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WO2025013665A1 - MATÉRIAU D'ALLIAGE Fe-Cr-Ni - Google Patents

MATÉRIAU D'ALLIAGE Fe-Cr-Ni Download PDF

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Publication number
WO2025013665A1
WO2025013665A1 PCT/JP2024/023678 JP2024023678W WO2025013665A1 WO 2025013665 A1 WO2025013665 A1 WO 2025013665A1 JP 2024023678 W JP2024023678 W JP 2024023678W WO 2025013665 A1 WO2025013665 A1 WO 2025013665A1
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alloy material
content
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alloy
yield strength
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Japanese (ja)
Inventor
誠也 岡田
桂一 近藤
一弥 中根
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Nippon Steel Corp
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Nippon Steel Corp
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • C22C30/02—Alloys containing less than 50% by weight of each constituent containing copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C30/00—Alloys containing less than 50% by weight of each constituent
    • C22C30/04—Alloys containing less than 50% by weight of each constituent containing tin or lead
    • 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
    • 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
    • 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
    • C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
    • 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
    • C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon

Definitions

  • This disclosure relates to alloy materials, and more specifically to Fe-Cr-Ni alloy materials.
  • Oil wells and gas wells use oil well alloy materials, such as oil well tubular goods.
  • Many oil wells are in sour environments that contain corrosive hydrogen sulfide.
  • a sour environment means an acidic environment that contains hydrogen sulfide.
  • a sour environment may contain not only hydrogen sulfide but also carbon dioxide. Materials used in such sour environments are required to have excellent corrosion resistance.
  • Materials that require excellent corrosion resistance include, for example, 18-8 stainless steel materials such as SUS304H, SUS316H, SUS321H, and SUS347H, and Fe-Cr-Ni alloy materials such as Alloy800H, which is specified as NCF800H in the JIS standard.
  • Fe-Cr-Ni alloy materials have superior corrosion resistance compared to 18-8 stainless steels.
  • Fe-Cr-Ni alloy materials are also more economical than Ni-based alloy materials such as Alloy617. For this reason, Fe-Cr-Ni alloy materials are sometimes used as alloy materials for oil wells used in sour environments.
  • Patent Document 1 JP Patent Publication No. 2-217445 (Patent Document 1) and WO 2015/072458 (Patent Document 2) propose an alloy material for oil wells that has excellent corrosion resistance.
  • Patent Document 1 The alloy material described in Patent Document 1 is an Fe-Cr-Ni alloy containing Ni: 27-32%, Cr: 24-28%, Cu: 1.25-3.0%, Mo: 1.0-3.0%, Si: 1.5-2.75%, Mn: 1.0-2.0%, N: 0.015% or less, B: 0.10% or less, C: 0.10% or less, Al: 0.30% or less, P: 0.03% or less, S: 0.02% or less, with the balance being essentially Fe and impurities.
  • Patent Document 1 describes this alloy material as having high strength, galling resistance, and corrosion resistance under stress.
  • the alloy material described in Patent Document 2 is a Ni-Cr alloy material and contains, in mass%, Si: 0.01 to 0.5%, Mn: 0.01 to less than 1.0%, Cu: 0.01 to less than 1.0%, Ni: 48 to less than 55%, Cr: 22 to 28%, Mo: 5.6 to less than 7.0%, N: 0.04 to 0.16%, sol.
  • the steel has a chemical composition consisting of Al: 0.03-0.20%, REM: 0.01-0.074%, W: 0-less than 8.0%, Co: 0-2.0%, one or more of Ca and Mg: 0.0003-0.01% in total, one or more of Ti, Nb, Zr, and V: 0-0.5% in total, with the balance being Fe and impurities, among the impurities being C: 0.03% or less, P: 0.03% or less, S: 0.001% or less, and O: 0.01% or less, and a dislocation density ⁇ satisfies the formula (7.0 ⁇ 10 ⁇ 15 ⁇ 2.7 ⁇ 10 ⁇ 16-2.67 ⁇ 10 ⁇ 17 ⁇ [REM(%)]).
  • Patent Document 2 describes that this alloy material has excellent hot workability and toughness, as well as excellent corrosion resistance (resistance to stress corrosion cracking at high temperatures exceeding 200°C and in environments containing hydrogen sulfide), and has a yield strength (0.2% yield strength) of 965 MPa or more.
  • inclined wells are also on the rise. Inclined wells are formed by drilling the well by bending the extension direction from vertical downward to horizontal. By including a portion that extends horizontally (horizontal well), inclined wells can cover a wide area of the strata in which production fluids such as crude oil and gas are buried, and the production efficiency of the production fluids can be improved.
  • the alloy material when used in such inclined wells, the alloy material may be subjected to compressive forces.
  • the alloy material has high not only tensile yield strength but also compressive yield strength.
  • Fe-Cr-Ni alloy materials intended for use in inclined wells not only have high strength but also have reduced strength anisotropy.
  • only the tensile yield strength is considered as the strength of the Fe-Cr-Ni alloy material.
  • the above Patent Documents 1 and 2 do not consider the strength anisotropy of the alloy material.
  • the objective of this disclosure is to provide an Fe-Cr-Ni alloy material that has high strength and reduced strength anisotropy.
  • the Fe-Cr-Ni alloy material according to the present disclosure has In mass percent, C: 0.030% or less, Si: 0.01-1.00%, Mn: 0.01 to 2.00%, P: 0.040% or less, S: 0.0050% or less, Al: 0.01-0.50%, Ni: 28.0-36.5%, Cr: 19.0-27.5%, Mo: 2.00-6.00%, Cu: 0.01-3.00%, N: 0.010 to less than 0.220%; Co: 0.01-2.00%, O: 0.010% or less, V: 0-0.50%, Nb: 0 to 0.10%, Ti: 0 to 0.40%, W: 0 to 3.0%, Sn: 0 to 0.010%, Ca: 0-0.0100%, B: 0 to 0.0100%, Mg: 0 to 0.0100%, Rare earth elements: 0 to 0.100%, and The balance is Fe and impurities, In the microstructure, the standard deviation of the grain size number of the austenite grains is 0.60 or less; The tens
  • the Fe-Cr-Ni alloy material disclosed herein has high strength and reduced strength anisotropy.
