EP3822384B1 - Acier inoxydable austénitique ayant une résistance améliorée - Google Patents

Acier inoxydable austénitique ayant une résistance améliorée Download PDF

Info

Publication number
EP3822384B1
EP3822384B1 EP19849274.6A EP19849274A EP3822384B1 EP 3822384 B1 EP3822384 B1 EP 3822384B1 EP 19849274 A EP19849274 A EP 19849274A EP 3822384 B1 EP3822384 B1 EP 3822384B1
Authority
EP
European Patent Office
Prior art keywords
stainless steel
austenitic stainless
content
phase
austenite
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
EP19849274.6A
Other languages
German (de)
English (en)
Other versions
EP3822384A4 (fr
EP3822384B8 (fr
EP3822384A1 (fr
Inventor
Jae-Hwa Lee
Gyu Jin Jo
Young Tae Kim
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 Holdings Inc
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 Holdings Inc filed Critical Posco Holdings Inc
Publication of EP3822384A1 publication Critical patent/EP3822384A1/fr
Publication of EP3822384A4 publication Critical patent/EP3822384A4/fr
Application granted granted Critical
Publication of EP3822384B1 publication Critical patent/EP3822384B1/fr
Publication of EP3822384B8 publication Critical patent/EP3822384B8/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
    • C—CHEMISTRY; METALLURGY
    • 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
    • C21D1/26—Methods of 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/004—Heat treatment of ferrous alloys containing Cr and 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
    • 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
    • C21D8/0247—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
    • 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
    • C22C38/002—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
    • C22C38/02—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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/54—Ferrous alloys, e.g. steel alloys containing chromium with nickel with boron
    • 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

