EP2604715B1 - Procédé de fabrication d'une tôle d'acier laminée à froid à haute résistance ayant une excellente formabilité et résistance à l'impact - Google Patents

Procédé de fabrication d'une tôle d'acier laminée à froid à haute résistance ayant une excellente formabilité et résistance à l'impact Download PDF

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EP2604715B1
EP2604715B1 EP10855912.1A EP10855912A EP2604715B1 EP 2604715 B1 EP2604715 B1 EP 2604715B1 EP 10855912 A EP10855912 A EP 10855912A EP 2604715 B1 EP2604715 B1 EP 2604715B1
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Prior art keywords
temperature
steel sheet
martensite
rolling
rolled steel
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German (de)
English (en)
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EP2604715A1 (fr
EP2604715A4 (fr
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Tatsuya Nakagaito
Saiji Matsuoka
Shinjiro Kaneko
Yoshiyasu Kawasaki
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JFE Steel Corp
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JFE Steel Corp
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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
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • 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
    • C21D1/25—Hardening, combined with annealing between 300 degrees Celsius and 600 degrees Celsius, i.e. heat refining ("Vergüten")
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • 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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • 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
    • C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
    • 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
    • C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
    • 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
    • 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
    • C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • 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
    • C21D2211/001—Austenite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/02—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for springs

Definitions

  • the present invention relates to a method for manufacturing a high-strength cold rolled steel sheet having excellent formability for use in structural parts and suspension parts mainly used in the automobile industry field.
  • DP steel ferrite-martensite dual phase steel
  • TRIP steel that utilizes the transformation-induced plasticity of retained austenite
  • Patent Literature 1 discloses a method for manufacturing a high-strength steel sheet having good formability, with which high ductility is achieved by adding large quantities of Si and thereby reliably obtaining retained austenite.
  • the stretch flangeability is an indicator of formability during flange-forming through expanding holes already made, and is a property as important as the elongation property required for high-strength steel sheets.
  • Patent Literature 2 discloses a method for manufacturing a cold rolled steel sheet having good stretch flangeability with which the stretch flangeability is improved by forming a ferrite-tempered martensite multi-phase microstructure by conducting quenching and tempering after annealing and soaking.
  • this technology although high stretch flangeability is achieved, the elongation is low.
  • PTL 3 describes a method for manufacturing a high tensile strength galvanized steel sheet with excellent formability, comprising the steps of subjecting a slab having an elemental composition comprising, in terms of % by mass, 0.05 to 0.3 % of C, 0.01 to 2.5 % of Si, 0.5 to 3.5 % of Mn, 0.003 to 0.100 % of P, 0.02 % or less of S, 0.010 to 1.5 % of Al and 0.007 % or less of N, the remainder being Fe and unavoidable impurities, to hot rolling and cold rolling thereby making a cold rolled steel sheet, subjecting the cold rolled steel sheet to annealing including steps of heating and maintaining the steel sheet in a temperature range from 750 to 950°C for 10 seconds or more, cooling the steel sheet from 750°C to a temperature range from (Ms point - 100°C) to (Ms point - 200°C) at an average cooling rate of 10°C/s or more, and reheating and maintaining the steel sheet in
  • PTL 4 describes a method for manufacturing a high-strength galvanized steel sheet with excellent formability, comprising the steps of hot rolling a slab that contains, in terms of % by mass, 0.05 to 0.3 % C, 0.01 to 2.5 % Si, 0.5 to 3.5 % of Mn, 0.003 to 0.100 % or less of P, 0.02 % or less of S and 0.010 to 1.5 % of Al, the total of Si and Al being 0.5 to 2.5 %, the remainder being iron and incidental impurities, to form a steel sheet; in continuous annealing, heating the steel sheet to a temperature in the range of 750 to 900°C at an average heating rate of at least 10°C/s in the temperature range of 500°C to an A 1 transformation point, holding that temperature for at least 10 seconds, cooling the steel sheet from 750°C to a temperature in the range of (Ms point - 100°C) to (Ms point - 200°C) at an average cooling rate of at least 10°C/s
  • the present invention has been made by addressing the problems described above and an object of the present invention is to provide a method for manufacturing a high-strength cold rolled steel sheet having excellent ductility and stretch flangeability.
