EP4265763A1 - Hochfestes stahlblech mit hervorragender bearbeitbarkeit und verfahren zur herstellung davon - Google Patents

Hochfestes stahlblech mit hervorragender bearbeitbarkeit und verfahren zur herstellung davon Download PDF

Info

Publication number
EP4265763A1
EP4265763A1 EP21906929.1A EP21906929A EP4265763A1 EP 4265763 A1 EP4265763 A1 EP 4265763A1 EP 21906929 A EP21906929 A EP 21906929A EP 4265763 A1 EP4265763 A1 EP 4265763A1
Authority
EP
European Patent Office
Prior art keywords
steel sheet
less
balance
tensile strength
temperature
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.)
Pending
Application number
EP21906929.1A
Other languages
English (en)
French (fr)
Other versions
EP4265763A4 (de
Inventor
Jae-Hoon Lee
Sang-Ho Han
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.)
Posco Holdings Inc
Original Assignee
Posco Co Ltd
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 Posco Co Ltd filed Critical Posco Co Ltd
Publication of EP4265763A1 publication Critical patent/EP4265763A1/de
Publication of EP4265763A4 publication Critical patent/EP4265763A4/de
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • 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
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/84—Controlled slow cooling
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/001—Heat treatment of ferrous alloys containing Ni
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/002—Heat treatment of ferrous alloys containing Cr
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/007—Heat treatment of ferrous alloys containing Co
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • 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
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0236—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0273—Final recrystallisation annealing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—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
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • 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
    • C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
    • 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
    • C22C38/008—Ferrous alloys, e.g. steel alloys containing tin
    • 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
    • C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
    • 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
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • 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
    • C22C38/32—Ferrous alloys, e.g. steel alloys containing chromium with boron
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of manganese
    • C—CHEMISTRY; METALLURGY
    • 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
    • C21D2211/002—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
    • 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
    • C21D8/0421—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 characterised by the working steps
    • C21D8/0426—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/04—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
    • C21D8/0421—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 characterised by the working steps
    • C21D8/0436—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/04—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
    • C21D8/0447—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 characterised by the heat treatment
    • C21D8/0463—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 characterised by the heat treatment following hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/04—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
    • C21D8/0447—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 characterised by the heat treatment
    • C21D8/0473—Final recrystallisation annealing
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
    • C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets

Definitions

  • Patent Documents 1 and 2 As a technique for further improving the workability of a steel sheet, a method of utilizing tempered martensite is disclosed in Patent Documents 1 and 2. Since tempered martensite made by tempering hard martensite is softened martensite, there is a difference in strength between tempered martensite and existing untempered martensite (fresh martensite). Therefore, when fresh martensite is suppressed and tempered martensite is formed, the workability may increase.
  • a balance (B TE ) of tensile strength and elongation expressed by the following relational expression 2 satisfies 3.0*10 6 to 6.2*10 6 (MPa 2 % 1/2 )
  • a balance (B TH ) of tensile strength and a hole expansion ratio expressed by the following relational 3 expression satisfies 6.0*10 6 to 11.5*10 6 (MPa 2 % 1/2 )
  • a yield ratio evaluation index (I YR ) expressed by the following relational expression 4 satisfies 0.15 to 0.42:
  • B TE Tensile Strength TS , MPa 2 * Elongation El , % 1 / 2 ;
  • B TH Tensile Strength TS , MPa 2 * Hole Expansion Ratio HER , % 1 / 2 ;
  • I YR 1 ⁇ Yield Ratio YR .
  • a steel sheet that may be used for automobile parts and the like, and to a steel sheet having an excellent balance of tensile strength and ductility, an excellent balance of tensile strength and hole expansion ratio, and an excellent yield ratio evaluation index, and a method for manufacturing the same.
  • the present disclosure relates to a high strength steel sheet having excellent workability and a method for manufacturing the same, and exemplary embodiments of the present disclosure will hereinafter be described. Exemplary embodiments of the present disclosure may be modified into various forms, and it is not to be interpreted that the scope of the present disclosure is limited to exemplary embodiments described below. The present exemplary embodiments are provided in order to further describe the present disclosure in detail to those skilled in the art to which the present disclosure pertains.
  • the inventors of the present disclosure recognized that in a boron(B)-added transformation-induced plasticity (TRIP) steel comprising bainite, tempered martensite, fresh martensite and retained austenite, when the fractions of the tempered martensite, the fresh martensite, and the retained austenite are controlled to be within certain ranges, the contents of the boron (B) contained in the tempered martensite and the fresh martensite are controlled to be within certain ranges, and a shape and a size of the retained austenite are controlled to be within certain ranges, it is possible to simultaneously secure an excellent balance of tensile strength and ductility, an excellent balance of tensile strength and a hole expansion ratio, and an excellent yield ratio evaluation index. Based thereon, the present inventors have conceived of the present disclosure by devising a method such that excellent strength, excellent yield ratio, excellent ductility, and an excellent hole expansion ratio may be simultaneously provided.
  • TRIP transformation-induced plasticity
  • Carbon (C) is an unavoidable element for securing strength of a steel sheet, and is also an element for stabilizing retained austenite that contributes to the improvement in ductility of the steel sheet. Accordingly, in the present disclosure, 0.1% or more of carbon (C) may be added in order to achieve such an effect.
  • a preferable content of carbon (C) may be greater than 0.1%, may be 0.11% or more, and may be 0.12% or more.
  • an upper limit of the content of carbon (C) of the present disclosure may be limited to 0.25%.
  • the content of carbon (C) may be 0.24% or less, and a more preferable content of carbon (C) may be 0.23% or less.
  • Sulfur (S) is an element which is contained as an impurity to form MnS in a steel sheet and deteriorate ductility. Therefore, it is preferable that the content of sulfur (S) is 0.03% or less.
  • the steel sheet of the present disclosure has an alloy composition that may be additionally included in addition to the above-described alloy components, which will be described in detail below.
  • chromium (Cr) and molybdenum (Mo) are elements that not only suppress austenite decomposition during alloying treatment, but also stabilize austenite like manganese (Mn), in the present disclosure, one or more of chromium (Cr) and molybdenum (Mo) may be added in order to achieve such an effect.
  • the present disclosure may limit the contents of chromium (Cr) and molybdenum (Mo) to 3.0% or less, respectively.
  • antimony (Sb) and tin (Sn) are elements that improve plating wettability and plating adhesion of a steel sheet
  • one or more of antimony (Sb) and tin (Sn) may be added in order to achieve such an effect.
  • the present disclosure may limit the contents of antimony (Sb) and tin (Sn) to 0.5% or less, respectively.
  • Y yttrium
  • Hf hafnium
