EP1169486B1 - Verfahren zum erzeugen eines warmbandes - Google Patents
Verfahren zum erzeugen eines warmbandes Download PDFInfo
- Publication number
- EP1169486B1 EP1169486B1 EP00906372A EP00906372A EP1169486B1 EP 1169486 B1 EP1169486 B1 EP 1169486B1 EP 00906372 A EP00906372 A EP 00906372A EP 00906372 A EP00906372 A EP 00906372A EP 1169486 B1 EP1169486 B1 EP 1169486B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cooling
- hot strip
- cooled
- temperature
- phase
- 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.)
- Revoked
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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
- C21D8/0221—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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/46—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling metal immediately subsequent to continuous casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
- B21B37/76—Cooling control on the run-out table
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/54—Furnaces for treating strips or wire
- C21D9/56—Continuous furnaces for strip or wire
- C21D9/573—Continuous furnaces for strip or wire with cooling
Definitions
- the invention relates to a method for generating a Steel hot strip, in which the hot strip after the Finishing rolling a carried out in several stages Cooling is subjected.
- the structure can be cooled as such and the proportions of the individual structure types influence this structure. So it is possible through cooling, for example, strength, toughness and To influence the hardness of a hot strip.
- JP 10-195588 A discloses a method for producing a hot strip from a slab, which (in% by weight) 0.02-0.2% C, 0.1-1, 5% Si, 0.5-3.0% Mn and one or more of the elements Cr and Mo each with 0.1-2.0%, the rest iron.
- the hot strip is hot-rolled according to the known method at a final temperature corresponding at least to the Ar 3 temperature to thicknesses which are typically in the range from 0.8 to 1.4 mm.
- the hot strips are continuously cooled in a first stage that begins 0.1 to 5 s after hot rolling with a cooling rate in the temperature range of 680 - 720 ° C that is more than 50 ° C.
- the first stage of cooling is followed by an intermediate cooling phase, during which the belt cools in air for up to 15 seconds.
- a third cooling phase then follows, in which cooling is carried out at a cooling rate of at least 30 ° C./s in a temperature range from 300 to 600 ° C. Finally the tape is coiled.
- a comparable method is known from EP-A-0 719 868 known.
- a Slab with (in% by weight) 0.001 - 0.1% C, ⁇ 1.5% Si, 0.5 - 3.0% Mn, 0.01-0.1% Al, and one or more of the Elements P (0.05 - 0.15%) and Cr (0.5 - 1.5%), the rest Iron, at a hot rolling end temperature of up to 850 ° C continuously rolled into hot strip.
- Within A first is carried out 0.5 s after the finish hot rolling Cooling down at temperatures between 650 - 750 ° C lie.
- the cooling rate is at least 30 ° C / s, typically 42 - 70 ° C / s.
- the first cooling stage is followed by an intermediate cooling phase at which the belt cools in air for 4 to 60 seconds. This is followed by a third cooling at cooling rates of at least 30 ° C / s to between 100 ° C and 500 ° C lying reel temperature.
- the object of the invention is to provide a method create with which hot strips can be produced which have high formability and increased strength exhibit.
- the hot strip is cooled also in at least two consecutive through stages.
- the hot strip is in the the first cooling phase cooled much faster than the State of the art.
- This compact cooling during the first cooling phase has the consequence that the ⁇ / ⁇ conversion of effective and targeted in the ⁇ -region of hot-rolled strip is suppressed towards lower temperatures.
- the tape is then accelerated to the cooling brought desired final temperature.
- the hardness-increasing second phases of the hot strip structure like martensite, bainite and residual austenite, set. (At the end of the second cooling phase accelerated cooling can reach the final temperature of course, depending on the desired processing results required Act reel temperature.)
- the hot strip Steel optionally contain additional elements.
- the proportion (in mass%) of Cu, Ni, Mo not more than 0.8%, that of N, Ti, Nb, V, Zn, B not larger than 0.5%, that of P not larger than 0.09%, that of Cr not greater than 1.5% and that of S should not be greater than 0.02%.