  • the inventors of the invention of the present application have conducted extensive studies from the points of view of steel sheet composition and microstructure so as to address the problems described above and manufacture a high-strength cold rolled steel sheet having excellent ductility and stretch flangeability. As a result, they have found that when the steel has alloy elements adequately controlled, intensively cooled to a 150 to 350°C temperature range during cooling from the soaking temperature in the annealing process, and reheated, a microstructure containing 20% or more ferrite and 10 to 60% tempered martensite in terms of area ratio and 3 to 15% retained austenite in terms of volume ratio can be obtained and high ductility and stretch flangeability can be achieved.
  • the ductility improves due to a TRIP effect of the retained austenite.
  • the martensite generated by transformation of retained austenite under application of strain becomes very hard and as a result exhibits a hardness significantly different from that of the main phase ferrite, thereby degrading the stretch flangeability.
  • this steel sheet microstructure can exhibit high formability and improved crashworthiness.
  • the present invention provides a method for manufacturing a high-strength cold rolled steel sheet having excellent formability and crashworthiness, the method comprising hot-rolling and cold-rolling a slab having a composition comprising, on a mass% basis, C: 0.05 to 0.3%, Si: 0.3 to 2.5%, Mn: 0.5 to 3.5%, P: 0.003 to 0.100%, S: 0.02% or less, Al: 0.010 to 0.5%, optionally at least one element selected from Cr: 0.005 to 2.00%, Mo: 0.005 to 2.00%, V: 0.005 to 2.00%, Ni: 0.005 to 2.00%, and Cu: 0.005 to 2.00%, optionally one or both of Ti: 0.01 to 0.20% and Nb: 0.01 to 0.20%, optionally B: 0.0002 to 0.005%, optionally one or both of Ca: 0.001 to 0.005% and REM: 0.001 to 0.005%, and balance being iron and unavoidable impurities, to manufacture a cold rolled steel sheet and
  • the present invention a high-strength cold rolled steel sheet having excellent formability is obtained.
  • the present invention achieves advantageous effects such as realizing both weight reduction and improved crash safety of automobiles and greatly contributing to improving performance of automobile bodies.
  • Carbon (C) is an element that stabilizes austenite and promotes generation of phases other than ferrite. Thus, carbon is needed to increase the steel sheet strength, generate a multiphase structure, and improve the TS-EL balance. At a C content less than 0.05%, it is difficult to reliably obtain phases other than ferrite even when the production conditions are optimized and TS ⁇ EL decreases as a result. At a C content exceeding 0.3%, hardening of welded portions and heat-affected zones is significant, and mechanical properties of the welded portions are deteriorated. Thus, the C content is within the range of 0.05 to 0.3% and preferably 0.08 to 0.15%.
  • Silicon (Si) is an element effective for strengthening the steel. Silicon is also a ferrite-generating element, suppresses C from becoming concentrated and forming carbides in the austenite, and thus serves to accelerate generation of retained austenite.
  • the Si content is less than 0.3%, the effects of addition are low. Thus, the lower limit is 0.3%. Excessive addition deteriorates the surface quality and weldability. Thus, the Si content is 2.5% or less.
  • the Si content is preferably in the range of 0.7 to 2.0%.
  • Manganese (Mn) is an element effective for strengthening the steel and accelerates generation of low-temperature transformation-forming phase such as tempered martensite. Such an effect is observed at a Mn content of 0.5% or more. However, when the Mn content exceeds 3.5%, the second phase fraction increases excessively, the ductility deterioration of ferrite due to solid solution strengthening becomes significant, and formability is degraded. Accordingly, the Mn content is within the range of 0.5 to 3.5% and preferably in the range of 1.5 to 3.0%.
  • Phosphorus (P) is an element effective for strengthening the steel and this effect is achieved at a P content of 0.003% or more.
  • P content is in the range of 0.003% to 0.100%.
  • S Sulfur
  • the S content is preferably as low as possible but is limited to 0.02% or less from the production cost point of view.
  • Aluminum (Al) acts as a deoxidizing agent and is an element effective for cleanliness of the steel. Aluminum is preferably added in the deoxidizing process. When the Al content is less than 0.01%, the effect of addition is little and thus the lower limit is 0.01%. However, addition of large quantities of Al increases the risk of slab cracking during continuous casting and decreases the productivity. Thus, the upper limit of the Al content is 0.5%.
  • the high-strength cold rolled steel sheet manufactured by the method of the present invention contains the above-described components as the basic components and the balance is iron and unavoidable impurities. However, the following components can be adequately contained according to the desired properties.
  • Chromium (Cr), molybdenum (Mo), vanadium (V), nickel (Ni), and copper (Cu) suppress generation of pearlite during cooling from the annealing temperature, promote generation of low-temperature transformation-forming phases, and effectively serves to strengthen the steel.