  • the inventors first focused on Fe-Cr-Ni alloy materials with a tensile yield strength of 110 ksi (758 MPa) or more as Fe-Cr-Ni alloy materials with high strength. Next, the inventors investigated the strength anisotropy of Fe-Cr-Ni alloy materials with a tensile yield strength of 758 MPa or more from the viewpoint of chemical composition.
  • the Fe-Cr-Ni alloy material having the above-mentioned chemical composition has a microstructure consisting of austenite.
  • microstructure consisting of austenite means that phases other than austenite are negligibly small. Therefore, the inventors have focused on the austenite grains of an Fe-Cr-Ni alloy material having the above-mentioned chemical composition and a tensile yield strength of 758 MPa or more, and have conducted detailed studies on methods for reducing the strength anisotropy of the alloy material.
  • Figure 1 is a diagram showing the relationship between the standard deviation ⁇ of the grain size number and the anisotropy index AI in this embodiment.
  • Figure 1 was created using the standard deviation ⁇ of the grain size number and the anisotropy index AI for an embodiment described later in which the configuration other than the standard deviation ⁇ of the grain size number satisfies the conditions of this embodiment.
  • the anisotropy index AI can be increased to 0.700 or more.
  • the standard deviation ⁇ of the grain size number exceeds 0.60, the anisotropy index AI drops to less than 0.700. Therefore, the Fe-Cr-Ni alloy material according to this embodiment satisfies the above-mentioned chemical composition, has a tensile yield strength of 758 MPa or more, and further, the standard deviation ⁇ of the grain size number is 0.60 or less.
  • the Fe-Cr-Ni alloy material according to this embodiment can reduce strength anisotropy.
  • the strength anisotropy of an alloy material can be reduced by setting the standard deviation ⁇ of the grain size number to 0.60 or less are not clear. However, it has been proven by the examples described below that the strength anisotropy can be reduced by satisfying the above-mentioned chemical composition, having a tensile yield strength of 758 MPa or more, and further setting the standard deviation ⁇ of the grain size number to 0.60 or less.
  • the Fe-Cr-Ni alloy material of this embodiment which was completed based on the above findings, has the following features:
  • the shape of the Fe-Cr-Ni alloy material according to this embodiment is not particularly limited.
  • the shape of the Fe-Cr-Ni alloy material according to this embodiment may be a plate, a rod with a circular cross section, or a tube. That is, the Fe-Cr-Ni alloy material according to this embodiment may be an alloy plate, a rod with a circular cross section, or an alloy pipe.
  • the alloy pipe may be a seamless alloy pipe or a welded alloy pipe. When the alloy material is an oil well alloy pipe, it is preferably a seamless alloy pipe.
  • the chemical composition of the Fe-Cr-Ni alloy material according to this embodiment contains the following elements.
  • Carbon (C) is an unavoidably contained impurity. That is, the lower limit of the C content is more than 0%. If the C content is too high, Cr carbides will be generated at the grain boundaries even if the contents of other elements are within the range of this embodiment. Cr carbides increase the cracking sensitivity at the grain boundaries. As a result, the corrosion resistance of the alloy material decreases. Therefore, the C content is 0.030% or less.
  • the preferred upper limit of the C content is 0.028%, more preferably 0.025%, more preferably 0.020%, and even more preferably 0.015%. It is preferable that the C content is as low as possible. However, an extreme reduction in the C content significantly increases the manufacturing cost. Therefore, when considering industrial production, the preferred lower limit of the C content is 0.001%, and even more preferably 0.003%.
  • Si 0.01 ⁇ 1.00% Silicon (Si) deoxidizes the alloy. If the Si content is too low, the above effect cannot be sufficiently obtained even if the contents of other elements are within the range of this embodiment. If the Si content is too high, the hot workability of the alloy material decreases even if the contents of other elements are within the ranges of this embodiment. Therefore, the Si content is 0.01 to 1.00%.
  • the lower limit of the Si content is preferably 0.05%, more preferably 0.10%, and even more preferably 0.20%.
  • the upper limit of the Si content is preferably 0.90%, and even more preferably is 0.80%, and more preferably 0.70%.
  • Mn 0.01-2.00% Manganese (Mn) deoxidizes and desulfurizes the alloy. If the Mn content is too low, the above effects cannot be sufficiently obtained even if the contents of other elements are within the ranges of this embodiment. If the Mn content is too high, the hot workability of the alloy material is reduced even if the contents of other elements are within the ranges of this embodiment. Therefore, the Mn content is set to 0.01 to 2.00%.
  • the lower limit of the Mn content is preferably 0.10%, more preferably 0.20%, and even more preferably 0.30%.
  • the upper limit of the Mn content is preferably 1.80%. , more preferably 1.60%, more preferably 1.50%, more preferably 1.30%, and even more preferably 1.00%.
  • Phosphorus (P) is an impurity that is inevitably contained. That is, the lower limit of the P content is more than 0%. P segregates at grain boundaries. Therefore, if the P content is too high, the hot workability and corrosion resistance of the alloy material will decrease even if the contents of other elements are within the range of this embodiment. Therefore, the P content is 0.040% or less.
  • the preferred upper limit of the P content is 0.035%, more preferably 0.030%, and even more preferably 0.025%.
  • the P content is preferably as low as possible. However, an extreme reduction in the P content significantly increases the manufacturing cost. Therefore, in consideration of industrial production, the preferred lower limit of the P content is 0.001%, more preferably 0.002%, and even more preferably 0.003%.
  • S 0.0050% or less Sulfur (S) is an impurity that is inevitably contained. That is, the lower limit of the S content is more than 0%. S segregates at grain boundaries. Therefore, if the S content is too high, the hot workability of the alloy material decreases even if the contents of other elements are within the range of this embodiment. Therefore, the S content is 0.0050% or less.
  • the preferred upper limit of the S content is 0.0040%, more preferably 0.0030%, and even more preferably 0.0020%.
  • the S content is preferably as low as possible. However, an extreme reduction in the S content significantly increases the manufacturing cost. Therefore, when considering industrial production, the preferred lower limit of the S content is 0.0001%, more preferably 0.0003%, and even more preferably 0.0005%.