- the method according to the invention is firstly for generating suitable for hot strips, which are based on steels are manufactured with low carbon contents. So is an advantageous variant of the invention Process characterized in that the steel (in Mass%) not more than 0.07% C, not more than 0.2% Si, not more than 0.6% Mn and not more than 0.08% Al contains the hot strip during finish rolling in Austenite area is rolled, the hot strip in the first Cooling phase of accelerated cooling starting from one Temperature above 850 ° C to a temperature of 680 is cooled to 750 ° C, the hot strip in the second Cooling phase accelerated cooling to a temperature of is cooled to less than 600 ° C and finally coiled becomes.
- the method of manufacture according to the invention is likewise suitable for DP hot strip steels.
- a corresponding one Design of the method according to the invention characterized in that the steel (in mass%) 0.04 - 0.09% C, not more than 0.2% Si, 0.5 - 2.0% Mn, 0.02 - Contains 0.09% P and not more than 0.9% Cr, and that the Hot strip after finish rolling in the first cooling phase accelerated cooling based on a temperature above 800 ° C to a temperature of 650 to 730 ° C is cooled that the hot strip in the second cooling phase accelerated cooling cooled to less than 500 ° C and that the hot strip is then coiled.
- a hot strip which on a steel with (in mass%) 0.25 - 1.05% C, not more than 0.25% Si and not more than 0.6% Mn based, after finishing rolling in the first cooling phase accelerated cooling based on a temperature above 800 ° C to a temperature of 530 to 620 ° C cooled, in the second cooling phase accelerated cooling cooled to less than 500 ° C and then coiled.
- a hot strip produced in this way has also improved hardness and better Forming properties compared to conventionally produced Tapes.
- the method is characterized in that the steel (in Mass%) 0.04 - 0.09% C, 0.5 - 1.5% Si, 0.5 - 2.0% Mn, 0.4 - 2.5% Al, no more than 0.09% P and no more than 0.9% Cr contains that the hot strip after Finishing rolls accelerated in the first cooling phase Cooling from a temperature above 800 ° C is cooled to a temperature of 650 to 730 ° C that the hot strip accelerated in the second cooling phase Cooling is cooled to less than 500 ° C and that Hot strip is then coiled.
- Such one Hot strip has DP and TRIP properties.
- a structural steel with an increased ferrite content and from it The following particularly good formability can be thereby make the steel (in mass%) 0.07 - 0.22% C, 0.1 - 0.45% Si and 0.2 - 1.5% Mn contains that the Hot strip after finish rolling in the first cooling phase accelerated cooling based on a temperature above 800 ° C to a temperature of 650 to 730 ° C is cooled that the hot strip in the second cooling phase accelerated cooling cooled to less than 500 ° C and that the hot strip is then coiled.
- a hot strip can be made with the same steel composition with improved hardness, on the other hand, that the hot strip after finish rolling in the first Cooling phase of accelerated cooling starting from one Temperature above 800 ° C to a temperature of 580 is cooled to 650 ° C that the hot strip in the second Cooling phase of accelerated cooling to less than 500 ° C is cooled and that the hot strip is then coiled becomes.
- the hot strip cooled in this way has one reduced ferrite content, higher bainite and martensite contents on.
- the Invention passes through the hot strip between the first Cooling phase and the second cooling phase accelerated Cooling an intermediate cooling phase during which the hot strip is exposed to air cooling.
- This intermediate cooling phase should take at least a second.
- in the cooling in air takes place the austenite transformation in ferrite faster and reaches one larger scope than in the prior art, wherein at the same time a strong grain-refining effect watch is.
- the procedure according to the invention can produce a hot strip, which compared to a conventional one Process in two laminar cooling stages with intermediate cooling in air-cooled hot strip same composition an increased hardness and a has a finer grain structure.
- the tape produced by the method according to the invention high strength and, unlike that after known methods produced tapes, a good one Formability on.