  • Cr, Mo, V, Ni, and Cu are contained.
  • the content of each of Cr, Mo, V, Ni, and Cu exceeds 2.00%, the effect is saturated and the cost will rise.
  • the Cr, Mo, V, Ni, and Cu contents are each in the range of 0.005 to 2.00%.
  • Titanium (Ti) and niobium (Nb) form carbon nitrides and have an effect of strengthening the steel by precipitation. Such effects are observed at a content of 0.01% or more for each element.
  • Ti and Nb are contained in amounts exceeding 0.20%, excessive strengthening occurs and the ductility is decreased.
  • the Ti and Nb contents are each within the range of 0.01 to 0.20%.
  • B Boron
  • Ca Ca
  • REM rare earth element
  • the area fraction of the ferrite is less than 20%, TS ⁇ EL decreases.
  • the area fraction of ferrite is limited to 20% or more and preferably 50% or more.
  • Tempered martensite is a ferrite-cementite multiphase having a high dislocation density and is obtained by heating martensite to a temperature equal to or lower than Ac 1 transformation point and preferably to a temperature lower than Ac 1 transformation point. Tempered martensite effectively strengthens the steel.
  • the microstructure obtained by heating martensite to a temperature exceeding Ac 1 transformation point is a microstructure that does not contain cementite in ferrite and is fundamentally different from the tempered martensite intended in the present invention.
  • the tempered martensite Compared to martensite, the tempered martensite has less adverse effects on stretch flangeability and is a phase effective for reliably obtaining the strength without significantly decreasing the stretch flangeability.
  • the area fraction of the tempered martensite is less than 10%, it becomes difficult to reliably obtain the strength.
  • the area fraction exceeds 60%, TS ⁇ EL is decreased.
  • the area fraction of the martensite is limited to 10 to 60%.
  • Martensite effectively increases the strength of the steel but significantly decreases the stretch flangeability once the area fraction of the martensite exceeds 10%. Thus, the area fraction of the martensite is limited to 0 to 10%.
  • volume fraction of retained austenite 3 to 15%
  • Retained austenite not only contributes to strengthening of the steel but also effectively improves TS ⁇ EL of the steel. Such effects are achieved at a volume fraction of 3% or more. When the volume fraction of the retained austenite exceeds 15%, the stretch flangeability is decreased. Accordingly, the volume fraction of the retained austenite is limited to 3 to 15%.
  • Average crystal grain diameter of low-temperature transformation-forming phases constituted by martensite, tempered martensite, and retained austenite 3 ⁇ m or less
  • Low-temperature transformation-forming phases constituted by martensite, tempered martensite, and retained austenite effectively improve the crashworthiness.
  • finely dispersing the low-temperature transformation-forming phases improves the crashworthiness, and this effect becomes notable when the average crystal grain diameter of the low-temperature transformation-forming phases is 3 ⁇ m or less. Accordingly, the average crystal grain diameter of the low-temperature transformation-forming phases is limited to 3 ⁇ m or less.
  • the phases other than ferrite, tempered martensite, martensite, and retained austenite may include pearlite and bainite but such phases do not present problem as long as the above-described phase structure is satisfied.
  • the pearlite is preferably 3% or less from the view points of ductility and stretch flangeability.
  • a steel having a composition controlled as described above is melted in a converter or the like and formed into a slab by continuous casting or the like.
  • This steel is hot-rolled, cold-rolled, and continuously annealed.
  • the manufacturing methods regarding casting, hot-rolling, and cold-rolling are not particularly limited but preferable manufacturing methods are described below.
  • the steel slab used is preferably manufactured by continuous casting in order to prevent macrosegregation of the components but an ingot casting technique or a thin slab casting technique may be employed.
  • an energy-saving process such as hot direct rolling or direct rolling which involves sending the hot slab to a heating furnace without cooling the slab to room temperature or which involves rolling the slab immediately after a short period of heat retention may be employed without any difficulty.
  • the slab heating temperature is preferably low from the viewpoint of energy. At a heating temperature less than 1100°C, carbides cannot be sufficiently dissolved or the risks of troubles during hot-rolling increases due to an increased rolling load. In order to prevent the increase in scale loss attributable to oxidation weight gain, the slab heating temperature is preferably 1300°C or less.
  • a sheet bar heater that heats the sheet bar may be employed.
  • Finishing temperature Ar 3 transformation point or more.