  • Al 0.01 ⁇ 0.50%
  • Aluminum (Al) deoxidizes the alloy. It also forms oxides to fix oxygen and improve the hot workability of the alloy. It also improves the impact resistance and corrosion resistance of the alloy. If the Al content is too low, the above-mentioned effect cannot be sufficiently obtained even if the contents of the other elements are within the range of this embodiment. On the other hand, if the Al content is too high, the other element contents are not sufficiently obtained. Even if the amount is within the range of this embodiment, excessive Al oxides are generated, and the hot workability of the alloy material is rather deteriorated. Therefore, the Al content is set to 0.01 to 0.50%.
  • the lower limit of the Al content is preferably 0.02%, more preferably 0.03%, and even more preferably 0.05%.
  • the upper limit of the Al content is preferably 0.45%.
  • the Al content is more preferably 0.40%, and even more preferably 0.30%.
  • the Al content in this specification means the content of "acid-soluble Al", that is,
  • Nickel (Ni) is an austenite forming element and stabilizes austenite in the alloy material. If the Ni content is too low, the above effect is not sufficient even if the contents of other elements are within the range of this embodiment. On the other hand, Ni may increase the strength anisotropy. Therefore, if the Ni content is too high, the strength of the alloy material may not be obtained even if the contents of other elements are within the range of this embodiment. The anisotropy may increase. Therefore, the Ni content is 28.0 to 36.5%.
  • the lower limit of the Ni content is preferably 28.5%, more preferably 29.0%.
  • the upper limit of the Ni content is preferably 36.0%, more preferably 35.5%, and still more preferably 35.0%.
  • Chromium (Cr) enhances the corrosion resistance of the alloy material. Cr may also reduce the strength anisotropy of the alloy material. If the Cr content is too low, the contents of other elements may be within the range of this embodiment. On the other hand, if the Cr content is too high, the hot workability of the alloy material is deteriorated even if the contents of other elements are within the range of this embodiment. In this case, intermetallic compounds such as the ⁇ phase are more likely to form, and the corrosion resistance of the alloy material decreases. Therefore, the Cr content is 19.0 to 27.5%. Cr Content The preferred lower limit of the Cr content is 19.5%, more preferably 20.0%, further preferably 21.0%, and further preferably 22.0%. The preferred upper limit of the Cr content is 27. 0%, and more preferably 26.5%.
  • Mo Molybdenum
  • Mo contributes to the stabilization of the corrosion protective film and improves the corrosion resistance of the alloy material. Mo also increases the strength of the alloy material by solid solution strengthening. If the Mo content is too low, the alloy material containing other elements will have a high corrosion resistance. On the other hand, if the Mo content is too high, the alloy may not be able to obtain the above-mentioned effects even if the contents of the other elements are within the ranges of the present embodiment. The hot workability of the material is reduced. In this case, the manufacturing cost is also significantly increased. Therefore, the Mo content is 2.00 to 6.00%. The preferred lower limit of the Mo content is 2.20%. The upper limit of the Mo content is preferably 5.50%, more preferably 5.00%, and even more preferably 4.00%. .50%, and more preferably 4.00%.
  • Cu 0.01 ⁇ 3.00% Copper (Cu) contributes to stabilizing the corrosion protection film and enhances the corrosion resistance of the alloy material. If the Cu content is too low, the above effect will not be achieved even if the contents of other elements are within the range of this embodiment. On the other hand, if the Cu content is too high, the hot workability of the alloy material is reduced even if the contents of other elements are within the ranges of this embodiment.
  • the lower limit of the Cu content is preferably 0.02%, more preferably 0.05%, still more preferably 0.10%, and still more preferably 0.
  • the upper limit of the Cu content is preferably 2.80%, more preferably 2.50%, and even more preferably 2.00%.
  • N 0.010 to less than 0.220%
  • Nitrogen (N) enhances the strength of the alloy material by solid solution strengthening. If the N content is too low, the above effect cannot be sufficiently obtained even if the contents of other elements are within the range of this embodiment. On the other hand, if the N content is too high, the corrosion resistance of the alloy material may decrease even if the contents of other elements are within the range of this embodiment. Therefore, the N content is 0.010 to less than 0.220%.
  • the preferred lower limit of the N content is 0.015%, more preferably 0.020%, more preferably 0.030%, more preferably 0.050%, and more preferably 0.090%.
  • the preferred upper limit of the N content is 0.219%, more preferably 0.215%, more preferably 0.210%, and more preferably 0.200%.
  • Co Cobalt
  • the lower limit of the Co content is preferably 0.02%, more preferably 0.03%, further preferably 0.05%, and further preferably 0.10%.
  • the upper limit is 1.50%, more preferably 1.20%, further preferably 1.00%, and further preferably 0.90%.
  • Oxygen (O) is an impurity that is inevitably contained. That is, the lower limit of the O content is more than 0%. O forms oxides. Therefore, if the O content is too high, even if the contents of other elements are within the range of this embodiment, coarse oxides are formed in the alloy material, and the hot workability of the alloy material is reduced. In this case, the corrosion resistance of the alloy material is further reduced. Therefore, the O content is 0.010% or less.
  • the preferred upper limit of the O content is 0.008%, more preferably 0.005%.
  • the O content is preferably as low as possible. However, an extreme reduction in the O content significantly increases the manufacturing cost. Therefore, in consideration of industrial production, the preferred lower limit of the O content is 0.0001%, more preferably 0.001%, and even more preferably 0.002%.
  • the remainder of the chemical composition of the Fe-Cr-Ni alloy material according to this embodiment is composed of Fe and impurities.
  • impurities refer to substances that are mixed in from raw materials such as ore, scrap, or the manufacturing environment when the Fe-Cr-Ni alloy material is industrially manufactured, and are acceptable to the extent that they do not significantly adversely affect the effects of the Fe-Cr-Ni alloy material according to this embodiment.
  • the chemical composition of the Fe-Cr-Ni alloy material according to the present embodiment may further contain one or more elements selected from the group consisting of V, Nb, and Ti, all of which increase the strength of the alloy material.