- the first cooling phase therefore begins at the latest two Seconds after the last pass of finish rolling.
- a further advantageous embodiment of the method, with which a hot strip of particularly good formability can be produced is characterized in that at least one of the rolling passes is carried out during the finish rolling in the austenite region below a temperature of Ar 3 + 80 ° C and that the total pass decrease during of finish rolling is more than 30%.
- the hot strip used steel expedient if the in particular as a thin slab primary material steel introduced into the respective rolling mill in the liquid phase with Ca or Ca carrier alloys is treated.
- the hot strip in the second cooling phase with a cooling rate of is cooled at least 30 ° C / s.
- Line 1 for producing a hot strip W comprises one Relay of several finishing stands, one of which is here only the last frame 2 is shown. In the Finishing rolling the hot strip W is on its The desired final thickness is rolled.
- a compact cooling device 3 is arranged.
- This Compact cooling device 3 includes not shown here Nozzles, via the cooling liquid, preferably water, under increased pressure on the top and bottom of the Hot strip W is brought.
- the volume flow of the Coolant is adjustable so that within the Compact cooling device 3 cooling speeds of 150 ° C / s to 1000 ° C / s can be achieved.
- the second cooling device 4 works kind of a conventional laminar cooling, in which the Coolant through several in the conveying direction F arranged one behind the other, also not shown here Fan is brought onto the hot strip W in a fan-like manner.
- the Number of nozzles acted upon and / or Volume flow in the area of the laminar cooling device 4 applied coolant can be regulated in such a way that in the area of the laminar cooling device 4 Cooling speeds of 30 to 150 ° C / s reached become.
- a reel device 5 In the conveying direction F of the belt behind the laminar cooling device 4 is a reel device 5 arranged, in which the hot strip W to a coil is wrapped.
- Hot strip W is used exclusively in the finishing mill in the austenite area with a total decrease of more rolled as 30%. If necessary, the hot strip W during the rolling of a thermomechanical treatment subjected.
- the hot strip W After the hot strip W has left the last stand 2 of the finished rolling mill, it arrives in the compact cooling device 3 within a transfer phase t 2 , which is shorter than two seconds.
- the hot strip W Upon entering the compact cooling device 3, the hot strip W becomes a first cooling phase t CK continuously exposed to a compact cooling, during which the hot strip W is cooled from an inlet temperature ET CK to an outlet temperature AT CK .
- the cooling rates achieved are between 250 and 1000 ° C / s.
- the ⁇ / ⁇ conversion of the hot strip steel is suppressed by the accelerated cooling of the hot strip W in the compact cooling device 3 within a short time t z after the exit from the finished rolling stack.
- the hot strip W then runs through a free stretch in which it is cooled in air for an intermediate cooling phase t PAUSE .
- the duration of the intermediate cooling phase t PAUSE is at least one second. During this time there is a partial conversion of the hot strip steel.
- the hot strip W arrives in the laminar cooling device 4. In this, it is cooled from an inlet temperature ET LK to an outlet temperature AT LK within a second cooling phase t LK .
- the set cooling rate is between 30 and 150 ° C / s.
- second phases bainite, martensite or residual austenite
- the excretion state of the hot strip W is also controlled in this way.
- Table 1 compares the structure components and the hardness of hot strips produced from steels "Stahl” - “Stahl2", which were produced according to the method according to the invention explained above, with the structure components and the hardness of hot strips of the same composition, which are produced in a conventional manner have been cooled in air in two laminar cooling devices with intervening cooling.
- Fig. 3 is for the steel in a solid line the course CLK of that structural change, which occurs when a hot strip is first in the manner according to the invention for the time t CK a compact cooling with a cooling rate of 250 ° C / s, then one Intermediate cooling phase t PAUSE and finally a laminar cooling cycle for the time t LK , contrasted with the LLK course of the structural transformation drawn in dashed lines, which occurs in a conventional combination of two laminar cooling systems with intermediate cooling in air.
- Table 1 confirms the statement in FIG. 3.