  • the finishing temperature is less than the Ar 3 transformation point, ferrite and austenite are generated during rolling, and a band-like microstructure readily occurs in the steel sheet. Such a band-like microstructure remains after cold rolling and annealing, may generate anisotropy in the material properties, and may decrease the formability. Accordingly, the finishing temperature is preferably equal to or higher than Ar 3 transformation point.
  • the coiling temperature is preferably in the range of 450 to 700°C.
  • part or all of the finish rolling may be conducted by lubrication rolling.
  • Lubrication rolling is effective from the viewpoints of uniform steel sheet shape and material homogeneity.
  • the coefficient of friction during lubrication rolling is preferably in the range of 0.25 to 0.10.
  • Preferable is a continuous rolling process of joining sheet bars next to each other and continuously finish-rolling the sheet bars.
  • the continuous rolling process is also preferable from the viewpoint of operation stability of hot rolling.
  • the oxidized scales on the surface of the hot-rolled steel sheet are preferably removed by pickling and the steel sheet is cold-rolled to form a cold-rolled steel sheet having a particular thickness.
  • the pickling conditions and the cold rolling conditions are not particularly limited and typical conditions may be used.
  • the reduction of cold rolling is preferably 40% or more.
  • Average heating rate from 500°C to Ac 1 transformation point 10°C/s or more
  • the average heating rate in the recrystallization temperature zone, 500°C to Ac 1 transformation point, of the steel of the present invention is 10°C/s or more, recrystallization during heating is suppressed, austenite generated at Ac 1 transformation temperature or higher becomes finer, and the microstructure after annealing and cooling becomes finer.
  • the average grain diameter of the low-temperature transformation-forming phase can be reduced to 3 ⁇ m or less.
  • the average heating rate from 500°C to Ac 1 transformation point is limited to 10°C/s or more and more preferably 20°C/s or more.
  • the heating temperature is less than 750°C or the holding time is less than 10 seconds, generation of austenite during annealing is insufficient and a sufficient amount of low-temperature transformation-forming phases cannot be reliably obtained after annealing and cooling.
  • the upper limits of the holding temperature and the holding time are not particularly defined, the effects saturate and the cost will increase when the holding temperature is 900°C or more and the holding time is 600 seconds or more. Accordingly, the holding temperature is preferably less than 900°C and the holding time is preferably less than 600 seconds.
  • the cooling rate from 750°C is less than 10°C/s, pearlite is generated and TS ⁇ EL and stretch flangeability are degraded.
  • the cooling rate from 750°C is limited to 10°C/s or more.
  • the temperature condition of ending the cooling is one of the most crucial conditions of this technology. At the time cooling is stopped, part of austenite transforms into martensite and the rest forms untransformed austenite. When reheated, plated and alloyed, and cooled to room temperature, martensite turns into tempered martensite and untransformed austenite transforms into retained austenite or martensite.
  • controlling the temperature of ending the cooling determines the final area fractions of the martensite, the retained austenite, and the tempered martensite.
  • the temperature of ending the cooling is higher than 350°C, martensite transformation at the time cooling is stopped is insufficient and the amount of untransformed austenite is large, thereby ultimately generating excessive amounts of martensite or retained austenite and degrading the stretch flangeability.
  • the temperature of ending the cooling is lower than 150°C, most of austenite transforms into martensite during cooling, the amount of untransformed austenite decreases, and 3% or more of retained austenite is not obtained. Accordingly, the temperature of ending the cooling is set within the range of 150 to 350°C.
  • any cooling method such as gas jet cooling, mist cooling, water cooling, or metal quenching, may be employed as long as the target cooling rate and cooling end temperature are achieved.
  • the martensite generated during cooling is tempered and forms tempered martensite.
  • the stretch flangeability is improved, the untransformed austenite that did not transform into martensite during cooling is stabilized, and 3% or more of retained austenite is obtained at the final stage, thereby improving the ductility.
  • the reheating temperature is less than 350°C, the martensite is not sufficiently tempered and the austenite is not sufficiently stabilized, thereby degrading stretch flangeability and ductility. If the reheating temperature exceeds 600°C, untransformed austenite at the time cooling is stopped transforms into pearlite and 3% or more of retained austenite cannot be obtained at the final stage. Accordingly, the heating temperature is limited to 350 to 600°C.
  • the reheating temperature is set within the range of 350 to 600°C and the holding time within that temperature range is limited to 10 to 600 seconds.
  • the annealed steel sheet may be subjected to temper rolling to correct shape, adjust surface roughness, etc. Moreover, treatment such as resin or oil/fat coating and various other coating may be performed.