  • V Vanadium
  • V is an optional element and may not be contained. In other words, the V content may be 0%. When contained, V forms carbonitrides with C and N, and increases the strength of the alloy material. If even a small amount of V is contained, the above effect can be obtained to some extent. However, if the V content is too high, even if the contents of other elements are within the range of this embodiment, excessive carbonitrides are formed, and the ductility of the alloy material decreases. Therefore, the V content is 0 to 0.50%.
  • the preferred lower limit of the V content is more than 0%, more preferably 0.01%, more preferably 0.03%, and even more preferably 0.05%.
  • the preferred upper limit of the V content is 0.40%, more preferably 0.30%, and even more preferably 0.20%.
  • Niobium (Nb) is an optional element and may not be contained. In other words, the Nb content may be 0%. When Nb is contained, it forms carbonitrides with C and N, and The strength of the alloy material is increased. Even if even a small amount of Nb is contained, the above effect can be obtained to a certain extent. However, if the Nb content is too high, even if the contents of other elements are within the range of this embodiment, Carbonitrides and the like are formed in excess, and the ductility of the alloy material is reduced. Therefore, the Nb content is 0 to 0.10%.
  • the lower limit of the Nb content is preferably more than 0%, and more preferably 0.
  • the upper limit of the Nb content is preferably 0.09%, more preferably 0.08%, and even more preferably 0.07%. More preferably, it is 0.06%, more preferably, it is 0.05%, more preferably, it is 0.04%, and more preferably, it is 0.03%.
  • Titanium (Ti) is an optional element and may not be contained. In other words, the Ti content may be 0%. When contained, Ti forms carbonitrides with C and N, and The strength of the alloy material is increased. Even if even a small amount of Ti is contained, the above effect can be obtained to a certain extent. However, if the Ti content is too high, even if the contents of other elements are within the range of this embodiment, Carbonitrides and the like are formed in excess, and the ductility of the alloy material is reduced. Therefore, the Ti content is 0 to 0.40%.
  • the lower limit of the Ti content is preferably more than 0%, and more preferably 0.
  • the upper limit of the Ti content is preferably 0.35%, more preferably 0.30%, and more preferably 0.01%, more preferably 0.03%, and even more preferably 0.05%.
  • the content is more preferably 0.20%, more preferably 0.15%, and even more preferably 0.10%.
  • the chemical composition of the Fe-Cr-Ni alloy material according to this embodiment may further contain one or more elements selected from the group consisting of W and Sn. All of these elements increase the corrosion resistance of the alloy material.
  • W 0 to 3.0%
  • Tungsten (W) is an optional element and may not be contained. That is, the W content may be 0%. When contained, W contributes to stabilization of the corrosion protection film and enhances the corrosion resistance of the alloy material. W further enhances the strength of the alloy material by solid solution strengthening. If even a small amount of W is contained, the above effect can be obtained to a certain extent. However, if the W content is too high, the hot workability of the alloy material decreases even if the contents of other elements are within the range of this embodiment. Therefore, the W content is 0 to 3.0%.
  • the preferred lower limit of the W content is more than 0%, more preferably 0.1%, more preferably 0.3%, and even more preferably 0.5%.
  • the preferred upper limit of the W content is 2.8%, more preferably 2.5%, more preferably 2.2%, and even more preferably 2.0%.
  • Tin (Sn) is an optional element and may not be contained. In other words, the Sn content may be 0%. When contained, Sn enhances the corrosion resistance of the alloy material. Even a small amount of Sn is contained. If the Sn content is too high, however, the hot workability of the alloy material is reduced even if the contents of other elements are within the ranges of this embodiment.
  • the Sn content is 0 to 0.010%.
  • the lower limit of the Sn content is preferably more than 0%, more preferably 0.001%, even more preferably 0.002%, and even more preferably
  • the upper limit of the Sn content is preferably 0.009%, more preferably 0.008%, and still more preferably 0.007%.
  • the chemical composition of the Fe-Cr-Ni alloy material according to this embodiment may further contain one or more elements selected from the group consisting of Ca, B, Mg, and rare earth elements (REM). All of these elements improve the hot workability of the alloy material.
  • Ca 0 ⁇ 0.0100%
  • Ca is an optional element and may not be contained. In other words, the Ca content may be 0%. When contained, Ca fixes S in the alloy as sulfides, The above effect can be obtained to some extent if even a small amount of Ca is contained. However, if the Ca content is too high, the contents of other elements will not fall within the range of this embodiment. Even if the Ca content is within the range, coarse oxides are formed in the alloy material, and the hot workability of the alloy material is rather deteriorated. Therefore, the Ca content is 0 to 0.0100%.
  • the lower limit is more than 0%, more preferably 0.0001%, even more preferably 0.0005%, even more preferably 0.0009%, even more preferably 0.0011%, and even more preferably is 0.0013%, and more preferably 0.0015%.
  • the upper limit of the Ca content is preferably 0.0080%, more preferably 0.0060%, and further preferably 0.0050%.
  • B 0-0.0100% Boron (B) is an optional element and may not be contained.
  • the B content may be 0%.
  • B fixes S in the alloy as sulfides, Even if even a small amount of B is contained, the above effects can be obtained to a certain extent. However, if the B content is too high, the contents of other elements will not fall within the range of this embodiment. Even if the B content is within the range, B segregates at grain boundaries, and the hot workability of the alloy material is rather deteriorated. Therefore, the B content is 0 to 0.0100%.
  • the preferable lower limit of the B content is 0. %, more preferably 0.0001%, more preferably 0.0003%, and even more preferably 0.0005%.
  • the upper limit of the B content is preferably 0.0080%, more preferably 0.0060%, still more preferably 0.0040%, still more preferably 0.0030%, and still more preferably 0.0020%. %, more preferably 0.0015%, and even more preferably 0.0010%.
  • Mg 0-0.0100%
  • Mg Magnesium (Mg) is an optional element and may not be contained. In other words, the Mg content may be 0%. When contained, Mg fixes S in the alloy as sulfides, Even if even a small amount of Mg is contained, the above effects can be obtained to some extent. However, if the Mg content is too high, the contents of other elements will be within the range of this embodiment. Even if the Mg content is within the range of 0.0100%, coarse oxides are formed in the alloy material, and the hot workability of the alloy material is rather deteriorated. Therefore, the Mg content is 0 to 0.0100%.