Definitions

  • the present disclosure relates to austenitic stainless steel, in particular, to austenitic stainless steel with improved strength while securing elongation and corrosion resistance.
  • Stainless steel refers to steel that has strong corrosion resistance by suppressing corrosion, a weak point of carbon steel.
  • stainless steel is classified according to its chemical composition or metal structure. According to the metal structure, stainless steel can be classified into austenite, ferrite, martensite and dual phase.
  • austenitic stainless steel is a steel containing a large amount of chromium (Cr) and nickel (Ni), and is most commonly used.
  • 316L stainless steel has a component based on 16 ⁇ 18% Cr, 10 ⁇ 14% Ni, and 2 ⁇ 3% molybdenum (Mo), is applied in various industrial fields by securing corrosion resistance and molding properties.
  • 216 stainless steel is basically a steel containing a large amount of Mn of 7% or more in order to reduce the material price by reducing the Ni content to a certain amount or less, and to secure the stability of the austenite phase according to the amount of Ni reduction. It contains 17.5 ⁇ 22% Cr, 5 ⁇ 7% Ni, 7.5 ⁇ 9% Mn and 2 ⁇ 3% Mo in percent (%) by weight.
  • 216 stainless steel can secure a level of corrosion resistance similar to that of 316L stainless steel, but due to the generation of a large amount of Mn fume during the steel making process due to the addition of a large amount of Mn, not only environmental improvement is required, but also the production of steel making inclusions (MnS) results in a decrease in productivity in the manufacturing process and a decrease in the surface quality of the final material.
  • MnS steel making inclusions
  • duplex stainless steel is a substitute for 316L stainless steel.
  • Duplex stainless steel is a stainless steel having a microstructure in which austenite phase and ferrite phase are mixed. Specifically, the austenite phase and the ferrite phase each exist in a volume fraction of about 35 to 65%, showing the characteristics of both austenitic stainless steel and ferritic stainless steel.
  • Duplex stainless steel secures corrosion resistance equivalent to 316L stainless steel, and has low Ni content, making it economical and easy to secure high strength. Therefore, it is in the spotlight as a steel for industrial facilities such as desalination facilities, pulp, paper, and chemical facilities that require corrosion resistance.
  • Embodiments of the present disclosure are intended to provide an austenitic stainless steel with improved strength while securing elongation and corrosion resistance of the existing 316L stainless steel level.
  • an austenitic stainless steel with improved strength includes, in percent (%) by weight of the entire composition, C: 0.02 to 0.14%, Si: 0.2 to 0.6%, S: less than 0.01%, Mn: 2.0 to 4.5%, Ni: 2.5 to 5.0%, Cr: 19.0 to 22.0%, Cu: 1.0 to 3.0%, Mo: less than 1.0%, N: 0.25 to 0.40%, optionally B: 0.001 to 0.005% and Ca: 0.001 to 0.003%, the remainder of iron (Fe) and inevitable impurities, and the Solubility of Nitrogen in Liquid (SNL) value represented by the following equation (1) is equal to or greater than the content of N.
  • the C+N is 0.5% or less (excluding 0).
  • the Md 30 value represented by the following equation (2) may satisfy -50 or less.
  • Md 30 551 ⁇ 462 ⁇ C + N ⁇ 9.2 ⁇ Si ⁇ 8.1 ⁇ Mn ⁇ 13.7 ⁇ Cr ⁇ 29 ⁇ Ni + Cu ⁇ 8.5 ⁇ Mo (Here, C, N, Si, Mn, Cr, Ni, Cu, and Mo mean the content (% by weight) of each element.)
  • the Pitting Resistance Equivalent Number (PREN) represented by the following equation (4) may satisfy 22 or more.
  • PREN 16 + 3.3 Mo + 16 N ⁇ 0.5 Mn (Here, Mo, N, and Mn mean the content (% by weight) of each element.)
  • the yield strength (0.2 off-set) may be 400 to 450 MPa and the tensile strength may be 700 to 850 MPa.
  • the elongation may be 35% or more.
  • FIG. 1 is a graph for illustrating a correlation between Thermocalc. calculation result and a regression equation applied value for deriving Solubility of Nitrogen in Liquid (SNL) value of austenitic stainless steel according to an embodiment of the present disclosure.
  • An austenitic stainless steel includes, in percent (%) by weight of the entire composition, C: 0.02 to 0.14%, Si: 0.2 to 0.6%, P: less than 0.1%, S: less than 0.01%, Mn: 2.0 to 4.5%, Ni: 2.5 to 5.0%, Cr: 19.0 to 22.0%, Cu: 1.0 To 3.0%, Mo: less than 1.0%, N: 0.25 to 0.40%, optionally B: 0.001 to 0.005% and Ca: 0.001 to 0.003%, the remainder of iron (Fe) and inevitable impurities.
  • the content of C is 0.02 to 0.14%.
  • Carbon (C) is an element effective in stabilizing the austenite phase, but when the content is low, 0.02% or more may be added as additional austenite stabilizing elements are required. However, if the content is excessive, workability may be lowered due to the solid solution strengthening effect. In addition, if the content is excessive, it may adversely affect the ductility, toughness, corrosion resistance, etc. by inducing grain boundary precipitation of Cr carbide due to latent heat after hot-rolled coiling and the heat-affected zone of the weld, so the upper limit may be limited to 0.14%.
  • the content of Si is 0.2 to 0.6%.
  • Si serves as a deoxidizing agent during the steelmaking process and is an effective element to improve corrosion resistance and can be added by 0.2% or more.