- Table 1 confirms the statement in FIG. 3.
- Table 1 confirms the statement in FIG. 3.
- those manufactured according to the invention Sample a structure with a finer grain structure than that generated by the conventional method. This has to Consequence that the hot strips produced according to the invention a good one despite the increased shares of the hard phases Show formability. This fact has been confirmed also for a TRIP steel ((in mass%) C: 0.2%, Al: 1.8 %, Mn: 1.6%).
- Such steel pointed to conventional Production method an average ferrite grain diameter from 6 - 7 ⁇ m. With the procedure according to the invention this diameter is reduced to less than 3 ⁇ m.
Description
C | 0,001 - 1,05 %, |
Si | ≤ 1,5 %, |
Mn | 0,05 - 3,5 %, |
Al | ≤ 2,5 %, |
- Cu, Ni, Mo mit einem Anteil ≤ 0,8 %,
- N, Ti, Nb, V, Zn, B mit einem Anteil ≤ 0,5 %,
- P mit einem Anteil ≤ 0,09 %,
- Cr mit einem Anteil ≤ 1,5 % und / oder
- S mit einem Anteil ≤ 0,02 %,
- Kontinuierliches Fertigwalzen des Warmbandes (W),
- kontinuierliches Abkühlen des Warmbandes (W) in mindestens zwei aufeinander folgenden Kühlphasen (tCK, tLK) beschleunigter Kühlung auf eine Endtemperatur,
- wobei die erste Kühlphase (tCK) beschleunigter Kühlung spätestens drei Sekunden nach dem letzten Walzstich des Fertigwalzens beginnt und
- wobei das Warmband (W) während der ersten Kühlphase (tCK) beschleunigter Kühlung mit einer Abkühlgeschwindigkeit von mindestens 250 °C/s gekühlt wird.
- Fig. 1
- den eine Kühlstrecke umfassenden Endabschnitt einer Linie zum Herstellen von Warmbändern in seitlicher Ansicht;
- Fig. 2
- ein Diagramm, in welchem der Temperaturverlauf während des Abkühlens innerhalb der Kühlstrecke dargestellt ist;
- Fig. 3
- ein Diagramm, in welchem die umgewandelten Anteile eines zur Herstellung eines Warmbandes verwendeten Stahls über der Temperatur bei herkömmlicher und bei erfindungsgemäßer Verfahrensweise dargestellt sind.
C | Mn | P | S | Si | Cu | Al | N | Cr | Ni | Ti | Nb | |
Stahl1 | 0,15 | 1,38 | 0,009 | 0,007 | 0.42 | 0,01 | 0,026 | 0,0041 | 0,02 | 0,02 | 0,02 | 0,018 |
Stahl2 | 0,13 | 1,45 | 0,012 | 0,004 | 0,35 | 0,14 | 0,037 | 0,0064 | 0,04 | 0,16 | 0,034 |
- F
- Förderrichtung,
- W
- Warmband,
- 1
- Linie zum Herstellen eines Warmbands,
- 2
- Fertigwalz-Gerüst,
- 3
- Compakt-Kühleinrichtung,
- 4
- Laminar-Kühleinrichtung,
- 5
- Haspeleinrichtung,
- t2
- Überführungsphase zwischen dem Austritt aus dem Fertigwalz-Gerüst 2 und dem Beginn der Compaktkühlung,
- tCK
- erste Kühlphase, welche das Warmband W benötigt, um die Länge der Compakt-Kühleinrichtung 3 zurückzulegen,
- ETCK
- Eingangstemperatur des Warmbandes W beim Eintritt in die Compakt-Kühleinrichtung 3,
- ATCK
- Austrittstemperatur des Warmbandes W beim Austritt aus der Compakt-Kühleinrichtung 3,
- tPAUSE
- Zwischenkühlphase, während der das Warmband W an Luft gekühlt wird,
- tLK
- zweite Kühlphase, in der das Warmband W in der Laminar-Kühleinrichtung 4 abgekühlt wird,
- ETLK
- Eingangstemperatur des Warmbandes W beim Eintritt in die Laminar-Kühleinrichtung 4,
- ATLK
- Austrittstemperatur des Warmbandes W beim Austritt aus der Laminar-Kühleinrichtung 4,
- CLK
- Verlauf der Gefügeumwandlung, der sich einstellt, wenn ein Warmband zunächst eine Compakt-Kühlung und anschließend eine Laminar-Kühlung durchläuft,
- LLK
- Verlauf LLK der Gefügeumwandlung, der sich bei einer Kombination zweier Laminar-Kühlungen einstellt,
- UA
- jeweiliger umgewandelter Anteil des Austenits.