  • yttrium (Y) and hafnium (Hf) are elements that improve corrosion resistance of a steel sheet
  • one or more of the yttrium (Y) and hafnium (Hf) may be added in order to achieve such an effect.
  • the present disclosure may limit the contents of yttrium (Y) and hafnium (Hf) to 0.2% or less, respectively.
  • the present disclosure limits the ratio of the content of boron (B) contained in the fresh martensite to the content of boron (B) contained in the tempered martensite to be in a range of 0.03 to 0.55 as shown in relational expression 1, thereby securing a balance (TS 2 *EL 1/2 ) of tensile strength and elongation, a balance (TS 2 *HER 1/2 ) of tensile strength and a hole expansion ratio, and a yield ratio evaluation index (1-YR) targeted thereby.
  • a method for manufacturing a high strength steel sheet having excellent workability may comprises: heating (primarily heating) a cold-rolled steel sheet having a predetermined alloy composition to a temperature of 700°C at an average heating rate of 5°C/s or more, heating (secondarily heating) the primarily heated steel sheet to a temperature within a range of Ac3 to 920°C at an average heating rate of 5°C/s or less, and then maintaining (primarily maintaining) the secondarily heated steel sheet for 50 to 1200 seconds; cooling (primarily cooling) the primarily maintained steel sheet to a temperature within a range of 200 to 400°C at an average cooling rate of 1°C/s or more; heating (tertiarily heating) the primarily cooled steel sheet to a temperature within a range of 350 to 550°C at an average heating rate of 5°C/s or more, and then maintaining (secondarily maintaining) the tertiarily heated steel sheet for 50 seconds or more; and cooling (secondarily cooling) the secondarily maintained steel sheet to
  • the cold-rolled steel sheet is heated (primarily heated) to a temperature of 700°C at an average heating rate of 5°C/s or more, is heated (secondarily heated) to a temperature within a range of Ac3 to 920°C at an average heating rate of 5°C/s or less, and then is maintained (primarily maintained) for 50 to 1200 seconds.
  • tempered martensite When the primary cooling stop temperature is lower than 200°C, tempered martensite is excessively formed, and retained austenite becomes insufficient, whereby a balance (TS 2 *EL 1/2 ) of tensile strength and elongation and a balance (TS 2 *HER 1/2 ) of tensile strength and a hole expansion ratio of the steel sheet may be lowered.
  • the primary cooling stop temperature exceeds 400°C, bainite is excessively formed, and tempered martensite becomes insufficient, whereby a balance (TS 2 *EL 1/2 ) of tensile strength and elongation and a balance (TS 2 *HER 1/2 ) of tensile strength and a hole expansion ratio of the steel sheet may be lowered.
  • Tensile strength (TS) and elongation (El) were evaluated through a tensile test, and the tensile strength (TS) and the elongation (El) were measured by evaluating the specimens collected in accordance with JIS No. 5 standard based on a 90° direction with respect to a rolling direction of a rolled sheet.
  • the secondary average heating rate was more than 5°C/s, so that lump austenite was formed, and boron (B) was not concentrated into tempered martensite.
  • [B] FM /[B] TM was more than 0.55
  • a yield ratio evaluation index (I YR ) was more than 0.42
  • a balance (B TE ) of tensile strength and elongation was less than 3.0*10 6
  • a balance (B TH ) of tensile strength and a hole expansion ratio was less than 6.0*10 6 , in specimen 3.
  • the primary cooling stop temperature was more than 400°C, so that a fraction of bainite was excessive, and a fraction of tempered martensite was insufficient.
  • a balance (B TE ) of tensile strength and elongation was less than 3.0*10 6
  • a balance (B TH ) of tensile strength and a hole expansion ratio was less than 6.0*10 6 , in specimen 7.
  • specimen 9 the secondary maintaining temperature was more than 550°C, so that a fraction of retained austenite was insufficient. As a result, a balance (B TE ) of tensile strength and elongation was less than 3.0*10 6 , in specimen 9.
  • the secondary maintaining time was less than 50 seconds, so that a fraction of tempered martensite was excessive, and a fraction of retained austenite was insufficient.
  • a balance (B TE ) of tensile strength and elongation was less than 3.0*10 6
  • a balance (B TH ) of tensile strength and a hole expansion ratio was less than 6.0*10 6 , in specimen 10.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
EP21906929.1A 2020-12-17 2021-12-01 Hochfestes stahlblech mit hervorragender bearbeitbarkeit und verfahren zur herstellung davon Pending EP4265763A4 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020200177474A KR102485004B1 (ko) 2020-12-17 2020-12-17 가공성이 우수한 고강도 강판 및 그 제조방법
PCT/KR2021/017989 WO2022131624A1 (ko) 2020-12-17 2021-12-01 가공성이 우수한 고강도 강판 및 그 제조방법