  • Si is an element that is effective in stabilizing the ferrite phase, and when excessively added, it promotes the formation of delta ferrite in the casting slab, thereby reducing hot workability.
  • the ductility/toughness of the steel material due to the solid solution strengthening effect may be lowered, and thus the upper limit thereof may be limited to 0.6%.
  • the content of Mn is 2.0 to 4.5%.
  • Manganese (Mn) is an austenite phase stabilizing element that is added instead of nickel (Ni) in the present disclosure. It is effective in improving cold rolling properties by suppressing the generation of strain-induced martensite, and is an element that increases the solubility of nitrogen (N) during a steelmaking process to be described later, and may be added by 2.0% or more. However, if the content is excessive, Mn may reduce the ductility, toughness, and corrosion resistance of steel materials as it causes an increase in S-based inclusions (MnS), and thus the upper limit thereof may be limited to 4.5%.
  • the content of Ni is 2.5 to 5.0%.
  • Nickel (Ni) is a strong austenite phase stabilizing element and is essential to secure good hot workability and cold workability. In particular, even when a certain amount of Mn is added, it is essential to add 2.5% or more. However, since Ni is an expensive element, it causes an increase in raw material cost when a large amount is added. Accordingly, the upper limit can be limited to 5.0% in consideration of both cost and efficiency of the steel.
  • the content of Cr is 19 to 22%.
  • chromium (Cr) is a ferrite stabilizing element, it is effective in suppressing the formation of martensite phase, and is a basic element that secures corrosion resistance required for stainless steel.
  • 19% or more may be added as an element that increases the solubility of nitrogen (N) during a steelmaking process to be described later.
  • N solubility of nitrogen
  • ⁇ delta
  • austenite stabilizing elements such as Ni and Mn
  • the content of P is less than 0.1%.
  • phosphorus (P) lowers corrosion resistance or hot workability, its upper limit may be limited to 0.1%.
  • the content of S is less than 0.01%.
  • sulfur (S) lowers corrosion resistance or hot workability, its upper limit may be limited to 0.01%.
  • the content of Cu is 1.0 to 3.0%.
  • Copper (Cu) is an austenite phase stabilizing element added instead of nickel (Ni) in the present disclosure, and improves formability by improving corrosion resistance in a reducing environment and reducing Stacking Fault Energy (SFE). 1.0% or more may be added to sufficiently express such an effect. However, if the content is excessive, the upper limit may be limited to 3.0% because it may increase the material cost as well as lower the hot workability.
  • the content of Mo is less than 1.0%.
  • Molybdenum (Mo) is an effective element in improving the corrosion resistance of stainless steel by modifying the passive film.
  • Mo is an expensive element, when a large amount of Mo is added, it causes an increase in raw material cost and has a problem of deteriorating hot workability. Accordingly, in consideration of the cost-efficiency and hot workability of the steel, the upper limit can be limited to 1.0%.
  • the content of N is 0.25 to 0.40%.
  • Nitrogen (N) is an element that is effective in improving corrosion resistance and is a strong austenite stabilizing element. Therefore, nitrogen alloying can reduce material cost by enabling lower use of Ni, Cu, and Mn. 0.25% or more may be added to sufficiently express this effect. However, if the content is excessive, since workability and moldability may be deteriorated due to the solid solution strengthening effect, the upper limit may be limited to 0.40%.
  • the content of C+N is 0.5% or less.
  • C and N are elements that are effective for improving strength, but when the content is excessive, there is a problem of lowering the workability, and the upper limit of the total may be limited to 0.5%.
  • the austenitic stainless steel with improved strength according to an embodiment of the present disclosure may further include one or more of B: 0.001 to 0.005 and Ca: 0.001 to 0.003%.
  • the content of B is 0.001 to 0.005%.
  • Boron (B) is an element effective in securing good surface quality by suppressing the occurrence of cracks during casting, and can be added by 0.001% or more. However, if the content is excessive, nitride (BN) may be formed on the product surface during the annealing/pickling process, thereby reducing the surface quality. Therefore, the upper limit can be limited to 0.005%.
  • the content of Ca is 0.001 to 0.003%.
  • Calcium (Ca) is an element that improves product cleanliness by suppressing the formation of MnS steel-making inclusions generated at grain boundaries when high Mn is contained, and can be added by 0.001% or more. However, if the content is excessive, it may cause a decrease in hot workability and a decrease in product surface quality due to formation of Ca-based inclusions, and the upper limit may be limited to 0.003%.
  • the remaining component of the present disclosure is iron (Fe).
  • Fe iron
  • unintended impurities from the raw material or the surrounding environment may inevitably be mixed in the normal manufacturing process, this cannot be excluded. Since these impurities are known to anyone of ordinary skill in the manufacturing process, all the contents are not specifically mentioned in the present specification.
