EP2527482B1 - Procédé de production d'une tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement - Google Patents

Procédé de production d'une tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement Download PDF

Info

Publication number
EP2527482B1
EP2527482B1 EP11734786.4A EP11734786A EP2527482B1 EP 2527482 B1 EP2527482 B1 EP 2527482B1 EP 11734786 A EP11734786 A EP 11734786A EP 2527482 B1 EP2527482 B1 EP 2527482B1
Authority
EP
European Patent Office
Prior art keywords
less
invention example
comparative example
steel sheet
temperature range
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.)
Active
Application number
EP11734786.4A
Other languages
German (de)
English (en)
Other versions
EP2527482A4 (fr
EP2527482A1 (fr
Inventor
Yoshiyasu Kawasaki
Tatsuya Nakagaito
Shinjiro Kaneko
Yasunobu Nagataki
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.)
JFE Steel Corp
Original Assignee
JFE Steel Corp
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 JFE Steel Corp filed Critical JFE Steel Corp
Publication of EP2527482A1 publication Critical patent/EP2527482A1/fr
Publication of EP2527482A4 publication Critical patent/EP2527482A4/fr
Application granted granted Critical
Publication of EP2527482B1 publication Critical patent/EP2527482B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • C21D8/0205—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
    • 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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0405—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing 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
    • 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
    • C22C38/12—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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0224—Two or more thermal pretreatments
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
    • C23C2/06—Zinc or cadmium or alloys based thereon
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C23C2/28—Thermal after-treatment, e.g. treatment in oil bath
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/002—Bainite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—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
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/009—Pearlite

