EP2406405A1 - Acier austénitique résistant à la corrosion - Google Patents

Acier austénitique résistant à la corrosion

Info

Publication number
EP2406405A1
EP2406405A1 EP10714561A EP10714561A EP2406405A1 EP 2406405 A1 EP2406405 A1 EP 2406405A1 EP 10714561 A EP10714561 A EP 10714561A EP 10714561 A EP10714561 A EP 10714561A EP 2406405 A1 EP2406405 A1 EP 2406405A1
Authority
EP
European Patent Office
Prior art keywords
corrosion
resistant
austenitic steel
steel according
amount
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.)
Withdrawn
Application number
EP10714561A
Other languages
German (de)
English (en)
Inventor
Sebastian Weber
Lais MÚJICA RONCERY
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.)
Max Planck Institut fuer Eisenforschung
Original Assignee
Max Planck Institut fuer Eisenforschung
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 Max Planck Institut fuer Eisenforschung filed Critical Max Planck Institut fuer Eisenforschung
Publication of EP2406405A1 publication Critical patent/EP2406405A1/fr
Withdrawn legal-status Critical Current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
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing 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
    • 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
    • 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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • 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
    • C22C38/26—Ferrous alloys, e.g. steel alloys containing chromium with niobium or tantalum
    • 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
    • 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 invention relates to a corrosion-resistant austenitic steel, a process for its production and the use of this steel.
  • the strength of austenitic steels is particularly enhanced by the interstitially dissolved atoms of the elements carbon and nitrogen.
  • chromium and manganese are added in order to dissolve the volatile element nitrogen in the melt. While chromium alone promotes ferrite formation, an austenitic structure can be obtained with manganese by so-called solution annealing, which is stabilized by quenching to room temperature.
  • TWIP steel Twinning Induced Plasticity
  • An austenitic steel grade is the so-called TWIP steel (Twinning Induced Plasticity), in which an intensive twinning takes place during plastic deformation. This process usually takes place even at low load and solidifies the steel, the elongation at break is over 60%. These properties make the steel ideal for the production of sheet metal in the automotive industry, especially for accident-relevant areas of the body.
  • a TWIP steel usually has a carbon content of about 0.02 to 0.5 mass%, as alloying elements are manganese in amounts of 20 to 30% by mass, and in certain TWIP steels aluminum and silicon with up to to 3% by mass used.
  • EP 0 889 144 discloses a so-called TWIP steel, a lightweight steel, exhibiting a tensile strength up to 1100 MPa and from 1 to 6 mass% Si, 1 to 8 mass% Al, the total content of Al and Si is not greater than 12% by mass and contains 10 to 30% by mass of Mn.
  • the disclosed steels are characterized by higher yield stresses of 400 MPa and uniform expansion values of up to 70% and elongations at break up to 90%.
  • a disadvantage of the disclosed in this document steel is the low corrosion resistance.
  • a high-strength, austenitic stainless steel is characterized in that it is melted under normal atmospheric pressure of about 1 bar and in addition to iron 12 to 15% by mass of chromium, 17 to 21% by mass of manganese, ⁇ 0.7 mass. % Silicon, 0.4 to 0.7 mass% of carbon and nitrogen in total and ⁇ 1.0 mass% of other generation-related elements in total, wherein the ratio of carbon content and nitrogen content is between 0.6 and 1.0.
  • the disclosed steel shows no TWIP effect and can form martensite under severe deformation, which manifests itself among other things in a lower technical elongation.
  • WO2006 / 025412 discloses a corrosion-resistant TWIP steel containing Fe, Al, Si, Mn, Cr and Ni as main elements.
  • the obtained steel shows uniform elongation values above 50% and a tensile strength between 600 and 800 MPa.
  • the mechanical properties are comparable to those of the Fe, Al, Si and Mn-based steel disclosed in EP 0 889 144, but the addition of nickel increases the production cost and the lack of interstitial atoms results in lower strength.
  • Another austenitic steel containing C and N as alloying elements is disclosed in WO2006 / 027091, the steel described therein contains in addition to the alloying metals chromium and manganese in amounts of 16 to 21% by mass and 0.5 to 2.0 Mass% molybdenum and a total of 0.8 to 1, 1% by mass of carbon and nitrogen having a carbon / nitrogen ratio of 0.5 to 1, 1.
  • the disclosed steel exhibits mechanical strength, ductility, wear and corrosion resistance, and no ferromagnetism.
  • a disadvantage is that during the production of these alloys during solidification, a primary ferrite formation takes place, which can lead to leakage of nitrogen during melting and / or welding.
