, umfassend die folgenden Schritte in dieser Reihenfolge:
    Gießen von Streifen bzw. Bändern in einer kontinuierlichen Doppelwalzen-Gießvorrichtung (twin-roll continuous casting machine) mit einer Dicke in dem Bereich von 1 bis 6 mm und mit einer Zusammensetzung, ausgedrückt als Masse-%, umfassend die folgenden Bestandteile:
    0,02-0,20 C; 0,1-1,6 Mn; 0,02-2,00 Si; <0,05 Al; <0,03 S, <0,1 P; 0,01-1,5 Cr; 0,01-0,5 Ni; <0,5 Mo; 0,003-0,012 N; und gegebenenfalls <0,03 Ti; <0,01 V; <0,035 Nb; <0,005 B; Rest Fe und unvermeidbare Verunreinigungen;
    Geregeltes Abkühlen des Streifens bzw. Bandes in dem Bereich, welcher zwischen den Gusswalzen und einer Walzenanlage (E) vorhanden ist,
    Heißumformen des gegossenen Streifens bzw. Bandes durch die Walzenanlage (E) bei einer Temperatur in dem Bereich von 1150°C bis (Ar1 - 100)°C , bis daran eine Dickeverringerung von 15 bis 80% bewirkt wurde, wobei das Heißumformen aus der Gruppe gewählt wird, umfassend:
    Walzen bei > Ar3 Temperaturen und in einer vollständig austenitischen Phase, wobei Ar3 die Temperatur ist, bei welcher die Umwandlung des kontinuierlich abgekühlten Austenits beginnt;
    Walzen bei einer < Ar1 Temperatur und in einer vollständig ferritischen Phase;
    Walzen bei einer Temperatur in dem Bereich zwischen Ar3 bis Ar1 und unter koexistierenden Bedingungen der austenitischen Phase und der ferritischen Phase;
    Halten des Streifens bzw. Bandes auf einer geregelten Temperatur in einer isolierten Anlage (F), welches zwischen einem Auslaß der Walzenanlage (E) und einem Einlass einer Heizanlage(G) vorhanden ist;
    Erwärmen des Streifens bzw. Bandes mit der Heizanlage (G) bei Temperaturen in dem Bereich von 670°C bis 1150°C für Zeiträume zwischen 5 bis 40 Sekunden, um so eine Rekristallisation von >95% bezüglich des Volumens des Streifens bzw. Bandes zu erzielen;
    Geregeltes Abkühlen des so erhaltenen Streifens bzw. Bandes in dem Bereich, welcher zwischen einem Auslaß der Heizanlage (G) und einer Einwickelanlage enthalten ist, gegebenenfalls mit einer Vielzahl von Wickelvorrichtungen (N,P).
  2. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 1, wobei die Zusammensetzung während des Gießschrittes auch umfasst: <0,03 Ti; <0,10 V; <0,035 Nb und >0,005 B.
  3. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 1 oder 2, wobei das geregelte Abkühlen in dem Bereich, welcher zwischen den Gusswalzen und den Andruckwalzen C und zwischen den Andruckwalzen (C) und der Walzenanlage vorhanden ist, mittels eines Anlagepaares (B und D) durchgeführt wird, mit Komponenten, die einzelnd betätigbar sind, und in den einzelnen Bereichen variierbar sind und in der Lage sind, auf den Streifen bzw. das Band Abkühlgeschwindigkeiten von bis zu 200°C/Sekunde auszuüben.
  4. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 3, wobei das Abkühlen durch Abkühlarten erzielt wird, gewählt aus der Gruppe umfassend: natürliche Luft, Druckluft, Schutzgasdüsen in einer inertisierten Kammer und deren Kombinationen.
  5. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach einem der Ansprüche 1 bis 4, wobei die Heizanlage unter einer reduzierenden oder einer nicht-oxidierenden Atmosphäre betrieben wird.