  • the lower limit is more than 0%, more preferably 0.0001%, more preferably 0.0003%, and even more preferably 0.0005%.
  • the preferred upper limit of the Mg content is 0.0080%. More preferably, it is 0.0060%, and even more preferably, it is 0.0040%.
  • Rare earth elements are optional elements and may not be included.
  • the REM content may be 0%.
  • REM fixes S in the alloy as sulfides. Even if even a small amount of REM is contained, the above effect can be obtained to some extent. However, if the REM content is too high, the contents of other elements may be different from those of the present embodiment. Even if the REM content is within the range, coarse oxides are formed in the alloy material, and the hot workability of the alloy material is rather deteriorated. Therefore, the REM content is 0 to 0.100%.
  • the lower limit is preferably more than 0%, more preferably 0.001%, more preferably 0.005%, and even more preferably 0.010%.
  • the upper limit of the REM content is preferably 0.080%. , more preferably 0.060%, and even more preferably 0.050%.
  • REM refers to one or more elements selected from the group consisting of scandium (Sc), atomic number 21; yttrium (Y), atomic number 39; and the lanthanides lanthanum (La), atomic number 57, to lutetium (Lu), atomic number 71.
  • the REM content in this specification refers to the total content of these elements.
  • the Fe-Cr-Ni alloy material according to the present embodiment has the above-mentioned chemical composition, and further has a standard deviation ⁇ of the grain size number of the austenite grains of 0.60 or less. As a result, the Fe-Cr-Ni alloy material according to the present embodiment can reduce strength anisotropy even if it has a tensile yield strength of 758 MPa or more.
  • the standard deviation ⁇ of the grain size number of the austenite grains is large, it is presumed that there are regions in the alloy material where coarse austenite grains (coarse grains) are unevenly distributed and regions where fine austenite grains (fine grains) are unevenly distributed.
  • the tensile yield strength of the Fe-Cr-Ni alloy material having the above-mentioned chemical composition is to be 758 MPa or more, in the manufacturing process described below, cold working or the like is performed after heat treatment such as solution treatment, and strain may be introduced into the alloy material. Therefore, anisotropy in strength may occur depending on the direction in which strain is introduced. Specifically, when cold drawing or cold rolling is performed as cold working, the tensile yield strength is greater than the compressive yield strength.
  • the inventors speculate that, based on the above mechanism, if the standard deviation ⁇ of the grain size number of the austenite grains of an Fe-Cr-Ni alloy material having the above chemical composition is 0.60 or less, the strength anisotropy can be reduced even if the material has a tensile yield strength of 758 MPa or more. It is possible that, based on a mechanism other than the above mechanism, if the standard deviation ⁇ of the grain size number of the austenite grains of an Fe-Cr-Ni alloy material having the above chemical composition is 0.60 or less, the strength anisotropy can be reduced even if the material has a tensile yield strength of 758 MPa or more.
  • the preferred upper limit of the standard deviation ⁇ of the grain size number of the austenite grains is 0.58, more preferably 0.55, and even more preferably 0.53.
  • the smaller the standard deviation ⁇ of the grain size number of the austenite grains the more preferable.
  • the lower limit of the standard deviation ⁇ of the grain size number of the austenite grains may be 0.00, 0.05, 0.10, or 0.15.
  • the standard deviation ⁇ of the grain size number of the austenite grains can be found by the following method. Specifically, a test piece for microstructure observation is prepared from the Fe-Cr-Ni alloy material according to this embodiment. If the alloy material is in the form of a plate, the test piece is prepared from the center of the plate thickness. If the alloy material is in the form of a tube, the test piece is prepared from the center of the wall thickness. If the alloy material is in the form of a rod with a circular cross section, the test piece is prepared from the R/2 position. In this specification, the R/2 position means the center position of the radius R in a cross section perpendicular to the axial direction. The size of the test piece is not particularly limited as long as it can provide the observation surface described below.
  • the observation surface of the prepared test piece is polished to a mirror finish, it is etched using aqua regia (a solution of hydrochloric acid and nitric acid mixed in a ratio of 3:1) to reveal the austenite grain boundaries.
  • aqua regia a solution of hydrochloric acid and nitric acid mixed in a ratio of 3:1
  • 10 fields of view are selected at random and observed using an optical microscope to generate photographic images.
  • the magnification for microscopic observation can be set appropriately depending on the grain size. Specifically, in microscopic observation, the magnification is set so that the field of view contains, for example, 50 or more grains.
  • the grain size number of the austenite grains is not particularly limited as long as the standard deviation ⁇ is 0.60 or less.
  • the lower limit of the grain size number of the austenite grains may be, for example, 4.0, 4.5, or 5.0.
  • the upper limit of the grain size number of the austenite grains may be, for example, 12.0, 11.5, or 11.0.
  • the grain size number of the austenite grains means the arithmetic average value of the 10 grain size numbers obtained by the above-mentioned method.
  • the Fe-Cr-Ni alloy material according to the present embodiment has the above-mentioned chemical composition, and further has a standard deviation ⁇ of the grain size number of the austenite grains of 0.60 or less. As a result, the Fe-Cr-Ni alloy material according to the present embodiment has a tensile yield strength of 758 MPa or more, but has reduced strength anisotropy.
  • the alloy material according to this embodiment can suppress the manifestation of strength anisotropy due to variations in grain size, because the standard deviation ⁇ of the grain size number of the austenite grains is 0.60 or less. Therefore, the alloy material according to this embodiment can reduce strength anisotropy even if it has a high tensile yield strength of 758 MPa or more.
  • the preferred lower limit of the tensile yield strength is 800 MPa, more preferably 830 MPa, and even more preferably 860 MPa.
  • the upper limit of the tensile yield strength is not particularly limited, and may be, for example, 1240 MPa, 1200 MPa, or 1150 MPa.
  • the compressive yield strength is not particularly limited.
  • the lower limit of the compressive yield strength may be, for example, 600 MPa, 610 MPa, or 630 MPa.
  • the upper limit of the compressive yield strength may be, for example, less than 1240 MPa, less than 1200 MPa, or less than 1150 MPa.
  • the method of measuring the tensile yield strength and compressive yield strength in this embodiment will be described later.