  • a steel having the composition shown in Table 1 and balance being Fe and unavoidable impurities was melted in a converter and continuously casted into a slab.
  • the slab is hot-rolled to a thickness of 3.0 mm.
  • the hot rolling conditions were as follows: finishing temperature: 900°C, cooling rate after rolling: 10°C/s, and coiling temperature: 600°C. Then the hot-rolled steel sheet was pickled and cold-rolled to a thickness of 1.2 mm to manufacture a cold rolled steel sheet.
  • the cold rolled steel sheet was annealed under the conditions described in Table 2 by using a continuous annealing line.
  • the cross-sectional microstructure of the steel sheet was observed by exposing the microstructure by using a 3% nital solution (3% nitric acid + ethanol), observing the position 1/4 of the thickness in the depth direction by using a scanning electron microscope, and conducting an image processing of a picture of the microstructure taken to determine the fraction of the ferrite phase (the image processing can be performed by using commercially available image processing software).
  • the area fractions of the martensite and tempered martensite were determined by taking SEM photographs of adequate magnification, e.g., about 1000 to 3000 magnification, depending on the fineness of the microstructure and then determining the quantity by using image processing software.
  • the average grain diameter of the low-temperature transformation-forming phase was determined by dividing the area of the low-temperature transformation-forming phases in the observed area by the number of the low-temperature transformation-forming phases, determining the average area therefrom, and raising the average to the power of 1/2.
  • the volume ratio of the retained austenite was determined by polishing the steel sheet to a surface 1/4 in the thickness direction and measuring X-ray diffraction intensity of the 1/4 thickness surface.
  • a MoK ⁇ line was used as the incident X ray, the intensity ratios were determined for all combinations of the integrated intensities of peaks of ⁇ 111 ⁇ , ⁇ 200 ⁇ , ⁇ 220 ⁇ , and ⁇ 311 ⁇ faces of the retained austenite phase and the ⁇ 110 ⁇ , ⁇ 200 ⁇ , and ⁇ 211 ⁇ faces of the ferrite phase, and the average value was assumed to be the volume fraction of the retained austenite.
  • the tensile property was determined by using a JIS No. 5 specimen sampled from the steel sheet in such a manner that the tensile direction was orthogonal to the rolling direction, conducting a tensile test according to JIS Z2241 to measure TS (tensile strength) and EL (elongation), and determining the strength-elongation balance value represented by the product of the strength and elongation (TS ⁇ EL).
  • the hole expanding ratio ⁇ was measured as an indicator for evaluating the stretch flangeability.
  • the hole expanding ratio ⁇ was determined by conducting a hole expanding test according to the Japan Iron and Steel Federation standard JFST1001 and determining the ratio from the initial diameter (10 mm ⁇ ) of the hole upon punching and the diameter of hole at the time the crack at the hole edge penetrated the sheet upon hole expanding.
  • the shock absorption property was determined by using a specimen 5 mm in width and 7 mm in length sampled from the steel sheet in a direction orthogonal to the rolling direction, conducting a tensile test at a strain rate of 2000/s, and integrating the stress-true strain curve obtained by the tensile test within the range of 0 to 10% to calculate the absorption energy (refer to Tetsu-to-Hagane, 83 (1997) p. 748 ).
  • the steel sheets of the examples of the present invention have excellent strength, ductility, and stretch flangeability, i.e., TS ⁇ EL of 22000 MPa ⁇ % or more and ⁇ of 70% or more.
  • the steel sheets of comparative examples outside the range of the present invention did not achieve excellent strength, ductility, and stretch flangeability unlike the steel sheets of the examples of the present invention since TS ⁇ EL was less than 22000 MPa ⁇ % and/or ⁇ was less than 70%.
  • the ratio of the absorption energy to TS is 0.063 or more, thereby achieving excellent crashworthiness.
  • the present invention can contribute to weight reduction and decreasing the fuel consumption of automobiles by providing a high-strength cold rolled steel sheet having excellent formability and crashworthiness.