Claims (14)
- Verfahren zum Erzeugen eines Warmbandes (W), welches insbesondere aus Strangguß in Form von wiedererwärmten oder direkt aus der Gießhitze eingesetzten Brammen, aus Dünnbrammen oder aus gegossenem Band basierend auf einem Stahl hergestellt ist, der (in Masse-%)
C 0,001 - 1,05 %, Si ≤ 1,5 %, Mn 0,05 - 3,5 %, Al ≤ 2,5 %, Cu, Ni, Mo mit einem Anteil ≤ 0,8 %,N, Ti, Nb, V, Zn, B mit einem Anteil ≤ 0,5 %,P mit einem Anteil ≤ 0,09 %,Cr mit einem Anteil ≤ 1,5 % und / oderS mit einem Anteil ≤ 0,02 %,
als Rest Eisen sowie übliche Begleitelemente enthält,
wobei der Stahl ebenso wahlweise in der Flüssigphase mit Ca oder Ca-Trägerlegierungen behandelt sein kann,
umfassend die folgenden Schritte:Kontinuierliches Fertigwalzen des Warmbandes (W),kontinuierliches Abkühlen des Warmbandes (W) in mindestens zwei aufeinander folgenden Kühlphasen (tCK,tLK) beschleunigter Kühlung auf eine Endtemperatur,wobei die erste Kühlphase (tCK) beschleunigter Kühlung spätestens drei Sekunden nach dem letzten Walzstich des Fertigwalzens beginnt undwobei das Warmband (W) während der ersten Kühlphase (tCK) beschleunigter Kühlung mit einer Abkühlgeschwindigkeit von mindestens 250 °C/s gekühlt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Stahl 0,005 bis 0,4 Masse-% Silizium enthält.
- Verfahren nach Anspruch 1, dadurch gekennzeichnet,daß der Stahl (in Masse-%)
C ≤ 0,07 %, Si ≤ 0,2 %, Mn ≤ 0,6 %, Al ≤ 0,08 % daß das Warmband (W) während des Fertigwalzens im Austenitgebiet gewalzt wird,daß das Warmband (W) in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 850 °C auf eine Temperatur von 680 bis 750 °C gekühlt wird,daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf eine Temperatur von weniger als 600 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Stahl (in Masse-%)
C 0,04 - 0,09 %, Si ≤ 0,2 %, Mn 0,5 - 2,0 %, P 0,02 - 0,09 %, Cr ≤ 0,9 % daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 800 °C auf eine Temperatur von 650 bis 730 °C gekühlt wird,daß das Warmband (W) in der zweiten Kühlphase beschleunigter Kühlung (tLK) auf weniger als 500 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach einem der Ansprüche 1, dadurch gekennzeichnet, daß der Stahl (in Masse-%)
C 0,25 - 1,05 %, Si ≤ 0,25 %, Mn ≤ 0,6 % daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 800 °C auf eine Temperatur von 530 bis 620 °C gekühlt wird,daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf weniger als 500 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Stahl (in Masse-%)
C 0,12 - 0,3 %, Mn 1,2 - 3,5 %, Al 1,1 - 2,2 % daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur, welche zwischen der Ar3-Temperatur und einer Temperatur von Ar3 + 150 °C liegt, auf eine Temperatur gekühlt wird, welche bis zu 50 °C unterhalb der Ar3-Temperatur liegt,daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf 350 bis 550 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet,daß der Stahl (in Masse-%)