  • the Fe-Cr-Ni alloy material according to the present embodiment has the above-mentioned chemical composition, and further has a standard deviation ⁇ of the grain size number of the austenite grains of 0.60 or less. As a result, the Fe-Cr-Ni alloy material according to the present embodiment has a reduced strength anisotropy even though it has a tensile yield strength of 758 MPa or more.
  • the reduced strength anisotropy means that the anisotropy index AI is 0.700 or more.
  • the anisotropy index AI means the ratio (compressive YS/tensile YS) of the compressive yield strength (compressive YS) to the tensile yield strength (tensile YS).
  • the preferred lower limit of the anisotropy index AI is 0.710, more preferably 0.730, and even more preferably 0.750.
  • the upper limit of the anisotropy index AI is substantially less than 1.000, more preferably 0.999, more preferably 0.990, and even more preferably 0.980.
  • the anisotropy index AI, tensile yield strength, and compressive yield strength of the Fe-Cr-Ni alloy material according to this embodiment can be determined by the following method. First, the tensile yield strength and compressive yield strength of the Fe-Cr-Ni alloy material according to this embodiment are determined.
  • the tensile yield strength of the Fe-Cr-Ni alloy material according to this embodiment can be determined by the following method.
  • a tensile test is performed according to the method of ASTM E8/E8M (2021).
  • a round bar test piece is prepared from the alloy material according to this embodiment.
  • the alloy material has a plate shape
  • a round bar test piece is prepared from the center of the plate thickness.
  • the alloy material has a tubular shape
  • a round bar test piece is prepared from the center of the wall thickness.
  • a round bar test piece is prepared from the R/2 position.
  • the size of the round bar test piece is, for example, a parallel part diameter of 4 mm and a gauge length of 20 mm.
  • the axial direction of the round bar test piece is parallel to the rolling direction of the alloy material.
  • a tensile test is performed using the round bar test piece at room temperature (25°C) in the air, and the obtained 0.2% offset yield strength is defined as the tensile yield strength (MPa).
  • the tensile yield strength (MPa) is calculated by rounding the obtained value to the nearest tenth.
  • the compressive yield strength of the Fe-Cr-Ni alloy material according to this embodiment can be determined by the following method.
  • a compression test is performed according to ASTM E9 (2019).
  • a cylindrical test piece is prepared from the alloy material according to this embodiment. If the alloy material is plate-shaped, a cylindrical test piece is prepared from the center of the plate thickness. If the alloy material is tubular, a cylindrical test piece is prepared from the center of the wall thickness. If the alloy material is rod-shaped with a circular cross section, a cylindrical test piece is prepared from the R/2 position.
  • the size of the cylindrical test piece is, for example, 4 mm in parallel diameter and 8 mm in length.
  • the axial direction of the cylindrical test piece is parallel to the rolling direction of the alloy material.
  • a compression test is performed using the cylindrical test piece at room temperature (25°C) in the air, and the obtained 0.2% offset yield strength is defined as the compressive yield strength (MPa).
  • the compressive yield strength (MPa) is determined by rounding off the obtained value to the nearest tenth.
  • the anisotropy index AI is calculated by rounding the obtained value to the fourth decimal place.
  • the method for producing a seamless alloy pipe includes a step of preparing a material (material preparation step), a step of producing a mother pipe from the material (hot working step), a step of cold working the produced mother pipe (first cold working step), a step of performing a solution treatment (solution treatment step), and a step of cold working the solution-treated mother pipe (second cold working step). Note that the method for producing an Fe—Cr—Ni alloy material according to this embodiment is not limited to the production method described below.
  • an Fe—Cr—Ni alloy having the above-mentioned chemical composition is melted.
  • the Fe—Cr—Ni alloy may be melted in an electric furnace, or in an Ar—O 2 mixed gas bottom blown decarburization furnace (AOD furnace). It may also be melted in a vacuum decarburization furnace (VOD furnace).
  • the melted Fe—Cr—Ni alloy may be made into an ingot by an ingot casting method, or into a slab, bloom, or billet by a continuous casting method. If necessary, the slab, bloom, or ingot may be rolled to produce a billet.
  • the material (slab, bloom, or billet) is produced by the above-mentioned process.
  • the prepared material is hot worked to produce an intermediate alloy material (blank pipe).
  • the method of hot working is not particularly limited and may be a well-known method. That is, in this embodiment, the hot working may be hot rolling, hot extrusion, or hot forging. In the hot working, the heating temperature of the material is, for example, 1100 to 1300°C.
  • a round billet is pierced and rolled using a piercing machine.
  • the piercing ratio is not particularly limited and is, for example, 1.0 to 4.0.
  • the blank pipe that has been pierced and rolled may also be hot rolled using a mandrel mill, reducer, sizing mill, etc. to produce a blank pipe.
  • the intermediate alloy material refers to a plate-shaped alloy material when the final product is an alloy plate, a blank tube when the final product is an alloy pipe, and an alloy material with a circular cross section perpendicular to the axial direction when the final product is a solid material with a circular cross section.
  • the alloy material is a solid material with a circular cross section
  • the material is first heated in a heating furnace.
  • the heating temperature is not particularly limited, but is, for example, 1100 to 1300°C.
  • the material extracted from the heating furnace is subjected to hot processing to produce an intermediate alloy material with a circular cross section perpendicular to the axial direction.
  • the hot processing is, for example, blooming rolling by a blooming mill, or hot rolling by a continuous rolling mill.
  • the continuous rolling mill has a horizontal stand having a pair of grooved rolls arranged side by side in the vertical direction, and a vertical stand having a pair of grooved rolls arranged side by side in the horizontal direction, alternately arranged.
  • the alloy material is an alloy plate
  • the material is first heated in a heating furnace.
  • the heating temperature is not particularly limited, but is, for example, 1100 to 1300°C.
  • the material extracted from the heating furnace is hot rolled using a blooming mill and a continuous rolling mill to produce intermediate alloy material in the form of alloy plates.
  • the produced intermediate alloy material (blank pipe) is subjected to cold working.
  • the cold working may be cold drawing, or cold rolling.
  • a continuous rolling mill equipped with a plurality of cold rolling stands may be used. That is, in the first cold working step according to the present embodiment, a known cold rolling mill may be used.