Definitions

  • the present invention relates to a high strength galvanized steel sheet, which is suitable for a member used in industrial fields of automobile, electricity, and the like and which has excellent formability and stability of mechanical properties, and a method for manufacturing the same.
  • the shape fixability is degraded by an increase in strength and thickness reduction of a steel sheet significantly.
  • press forming it has been widely performed that changes in shape after release from a mold is predicted and the mold is designed in expectation of the amount of change in shape.
  • TS tensile strength
  • deviation from the expected amount, in which these are assumed to be constant becomes large and odd shapes occur. Consequently, rework, e.g., sheet-metal working of the shape on a one-by-one basis, becomes necessary after press-forming, and the efficiency in mass production is degraded significantly. Therefore, it is required that variations in TS of the steel sheet are minimized.
  • Japanese Unexamined Patent Application Publication No. 2001-140022 has proposed a steel sheet having excellent elongation by specifying the chemical components and specifying the volume ratios of retained austenite and martensite and methods for manufacturing the same.
  • Japanese Unexamined Patent Application Publication No. 04-026744 has proposed a steel sheet having excellent elongation by specifying the chemical components and, furthermore, specifying a special method for manufacturing the same.
  • Japanese Unexamined Patent Application Publication No. 2007-182625 has proposed a steel sheet having excellent elongation by specifying the chemical components and specifying the volume ratios of ferrite, bainitic ferrite, and retained austenite phases.
  • CA 2714117 A1 discloses a method for manufacturing a high strength galvanized steel sheet with excellent formability and a martensite content of 5-40%.
  • the present inventors performed intensive research to obtain a high strength galvanized steel sheet having high tensile strength TS of 540 MPa or more and, in addition, having excellent stability of mechanical properties and formability (high elongation and high stretch flangeability) and found the following.
  • high strength galvanized steel sheet refers to a galvanized steel sheet having a tensile strength TS of 540 MPa or more.
  • galvanized steel sheets steel sheets in which a zinc coating is applied to a steel sheet by galvanization are generically called galvanized steel sheets.
  • the galvanized steel sheets in the present invention are subjected to an alloying treatment.
  • a high strength galvanized steel sheet which has a tensile strength TS of 540 MPa or more, which has excellent formability because of high elongation and high stretch flangeability and, furthermore, which has excellent stability of mechanical properties, is obtained.
  • TS tensile strength
  • TS tensile strength
  • the high strength galvanized steel sheet according to the present invention is applied to, for example, an automobile structural member, enhancement of fuel economy due to weight reduction of a car body can be facilitated. Therefore, an industrial utility value is very large.
  • Si was added intentionally for the purpose of solution hardening of ferrite and an improvement of a work hardening property of ferrite, a microstructure including ferrite, bainitic ferrite, pearlite, a small amount of martensite was formed, a hardness difference between different phases was reduced, and furthermore, the area ratios of the multi phases were optimized, so that it was made possible to ensure the compatibility between high elongation and high stretch flangeability and ensure the stability of mechanical properties.
  • a component composition contains C: 0.04% or more, and 0.13% or less, Si: 0.7% or more, and 2.3% or less, Mn: 0.8% or more, and 2.0% or less, P: 0.1% or less, S: 0.01% or less, A1: 0.1% or less, N: 0.008% or less, and the remainder composed of Fe and incidental impurities on a percent by mass basis, wherein a steel microstructure includes 75% or more of ferrite phase, 1.0% or more of bainitic ferrite phase, and 1.0% or more, and 10.0% or less of pearlite phase on an area ratio basis, the area ratio of martensitic phase is 1.0% or more, and less than 5.0%, and the area ratio of martensitic phase/(area ratio of bainitic ferrite phase + area ratio of pearlite phase) ⁇ 0.6 is satisfied.
  • Carbon is an austenite forming element and is an element indispensable for strengthening a steel. If the amount of C is less than 0.04%, it is difficult to ensure desired strength. On the other hand, if the amount of C exceeds 0.13% and, therefore, addition is excessive, a welded zone and a heat-affected zone are hardened significantly, and the mechanical characteristics of the welded zone are degraded, so that the spot weldability, the arc weldability, and the like are degraded. Therefore, C is specified to be 0.04% or more, and 0.13% or less.
  • Si 0.7% or more, and 2.3% or less
  • Silicon is a ferrite forming element and is also an element effective in solution hardening.
  • 0.7% or more of addition is necessary to ensure good elongation due to an improvement in work hardening property of the ferrite phase.
  • 0.7% or more of addition is also necessary to ensure a desired area ratio of bainitic ferrite phase and ensure good stretch flangeability.
  • excessive addition of Si causes degradation of surface quality due to an occurrence of red scale and the like and degradation of deposition and adhesion of the coating. Therefore, Si is specified to be 0.7% or more, and 2.3% or less, and preferably 1.2% or more, and 1.8% or less.
  • Mn 0.8% or more, and 2.0% or less
  • Manganese is an element effective in strengthening a steel. Furthermore, Mn is an element to stabilize austenite and an element necessary for adjusting the ratio of a secondary phase. For this purpose, addition of 0.8% or more of Mn is necessary. On the other hand, if addition is excessive and exceeds 2.0%, the area ratio of martensitic phase in the secondary phase increases and it becomes difficult to ensure the stability of mechanical properties. Moreover, an increase in cost is brought about because an alloy cost of Mn has increased in recent years. Therefore, Mn is specified to be 0.8% or more, and 2.0% or less, and preferably 1.0% or more, and 1.8% or less.
  • Phosphorus is an element effective in strengthening a steel. However, if addition is excessive and exceeds 0.1%, embrittlement is caused by grain boundary segregation, and the crashworthiness is degraded. Furthermore, if 0.1% is exceeded, an alloying speed is reduced significantly. Therefore, P is specified to be 0.1% or less.