C 0,04 - 0,09 %, Si 0,5 - 1,5 %, Mn 0,5 - 2,0 %, Al 0,4 - 2,5 %, P ≤ 0,09 %, Cr ≤ 0,9 %, daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 800 °C auf eine Temperatur von 650 bis 730 °C gekühlt wird,daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf weniger als 500 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet,d a ß der Stahl (in Masse-%)
C 0,07 - 0,22 %, Si 0,1 - 0,45 %, Mn 0,2 - 1,5 %, daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 800 °C auf eine Temperatur von 650 bis 730 °C gekühlt wird,daß das Warmband in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf weniger als 500 °C gekühlt wird unddaß das Warmband anschließend gehaspelt wird. - Verfahren nach Anspruch 1, dadurch gekennzeichnet,daß der Stahl (in Masse-%)
C 0,07 - 0,22 %, Si 0,1 - 0,45 %, Mn 0,2 - 1,5 %, daß das Warmband (W) nach dem Fertigwalzen in der ersten Kühlphase (tCK) beschleunigter Kühlung ausgehend von einer Temperatur oberhalb 800 °C auf eine Temperatur von 580 bis 650 °C gekühlt wird,daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung auf weniger als 500 °C gekühlt wird unddaß das Warmband (W) anschließend gehaspelt wird. - Verfahren nach einem der voranstehenden Ansprüche, dadurch gekennzeichnet, daß das Warmband (W) zwischen der ersten Kühlphase (tCK) beschleunigter Kühlung und der zweiten Kühlphase (tLK) beschleunigter Kühlung eine Zwischenkühlphase (tPAUSE) durchläuft, während der das Warmband (W) einer Luftkühlung ausgesetzt ist.
- Verfahren nach Anspruch 10, dadurch gekennzeichnet, daß die Zwischenkühlphase (tPAUSE) mindestens eine Sekunde lang dauert.
- Verfahren nach einem der voranstehenden Ansprüche dadurch gekennzeichnet, daß die erste Kühlphase (tCK) beschleunigter Kühlung spätestens zwei Sekunden nach dem letzten Walzstich des Fertigwalzens beginnt.
- Verfahren nach einem der voranstehenden Ansprüche, dadurch gekennzeichnet, daß mindestens einer der Walzstiche während des Fertigwalzens im Austenitgebiet unterhalb einer Temperatur von Ar3 + 80 °C durchgeführt und eine Gesamtstichabnahme von mehr als 30% erreicht wird.
- Verfahren nach einem der voranstehenden Ansprüche, dadurch gekennzeichnet, daß das Warmband (W) in der zweiten Kühlphase (tLK) beschleunigter Kühlung mit einer Abkühlgeschwindigkeit von mindestens 30 °C/s gekühlt wird.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19911287A DE19911287C1 (de) | 1999-03-13 | 1999-03-13 | Verfahren zum Erzeugen eines Warmbandes |
DE19911287 | 1999-03-13 | ||
PCT/EP2000/001517 WO2000055381A1 (de) | 1999-03-13 | 2000-02-24 | Verfahren zum erzeugen eines warmbandes |
Publications (2)
Publication Number | Publication Date |
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EP1169486A1 EP1169486A1 (de) | 2002-01-09 |
EP1169486B1 true EP1169486B1 (de) | 2003-05-02 |
Family
ID=7900901