  • the content of N that can be dissolved in the molten metal temperature at 1150°C is derived according to the amount of each alloy element (C, Si, Mn, Ni, Cr, Cu, Mo) added.
  • FIG. 1 is a graph for illustrating a correlation between Thermocalc. calculation result and a regression equation applied value for deriving Solubility of Nitrogen in Liquid (SNL) value of austenitic stainless steel according to an embodiment of the present disclosure.
  • N solubility limit (The.)
  • SNL Solubility of Nitrogen in Liquid regression equation of Equation (1) was derived based on the calculated value of Thermocalc. according to the component change.
  • SNL ⁇ 0.188 ⁇ 0.0423 ⁇ C ⁇ 0.0517 ⁇ Si + 0.012 ⁇ Mn + 0.0048 ⁇ Ni + 0.0252 ⁇ Cr ⁇ 0.00906 ⁇ Cu + 0.00021 ⁇ Mo
  • the SNL value is greater than or equal to N content. In this way, when the SNL value was set higher than the N content to increase the nitrogen solubility limit, it was confirmed that the steelmaking operation of the target alloy component was performed satisfactorily.
  • austenitic stainless steel In the case of austenitic stainless steel, it is applied to products that require a beautiful surface. For products that require a beautiful surface, it is common to perform a bright annealing on cold-rolled materials.
  • This bright annealing is a heat treatment technology that keeps the surface bright and beautiful without changing the color and properties of the surface by preventing reoxidation occurring during the heat treatment process of the stainless steel cold rolled material by performing heat treatment on the stainless steel cold rolled material in a reducing atmosphere (Dew point -40 ⁇ -60°C) using nitrogen (N 2 ), hydrogen (H 2 ), etc.
  • Bright annealing using hydrogen as the atmosphere gas used for bright annealing is the most common, because it is most widely used for suppressing discoloration of the surface as well as high heat capacity.
  • the hydrogen atoms penetrating into the surface layer are naturally bake-out after a certain period of time at room temperature for ferrite or martensite phase, which are general BCC and BCT structures, and do not significantly affect the physical properties.
  • This hydrogen atom is known as a factor causing hydrogen embrittlement. Hydrogen atoms trapped in the material due to some processing or deformation change to the state of hydrogen molecules (gas), and when a certain pressure is reached, it acts as a starting point of cracks under a certain load, causing a decrease in elongation.
  • the beautiful surface quality and workability can be secured through bright annealing only by controlling the amount of martensite phase formed on the surface by work hardening together with the alloy component.
  • the Md30 value expressed by the following equation (2) satisfies the range of -50°C or less.
  • Md 30 551 ⁇ 462 ⁇ C + N ⁇ 9.2 ⁇ Si ⁇ 8.1 ⁇ Mn ⁇ 13.7 ⁇ Cr ⁇ 29 ⁇ Ni + Cu ⁇ 8.5 ⁇ Mo
  • martensitic transformation occurs by plastic working at a temperature of the martensitic transformation initiation temperature (Ms) or more.
  • the upper limit temperature that causes phase transformation by such processing is represented by the Md value, and is a criterion of the degree to which phase transformation occurs by processing.
  • the temperature (°C) at which 50% phase transformation to martensite occurs when 30% strain is applied is defined as Md 30 .
  • Md 30 value is used as an index to determine the austenite stability of austenitic stainless steel, and can be calculated through the Nohara regression equation expressed by the equation (2).
  • Creq / Nieq The degree to which each alloy component affects the phase balance can be calculated through Creq and Nieq, and the phase generated at room temperature can be predicted through the Creq/Nieq ratio expressed as in the equation (3) below.
  • Nieq Ni +0.5 ⁇ Mn +30 ⁇ (C +N) +0.5 ⁇ Cu.
  • PREN Pitting Resistance Equivalent Number
  • PREN is generally used to influence Cr, Mo, and N, but for steel grades with relatively high Mn content, since it is necessary to consider the influence of Mn as well, the following equation (4) was derived from the present disclosure.
  • a slab having a thickness of 200 mm was prepared by melting an ingot, heated at 1,240°C for 2 hours, and then hot-rolled to prepare a hot-rolled steel sheet having a thickness of 3 mm.
  • comparative example 1 which corresponds to the composition of general 316L stainless steel, it represents the tissue composed of the austenite phase, and it can be seen that the PREN value is 22 or higher.
  • the mechanical property evaluation result showed a yield strength of 220 MPa and a tensile strength of 540 MPa.
  • This corresponds to the physical properties of generally widely used soft austenitic stainless steel, and thus has a problem that is difficult to apply to materials requiring high strength.
  • the Md 30 value is -5°C, and hydrogen embrittlement is likely to occur when producing bright annealing materials with beautiful surfaces in the future.
  • the N solubility limit which is greatly affected by the Cr content, is low, the amount of N added is 0.21%, and the nitrogen factor of the PREN value cannot be maximized, making it difficult to secure pitting resistance of 316L level.
  • the C+N content is 0.5%, exceeding 0.5%, which is the upper limit of the present disclosure, indicating hard mechanical properties and elongation of less than 35%.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)
  • Materials For Medical Uses (AREA)