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  • Chemical & Material Sciences (AREA)
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  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
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  • Heat Treatment Of Sheet Steel (AREA)

Claims (1)

  1. Procédé de fabrication d'une tôle d'acier laminée à froid, à haute résistance, dotée d'une ductilité et d'une étirabilité de bord remarquables, le procédé comprenant le laminage à chaud et le laminage à froid d'une brame ayant une composition comprenant, en termes de % en masse, C : 0,05 à 0,3 %, Si : 0,3 à 2,5 %, Mn : 0,5 à 3,5 %, P : 0,003 à 0,100 %, S : 0,02 % ou moins, Al : 0,010 à 0,5 %, facultativement au moins un élément choisi parmi Cr : 0,005 à 2,00 %, Mo : 0,005 à 2,00 %, V : 0,005 à 2,00 %, Ni : 0,005 à 2,00% et Cu : 0,005 à 2,00%, facultativement un ou les deux de Ti : 0,01 à 0,20 % et Nb : 0,01 à 0,20 %, facultativement B : 0,0002 à 0,005 %, facultativement un ou les deux de Ca : 0,001 à 0,005 % et terres rares : 0,001 à 0,005 %, et le reste étant du fer et des impuretés inévitables, pour fabriquer une tôle d'acier laminée à froid et le recuit continu de la tôle laminée à froid, dans lequel, durant le recuit continu, la tôle d'acier est chauffée à une vitesse moyenne de chauffage dans la plage de 500 °C au point de transformation Ac1 étant de 10 °C/s ou plus, maintenue à une température de 750 °C ou plus pendant 10 secondes ou plus, refroidie de 750 °C à une plage de température de 150 à 350 °C à une vitesse de refroidissement de 10 °C/s ou plus en moyenne, chauffée à une température de 350 à 600 °C, maintenue à cette température pendant 10 à 600 secondes, et refroidie à température ambiante, dans lequel la microstructure de la tôle d'acier laminée à froid, à haute résistance, inclut 20 % ou plus de ferrite en termes de fraction surfacique, 10 à 60 % de martensite trempée en termes de fraction surfacique, 0 à 10 % de martensite en termes de fraction surfacique, et 3 à 15 % d'austénite résiduelle en termes de fraction volumique.
EP10855912.1A 2010-08-12 2010-08-12 Procédé de fabrication d'une tôle d'acier laminée à froid à haute résistance ayant une excellente formabilité et résistance à l'impact Active EP2604715B1 (fr)

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Families Citing this family (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5440672B2 (ja) * 2011-09-16 2014-03-12 Ｊｆｅスチール株式会社 加工性に優れた高強度鋼板およびその製造方法
WO2013061545A1 (fr) * 2011-10-24 2013-05-02 Ｊｆｅスチール株式会社 Procédé de fabrication d'une feuille d'acier haute résistance ayant une aptitude supérieure au façonnage
IN2014DN07404A (fr) * 2012-02-22 2015-04-24 Nippon Steel & Sumitomo Metal Corp
JP6088322B2 (ja) 2012-03-30 2017-03-01 株式会社神戸製鋼所 耐焼付き性に優れた歯車
CN102899563B (zh) * 2012-11-01 2015-11-11 湖南华菱湘潭钢铁有限公司 一种超高强钢板的生产方法
CN102876972B (zh) * 2012-11-01 2015-10-28 湖南华菱湘潭钢铁有限公司 一种超高强钢板的生产方法
CN103805840B (zh) * 2012-11-15 2016-12-21 宝山钢铁股份有限公司 一种高成形性热镀锌超高强度钢板及其制造方法
CN103805838B (zh) 2012-11-15 2017-02-08 宝山钢铁股份有限公司 一种高成形性超高强度冷轧钢板及其制造方法
JP6264176B2 (ja) * 2013-04-23 2018-01-24 新日鐵住金株式会社 冷延鋼板およびその製造方法
JP5821911B2 (ja) * 2013-08-09 2015-11-24 Ｊｆｅスチール株式会社 高降伏比高強度冷延鋼板およびその製造方法
JP6322973B2 (ja) * 2013-11-28 2018-05-16 新日鐵住金株式会社 衝撃吸収特性に優れた高強度鋼
US10774405B2 (en) 2014-01-06 2020-09-15 Nippon Steel Corporation Steel and method of manufacturing the same
CN114438418A (zh) 2014-01-06 2022-05-06 日本制铁株式会社 热成形构件及其制造方法
CN105940134B (zh) 2014-01-29 2018-02-16 杰富意钢铁株式会社 高强度冷轧钢板及其制造方法
JP5896085B1 (ja) 2014-03-31 2016-03-30 Ｊｆｅスチール株式会社 材質均一性に優れた高強度冷延鋼板およびその製造方法