  • Sulfur forms inclusions, e.g., MnS, to cause degradation in crashworthiness and cracking along a metal flow of a welded zone and, therefore, is minimized, although S is specified to be 0.01% or less from the viewpoint of production cost.
  • the amount of addition is specified to be 0.01% or more because if the amount is less than 0.01%, a large number of coarse oxides of Mn, Si, and the like are dispersed in the steel to degrade the mechanical properties. Therefore, the amount of Al is specified to be 0.1% or less, and preferably 0.01% to 0.1%.
  • Nitrogen is an element which degrades the aging resistance of a steel to a greatest extent and preferably is minimized. If 0.008% is exceeded, degradation of the aging resistance becomes significant. Therefore, N is specified to be 0.008% or less.
  • the remainder is composed of Fe and incidental impurities. However, besides these elements, at least one type selected from the following elements can be added, as necessary.
  • Chromium, vanadium, and molybdenum have a function of improving the balance between the strength and the elongation and, therefore, can be added as necessary.
  • the effect thereof is obtained when Cr: 0.05% or more, V: 0.005% or more, and Mo: 0.005% or more are employed.
  • Cr, V, and Mo are added in such a way as to exceed Cr: 1.0%, V: 0.5%, and Mo: 0.5%, respectively, the secondary phase ratio becomes too large, and a significant increase in strength and the like may occur. Furthermore, an increase in cost is brought about. Therefore, in the case where these elements are added, the individual amounts thereof are specified to be Cr: 1.0% or less, V: 0.5% or less, and Mo: 0.5% or less.
  • Nickel and copper are elements effective in strengthening a steel and there is no problem in use for strengthening the steel within the bounds of the specification of the present invention. Furthermore, there is a function of facilitating internal oxidation so as to improve adhesion of the coating. In order to obtain these effects, it is necessary that each of Ni and Cu is 0.05% or more. On the other hand, if both Ni and Cu, each exceeding 1.0%, are added, the formability of the steel sheet is degraded. Moreover, an increase in cost is brought about. Therefore, in the case where Ni and Cu are added, the amount of addition of each of them is specified to be 0.05% or more, and 1.0% or less.
  • Titanium and niobium are effective in precipitation hardening of a steel.
  • the effect is obtained when each of them is 0.01% or more and, therefore, there is no problem in use for strengthening the steel within the bounds of the specification of the present invention.
  • each of them exceeds 0.1%, the formability and the shape fixability are degraded.
  • an increase in cost is brought about. Therefore, in the case where Ti and Nb are added, the amount of addition of Ti is specified to be 0.01% or more, and 0.1% or less and Nb is specified to be 0.01% or more, and 0.1% or less.
  • B has a function of suppressing generation and growth of ferrite from austenite grain boundaries and, therefore, can be added as necessary.
  • the effect is obtained when B is 0.0003% or more. However, if 0.0050% is exceeded, the formability is degraded. Furthermore, an increase in cost is brought about. Therefore, in the case where B is added, B is specified to be 0.0003% or more, and 0.0050% or less.
  • Calcium and REM are elements effective in spheroidizing the shape of a sulfide to improve an adverse influence of the sulfide on the stretch flangeability.
  • each of Ca and REM is 0.001% or more.
  • excessive addition causes increases in inclusions and the like so as to cause surface and internal defects. Therefore, in the case where Ca and REM are added, the amounts of addition of each of them is specified to be 0.001% or more, and 0.005% or less.
  • tantalum has effects of not only contributing to an increase in strength by forming alloy carbides and alloy carbonitrides, but also stabilizing contribution of precipitation hardening to the strength by partially making solid solution with Nb carbide and Nb carbonitride to form complex precipitates, e.g., (Nb,Ta)(C,N), and thereby, suppress coarsening of precipitates significantly in the same manner as Ti and Nb. Consequently, in the case where Ta is added, it is desirable that the content thereof is specified to be 0.001% or more. However, if addition is excessive, not only the above-described precipitation stabilizing effect is saturated, but also an alloy cost increases. Therefore, in the case where Ta is added, it is desirable that the content thereof is specified to be 0.010% or less.
  • Tin can be added from the viewpoint of suppressing nitriding and oxidation of a steel sheet surface or decarbonization of several ten micrometers of region of a steel sheet surface layer generated through oxidation. Suppression of such nitriding and oxidation prevents reduction in the amount of generation of martensite on the steel sheet surface and improves the fatigue resistance and the aging resistance. From the viewpoint of suppression of nitriding and oxidation, in the case where Sn is added, it is desirable that the content thereof is specified to be 0.002% or more, and it is desirable that the content thereof is specified to be 0.2% or less because if 0.2% is exceeded, reduction in toughness is brought about.
  • Sb can be added from the viewpoint of suppressing nitriding and oxidation of a steel sheet surface or decarbonization of several ten micrometers of region of a steel sheet surface layer generated through oxidation. Suppression of such nitriding and oxidation prevents reduction in the amount of generation of martensite on the steel sheet surface and improves the fatigue resistance and the aging resistance. From the viewpoint of suppression of nitriding and oxidation, in the case where Sb is added, it is desirable that the content thereof is specified to be 0.002% or more, and it is desirable that the content thereof is specified to be 0.2% or less because if 0.2% is exceeded, reduction in toughness is brought about.
  • a ferrite phase is 75% or more on an area ratio basis.
  • the area ratio of bainitic ferrite phase is 1.0% or more.
  • Area ratio of pearlite phase 1.0% or more, and less than 10.0%
  • the area ratio of pearlite phase is specified to be 1.0% or more. In order to ensure desired balance between the strength and the elongation, the area ratio of pearlite phase is specified to be 10.0% or less.
  • the area ratio of martensitic phase is specified to be 1.0% or more. In order to ensure good stability of mechanical properties, it is necessary that the area ratio of martensitic phase having a large influence on the tensile characteristics (TS, EL) is specified to be 5.0% or less.
  • the amount of martensite which causes variations in mechanical properties, is reduced and the amount of bainitic ferrite and pearlite softer than martensite are increased, that is, the area ration of martensitic phase/(area ration of bainitic ferrite phase + area ratio of pearlite phase) ⁇ 0.6 is satisfied.