Claims (7)

  1. Acier inoxydable austénitique à résistance améliorée comprenant, en pourcentage (%) en poids de la composition totale, C : 0,02 à 0,14 %, Si : 0,2 à 0,6 %, S : moins de 0,01 %, Mn : 2,0 à 4,5 %, Ni : 2,5 à 5,0 %, Cr : 19,0 à 22,0 %, Cu : 1,0 à 3,0 %, Mo : moins de 1,0 %, N : 0,25 à 0,40 %, éventuellement B : 0,001 à 0,005 % et Ca : 0,001 à 0,003 %, le reste en fer (Fe) et des impuretés inévitables, et
    la valeur de solubilité de l'azote dans le liquide (SNL) représentée par l'équation (1) suivante étant égale ou supérieure à la teneur en N. SNL = − 0,188 − 0,0423 × C − 0,0517 × Si + 0,012 × Mn + 0,0048 × Ni + 0,0252 × Cr − 0,00906 × Cu + 0,00021 × Mo
    Figure imgb0017
     (Ici, C, Si, Mn, Ni, Cr, Cu et Mo signifient la teneur (% en poids) de chaque élément.)
  2. Acier inoxydable austénitique selon la revendication 1, dans lequel le C + N est de 0,5 % ou moins (à l'exclusion de 0).
  3. Acier inoxydable austénitique selon la revendication 1, dans lequel la valeur Md30 représentée par l'équation suivante (2) satisfait -50 ou moins. Md 30 = 551 − 462 × C + N − 9,2 × Si − 8,1 × Mn − 13,7 × Cr − 29 × Ni + Cu − 8,5 × Mo
    Figure imgb0018
     (Ici, C, N, Si, Mn, Cr, Ni, Cu et Mo signifient la teneur (% en poids) de chaque élément.)
  4. Acier inoxydable austénitique selon la revendication 1, dans lequel l'acier inoxydable austénitique satisfait l'équation suivante (3). Creq / Nieq ≤ 1,8
    Figure imgb0019
     (Ici, Creq = Cr + Mo + 1,5 × Si, Nieq = Ni + 0,5 × Mn + 30 × (C + N) + 0,5 × Cu.)
  5. Acier inoxydable austénitique selon la revendication 1, dans lequel le nombre équivalent de résistance à corrosion par piqûres (PREN) représenté par l'équation suivante (4) satisfait 22 ou plus. PREN = 16 + 3,3 Mo + 16 N − 0,5 Mn
    Figure imgb0020
     (Ici, Mo, N et Mn signifient la teneur (% en poids) de chaque élément.)
  6. Acier inoxydable austénitique selon la revendication 1, dans lequel la limite d'élasticité (décalage de 0,2) est de 400 à 450 MPa et la résistance à la traction est de 700 à 850 MPa.
  7. Acier inoxydable austénitique selon la revendication 1, dans lequel l'allongement est de 35 % ou plus.
EP19849274.6A 2018-08-13 2019-08-08 Acier inoxydable austénitique ayant une résistance améliorée Active EP3822384B8 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1020180094523A KR102160735B1 (ko) 2018-08-13 2018-08-13 강도가 향상된 오스테나이트계 스테인리스강
PCT/KR2019/009977 WO2020036370A1 (fr) 2018-08-13 2019-08-08 Acier inoxydable austénitique ayant une résistance améliorée

Publications (4)

Publication Number Publication Date
EP3822384A1 EP3822384A1 (fr) 2021-05-19
EP3822384A4 EP3822384A4 (fr) 2021-09-01
EP3822384B1 true EP3822384B1 (fr) 2023-01-18
EP3822384B8 EP3822384B8 (fr) 2023-02-22

Family

ID=69525604

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19849274.6A Active EP3822384B8 (fr) 2018-08-13 2019-08-08 Acier inoxydable austénitique ayant une résistance améliorée

Country Status (6)

Country Link
US (1) US20210292877A1 (fr)
EP (1) EP3822384B8 (fr)
KR (1) KR102160735B1 (fr)
CN (1) CN112789365B (fr)
FI (1) FI3822384T3 (fr)
WO (1) WO2020036370A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113151736A (zh) * 2021-01-28 2021-07-23 中航上大高温合金材料有限公司 一种耐腐蚀双相不锈钢及其制备方法