CN106170574B (zh) * 2014-03-31 2018-04-03 杰富意钢铁株式会社 高屈强比高强度冷轧钢板及其制造方法
KR101594670B1 (ko) 2014-05-13 2016-02-17 주식회사 포스코 연성이 우수한 고강도 냉연강판, 용융아연도금강판 및 이들의 제조방법
JP6379716B2 (ja) * 2014-06-23 2018-08-29 新日鐵住金株式会社 冷延鋼板及びその製造方法
JP6303866B2 (ja) * 2014-06-26 2018-04-04 新日鐵住金株式会社 高強度鋼材およびその製造方法
JP5983895B2 (ja) 2014-08-07 2016-09-06 Ｊｆｅスチール株式会社 高強度鋼板およびその製造方法、ならびに高強度亜鉛めっき鋼板の製造方法
WO2016021198A1 (fr) * 2014-08-07 2016-02-11 Ｊｆｅスチール株式会社 Tôle d'acier à haute résistance ainsi que procédé de fabrication de celle-ci, et procédé de fabrication de tôle d'acier galvanisé à haute résistance
WO2016021197A1 (fr) * 2014-08-07 2016-02-11 Ｊｆｅスチール株式会社 Tôle d'acier à haute résistance ainsi que procédé de fabrication de celle-ci, et procédé de fabrication de tôle d'acier galvanisé à haute résistance
US10590504B2 (en) * 2014-12-12 2020-03-17 Jfe Steel Corporation High-strength cold-rolled steel sheet and method for manufacturing the same
JP6435864B2 (ja) * 2015-01-07 2018-12-12 新日鐵住金株式会社 冷延鋼板およびその製造方法
KR101930186B1 (ko) * 2015-01-15 2018-12-17 제이에프이 스틸 가부시키가이샤 고강도 용융 아연 도금 강판 및 그 제조 방법
JP6417977B2 (ja) * 2015-01-29 2018-11-07 新日鐵住金株式会社 鋼板ブランク
KR102016432B1 (ko) * 2015-02-27 2019-08-30 제이에프이 스틸 가부시키가이샤 고강도 냉연 강판 및 그의 제조 방법
CN107406939B (zh) 2015-03-13 2018-12-18 杰富意钢铁株式会社 高强度冷轧钢板及其制造方法
JP6453140B2 (ja) * 2015-03-31 2019-01-16 株式会社神戸製鋼所 切断端面の耐遅れ破壊性に優れた高強度鋼板およびその製造方法
JP6554397B2 (ja) * 2015-03-31 2019-07-31 株式会社神戸製鋼所 加工性および衝突特性に優れた引張強度が９８０ＭＰａ以上の高強度冷延鋼板、およびその製造方法
DE102015106153A1 (de) * 2015-04-22 2016-10-27 Západoceská Univerzita V Plzni Verfahren zur Wärmebehandlung von Stahlteilen
CN105039846B (zh) * 2015-08-17 2016-09-14 攀钢集团攀枝花钢铁研究院有限公司 钒微合金化tam钢及其制造方法
WO2017109538A1 (fr) * 2015-12-21 2017-06-29 Arcelormittal Procédé de production d'une tôle d'acier présentant une résistance, une ductilité et une aptitude au formage améliorées
WO2017109542A1 (fr) * 2015-12-21 2017-06-29 Arcelormittal Procédé de fabrication d'une tôle d'acier à haute résistance présentant une ductilité et une formabilité améliorées et tôle d'acier obtenue par ce procédé
WO2017109540A1 (fr) * 2015-12-21 2017-06-29 Arcelormittal Procédé de fabrication d'une tôle d'acier à haute résistance ayant une ductilité et une aptitude au formage améliorées et tôle d'acier ainsi obtenue
WO2017109541A1 (fr) 2015-12-21 2017-06-29 Arcelormittal Procédé de production d'une tôle d'acier revêtue de haute résistance présentant une ductilité et une aptitude au formage améliorées, et tôle d'acier revêtue ainsi obtenue
US11091818B2 (en) 2015-12-23 2021-08-17 Posco High strength cold-rolled steel sheet and hot-dip galvanized steel sheet having excellent hole expansion, ductility and surface treatment properties, and method for manufacturing same
KR102121415B1 (ko) 2016-04-14 2020-06-10 제이에프이 스틸 가부시키가이샤 고강도 강판 및 그의 제조 방법
WO2017222160A1 (fr) * 2016-06-21 2017-12-28 현대제철 주식회사 Tôle d'acier haute résistance laminée à froid ayant une excellente aptitude au pliage, et son procédé de fabrication
BR112018073110A2 (pt) 2016-08-08 2019-03-06 Nippon Steel & Sumitomo Metal Corp chapa de aço
US11136644B2 (en) 2016-08-31 2021-10-05 Jfe Steel Corporation High-strength cold rolled steel sheet and method for producing the same
EP3719155B1 (fr) * 2017-11-29 2024-04-03 JFE Steel Corporation Tôle en acier laminée à froid hautement résistante, et procédé de fabrication de celle-ci
JP6597938B1 (ja) * 2018-01-31 2019-10-30 Ｊｆｅスチール株式会社 高強度冷延鋼板、高強度めっき鋼板及びそれらの製造方法
MX2020010313A (es) 2018-03-30 2020-10-22 Jfe Steel Corp Lamina de acero de alta resistencia y metodo para su produccion.