  • retained austenite, tempered martensite, and carbides e.g., cementite
  • carbides e.g., cementite
  • the purpose of the present invention can be achieved insofar as the above-described area rations of ferrite, bainitic ferrite, pearlite, and martensitic phases are satisfied.
  • the area ratios of ferrite, bainitic ferrite, pearlite, and martensitic phases refer to proportions of the areas of the individual phases constituting an observation area.
  • the high strength galvanized steel sheet produced according to the present invention includes the steel sheet having the above-described component composition and the above-described steel microstructure and serving as a substrate steel sheet and a coating film subjected to an alloying treatment after galvanization on the substrate steel sheet.
  • the high strength galvanized steel sheet according to the present disclosure is produced by subjecting a steel slab having the component composition conforming to the above-described component composition range to hot rolling and pickling, or hot rolling, pickling, and cold rolling, performing heating to a temperature range of 650°C or higher at an average heating range of 5°C/s or more, followed by keeping in a temperature range of 750°C to 900°C for 15 to 600s, performing cooling to a temperature range of 450°C to 550°C, followed by keeping in the temperature range of 450°C To 550°C for 10 to 200s, and performing galvanization.
  • the alloying treatment of zinc coating is performed in a temperature range of 500°C to 600°C under the condition satisfying the following formula, 0.45 ⁇ exp 200 / 400 ⁇ T ⁇ 1 ⁇ n t ⁇ 1.0
  • a steel having the above-described component Composition is melted, is made into a slab through roughing or continuous casting, and is made into a hat rolled sheet through hot rolling by a known method.
  • hot rolling it is preferable that the slab is heated to 1,100°C to 1,300°C, hot rolling is performed at a final finishing temperature of 850°C or higher, and steel sheet is coiled at 400°C to 650°C.
  • carbides in the hot-rolled sheet may become coarse, and required strength cannot be obtained in some cases because such coarse carbides are not melted completely during soaking in annealing.
  • a pickling treatment is performed by a known method.
  • cold rolling is further performed.
  • the condition thereof is not necessarily specifically limited, although it is preferable that the cold rolling is performed under the cold reduction ratio of 30% or more. This is because if the cold reduction ratio is low, in some cases, recrystallization of ferrite is not facilitated, unrecrystallized ferrite remains, and the elongation and the stretch flangeability are degraded.
  • the pickled hot rolled sheet or the cold rolled steel sheet is subjected to annealing described below and, then, cooling and galvanization are performed.
  • the average heating rate in heating to the temperature range of 650°C or higher is less than 5°C/s, a fine uniformly dispersed austenite phase is not generated during annealing, the area ratio of martensitic phase in the final microstructure increases and it is difficult to ensure good stretch flangeability. Furthermore, a furnace longer than a usual furnace is necessary and, thereby, an increase in cost associated with large energy consumption and reduction in production efficiency are brought about. It is preferable that a direct fired furnace (DFF) is used as a furnace. This is because an internal oxide layer is formed through rapid heating by the DFF and, thereby, concentration of oxides of Si, Mn, and the like on the outermost layer of the steel sheet is prevented so as to ensure good wettability of the coating.
  • DFF direct fired furnace
  • Annealing which is keeping in a temperature range of 750°C to 900°C, specifically in a single phase region of austenite or in a two-phase region of austenite and ferrite, for 15 to 600 s is performed.
  • the annealing temperature is lower than 750°C or the annealing time is less than 15 s, hard cementite in the steel sheet is not dissolved sufficiently, so that the stretch flangeability is degraded, and furthermore, a desired area ratio of martensitic phase is not obtained, so that the elongation is degraded.
  • the annealing temperature exceeds 900°C
  • austenite particles grow significantly, it becomes difficult to ensure bainitic ferrite due to bainite transformation which occurs in the keeping after cooling, so that the stretch flangeability is degraded.
  • the area ratio of martensitic phase/(area ratio of bainitic ferrite phase + area ratio of pearlite phase) exceeds 0.6, so that good stability of mechanical properties are not obtained.
  • the keeping time exceeds 600 s, austenite becomes coarse, it becomes difficult to ensure desired strength, and an increase in cost associated with large energy consumption may be brought about.
  • the keeping temperature becomes lower than 450°C or the keeping time exceeds 200 s, most of the secondary phase is converted to austenite and bainitic ferrite, which are generated through facilitation of bainite transformation and which contain large amounts of carbon in solid solution, so that a desired area ratio of perlite phase of 1.0% or more is not obtained. Furthermore, the area ratio of hard martensitic phase becomes 5.0% or more, so that good stretch flangeability and stability of mechanical properties are not obtained.
  • the steel sheet is dipped into a coating bath at a usual bath temperature so as to be galvanized, and the amount of deposition of coating is adjusted through gas wiping or the like, followed by cooling, so that a high strength galvanized steel sheet having a coating layer not subjected to alloying is obtained.
  • the alloying treatment of zinc coating is further performed in a temperature range of 500°C to 600°C under the condition satisfying the following formula, 0.45 ⁇ exp [ 200 / 400 ⁇ T ⁇ ln t ⁇ 1.0 where
  • Alloying of the coating layer can be performed in the scope of the present invention, in which the temperature is in the range of 500°C to 600°C and the above-described condition of exp[200/(400 - T)] ⁇ ln(t) is satisfied, without problems.
  • the keeping temperature is not necessary constant insofar as the temperature is in the above-described range. Furthermore, even in the case where the cooling rate is changed during cooling, the present invention is not impaired insofar as the rate is in the specified range.
  • the steel sheet may be subjected to a heat treatment by any equipment insofar as only the heat history is satisfied.