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000026428A1 (fr) * 1998-11-02 2000-05-11 Crs Holdings, Inc. Acier inoxydable austenitique cr-mn-ni-cu
JP3696552B2 (ja) * 2001-04-12 2005-09-21 日新製鋼株式会社 加工性，冷間鍛造性に優れた軟質ステンレス鋼板
EP2562285B1 (fr) * 2004-01-29 2017-05-03 JFE Steel Corporation Acier inoxydable austénitique-ferritique
US8337749B2 (en) * 2007-12-20 2012-12-25 Ati Properties, Inc. Lean austenitic stainless steel
MX2010005668A (es) * 2007-12-20 2010-06-03 Ati Properties Inc Acero inoxidable austenitico delgado resistente a la corrosion.
KR101056235B1 (ko) * 2008-11-25 2011-08-11 주식회사 포스코 오스테나이트계 스테인리스강 냉연제품의 재질특성 예측방법
SE533635C2 (sv) * 2009-01-30 2010-11-16 Sandvik Intellectual Property Austenitisk rostfri stållegering med låg nickelhalt, samt artikel därav
KR20120132691A (ko) * 2010-04-29 2012-12-07 오또꿈뿌 오와이제이 높은 성형성을 구비하는 페라이트-오스테나이트계 스테인리스 강의 제조 및 사용 방법
ES2885758T3 (es) * 2012-01-20 2021-12-15 Solu Stainless Oy Procedimiento para la fabricación de un producto de acero inoxidable austenítico
JP2014001422A (ja) 2012-06-18 2014-01-09 Nippon Steel & Sumitomo Metal オーステナイト系ステンレス鋼板およびその製造方法
CN103627970A (zh) * 2013-10-30 2014-03-12 振石集团东方特钢股份有限公司 一种含钒奥氏体不锈钢
FI125105B (en) * 2013-11-04 2015-06-15 Outokumpu Oy Grain boundary corrosion resistant austenitic stainless steel and method for its production
KR20150074697A (ko) * 2013-12-24 2015-07-02 주식회사 포스코 저 니켈 함유 스테인리스강
JP6438253B2 (ja) 2014-09-26 2018-12-12 エア・ウォーターＮｖ株式会社 遊技用鋼球およびその製造方法
JP6763759B2 (ja) * 2015-11-20 2020-09-30 日本精線株式会社 磁気特性に優れた二相系のステンレス鋼線、及び篩用、ネットコンベア用又はフィルタ用の磁性金網製品
KR101952808B1 (ko) * 2017-08-22 2019-02-28 주식회사포스코 열간가공성 및 내수소취성이 우수한 저Ni 오스테나이트계 스테인리스강

Also Published As

Publication number Publication date
KR102160735B1 (ko) 2020-09-28
EP3822384A4 (fr) 2021-09-01
WO2020036370A1 (fr) 2020-02-20
EP3822384B8 (fr) 2023-02-22
CN112789365A (zh) 2021-05-11
EP3822384A1 (fr) 2021-05-19
FI3822384T3 (fi) 2023-03-20
US20210292877A1 (en) 2021-09-23
CN112789365B (zh) 2022-09-27
KR20200018995A (ko) 2020-02-21

Similar Documents

Publication Publication Date Title
US20190226068A1 (en) Process for manufacturing hot-rolled plate, strip or coil made of duplex stainless steel
EP2540854B1 (fr) Feuille d'acier laminée à froid de super-haute résistance ayant d'excellentes propriétés de flexion
KR101635008B1 (ko) 용접 열영향부 ctod 특성이 우수한 후육 고장력강 및 그의 제조 방법
EP2804962B1 (fr) Procede de fabrication d'un acier inoxidable austenitique
KR100263365B1 (ko) 면내이방성이 작고 내리징성이 우수한 페라이트계 스텐레스강판및 그 제조방법
RU2593567C2 (ru) Высокопрочная стальная полоса с высокой ударной вязкостью и пределом текучести 700 мпа и способ ее производства
KR20170066612A (ko) 재질 균일성이 우수한 후육 고인성 고장력 강판 및 그 제조 방법
JP5195413B2 (ja) 曲げ加工性及び靭性の異方性に優れた高強度熱延鋼板及びその製造方法
EP3674434A1 (fr) Acier inoxydable austénitique à faible teneur en ni présentant d'excellentes propriétés d'ouvrabilité à chaud et de résistance à la fragilisation par l'hydrogène
EP3631032A1 (fr) Bande d'acier résistant à l'usure, abrasive, laminée à chaud, à résistance élevée
KR102634503B1 (ko) 열간 압연 강 및 그 제조 방법
EP3722448A1 (fr) Acier riche en mn, et procédé de fabrication de celui-ci
US11959157B2 (en) High-Mn steel and method of producing same
KR20150038601A (ko) 성형 가공성이 우수한 페라이트계 스테인리스 강판
EP3822384B1 (fr) Acier inoxydable austénitique ayant une résistance améliorée
KR20190044689A (ko) 강판
JP2016113670A (ja) フェライト系ステンレス鋼およびその製造方法
EP3978643A2 (fr) Acier inoxydable austénitique ayant une résistance améliorée et procédé de fabrication associé
RU2615667C1 (ru) Способ производства горячекатаных листов из низколегированной стали класса прочности к65 для электросварных прямошовных труб
JP4606113B2 (ja) 比例限界応力の高いオーステナイト系ステンレス鋼材および製造法
EP3699314A1 (fr) Acier inoxydable ferritique utilitaire possédant une excellente aptitude au façonnage à chaud et son procédé de fabrication
JP3858647B2 (ja) 低温継手靱性と耐ｓｓｃ性に優れた高張力鋼とその製造方法
KR102463485B1 (ko) 페라이트계 스테인리스 강판, 및 그 제조 방법 그리고 페라이트계 스테인리스 부재
JP4854924B2 (ja) プレス成形性に優れた高強度冷延鋼板およびその製造方法
KR20130046942A (ko) 고강도 열연강판 및 그 제조 방법