  6. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 5, wobei die Heizanlage (G) bei Temperaturen betrieben wird, ausgewählt aus der Gruppe umfassend: Temperaturen, welche dem Vorhandensein der alleinigen Austenitphase entspricht, Temperaturen, welche dem Vorhandensein der alleinigen Ferritphase entspricht, Temperaturen, welche dem Vorhandensein einer Koexistenz der Ferritphase und der Austenitphase entspricht.
  7. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 1, wobei die Heizanlage (G) von. einer Anlage (H) zur Reinigung der Streifen- bzw. Bandoberfläche und zur Entfernung von Oxiden und Oxidrückständen gefolgt wird, welche teilweise oder vollständig von der Ofenatmosphäre reduziert sind.
  8. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach einem der Ansprüche 1 bis 7, wobei der Streifen bzw. das Band auf einer geregelten Temperatur an dem Auslaß der Walzenanlage (E) durch eine Anlage (F) gehalten wird, umfassend einen isolierten Tunnel, welcher Luft oder Schutzgas oder deren Kombinationen enthält.
  9. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach einem der Ansprüche 1 bis 8, wobei der Streifen bzw. das Band an dem Auslaß der Heizanlage (H) einem Abkühlen mit wenigstens drei Komponenten (I, L, M) unterworfen wird, welche entlang einer Walzbahn angeordnet sind, die geeignet sind auf den Streifen bzw. das Band Abkühlgeschwindigkeiten auszuüben, welche in dem Bereich von 800°C/Sekunde bis 0,01 °C/Sekunde liegen.
  10. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 9, wobei in einem der wenigstens drei (I, L, M) Komponenten ein Galvanisieren des Streifens bzw. Bandes durchgeführt werden kann.
  11. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach einem der vorangehenden Ansprüchen, wobei die Warmumformung der gegossenen Streifen bzw. Bänder mittels zweier aufeinanderfolgender Walzgerüste durchgeführt wird, welche jeweils eine Dickeverringerung von 15-40% bereitstellen.
  12. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 11, wobei eine Durchlaufzeit zwischen den aufeinanderfolgenden Walzgerüsten kürzer ist als die Dauer um eine Rekristallisation von 50% bezüglich des Volumens zu erzielen.
  13. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 3, wobei eine Anlage (R) zur Erwärmung des Streifens bzw. Bandes in dem Bereich durchgeführt wird, welcher zwischen den Andruckwalzen (C) und der Walzenanlage vorhanden ist.
  14. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach Anspruch 13, wobei die Heizanlage (R) stromabwärts der geregelten Abkühlanlage (D) angeordnet ist.
  15. Verfahren zur Herstellung von Streifen bzw. Bändern aus Kohlenstoffstahl bzw. unlegiertem Stahl und aus niedrig legiertem Stahl nach einem der vorangehenden Ansprüche, wobei der Streifen bzw. das Band bei Temperaturen in dem Bereich von 150 bis 900°C eingewickelt wird.
EP02793320A 2001-11-15 2002-11-15 In-line-verfahren zum rekristallisieren von erstarrten grobbändern in unlegiertem stahl und niedrig legiertem stahl Expired - Lifetime EP1444371B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
ITRM20010678 2001-11-15
IT2001RM000678A ITRM20010678A1 (it) 2001-11-15 2001-11-15 Procedimento per la ricristallizzazione in linea di nastri grezzi di solidificazione in acciai al carbonio e in acciai basso legati e nastri
PCT/IT2002/000728 WO2003062476A1 (en) 2001-11-15 2002-11-15 In-line process for the recrystallization of solidified coarse strips in carbon steel and in low-alloyed steel and so obtainable strips having a highly checked microstructure