  • a steel is produced through usual steps of steel making, casting, and hot rolling. However, for example, the steel may be produced through thin wall casting or the like, where a part of or whole hot rolling step is omitted.
  • Fig. 1 and Fig. 2 are diagrams showing the organized relationships between TS and the annealing temperature (T 1 ) and between EL and the annealing temperature (T 1 ) with respect to Nos. 15, 16, and 17 of Steel A, which are invention examples, (Table 2 and Table 5) and Nos. 18, 19, and 20 of Steel H, which are comparative examples, (Table 2 and Table 5) in Examples described later.
  • Table 2 and Table 5 are diagrams showing the organized relationships between TS and the annealing temperature (T 1 ) and between EL and the annealing temperature (T 1 ) with respect to Nos. 15, 16, and 17 of Steel A, which are invention examples, (Table 2 and Table 5) and Nos. 18, 19, and 20 of Steel H, which are comparative examples, (Table 2 and Table 5) in Examples described later.
  • Table 2 and Table 5 are diagrams showing the organized relationships between TS and the annealing temperature (T 1 ) and between EL and the annealing temperature (T 1 ) with respect to Nos
  • Fig. 3 and Fig. 4 are diagrams showing the organized relationships between TS and the average keeping time (T 2 ) in cooling after annealing and between EL and the average keeping time (T 2 ) with respect to Nos. 21, 22, and 23 of Steel A, which are invention examples, (Table 2 and Table 5) and Nos. 24, 25, and 26 of Steel H, which are comparative examples, (Table 2 and Table 5) in Examples described later.
  • Table 2 and Table 5 are invention examples, (Table 2 and Table 5) and Nos. 24, 25, and 26 of Steel H, which are comparative examples, (Table 2 and Table 5) in Examples described later.
  • FIG. 3 and Fig. 4 regarding Steel A of the invention example, variations in TS and EL associated with changes in average keeping time are small, whereas variations in TS and EL are large regarding Steel H of the comparative example.
  • the resulting slab was heated to 1,200°C, hot rolling to a sheet thickness of 3.2 mm was performed at a finish temperature of 870°C to 920°C, and coiling was performed at 520°C. Subsequently, the resulting hot-rolled sheet was pickled. A part of the resulting hot-rolled sheets were served as pickled hot-rolled steel sheets, and a part of the hot-rolled sheets were subjected to cold rolling, so as to produce cold-rolled steel sheets.
  • the hot-rolled steel sheet (after pickling) and the cold-rolled steel sheet obtained as described above were subjected to an annealing treatment and a galvanizing treatment with a continuous galvanization line under the production condition shown in Tables 2 to 4. Furthermore, an alloying treatment of the plating layer was performed, so as to obtain a galvannealed steel sheet.
  • the amount of deposition of coating was specified to be 30 to 50 g/m 2 on one surface basis.
  • galvanized steel sheets which were not subjected to an alloying treatment after being galvanized, were also produced. Table 2 No.
  • the area ratios of ferrite, bainitic ferrite, pearlite, and martensitic phases were determined by polishing a sheet thickness cross-section parallel to a rolling direction of the steel sheet, followed by corroding with 3% nital, and observing 10 visual fields with a scanning electron microscope (SEM) under a magnification of 2,000 times through the use of Image-Pro of Media Cybernetics, Inc. At that time, it was difficult to distinguish martensite and retained austenite.
  • SEM scanning electron microscope
  • the resulting galvanized steel sheet was subjected to a tempering treatment at 200°C for 2 hours, the microstructure of a sheet thickness cross-section parallel to the rolling direction of the steel sheet was observed by the above-described method, and the aria ratio of tempered martensitic phase determined by the above-described method was taken as the aria ratio of martensitic phase. Furthermore, the volume ratio of retained austenite phase was determined on the basis of integrated intensity of ferrite and austenite peaks of a face at one-quarter sheet thickness, where the steel sheet was polished up to the one-quarter face in the sheet thickness direction.
  • X-ray diffractometer using Co-K ⁇ was used, the intensity ratios were determined with respect to all combinations of integrated intensities of peaks of ⁇ 111 ⁇ , ⁇ 200 ⁇ , ⁇ 220 ⁇ , and ⁇ 311 ⁇ faces of retained austenite phase and ⁇ 110 ⁇ , ⁇ 200 ⁇ , and ⁇ 211 ⁇ faces of ferrite phase, and the average value of them was taken as the volume ratio of retained austenite phase.
  • a tensile test was performed on the basis of JIS Z2241 by using JIS No. 5 test piece, where sample was taken in such a way that a tensile direction becomes in the direction orthogonal to the rolling direction of the steel sheet, and the tensile strength (TS) and the total elongation (EL) were measured.
  • TS tensile strength
  • EL total elongation
  • the hole expansion property (stretch flangeability) was measured.
  • the hole expansion property (stretch flangeability) was measured on the basis of the Japan Iron and Steel Federation Standard JFST1001.
  • critical hole expansion ratio ⁇ (%) ⁇ (D f - D 0 ) / D 0 ⁇ ⁇ 100 where D f represents a hole diameter (mm) when cracking occurred and D 0 represents an initial hole diameter (mm).
  • D f represents a hole diameter (mm) when cracking occurred
  • D 0 represents an initial hole diameter (mm).
  • Every high strength galvanized steel sheet produced with a method according to the present invention has TS of 540 MPa or more and has ⁇ of 70% or more so as to exhibit excellent stretch flangeability. Furthermore, TS ⁇ EL ⁇ 19,000 MPa ⁇ % is satisfied and the balance between the strength and the elongation is high. Therefore, it is clear that a high strength galvanized steel sheet having excellent formability is obtained. Moreover, the values of ⁇ TS and ⁇ EL are small and, therefore, it is clear that a high strength galvanized steel sheet having excellent stability of mechanical properties is obtained. On the other hand, regarding comparative examples, at least one of the elongation and the stretch flangeability is poor, or the stability of mechanical properties is not favorable.
  • the high strength galvanized steel sheet produced according to the present invention has a tensile strength TS of 540 MPa or more, exhibits high elongation and high stretch flangeability, and has excellent stability of mechanical properties.
  • TS tensile strength
  • the high strength galvanized steel sheet according to the present invention is applied to, for example, an automobile structural member, enhancement of fuel economy due to weight reduction of a car body can be facilitated. Therefore, an industrial utility value is very large.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Coating With Molten Metal (AREA)