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: 20210210

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

A4 Supplementary search report drawn up and despatched

Effective date: 20210802

RIC1 Information provided on ipc code assigned before grant

Ipc: C22C 38/58 20060101AFI20210727BHEP

Ipc: C22C 38/42 20060101ALI20210727BHEP

Ipc: C22C 38/44 20060101ALI20210727BHEP

Ipc: C22C 38/02 20060101ALI20210727BHEP

Ipc: C22C 38/00 20060101ALI20210727BHEP

Ipc: C21D 1/26 20060101ALI20210727BHEP

Ipc: C22C 38/18 20060101ALI20210727BHEP

Ipc: C22C 38/20 20060101ALI20210727BHEP

Ipc: C22C 38/22 20060101ALI20210727BHEP

Ipc: C22C 38/32 20060101ALI20210727BHEP

Ipc: C22C 38/38 20060101ALI20210727BHEP

Ipc: C22C 38/40 20060101ALI20210727BHEP

Ipc: C22C 38/54 20060101ALI20210727BHEP

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
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

INTG Intention to grant announced

Effective date: 20220829

RAP3 Party data changed (applicant data changed or rights of an application transferred)

Owner name: POSCO HOLDINGS INC.

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

Ref country code: DE

Ref legal event code: R081

Ref document number: 602019024644

Country of ref document: DE

Owner name: POSCO CO., LTD, POHANG-SI, KR

Free format text: FORMER OWNER: POSCO HOLDINGS INC., SEOUL, KR

REG Reference to a national code

Ref country code: CH

Ref legal event code: PK

Free format text: BERICHTIGUNG B8

Ref country code: CH

Ref legal event code: EP

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: POSCO CO., LTD

REG Reference to a national code

Ref country code: AT

Ref legal event code: REF

Ref document number: 1544730

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230215

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602019024644

Country of ref document: DE

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20230118

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1544730

Country of ref document: AT

Kind code of ref document: T

Effective date: 20230118

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

Ref country code: NL

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: 20230118

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: 20230118

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: 20230518

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: 20230418

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: 20230118

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: 20230118

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: 20230118

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: 20230118

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: 20230118

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

Ref country code: SE

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

Effective date: 20230118

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: 20230118

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: 20230518

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: 20230419

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602019024644

Country of ref document: DE

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

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: 20230118

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: 20230118

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: 20230118

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: 20230118

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: 20230118

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

Ref country code: FI

Payment date: 20230816

Year of fee payment: 5

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

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: 20230118

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

Ref country code: FR

Payment date: 20230808

Year of fee payment: 5

Ref country code: DE

Payment date: 20230802

Year of fee payment: 5

26N No opposition filed

Effective date: 20231019

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

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: 20230118

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: 20230118

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

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

Ref country code: 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: 20230118

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: 20230808

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20230808

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: 20230808

Ref country code: CH

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

Effective date: 20230831

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20230831

REG Reference to a national code

Ref country code: IE

Ref legal event code: MM4A