WO2015129403A1 - 高強度ばね用圧延材および高強度ばね用ワイヤ - Google Patents

高強度ばね用圧延材および高強度ばね用ワイヤ Download PDF

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WO2015129403A1
WO2015129403A1 PCT/JP2015/052960 JP2015052960W WO2015129403A1 WO 2015129403 A1 WO2015129403 A1 WO 2015129403A1 JP 2015052960 W JP2015052960 W JP 2015052960W WO 2015129403 A1 WO2015129403 A1 WO 2015129403A1
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amount
wire
rolled material
steel
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PCT/JP2015/052960
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French (fr)
Japanese (ja)
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敦彦 竹田
智一 増田
将 高山
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株式会社神戸製鋼所
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Application filed by 株式会社神戸製鋼所 filed Critical 株式会社神戸製鋼所
Priority to KR1020187028885A priority Critical patent/KR20180112882A/ko
Priority to MX2016011156A priority patent/MX2016011156A/es
Priority to CN201580010254.4A priority patent/CN106062229B/zh
Priority to EP15755898.2A priority patent/EP3112491A4/en
Priority to US15/120,168 priority patent/US20170058376A1/en
Priority to KR1020167024864A priority patent/KR20160119216A/ko
Publication of WO2015129403A1 publication Critical patent/WO2015129403A1/ja

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    • 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
    • C21D9/02—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for springs
    • 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
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/525—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length for wire, for rods
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    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires
    • C21D8/065—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires of ferrous alloys
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    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
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    • C—CHEMISTRY; METALLURGY
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    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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    • 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
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    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/34—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of silicon
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    • 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
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    • 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
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    • 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
    • C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel 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
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—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
    • C21D2211/004—Dispersions; Precipitations
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/008—Martensite
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
    • C21D3/02—Extraction of non-metals
    • C21D3/06—Extraction of hydrogen
    • 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
    • C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires

Definitions

  • the present invention relates to a high-strength spring rolled material and a high-strength spring wire using the same. Specifically, it is a rolled material and a high-strength spring wire useful as a raw material for a high-strength spring used in a tempered state, that is, quenched and tempered.
  • the present invention relates to a high-strength spring wire having excellent corrosion fatigue characteristics even when the tensile strength after processing is as high as 1900 MPa or higher.
  • Coil springs used in automobiles for example, valve springs and suspension springs used in engines and suspensions, are required to be light in weight to reduce exhaust gas and improve fuel efficiency, and require high strength. . Higher strength springs have poor toughness, tend to cause hydrogen embrittlement, and deteriorate corrosion fatigue characteristics. Therefore, a steel wire for high-strength springs used for manufacturing a spring (hereinafter, the steel wire may be referred to as a wire) is required to have excellent corrosion fatigue characteristics. Corrosion fatigue failure occurs when hydrogen generated by corrosion penetrates into the steel and causes embrittlement of the steel due to the hydrogen. To improve the corrosion fatigue properties, improve the corrosion resistance and hydrogen embrittlement resistance of the steel. It is necessary.
  • Controlling the chemical composition is known as a method for enhancing the corrosion fatigue characteristics of high-strength spring wires.
  • these methods use a large amount of alloy elements, which is not always desirable from the viewpoint of increasing manufacturing costs and saving resources.
  • the steel wire is heated to a quenching temperature and hot-formed into a spring shape, and then oil-cooled and tempered, and the steel wire is quenched and tempered and then cold-formed into a spring shape.
  • the method is known.
  • quenching and tempering before forming is performed by high-frequency heating.
  • Patent Document 1 discloses a structure in which a wire is cold drawn and then quenched and tempered by high-frequency induction heating. A technique for adjusting the above is disclosed.
  • the structure fraction of pearlite is 30% or less
  • the structure fraction composed of martensite and bainite is 70% or more
  • cold drawing is performed at a predetermined area reduction rate, followed by quenching and tempering. Undissolved carbides are reduced and delayed fracture characteristics are improved.
  • Patent Document 2 a rolled wire is drawn in an example and subjected to quenching and tempering treatment by induction heating. This technology focuses on achieving both high strength and moldability such as coiling properties, and does not take into account any corrosion fatigue properties.
  • Patent Document 3 focuses on the amount of hydrogen in steel evaluated by the total amount of hydrogen released when the temperature is raised from room temperature to 350 ° C., and is hot rolled with excellent wire drawing workability under strong wire drawing conditions. Proposes wire rods. However, Patent Document 3 pays attention only to the wire drawing property in a special process called strong wire drawing, and does not consider any corrosion fatigue characteristics after quenching and tempering which are most important in a suspension spring or the like.
  • the present invention has been made in view of the above circumstances, and its purpose is a material for hot-winding and cold-winding high-strength springs, which is quenched even if the amount of alloying elements is suppressed.
  • An object of the present invention is to provide a rolled material that can exhibit excellent corrosion fatigue characteristics after tempering, and a high-strength spring wire obtained from such a rolled material.
  • the rolled material for high-strength springs of the present invention that has solved the above problems is % By mass C: 0.39 to 0.65%, Si: 1.5 to 2.5%, Mn: 0.15 to 1.2%, P: more than 0%, 0.015% or less, S: more than 0%, 0.015% or less, Al: 0.001 to 0.1%, Cu: 0.10 to 0.80%, Ni: 0.10-0.80% and O: more than 0%, 0.0010% or less, respectively, the balance being iron and inevitable impurities,
  • the number of oxide inclusions having an average diameter of 25 ⁇ m or more is 30 or less per 100 g of steel material, and the amount of non-diffusible hydrogen is 0.40 mass ppm or less.
  • the rolled material for high-strength springs of the present invention preferably further contains one or more kinds belonging to any of the following (a) to (d) in mass%.
  • the present invention also includes a high-strength spring wire made of any of the chemical components of steel described above, having an area ratio of tempered martensite of 80% or more and a tensile strength of 1900 MPa or more.
  • the oxide inclusions in the rolled material are reduced and the amount of non-diffusible hydrogen is suppressed, so excellent corrosion even after quenching and tempering. Exhibits fatigue properties.
  • the corrosion fatigue characteristics of the wire can be improved even if the steel material cost is reduced, so that a high strength spring that is extremely unlikely to cause corrosion fatigue failure, for example, a coil such as a suspension spring that is one of automotive parts The spring can be supplied at low cost.
  • FIG. 1 is a graph showing the influence of the number of inclusions in the rolled material and the amount of non-diffusible hydrogen on the corrosion fatigue characteristics.
  • the present inventors examined the factors affecting the hydrogen embrittlement resistance and the corrosion resistance from various angles. As a result, corrosion and fatigue properties can be achieved by quenching and tempering a rolled material in which both the number of oxide inclusions of a given size in steel and the amount of non-diffusible hydrogen in the steel are controlled appropriately. It became clear that improved significantly. When there are many large oxide inclusions in the steel, not only the atmospheric durability is lowered, but also a “strain field” is formed around the steel, and it becomes a hydrogen accumulation point, which makes the surrounding grain boundary particularly brittle. It has been found that the corrosion fatigue characteristics are lowered.