Claims (1)

  1. Procédé de fabrication d'une tôle en acier galvanisé à haute résistance présentant d'excellentes propriétés mécaniques de formage et de stabilité, comprenant les étapes de soumission d'une plaque d'acier dont la composition consiste en C : supérieur ou égal à 0,04 % et inférieur ou égal à 0,13 %, Si : supérieur ou égal à 0,7 % et inférieur ou égal à 2,3 %, Mn : supérieur ou égal à 0,8 % et inférieur ou égal à 2,0 %, P : inférieur ou égal à 0,1 %, S : inférieur ou égal à 0,01 %, Al : inférieur ou égal à 0,1 %, N : inférieur ou égal à 0,008 %, et éventuellement au moins un élément sélectionné parmi Cr : supérieur ou égal à 0,05 % et inférieur ou égal à 1,0 %, V : supérieur ou égal à 0,005 % et inférieur ou égal à 0,5 %, Mo : supérieur ou égal à 0,005 % et inférieur ou égal à 0,5 %, Ni : supérieur ou égal à 0,05 % et inférieur ou égal à 1,0 %, Cu : supérieur ou égal à 0,05 % et inférieur ou égal à 1,0 %, Ti : supérieur ou égal à 0,01 % et inférieur ou égal à 0,1 %, Nb : supérieur ou égal à 0,01 % et inférieur ou égal à 0,1 %, et B : supérieur ou égal à 0,0003 % et inférieur ou égal à 0,0050 %, Ca : supérieur ou égal à 0,001 % et inférieur ou égal à 0,005 %, terres rares : supérieur ou égal à 0,001 % et inférieur ou égal à 0,005 %, Ta : supérieur ou égal à 0,001 % et inférieur ou égal à 0,010 %, Sn : supérieur ou égal à 0,002 % et inférieur ou égal à 0,2 %, et Sb : supérieur ou égal à 0,002 % et inférieur ou égal à 0,2 %, le reste étant composé de Fe et d'impuretés inévitables, en pourcentage massique, à un laminage à chaud et décapage, ou à un laminage à chaud, décapage et laminage à froid, en mettant en œuvre une chauffe jusqu'à une plage de température supérieure ou égale à 650 °C à une vitesse de chauffe moyenne supérieure ou égale à 5 °C/s, suivie par un maintien dans une plage de température de 750 °C à 900 °C durant 15 à 600 s, en mettant en œuvre un refroidissement dans une plage de température de 450 °C à 550 °C, suivi par un maintien dans la plage de température de 450 °C à 550 °C durant 10 à 200 s, et en mettant en œuvre une galvanisation, dans lequel, après la mise en œuvre de la galvanisation, un traitement d'alliage du revêtement de zinc est mis en œuvre dans une plage de température de 500 °C à 600 °C sous la condition répondant à la formule suivante : 0,45 ≤ exp 200 / 400 − T × ln t ≤ 1,0
    Figure imgb0004
     où
    T est la température moyenne de maintien (°C) dans une plage de température de 500 °C à 600 °C,
    t est le temps de maintien (s) dans une plage de température de 500 °C à 600 °C, et
    exp(X) et ln(X) représentent respectivement la fonction exponentielle et le logarithme naturel de X.
EP11734786.4A 2010-01-22 2011-01-18 Procédé de production d'une tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement Active EP2527482B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2010011948 2010-01-22
JP2010262087A JP5786317B2 (ja) 2010-01-22 2010-11-25 材質安定性と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
PCT/JP2011/051151 WO2011090180A1 (fr) 2010-01-22 2011-01-18 Tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement et procédé de production de celle-ci