Publications (2)

Publication Number Publication Date
EP4265763A1 true EP4265763A1 (de) 2023-10-25
EP4265763A4 EP4265763A4 (de) 2024-06-19

Family

ID=82059230

Family Applications (1)

Application Number Title Priority Date Filing Date
EP21906929.1A Pending EP4265763A4 (de) 2020-12-17 2021-12-01 Hochfestes stahlblech mit hervorragender bearbeitbarkeit und verfahren zur herstellung davon

Country Status (6)

Country Link
US (1) US20240011118A1 (de)
EP (1) EP4265763A4 (de)
JP (1) JP7712366B2 (de)
KR (1) KR102485004B1 (de)
CN (1) CN116601320B (de)
WO (1) WO2022131624A1 (de)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR102485012B1 (ko) * 2020-12-17 2023-01-04 주식회사 포스코 가공성이 우수한 고강도 강판 및 그 제조방법

Family Cites Families (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4510488B2 (ja) 2004-03-11 2010-07-21 新日本製鐵株式会社 成形性および穴拡げ性に優れた溶融亜鉛めっき複合高強度鋼板およびその製造方法
JP4901617B2 (ja) 2007-07-13 2012-03-21 新日本製鐵株式会社 引張強度が７００ＭＰａ以上で耐食性、穴拡げ性および延性に優れた合金化溶融亜鉛めっき高強度鋼板及びその製造方法
JP5136609B2 (ja) * 2010-07-29 2013-02-06 Ｊｆｅスチール株式会社 成形性および耐衝撃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
WO2013018740A1 (ja) * 2011-07-29 2013-02-07 新日鐵住金株式会社 耐衝撃特性に優れた高強度鋼板およびその製造方法、高強度亜鉛めっき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
JP5821912B2 (ja) * 2013-08-09 2015-11-24 Ｊｆｅスチール株式会社 高強度冷延鋼板およびその製造方法
WO2015088523A1 (en) * 2013-12-11 2015-06-18 ArcelorMittal Investigación y Desarrollo, S.L. Cold rolled and annealed steel sheet
EP3101147B1 (de) * 2014-01-29 2018-08-15 JFE Steel Corporation Hochfestes kaltgewalztes stahlblech und verfahren zur herstellung davon
JP6295893B2 (ja) * 2014-08-29 2018-03-20 新日鐵住金株式会社 耐水素脆化特性に優れた超高強度冷延鋼板およびその製造方法
JP6586776B2 (ja) 2015-05-26 2019-10-09 日本製鉄株式会社 成形性に優れた高強度鋼板及びその製造方法
BR112017027412B1 (pt) * 2015-06-30 2021-07-06 Nippon Steel Corporation Chapa de aço laminada a frio, chapa de aço galvanizada por imersão a quente e chapa de aço galvanizada
JP6762868B2 (ja) * 2016-03-31 2020-09-30 株式会社神戸製鋼所 高強度鋼板およびその製造方法
MX2019009599A (es) * 2017-02-13 2019-10-14 Jfe Steel Corp Lamina de acero de alta resistencia y metodo para producir la misma.
WO2018189950A1 (ja) * 2017-04-14 2018-10-18 Ｊｆｅスチール株式会社 鋼板およびその製造方法
JP6849536B2 (ja) * 2017-05-31 2021-03-24 株式会社神戸製鋼所 高強度鋼板およびその製造方法
WO2019092481A1 (en) * 2017-11-10 2019-05-16 Arcelormittal Cold rolled steel sheet and a method of manufacturing thereof
KR102276741B1 (ko) * 2018-09-28 2021-07-13 주식회사 포스코 구멍확장성이 높은 고강도 냉연강판, 고강도 용융아연도금강판 및 이들의 제조방법
WO2020067752A1 (ko) * 2018-09-28 2020-04-02 주식회사 포스코 구멍확장성이 높은 고강도 냉연강판, 고강도 용융아연도금강판 및 이들의 제조방법
EP3845673A4 (de) * 2018-10-17 2021-07-14 JFE Steel Corporation Stahlblech und herstellungsverfahren dafür
WO2020104437A1 (en) * 2018-11-19 2020-05-28 Ssab Technology Ab High strength steel product and method of manufacturing the same
KR102164092B1 (ko) * 2018-12-19 2020-10-13 주식회사 포스코 버링성이 우수한 고강도 냉연강판 및 합금화 용융아연도금강판
KR102599376B1 (ko) * 2019-02-06 2023-11-09 닛폰세이테츠 가부시키가이샤 용융 아연 도금 강판 및 그 제조 방법
KR102485012B1 (ko) * 2020-12-17 2023-01-04 주식회사 포스코 가공성이 우수한 고강도 강판 및 그 제조방법
KR102485009B1 (ko) * 2020-12-17 2023-01-04 주식회사 포스코 가공성이 우수한 고강도 강판 및 그 제조방법
KR102485013B1 (ko) * 2020-12-17 2023-01-04 주식회사 포스코 가공성이 우수한 고강도 강판 및 그 제조방법