  • the present invention is a corrosion-resistant austenitic steel containing in addition to iron, each based on 100 mass percent,
  • the austenitic steel according to the invention exhibits TWIP (Twinning Induced Plasticity) properties and good corrosion resistance.
  • TWIP winning Induced Plasticity
  • An essential feature of this TWIP steel is a plasticity by formation of twin grain boundaries with a To obtain good corrosion resistance, that is, a steel that forms numerous twin grain boundaries in its microstructure upon deformation, thereby strongly and uniformly solidified, in the tensile test high technical strains and remains completely austenitic without formation of martensite.
  • the steel of the present invention has a stabilized austenitic structure formed by the combination of the main alloying elements Fe, Mn and Cr and the interstitial elements C and N.
  • the steel according to the invention shows an elongation at break of more than 90%, a yield strength of more than 400 MPa and a tensile strength of more than 900 MPa. Due to the combination of high elongation at break and yield strength, the steel according to the invention is extremely deformable.
  • the alloys according to the present invention show after targeted deformation no detectable by X-ray diffraction formation of ⁇ -martensite or e-martensite.
  • the alloy according to the invention in the abovementioned proportions of Cr, Mn, C and N, allows primary austenitic solidification, whereby a melt is obtained, from which nitrogen does not escape both during solidification and / or welding.
  • the alloy can thus be produced under normal pressure and also processed.
  • the alloy according to the invention shows a stable austenitic structure which prevents the formation of ferrite.
  • the alloy metal Cr and the existing N cause higher corrosion resistance compared to the prior art TWIP steels.
  • the individual proportions of the alloy metals Cr and Mn and of the additives N and C are set in such a ratio that the amount of Cr not only improves the solubility of N in the melt, but also has an advantageous effect on the corrosion resistance of the alloy without During the solidification of the melt primarily ferrite forms.
  • the formation of ferrite is disadvantageous because it would result in a lower solubility for nitrogen and thus a pore formation.
  • the weldability of the alloy according to the invention is also positively influenced. by avoiding nitrogen outgassing during solidification after fusion welding, and avoiding the formation of precipitates in the process - A - subsequent cooling of the solid material of the weld and the heat affected zone to room temperature. This is above all technologically important because after welding, the material cools relatively slowly and formation of precipitates at the weld and in the heat affected zone is undesirable.
  • the amount of Mn improves the ductility (plasticity, deformability).
  • the other ingredients C and N improve the mechanical properties and the corrosion resistance without forming nitrides and carbides.
  • the inventive ratio of C and N allows fully austenitic solidification without gases escape during melting or carbides or nitrides are formed during accelerated cooling.
  • the solubility for the desired amount of nitrogen in the melt is preferably given at 1500 0 C and 1 bar pressure.
  • the alloying metals Mn are present in an amount of from 22.0 to 30.0% by mass and chromium in an amount of from 11.0 to 13.0% by mass, in particular from 12.0 to 13.0% by mass. %, in front.
  • a total content of carbon and nitrogen between 0.5 and 0.8 mass% with a ratio of carbon to nitrogen of 0.5 to 0.8 has proven to be particularly favorable.
  • the alloys of this embodiment show advantageous material properties, so that they are suitable for use in lightweight constructions.
  • the alloy according to the invention contains secondary alloy metals with which the mechanical properties can be further changed.
  • the secondary alloying elements are preferably selected from Mo, Si, Nb, Hf, V, Zr, Ti, and Nd.
  • Mo is preferably contained in an amount of 1.0 to 2.0 mass%, Si in an amount of 0.1 to 2 mass%.
  • the metals Nb, Hf, V, Zr, Ti, and Nd may be contained in minor amounts and are also referred to as micro-alloying elements.
  • Nb may be present in an amount of 0.02 to 0.1% by weight, and the metals Hf, V, Zr, Ti and Nd each independently in amounts of 0 to 0.5% by weight.
  • Another object of the present invention is a method for producing a corrosion-resistant austenitic steel with TWIP properties in which the individual alloying metals melted under normal pressure and the diffusion annealing in a temperature range between 1000 and 1250 0 C over a period of 1 to 72 hours with following Quenching and hot / cold deformation is performed.
  • the melting process can be carried out at a pressure of 800-1,000 mbar in pure nitrogen or in an open furnace at ambient pressure, which corresponds to a nitrogen partial pressure of about ⁇ 00mbar.
  • Another object of the present invention relates to the use of the austenitic steel according to the invention for the production of structural components in constructions, in particular in the automotive industry.