CN112703265A (zh) * 2018-10-04 2021-04-23 日本制铁株式会社 冷轧钢板
KR102508292B1 (ko) * 2019-01-29 2023-03-09 제이에프이 스틸 가부시키가이샤 고강도 강판 및 그 제조 방법
CN112760554A (zh) * 2019-10-21 2021-05-07 宝山钢铁股份有限公司 一种延展性优异的高强度钢及其制造方法
CN117660846A (zh) * 2022-08-23 2024-03-08 宝山钢铁股份有限公司 一种120公斤级冷轧低合金退火双相钢及其制造方法

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0670247B2 (ja) 1988-10-05 1994-09-07 新日本製鐵株式会社 成形性良好な高強度鋼板の製造方法
JP3587126B2 (ja) * 1999-04-21 2004-11-10 Ｊｆｅスチール株式会社 延性に優れる高張力溶融亜鉛めっき鋼板およびその製造方法
JP4188608B2 (ja) * 2001-02-28 2008-11-26 株式会社神戸製鋼所 加工性に優れた高強度鋼板およびその製造方法
KR100627429B1 (ko) * 2001-10-04 2006-09-25 신닛뽄세이테쯔 카부시키카이샤 드로잉이 가능하고 형상 동결성이 우수한 고강도 박강판과 이를 제조하는 방법
JP4119758B2 (ja) * 2003-01-16 2008-07-16 株式会社神戸製鋼所 加工性および形状凍結性に優れた高強度鋼板、並びにその製法
JP2004256872A (ja) * 2003-02-26 2004-09-16 Jfe Steel Kk 伸びおよび伸びフランジ性に優れる高張力冷延鋼板およびその製造方法
EP1512760B1 (fr) * 2003-08-29 2011-09-28 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Haute tôle d'acier de la fermeté d'extension excellent l'usinabilité et processus pour son fabrication
KR100948998B1 (ko) * 2005-03-31 2010-03-23 가부시키가이샤 고베 세이코쇼 도막 밀착성, 가공성 및 내수소취화 특성이 우수한 고강도 냉연 강판 및 자동차용 강 부품
KR20100046057A (ko) * 2007-10-25 2010-05-04 제이에프이 스틸 가부시키가이샤 가공성이 우수한 고강도 용융 아연 도금 강판 및 그 제조 방법
JP5369663B2 (ja) * 2008-01-31 2013-12-18 Ｊｆｅスチール株式会社 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
JP4894863B2 (ja) * 2008-02-08 2012-03-14 Ｊｆｅスチール株式会社 加工性に優れた高強度溶融亜鉛めっき鋼板およびその製造方法
JP5463685B2 (ja) * 2009-02-25 2014-04-09 Ｊｆｅスチール株式会社 加工性および耐衝撃性に優れた高強度冷延鋼板およびその製造方法
KR20140099544A (ko) * 2011-12-26 2014-08-12 제이에프이 스틸 가부시키가이샤 고강도 박강판 및 그의 제조 방법
WO2014020640A1 (fr) * 2012-07-31 2014-02-06 Ｊｆｅスチール株式会社 Tôle d'acier galvanisée par immersion à chaud à résistance élevée qui présente une excellente aptitude au moulage et une excellente aptitude à la fixation de formes, ainsi que procédé de fabrication de cette dernière

Non-Patent Citations (1)

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

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WO2012020511A1 (fr) 2012-02-16
EP2604715A1 (fr) 2013-06-19
US20130133792A1 (en) 2013-05-30
EP2604715A4 (fr) 2017-12-13
MX2013001456A (es) 2013-04-29
CA2805834C (fr) 2016-06-07
KR20130036763A (ko) 2013-04-12
CN103069040A (zh) 2013-04-24
CA2805834A1 (fr) 2012-02-16

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