  • the cold working may be performed under known conditions. Specifically, the temperature of the intermediate alloy material (base pipe) during cold working may be, for example, room temperature to 300°C.
  • a preferred cold working ratio R1 (%) is 5% or more.
  • the cold working ratio R1 means the reduction rate of the cross-sectional area of the intermediate alloy material (blank tube) from before the start of the first cold working step to after the end of the first cold working step.
  • the cold working ratio R1 (%) of the first cold working step is defined by the following formula (A).
  • R1 (%) 100 (1-S1(1)/S0(1)) (A)
  • the cold working rate R1 in the first cold working process is 5% or more.
  • the upper limit of the cold working rate R1 in the first cold working process is not particularly limited, but is, for example, 30%.
  • solution treatment process a solution treatment is performed on the intermediate alloy material (blank pipe) that has been subjected to cold working.
  • the method of the solution treatment is not particularly limited and may be a well-known method.
  • the blank pipe is loaded into a heat treatment furnace, held at a desired temperature, and then quenched.
  • the temperature at which the solution treatment is performed means the temperature (°C) of the heat treatment furnace for performing the solution treatment.
  • the time for which the solution treatment is performed means the time for which the blank pipe is held at the solution temperature.
  • the residence time at 900 to 1050°C is 9 minutes or more.
  • the intermediate alloy material having the above-mentioned chemical composition recrystallization and grain growth are likely to proceed at 900°C or higher. Therefore, if the residence time at 900 to 1050°C is too short, temperature variations in the intermediate alloy material are likely to occur, and recrystallization and grain growth are likely to become non-uniform.
  • the residence time at 900 to 1050°C is 9 minutes or more, recrystallization and grain growth are likely to become uniform. In this case, recrystallization is further likely to be promoted in the heat treatment at 1060°C or higher. As a result, the standard deviation ⁇ of the grain size number of the manufactured Fe-Cr-Ni alloy material can be stably reduced.
  • the residence time at 900 to 1050°C during heating in the solution treatment process is preferably 9 minutes or more.
  • a more preferable lower limit for the residence time at 900 to 1050°C during heating in the solution treatment process is 10 minutes.
  • the upper limit for the residence time at 900 to 1050°C during heating in the solution treatment process is, for example, 60 minutes.
  • the upper limit for the residence time at 900 to 1050°C during heating in the solution treatment process may be 45 minutes or 30 minutes.
  • the solution temperature in the solution treatment step according to this embodiment is 1060 to 1300°C. If the solution temperature is too low, precipitates (such as the ⁇ phase, which is an intermetallic compound) may remain in the blank tube after solution treatment. In this case, the corrosion resistance of the manufactured Fe-Cr-Ni alloy material may decrease. On the other hand, if the solution temperature is too high, the effect of the solution treatment is saturated. Therefore, in this embodiment, it is preferable to set the solution temperature in the solution treatment step to 1060 to 1300°C.
  • the holding time is, for example, 5 to 180 minutes.
  • the rapid cooling method is, for example, water cooling.
  • the solution-treated intermediate alloy material (blank tube) is cold worked to produce an Fe—Cr—Ni alloy material.
  • the cold working is In other words, in the second cold working step according to the present embodiment, the known cold working is performed in the same manner as in the first cold working step.
  • the temperature of the intermediate alloy material (base pipe) during cold working may be, for example, room temperature to 300°C.
  • a preferred cold working ratio R2 is 5 to 50%.
  • the cold working ratio R2 means a reduction ratio of a cross-sectional area of an intermediate alloy material (blank tube) from before the start of the second cold working step to after the end of the second cold working step.
  • the cold working rate R2 is 5 to 50%, the tensile yield strength of the Fe-Cr-Ni alloy material after the second cold working process can be stably set to 758 MPa or more. Therefore, it is preferable that the cold working rate R2 is 5 to 50%.
  • the cold working rate R1 (%) of the first cold working step and the cold working rate R2 (%) of the second cold working step satisfy the above-mentioned range, and the total cold working rate in the manufacturing process is not particularly limited.
  • the above manufacturing method allows the production of the Fe-Cr-Ni alloy material according to this embodiment.
  • the method for producing seamless alloy pipes has been described as one example.
  • the Fe-Cr-Ni alloy material according to this embodiment may be in other shapes, such as a plate shape.
  • a manufacturing method for other shapes, such as a plate shape also includes, for example, a material preparation step, a hot working step, a solution treatment step, and a cold working step.
  • the above manufacturing method is one example, and the material may be produced by other manufacturing methods. The present invention will be described in more detail below with reference to examples.
  • Alloys having the chemical compositions shown in Tables 1A and 1B were produced by high-frequency vacuum melting.
  • "-" means that the content of each element is at the impurity level.
  • the W content of A is rounded off to one decimal place and is 0%.
  • the V content, Nb content, and Ti content of A are rounded off to one decimal place and are 0%.
  • the Sn content and REM content of A are rounded off to the fourth decimal place and are 0%.
  • the Ca content, B content, and Mg content of A are rounded off to the fifth decimal place and are 0%.
  • a solution treatment was carried out on the alloy plates of each test number that had been subjected to the first cold working.
  • the alloy plates that had been subjected to the first cold working were heated and held at the solution temperature (°C) shown in Table 2 for the holding time (min) shown in Table 2, and then water-cooled.
  • the holding time at 900-1050°C when heating to the solution temperature is shown in the "Holding time (min)" column in Table 2.
  • a second cold working process was carried out on the alloy plates of each test number that had been subjected to solution treatment.
  • the cold working ratio R2 (%) of the second cold working process carried out on the alloy plates of each test number is shown in Table 2. Note that for test numbers 1, 7 and 15, cold drawing was carried out as the cold working process. For each test number except test numbers 1, 7 and 15, cold rolling was carried out as the cold working process.
  • the total cold working ratio R (%) of the cold working performed on the alloy plate of each test number is shown in Table 2.
  • the total cold working ratio R (%) is defined by the following formula (C).
  • R (%) R1 (%) + R2 (%) (C)
  • the cold working rate (%) of the first cold working is substituted for R1 in the formula (C)
  • the cold working rate (%) of the second cold working is substituted for R2.