Also Published As

Publication number Publication date
US20240011118A1 (en) 2024-01-11
CN116601320A (zh) 2023-08-15
WO2022131624A1 (ko) 2022-06-23
KR102485004B1 (ko) 2023-01-04
JP2024500743A (ja) 2024-01-10
EP4265763A4 (de) 2024-06-19
CN116601320B (zh) 2025-11-04
KR20220087100A (ko) 2022-06-24
JP7712366B2 (ja) 2025-07-23

Similar Documents

Publication Publication Date Title
US12252759B2 (en) High strength steel sheet having excellent workability and method for manufacturing same
US12509751B2 (en) High strength steel sheet having excellent workability and method for manufacturing same
JP7734747B2 (ja) 加工性に優れた高強度鋼板及びその製造方法
EP4265771A1 (de) Hochfestes stahlblech mit hervorragender bearbeitbarkeit und verfahren zur herstellung davon
CN113227427A (zh) 延展性和加工性优异的高强度钢板及其制造方法
JP7442645B2 (ja) 加工性に優れた高強度鋼板及びその製造方法
US12492444B2 (en) High strength steel sheet having superior workability and method for manufacturing same
KR20220087170A (ko) 가공성이 우수한 고강도 강판 및 그 제조방법
JP7712366B2 (ja) 加工性に優れた高強度鋼板及びその製造方法
US12454734B2 (en) High strength steel sheet having excellent workability and method for manufacturing same
US20230031278A1 (en) High strength steel sheet having excellent workability and method for manufacturing same
KR20220087156A (ko) 가공성이 우수한 고강도 강판 및 그 제조방법
EP4079902B1 (de) Hochfestes stahlblech mit hoher bearbeitbarkeit und verfahren zu seiner herstellung
JP7554828B2 (ja) 加工性に優れた高強度鋼板及びその製造方法
EP4079901A1 (de) Hochfestes stahlblech mit hoher bearbeitbarkeit und verfahren zu seiner herstellung
EP4079899A2 (de) Hochfestes stahlblech mit hervorragender verarbeitbarkeit und verfahren zu seiner herstellung

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

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

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

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20230622

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

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
A4 Supplementary search report drawn up and despatched

Effective date: 20240522

RIC1 Information provided on ipc code assigned before grant

Ipc: C21D 1/84 20060101ALI20240515BHEP

Ipc: C21D 8/02 20060101ALI20240515BHEP

Ipc: C21D 9/46 20060101ALI20240515BHEP

Ipc: C22C 38/60 20060101ALI20240515BHEP

Ipc: C22C 38/06 20060101ALI20240515BHEP

Ipc: C22C 38/04 20060101ALI20240515BHEP

Ipc: C22C 38/02 20060101ALI20240515BHEP

Ipc: C22C 38/00 20060101AFI20240515BHEP