Publications (2)

Publication Number Publication Date
EP1444371A1 EP1444371A1 (de) 2004-08-11
EP1444371B1 true EP1444371B1 (de) 2005-04-13

Family

ID=11455880

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02793320A Expired - Lifetime EP1444371B1 (de) 2001-11-15 2002-11-15 In-line-verfahren zum rekristallisieren von erstarrten grobbändern in unlegiertem stahl und niedrig legiertem stahl

Country Status (6)

Country Link
EP (1) EP1444371B1 (de)
CN (1) CN1296498C (de)
AT (1) ATE293174T1 (de)
DE (1) DE60203733T2 (de)
IT (1) ITRM20010678A1 (de)
WO (1) WO2003062476A1 (de)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102005063058B3 (de) * 2005-12-29 2007-05-24 Thyssenkrupp Nirosta Gmbh Verfahren zum Herstellen eines Kaltbands mit ferritischem Gefüge
CN103305754B (zh) * 2012-03-14 2015-09-23 宝山钢铁股份有限公司 一种时效硬化薄带连铸低碳微合金钢带制造方法
CN103305770B (zh) * 2012-03-14 2015-12-09 宝山钢铁股份有限公司 一种薄带连铸550MPa级高强耐大气腐蚀钢带的制造方法
CN103305759B (zh) * 2012-03-14 2014-10-29 宝山钢铁股份有限公司 一种薄带连铸700MPa级高强耐候钢制造方法
CN103302255B (zh) * 2012-03-14 2015-10-28 宝山钢铁股份有限公司 一种薄带连铸700MPa级高强耐大气腐蚀钢制造方法
EP2821520B1 (de) * 2013-07-03 2020-11-11 ThyssenKrupp Steel Europe AG Verfahren zum beschichten von stahlflachprodukten mit einer metallischen schutzschicht
JP6452037B2 (ja) * 2014-02-04 2019-01-16 日立金属株式会社 鋳造方法および鋳造装置
EP4109037A1 (de) 2014-12-16 2022-12-28 Greer Steel Company Stahlzusammensetzungen, verfahren zur herstellung und verwendungen beim produzieren von randfeuerpatronen
CN112517863A (zh) * 2019-09-19 2021-03-19 宝山钢铁股份有限公司 一种高强薄规格花纹钢板/带及其制造方法
CN114669613B (zh) * 2022-04-19 2023-06-20 安徽工业大学 一种柔性辊接触式的薄带组合冷却方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2164343C (en) * 1994-04-04 2002-01-01 Yoshikazu Matsumura Twin-roll type continuous casting method and device
JP2750096B2 (ja) * 1995-05-08 1998-05-13 新日本製鐵株式会社 ストリップ連続鋳造熱間圧延熱処理酸洗設備および酸洗コイルの製造方法
JP3709003B2 (ja) * 1996-01-26 2005-10-19 新日本製鐵株式会社 薄板連続鋳造方法
DZ2531A1 (fr) * 1997-12-19 2003-02-08 Exxon Production Research Co Procédé de préparation d'une tôle d'acier double phase cette tôle et procédé pour renforcer la résistance à la propagation des fissures.

Also Published As

Publication number Publication date
ITRM20010678A1 (it) 2003-05-15
ITRM20010678A0 (it) 2001-11-15
CN1606629A (zh) 2005-04-13
CN1296498C (zh) 2007-01-24
WO2003062476A1 (en) 2003-07-31
DE60203733T2 (de) 2006-02-09
DE60203733D1 (de) 2005-05-19
EP1444371A1 (de) 2004-08-11
ATE293174T1 (de) 2005-04-15