Publications (3)

Publication Number Publication Date
EP2527482A1 EP2527482A1 (fr) 2012-11-28
EP2527482A4 EP2527482A4 (fr) 2017-04-05
EP2527482B1 true EP2527482B1 (fr) 2019-12-25

Family

ID=44306981

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11734786.4A Active EP2527482B1 (fr) 2010-01-22 2011-01-18 Procédé de production d'une tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement

Country Status (4)

Country Link
EP (1) EP2527482B1 (fr)
JP (1) JP5786317B2 (fr)
TW (1) TWI433961B (fr)
WO (1) WO2011090180A1 (fr)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4998756B2 (ja) * 2009-02-25 2012-08-15 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
JP4883216B2 (ja) * 2010-01-22 2012-02-22 Ｊｆｅスチール株式会社 加工性とスポット溶接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
JP5862002B2 (ja) * 2010-09-30 2016-02-16 Ｊｆｅスチール株式会社 疲労特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
JP5246283B2 (ja) * 2011-02-28 2013-07-24 Ｊｆｅスチール株式会社 伸びと伸びフランジ性に優れた低降伏比高強度冷延鋼板およびその製造方法
JP5793971B2 (ja) 2011-06-01 2015-10-14 Ｊｆｅスチール株式会社 材質安定性、加工性およびめっき外観に優れた高強度溶融亜鉛めっき鋼板の製造方法
WO2013047760A1 (fr) * 2011-09-30 2013-04-04 新日鐵住金株式会社 Feuille d'acier galvanisé par immersion à chaud et à haute résistance qui présente une excellente résistance à la rupture différée et procédé de production correspondant
JP5267638B2 (ja) * 2011-11-17 2013-08-21 Ｊｆｅスチール株式会社 高強度溶融亜鉛めっき鋼板または高強度合金化溶融亜鉛めっき鋼板用熱延鋼板およびその製造方法
WO2013179497A1 (fr) * 2012-06-01 2013-12-05 Ｊｆｅスチール株式会社 Tôle en acier laminée à froid haute résistance à faible rapport de limite d'élasticité présentant un excellent allongement et une excellente formabilité de bord tombé, et son procédé de fabrication
TWI454582B (zh) * 2012-06-13 2014-10-01 Jfe Steel Corp 延伸及延伸凸緣性優異之低降伏比高強度冷延鋼板及其製造方法
RU2599934C2 (ru) * 2012-08-15 2016-10-20 Ниппон Стил Энд Сумитомо Метал Корпорейшн Стальной лист для горячей штамповки, способ его изготовления и изделие из горячештампованного стального листа

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4110680B2 (ja) * 1999-08-02 2008-07-02 Ｊｆｅスチール株式会社 極低炭素薄鋼板の製造方法
JP3912181B2 (ja) * 2002-03-28 2007-05-09 Ｊｆｅスチール株式会社 深絞り性と伸びフランジ性に優れた複合組織型高張力溶融亜鉛めっき冷延鋼板およびその製造方法
JP5151246B2 (ja) * 2007-05-24 2013-02-27 Ｊｆｅスチール株式会社 深絞り性と強度−延性バランスに優れた高強度冷延鋼板および高強度溶融亜鉛めっき鋼板ならびにその製造方法
JP5119903B2 (ja) * 2007-12-20 2013-01-16 Ｊｆｅスチール株式会社 高強度溶融亜鉛めっき鋼板および高強度合金化溶融亜鉛めっき鋼板の製造方法
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
JP4998756B2 (ja) * 2009-02-25 2012-08-15 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
JP4883216B2 (ja) * 2010-01-22 2012-02-22 Ｊｆｅスチール株式会社 加工性とスポット溶接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
JP5786319B2 (ja) * 2010-01-22 2015-09-30 Ｊｆｅスチール株式会社 耐バリ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

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
AUTORENKOLLEKTIV: "Spurenelemente im Stahl - Moeglichkeiten zur Beeinflussung im Smelzbetrieb", SPURENELEMENTE IN STAEHLEN, VERLAG STAHLEISEN, DUESSELDORF, DE, 1 January 1985 (1985-01-01), pages 19 - 22, XP002433212 *

Also Published As

Publication number Publication date
JP2011168877A (ja) 2011-09-01
WO2011090180A1 (fr) 2011-07-28
EP2527482A4 (fr) 2017-04-05
TWI433961B (zh) 2014-04-11
JP5786317B2 (ja) 2015-09-30
TW201139731A (en) 2011-11-16
EP2527482A1 (fr) 2012-11-28

Similar Documents

Publication Publication Date Title
EP2402470B1 (fr) Tôle en acier galvanisé à chaud à haute résistance présentant une excellente aptitude au façonnage et procédé de fabrication associé
EP2716773B1 (fr) Procédé de fabrication d'une feuille d'acier galvanisée par immersion à chaud à haute résistance ayant une excellente stabilité de qualité de matériau, une excellente aptitude au traitement et un excellent aspect de dépôt
EP2527482B1 (fr) Procédé de production d'une tôle en acier galvanisé au trempé à haute résistance présentant une excellente stabilité matérielle et une excellente aptitude au traitement
JP5967319B2 (ja) 高強度鋼板およびその製造方法
EP2327810B1 (fr) Feuille d'acier de résistance élevée et son procédé de fabrication
JP5834717B2 (ja) 高降伏比を有する溶融亜鉛めっき鋼板およびその製造方法
JP5967320B2 (ja) 高強度鋼板およびその製造方法
JP5765092B2 (ja) 延性と穴広げ性に優れた高降伏比高強度溶融亜鉛めっき鋼板およびその製造方法
WO2012147898A1 (fr) Tôle d'acier à résistance élevée présentant une excellente aptitude à la déformation et stabilité des propriétés du matériau et son procédé de fabrication
JP5786318B2 (ja) 疲労特性と穴拡げ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
WO2013051238A1 (fr) Tôle d'acier à haute résistance et procédé de fabrication associé
JP4883216B2 (ja) 加工性とスポット溶接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
JP2015113504A (ja) 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
EP3705592A1 (fr) Tôle d'acier laminée à froid à haute résistance, tôle d'acier plaquée à haute résistance, et leurs procédés de production
CN114585766A (zh) 高强度钢板及其制造方法
CN114585761A (zh) 高强度钢板及其制造方法
JP7006849B1 (ja) 鋼板、部材及びそれらの製造方法
EP4079882A1 (fr) Tôle d'acier, élément et procédés respectivement pour la production de ladite tôle d'acier et dudit élément
EP4043594B1 (fr) Tôle en acier hautement résistante ainsi que procédé de fabrication de celle-ci, et élément d'absorption de chocs
JP5988000B1 (ja) 高強度鋼板およびその製造方法