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP00906372A Revoked EP1169486B1 (de) | 1999-03-13 | 2000-02-24 | Verfahren zum erzeugen eines warmbandes |
Country Status (7)
Country | Link |
---|---|
US (1) | US6855218B1 (de) |
EP (1) | EP1169486B1 (de) |
JP (1) | JP2002539330A (de) |
AT (1) | ATE239097T1 (de) |
DE (2) | DE19911287C1 (de) |
ES (1) | ES2195867T3 (de) |
WO (1) | WO2000055381A1 (de) |
Families Citing this family (30)
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DE60045303D1 (de) * | 1999-09-29 | 2011-01-13 | Jfe Steel Corp | Stahlblech und verfahren zu dessen herstellung |
DE10161465C1 (de) * | 2001-12-13 | 2003-02-13 | Thyssenkrupp Stahl Ag | Verfahren zum Herstellen von Warmband |
DE50205631D1 (de) * | 2002-09-11 | 2006-04-06 | Thyssenkrupp Stahl Ag | Ferritisch/martensitischer Stahl mit hoher Festigkeit und sehr feinem Gefüge |
JP4470701B2 (ja) * | 2004-01-29 | 2010-06-02 | Jfeスチール株式会社 | 加工性および表面性状に優れた高強度薄鋼板およびその製造方法 |
DE102004038159B3 (de) * | 2004-08-06 | 2006-05-18 | Ab Skf | Verfahren zur Wärmebehandlung von Werkstücken aus Stahl oder Gusseisen |
DE102005003551B4 (de) * | 2005-01-26 | 2015-01-22 | Volkswagen Ag | Verfahren zur Warmumformung und Härtung eines Stahlblechs |
US9149868B2 (en) * | 2005-10-20 | 2015-10-06 | Nucor Corporation | Thin cast strip product with microalloy additions, and method for making the same |
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 |
DE102005051052A1 (de) * | 2005-10-25 | 2007-04-26 | Sms Demag Ag | Verfahren zur Herstellung von Warmband mit Mehrphasengefüge |
DE102005052069B4 (de) * | 2005-10-28 | 2015-07-09 | Saarstahl Ag | Verfahren zum Herstellen von Vormaterial aus Stahl durch Warmverformen |
US7471442B2 (en) * | 2006-06-15 | 2008-12-30 | Qualcomm Mems Technologies, Inc. | Method and apparatus for low range bit depth enhancements for MEMS display architectures |
US8333923B2 (en) * | 2007-02-28 | 2012-12-18 | Caterpillar Inc. | High strength gray cast iron |
JP5214905B2 (ja) * | 2007-04-17 | 2013-06-19 | 株式会社中山製鋼所 | 高強度熱延鋼板およびその製造方法 |
JP5176431B2 (ja) | 2007-08-24 | 2013-04-03 | Jfeスチール株式会社 | 高強度熱延鋼板の製造方法 |
US20090301613A1 (en) * | 2007-08-30 | 2009-12-10 | Jayoung Koo | Low Yield Ratio Dual Phase Steel Linepipe with Superior Strain Aging Resistance |
DE102008004371A1 (de) * | 2008-01-15 | 2009-07-16 | Robert Bosch Gmbh | Bauelement, insbesondere eine Kraftfahrzeugkomponente, aus einem Dualphasen-Stahl |
WO2011100798A1 (en) | 2010-02-20 | 2011-08-25 | Bluescope Steel Limited | Nitriding of niobium steel and product made thereby |
JP5423737B2 (ja) * | 2010-08-10 | 2014-02-19 | Jfeスチール株式会社 | 加工性に優れた高強度熱延鋼板およびその製造方法 |
FI123847B (fi) * | 2011-06-15 | 2013-11-15 | Rautaruukki Oyj | Menetelmä keskihiilisen terästuotteen valmistamiseksi ja kuumavalssattu keskihiilinen terästuote |
CN104603297A (zh) * | 2012-07-30 | 2015-05-06 | 塔塔钢铁荷兰科技有限责任公司 | 用于制备碳钢钢带材的方法 |