  • a strength anisotropy measurement test was carried out on the alloy plate of each test number to obtain the anisotropy index AI.
  • the tensile yield strength (MPa) and the compressive yield strength (MPa) were first obtained by the above-mentioned method.
  • a round bar test piece for a tensile test and a cylindrical test piece for a compression test were prepared from the center of the plate thickness of the alloy plate of each test number.
  • the round bar test piece had a parallel part diameter of 4 mm and a gauge length of 20 mm.
  • the cylindrical test piece had a parallel part diameter of 4 mm and a length of 8 mm.
  • the axial direction of the round bar test piece and the cylindrical test piece was parallel to the rolling direction of the alloy plate.
  • a tensile test was performed on the round bar test pieces at room temperature (25°C) in air in accordance with ASTM E8/E8M (2021).
  • the 0.2% offset yield strength obtained by the tensile test was defined as the tensile yield strength (MPa).
  • a compression test was performed on the cylindrical test pieces at room temperature (25°C) in air in accordance with ASTM E9 (2019).
  • the 0.2% offset yield strength obtained by the compression test was defined as the compressive yield strength (MPa).
  • the ratio of the compressive yield strength (compressive YS) to the obtained tensile yield strength (tensile YS) was calculated and defined as the anisotropy index AI.
  • the obtained tensile yield strength is shown in the "Tensile YS (MPa)” column of Table 3
  • the compressive yield strength is shown in the “Compressive YS (MPa)” column of Table 3
  • the anisotropy index AI is shown in the "Anisotropy Index AI” column of Table 3.
  • the Ni content of the alloy plates of test numbers 27 and 28 was too high.
  • the tensile yield strength of these alloy plates was 758 MPa or more, the anisotropy index AI was less than 0.700, and the strength anisotropy was not reduced.
  • the alloy plates of test numbers 29 and 30 had too low a Cr content. As a result, although the alloy plates had a tensile yield strength of 758 MPa or more, the anisotropy index AI was less than 0.700, and the strength anisotropy was not reduced.
  • the alloy plates of test numbers 31 to 33 had too low a cold working ratio R1 in the first cold working process. As a result, the standard deviation ⁇ of the grain size number of these alloy plates exceeded 0.60. As a result, although these alloy plates had a tensile yield strength of 758 MPa or more, the anisotropy index AI was less than 0.700, and the strength anisotropy was not reduced.
  • the alloy plates of test numbers 34 to 36 had too short a residence time at 900 to 1050°C during heating in the solution treatment process. As a result, the standard deviation ⁇ of the grain size number of these alloy plates exceeded 0.60. As a result, although these alloy plates had a tensile yield strength of 758 MPa or more, the anisotropy index AI was less than 0.700, and the strength anisotropy was not reduced.

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Abstract

La présente invention concerne un matériau d'alliage Fe-Cr-Ni qui présente une résistance élevée et une anisotropie de résistance réduite. Un matériau d'alliage Fe-Cr-Ni selon la présente invention contient, en % en masse, au plus 0,030 % de C, 0,01 à 1,00 % de Si, 0,01 à 2,00 % de Mn, au plus 0,040 % de P, au plus 0,0050 % de S, 0,01 à 0,50% d'Al, 28,0 à 36,5 % de Ni, 19,0 à 27,5 % de Cr, 2,00 à 6,00 % de Mo, 0,01 à 3,00 % de Cu, pas moins de 0,010 % mais moins de 0,220 % de N, 0,01 à 2,00 % de Co et au plus 0,010 % de O, le reste étant constitué de Fe et d'impuretés. Dans la microstructure, l'écart-type du nombre de tailles de grain cristallin des grains d'austénite est au plus de 0,60, et la limite d'élasticité en traction est au moins de 758 MPa.
PCT/JP2024/023678 2023-07-07 2024-06-28 MATÉRIAU D'ALLIAGE Fe-Cr-Ni Pending WO2025013665A1 (fr)

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Citations (7)

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Publication number Priority date Publication date Assignee Title
CN101613833A (zh) * 2008-06-25 2009-12-30 宝山钢铁股份有限公司 高酸性深井用Ni基合金油套管及制造方法
WO2012128258A1 (fr) * 2011-03-24 2012-09-27 住友金属工業株式会社 Conduite en alliage de système austénitique et son procédé de fabrication
CN102899578A (zh) * 2011-07-25 2013-01-30 宝山钢铁股份有限公司 一种铁镍铬合金油套管及制造方法
WO2018225831A1 (fr) * 2017-06-08 2018-12-13 新日鐵住金株式会社 Tuyau d'alliage à base de ni, de qualité nucléaire
WO2018225869A1 (fr) * 2017-06-09 2018-12-13 新日鐵住金株式会社 Tuyau en alliage austénitique et son procédé de production
WO2021256128A1 (fr) * 2020-06-19 2021-12-23 Ｊｆｅスチール株式会社 Tuyau en alliage et son procédé de fabrication
WO2023132339A1 (fr) * 2022-01-06 2023-07-13 日本製鉄株式会社 MATÉRIAU D'ALLIAGE Fe-Cr-Ni

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101613833A (zh) * 2008-06-25 2009-12-30 宝山钢铁股份有限公司 高酸性深井用Ni基合金油套管及制造方法
WO2012128258A1 (fr) * 2011-03-24 2012-09-27 住友金属工業株式会社 Conduite en alliage de système austénitique et son procédé de fabrication
CN102899578A (zh) * 2011-07-25 2013-01-30 宝山钢铁股份有限公司 一种铁镍铬合金油套管及制造方法
WO2018225831A1 (fr) * 2017-06-08 2018-12-13 新日鐵住金株式会社 Tuyau d'alliage à base de ni, de qualité nucléaire
WO2018225869A1 (fr) * 2017-06-09 2018-12-13 新日鐵住金株式会社 Tuyau en alliage austénitique et son procédé de production
WO2021256128A1 (fr) * 2020-06-19 2021-12-23 Ｊｆｅスチール株式会社 Tuyau en alliage et son procédé de fabrication
WO2023132339A1 (fr) * 2022-01-06 2023-07-13 日本製鉄株式会社 MATÉRIAU D'ALLIAGE Fe-Cr-Ni

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