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 Steel (AREA)
  • Heat Treatment Of Sheet Steel (AREA)

Abstract

L'invention concerne un acier austénitique résistant à la corrosion, caractérisé en ce qu'il comprend, rapporté respectivement à 100 pour cent en masse, 20 à 32% de manganèse, 10 à 15% de chrome, au total 0,5 à 1,3% de carbone et d'azote, le rapport de carbone à l'azote étant de 0,5 à 1,5, le reste étant constitué par du fer et par des impuretés résultant de la fusion. L'acier selon l'invention peut être fabriqué et traité sous une pression normale, et présente des propriétés TWIP. Il convient en particulier pour la production d'éléments de construction dans des constructions, par exemple dans l'industrie automobile.
EP10714561A 2009-03-10 2010-03-03 Acier austénitique résistant à la corrosion Withdrawn EP2406405A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102009003598A DE102009003598A1 (de) 2009-03-10 2009-03-10 Korrosionsbeständiger austenitischer Stahl
PCT/DE2010/000232 WO2010102601A1 (fr) 2009-03-10 2010-03-03 Acier austénitique résistant à la corrosion

Publications (1)

Publication Number Publication Date
EP2406405A1 true EP2406405A1 (fr) 2012-01-18

Family

ID=42313803

Family Applications (1)

Application Number Title Priority Date Filing Date
EP10714561A Withdrawn EP2406405A1 (fr) 2009-03-10 2010-03-03 Acier austénitique résistant à la corrosion

Country Status (7)

Country Link
US (1) US20120000580A1 (fr)
EP (1) EP2406405A1 (fr)
JP (1) JP5755153B2 (fr)
KR (1) KR20110136840A (fr)
CN (1) CN102365382A (fr)
DE (1) DE102009003598A1 (fr)
WO (1) WO2010102601A1 (fr)

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KR101353649B1 (ko) * 2011-12-23 2014-01-20 주식회사 포스코 내부식성이 우수한 스프링용 선재 및 강선, 스프링용 강선 및 스프링의 제조방법
ITRM20120647A1 (it) 2012-12-19 2014-06-20 Ct Sviluppo Materiali Spa ACCIAIO INOSSIDABILE AUSTENITICO AD ELEVATA PLASTICITÀ INDOTTA DA GEMINAZIONE, PROCEDIMENTO PER LA SUA PRODUZIONE, E SUO USO NELLÂeuro¿INDUSTRIA MECCANICA.
DE102013003516A1 (de) * 2013-03-04 2014-09-04 Outokumpu Nirosta Gmbh Verfahren zur Herstellung eines ultrahochfesten Werkstoffs mit hoher Dehnung
CN103667893B (zh) * 2013-12-06 2015-09-16 武汉钢铁(集团)公司 屈强比≤0.5的具有抗延迟断裂的高强钢及生产方法
PT2924131T (pt) * 2014-03-28 2019-10-30 Outokumpu Oy Aço inoxidável austenítico com elevado teor em manganês
CN104046909A (zh) * 2014-06-28 2014-09-17 张家港市华程异型钢管有限公司 一种奥氏体异型钢管
CN104046911A (zh) * 2014-06-30 2014-09-17 张家港华程机车精密制管有限公司 耐腐蚀性异形钢管
EP3095889A1 (fr) * 2015-05-22 2016-11-23 Outokumpu Oyj Procédé de fabrication d'un composant en acier austénitique
CN106399854B (zh) * 2016-06-23 2018-10-02 宝山钢铁股份有限公司 抗应力腐蚀开裂优良的高锰非磁性钢板及其制造方法
CN108642404B (zh) * 2018-07-05 2020-06-09 中国科学院合肥物质科学研究院 一种抗疲劳耐腐蚀孪生诱发塑性钢及其制备方法
US20230374636A1 (en) * 2020-10-22 2023-11-23 ExxonMobil Technology and Engineering Company High Manganese Alloyed Steels For Amine Service
WO2022087548A1 (fr) * 2020-10-22 2022-04-28 Exxonmobil Research And Engineering Company Aciers alliés à haute teneur en manganèse ayant une résistance à la fissuration améliorée
EP4316727A1 (fr) 2022-08-05 2024-02-07 Outokumpu Oyj Métal de remplissage pour le soudage de soudures différentes

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Also Published As

Publication number Publication date
WO2010102601A1 (fr) 2010-09-16
KR20110136840A (ko) 2011-12-21
US20120000580A1 (en) 2012-01-05
CN102365382A (zh) 2012-02-29
JP2012519780A (ja) 2012-08-30
JP5755153B2 (ja) 2015-07-29
DE102009003598A1 (de) 2010-09-16

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