DE102013019698A1 (de) * | 2013-05-03 | 2014-11-06 | Sms Siemag Ag | Verfahren zur Herstellung eines metallischen Bandes |
JP6778943B2 (ja) | 2014-12-19 | 2020-11-04 | ニューコア・コーポレーション | 熱間圧延軽量マルテンサイト鋼板及びその製造方法 |
CN107828951B (zh) * | 2017-10-16 | 2019-12-03 | 首钢京唐钢铁联合有限责任公司 | 一种制造冷轧高强钢的方法及装置 |
CN112981229A (zh) * | 2021-01-20 | 2021-06-18 | 江阴兴澄特种钢铁有限公司 | 一种耐高温细晶空心传动半轴用中碳圆钢及其制造方法 |
CN113198843A (zh) * | 2021-04-25 | 2021-08-03 | 湖南华菱湘潭钢铁有限公司 | 一种高Si弹簧圆钢的生产方法 |
CN113231485B (zh) * | 2021-05-07 | 2022-01-28 | 西安钢研功能材料股份有限公司 | 一种高膨胀合金无焊缝大卷重带材的制备方法 |
AT525283B1 (de) * | 2021-10-29 | 2023-02-15 | Primetals Technologies Austria GmbH | Verfahren zur Herstellung eines Dualphasenstahlbands in einer Gieß-Walz-Verbundanlage, ein mit dem Verfahren hergestelltes Dualphasenstahlband und eine Gieß-Walz-Verbundanlage |
CN113999961A (zh) * | 2021-11-02 | 2022-02-01 | 攀钢集团攀枝花钢铁研究院有限公司 | 改善带钢心部带状组织的生产方法 |
CN115198171A (zh) * | 2022-06-08 | 2022-10-18 | 南京钢铁股份有限公司 | 一种低密度轴承钢及其冶炼方法 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS572840A (en) * | 1980-06-06 | 1982-01-08 | Nippon Steel Corp | Production of high strength low yield ratio high ductility composite structure steel plate of high artificial aging hardness after working |
JPS57137426A (en) | 1981-02-20 | 1982-08-25 | Kawasaki Steel Corp | Production of low yield ratio, high tensile hot rolled steel plate by mixed structure |
JP3039842B2 (ja) | 1994-12-26 | 2000-05-08 | 川崎製鉄株式会社 | 耐衝撃性に優れる自動車用熱延鋼板および冷延鋼板ならびにそれらの製造方法 |
JPH09241790A (ja) | 1996-03-07 | 1997-09-16 | Nippon Steel Corp | 熱延連続化プロセスによる耐久疲労性に優れた低降伏比型熱延高強度鋼板およびその製造方法 |
BE1010142A6 (fr) | 1996-04-16 | 1998-01-06 | Centre Rech Metallurgique | Procede pour la fabrication d'une bande laminee a chaud en acier a haute resistance. |
JP3253880B2 (ja) | 1996-12-27 | 2002-02-04 | 川崎製鉄株式会社 | 成形性と耐衝突特性に優れる熱延高張力鋼板およびその製造方法 |
-
1999
- 1999-03-13 DE DE19911287A patent/DE19911287C1/de not_active Expired - Fee Related
-
2000
- 2000-02-24 JP JP2000605797A patent/JP2002539330A/ja active Pending
- 2000-02-24 US US09/936,381 patent/US6855218B1/en not_active Expired - Lifetime
- 2000-02-24 AT AT00906372T patent/ATE239097T1/de not_active IP Right Cessation
- 2000-02-24 WO PCT/EP2000/001517 patent/WO2000055381A1/de not_active Application Discontinuation
- 2000-02-24 EP EP00906372A patent/EP1169486B1/de not_active Revoked
- 2000-02-24 ES ES00906372T patent/ES2195867T3/es not_active Expired - Lifetime
- 2000-02-24 DE DE50001976T patent/DE50001976D1/de not_active Revoked
Also Published As
Publication number | Publication date |
---|---|
DE50001976D1 (de) | 2003-06-05 |
US6855218B1 (en) | 2005-02-15 |
WO2000055381A1 (de) | 2000-09-21 |
ES2195867T3 (es) | 2003-12-16 |
DE19911287C1 (de) | 2000-08-31 |
EP1169486A1 (de) | 2002-01-09 |
ATE239097T1 (de) | 2003-05-15 |
JP2002539330A (ja) | 2002-11-19 |
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