Similar Documents

Publication Publication Date Title
JP5130221B2 (ja) マルチフェイズ構造の熱間ストリップの製造方法
CN110499448B (zh) 一种性能优异的高n奥氏体不锈钢中厚板及其制造方法
KR101476866B1 (ko) 양호한 스탬핑성을 갖는 저밀도 강
JP5350253B2 (ja) ボロンミクロ合金化多相鋼からフラット鋼生成物を製造する方法
EP2711439B1 (de) Dünnes stahlblech mit hohem carbonanteil und herstellungsverfahren dafür
CA2537560C (en) Hot rolled steel sheet and method for manufacturing the same
JP5326709B2 (ja) 低降伏比型高バーリング性高強度熱延鋼板及びその製造方法
CN106048390A (zh) 一种薄板坯连铸连轧生产无取向电工钢50w800的生产方法
EP2712944B1 (de) Dünnes stahlblech mit hohem kohlenstoffgehalt und herstellungsverfahren dafür
WO2022206911A1 (zh) 抗拉强度≥1180MPa的低碳低合金Q＆P钢或热镀锌Q＆P钢及其制造方法
US20150218684A1 (en) Cold-Rolled Flat Steel Product and Method for the Production Thereof
EP3561118B1 (de) Warmgepresstes element aus hochfestem stahlblech mit ausgezeichneter hochtemperaturdehnungseigenschaft und verfahren zu seiner herstellung
CN100352952C (zh) 用于生产晶粒定向电工钢带的工艺
CN102712963A (zh) 高碳热轧钢板的制造方法
CN112322995B (zh) 低屈强比高韧性tmcp型桥梁钢板及其生产方法
EP1444371B1 (de) In-line-verfahren zum rekristallisieren von erstarrten grobbändern in unlegiertem stahl und niedrig legiertem stahl
JP2004526862A5 (de)
US20100319812A1 (en) Method for producing a surface-decarburised hot-rolled strip
JP4300793B2 (ja) 材質均一性に優れた熱延鋼板および溶融めっき鋼板の製造方法
EP3722449B1 (de) Warmgewalztes stahlblech für gewickelte rohre und verfahren zu dessen herstellung
JP2512650B2 (ja) 材質と表面品質の優れたＣｒ−Ｎｉ系ステンレス鋼薄板の製造方法
KR101746994B1 (ko) 굽힘성 및 용접성이 우수한 열연도금강판 및 그 제조방법
JPS63145718A (ja) 加工性の優れた超高強度冷延鋼板の製造方法
JP2526122B2 (ja) ストリツプキヤステイングによる深絞り成形用冷延鋼板の製造方法
JPH0639676B2 (ja) 高強度溶融亜鉛めっき鋼板の製造方法

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: 20040519

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

RTI1 Title (correction)

Free format text: IN-LINE PROCESS FOR THE RECRYSTALLIZATION OF SOLIDIFIED COARSE STRIPS IN CARBON STEEL AND IN LOW-ALLOYED STEEL

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR

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

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050413

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: CH

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: LI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050413

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 60203733

Country of ref document: DE

Date of ref document: 20050519

Kind code of ref document: P

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

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050713

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050713

Ref country code: DK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050713

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050724

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

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

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20050913

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20051115

Ref country code: IE

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

Effective date: 20051115

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

Ref country code: MC

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

Effective date: 20051130

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

ET Fr: translation filed
26N No opposition filed

Effective date: 20060116

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A

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

Ref country code: DE

Payment date: 20081211

Year of fee payment: 7

Ref country code: LU

Payment date: 20081128

Year of fee payment: 7

Ref country code: NL

Payment date: 20081127

Year of fee payment: 7

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

Ref country code: AT

Payment date: 20081128

Year of fee payment: 7

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

Ref country code: SE

Payment date: 20081222

Year of fee payment: 7

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

Ref country code: FR

Payment date: 20081126

Year of fee payment: 7

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

Ref country code: GB

Payment date: 20081216

Year of fee payment: 7

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

Ref country code: BE

Payment date: 20090130

Year of fee payment: 7

BERE Be: lapsed

Owner name: *THYSSENKRUPP ACCIAI SPECIALI TERNI S.P.A.

Effective date: 20091130

REG Reference to a national code

Ref country code: NL

Ref legal event code: V1

Effective date: 20100601

EUG Se: european patent has lapsed
GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20091115

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20100730

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

Ref country code: AT

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

Effective date: 20091115

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: 20091130

Ref country code: FR

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

Effective date: 20091130

Ref country code: NL

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

Effective date: 20100601

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

Ref country code: DE

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

Effective date: 20100601

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: 20091115

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: 20091115

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: 20091116