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: 20120720

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAX Request for extension of the european patent (deleted)
RIC1 Information provided on ipc code assigned before grant

Ipc: C21D 8/04 20060101ALI20170222BHEP

Ipc: C21D 8/02 20060101ALI20170222BHEP

Ipc: C22C 38/02 20060101ALI20170222BHEP

Ipc: C22C 38/00 20060101AFI20170222BHEP

Ipc: C22C 38/58 20060101ALI20170222BHEP

Ipc: C23C 2/02 20060101ALI20170222BHEP

Ipc: C22C 38/12 20060101ALI20170222BHEP

Ipc: C22C 38/04 20060101ALI20170222BHEP

Ipc: C22C 38/06 20060101ALI20170222BHEP

Ipc: C21D 9/46 20060101ALI20170222BHEP

Ipc: C23C 2/06 20060101ALI20170222BHEP

Ipc: C23C 2/28 20060101ALI20170222BHEP

Ipc: C22C 38/18 20060101ALI20170222BHEP

RA4 Supplementary search report drawn up and despatched (corrected)

Effective date: 20170302

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

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20180314

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

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

Free format text: STATUS: GRANT OF PATENT IS INTENDED

RIC1 Information provided on ipc code assigned before grant

Ipc: C22C 38/06 20060101ALI20190703BHEP

Ipc: C23C 2/02 20060101ALI20190703BHEP

Ipc: C22C 38/04 20060101ALI20190703BHEP

Ipc: C21D 8/04 20060101ALI20190703BHEP

Ipc: C21D 8/02 20060101ALI20190703BHEP

Ipc: C21D 9/46 20060101ALI20190703BHEP

Ipc: C22C 38/12 20060101ALI20190703BHEP

Ipc: C23C 2/06 20060101ALI20190703BHEP

Ipc: C22C 38/02 20060101ALI20190703BHEP

Ipc: C22C 38/00 20060101AFI20190703BHEP

Ipc: C23C 2/28 20060101ALI20190703BHEP

Ipc: C22C 38/18 20060101ALI20190703BHEP

INTG Intention to grant announced

Effective date: 20190806

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

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

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

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: DE

Ref legal event code: R096

Ref document number: 602011064215

Country of ref document: DE

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1217206

Country of ref document: AT

Kind code of ref document: T

Effective date: 20200115

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: NL

Ref legal event code: FP

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

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: 20200325

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: 20191225

Ref country code: NO

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: 20200325

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: 20200326

Ref country code: LT

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: 20191225

Ref country code: SE

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: 20191225

Ref country code: LV

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: 20191225

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

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

Ref country code: RS

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: 20191225

Ref country code: HR

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: 20191225

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

Ref country code: AL

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: 20191225

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

Ref country code: RO

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: 20191225

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: 20191225

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: 20200520

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: 20191225

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

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: 20191225

Ref country code: IS

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: 20200425

Ref country code: SM

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: 20191225

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602011064215

Country of ref document: DE

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

Effective date: 20191225

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20200131

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: 20200118

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: 20191225

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: 20191225

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

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1217206

Country of ref document: AT

Kind code of ref document: T

Effective date: 20191225

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

Ref country code: LI

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

Effective date: 20200131

Ref country code: CH

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

Effective date: 20200131

Ref country code: SI

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: 20191225

Ref country code: BE

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

Effective date: 20200131

26N No opposition filed

Effective date: 20200928

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

Ref country code: IE

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

Effective date: 20200118

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

Effective date: 20191225

Ref country code: AT

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: 20191225

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

Ref country code: PL

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: 20191225

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

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: 20191225

Ref country code: MT

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: 20191225

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: 20191225

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

Ref country code: MK

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: 20191225

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

Ref country code: NL

Payment date: 20221220

Year of fee payment: 13

Ref country code: GB

Payment date: 20221201

Year of fee payment: 13

Ref country code: FR

Payment date: 20221208

Year of fee payment: 13

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

Ref country code: DE

Payment date: 20221130

Year of fee payment: 13