  • the corrosion fatigue characteristics can be improved even if the addition amount of the corrosion resistance improving element is reduced.
  • the requirements for the number of oxide inclusions, the amount of non-diffusible hydrogen in steel, and the chemical composition specified in the present invention will be described below.
  • the number of oxide inclusions When large oxide inclusions are present in the steel, not only the atmospheric durability is lowered, but also a strain field is formed around the inclusions, forming hydrogen accumulation sites, and particularly surrounding grain boundaries. Brittle and reduce corrosion fatigue properties. In order to reduce adverse effects on corrosion fatigue properties, the number of oxide inclusions having an average diameter of 25 ⁇ m or more per 30 g of steel material (hereinafter, sometimes referred to as “30/100 g or less”) The number of oxide inclusions is preferably 20 pieces / 100 g or less, more preferably 10 pieces / 100 g or less.In order to improve corrosion fatigue properties, oxide inclusions are required.
  • it is preferably 2/100 g or more for industrial production.
  • it is 25 ⁇ m or more, it becomes a fracture starting point as a stress concentration source and deteriorates the corrosion fatigue characteristics, but those having an average diameter of less than 25 ⁇ m do not adversely affect the corrosion fatigue characteristics.
  • Non-diffusible hydrogen content In the rolled material of the present invention, the non-diffusible hydrogen content needs to be 0.40 mass ppm or less.
  • the amount of non-diffusible hydrogen in the rolled material is large, non-diffusible hydrogen also increases in the wire after quenching and tempering. If there is a lot of non-diffusible hydrogen in the wire, the allowable amount of hydrogen that invades further before the wire becomes brittle, even a small amount of hydrogen that entered during use as a spring will cause wire embrittlement, making it easier to break early, Hydrogen brittleness resistance decreases.
  • the amount of non-diffusible hydrogen is preferably 0.35 mass ppm or less, more preferably 0.30 mass ppm or less. The smaller the amount of non-diffusible hydrogen, the better. However, it is difficult to make it 0 ppm by mass, and the lower limit is about 0.01 ppm by mass.
  • Non-diffusible hydrogen is the amount of hydrogen measured by the method described in the examples below. Specifically, it is released at 300 to 600 ° C. when the steel material is heated at 100 ° C./hour. Means the total amount of hydrogen.
  • the rolled material for high-strength springs according to the present invention is a low alloy steel in which the content of alloy elements is suppressed, and its chemical composition is as follows.
  • this invention also includes the wire which hardened and tempered after drawing the said rolling material,
  • the chemical composition is the same as the chemical composition of a rolling material. In the present specification, the chemical composition means mass%.
  • C 0.39 to 0.65%
  • C is an element necessary for ensuring the strength of the spring wire, and is also necessary for generating fine carbides that serve as hydrogen trap sites.
  • the C content is set to 0.39% or more.
  • the minimum with the preferable amount of C is 0.45% or more, More preferably, it is 0.50% or more.
  • the amount of C becomes excessive, coarse retained austenite and undissolved carbides are likely to be formed even after quenching and tempering, and hydrogen embrittlement resistance may be lowered instead.
  • C is an element that deteriorates the corrosion resistance, it is necessary to suppress the amount of C in order to enhance the corrosion fatigue characteristics of a spring product such as a suspension spring that is the final product.
  • the C content is set to 0.65% or less.
  • the upper limit with preferable C amount is 0.62% or less, More preferably, it is 0.60% or less.
  • Si 1.5-2.5%
  • Si is an element necessary for ensuring strength and has an effect of making carbide fine.
  • the Si amount was determined to be 1.5% or more.
  • the minimum with the preferable amount of Si is 1.7% or more, More preferably, it is 1.9% or more.
  • Si is an element that promotes decarburization
  • the Si amount was determined to be 2.5% or less.
  • the upper limit with preferable Si amount is 2.3% or less, More preferably, it is 2.2% or less, More preferably, it is 2.1% or less.
  • Mn 0.15 to 1.2% Mn is used as a deoxidizing element and reacts with S, which is a harmful element in steel, to form MnS, which is an element useful for detoxification of S. Mn is also an element contributing to strength improvement. In order to exhibit these effects effectively, the amount of Mn was determined to be 0.15% or more. The minimum with the preferable amount of Mn is 0.2% or more, More preferably, it is 0.3% or more. However, when the amount of Mn is excessive, the toughness is lowered and the steel material becomes brittle. From such a viewpoint, the amount of Mn was determined to be 1.2% or less. The upper limit with the preferable amount of Mn is 1.0% or less, More preferably, it is 0.85% or less.
  • P more than 0% and not more than 0.015%
  • P is a harmful element that deteriorates the ductility, for example, coiling property, of a rolled material such as a wire. Further, P is easily segregated at the grain boundary and causes embrittlement at the grain boundary, and the grain boundary is easily broken by hydrogen, which adversely affects the resistance to hydrogen embrittlement. From this point of view, the P content is set to 0.015% or less.
  • the upper limit with the preferable amount of P is 0.010% or less, More preferably, it is 0.008% or less. The smaller the amount of P, the better. However, it is usually contained in an amount of about 0.001%.
  • S more than 0% and not more than 0.015%
  • S is a harmful element that deteriorates ductility such as coiling property of the rolled material in the same manner as P described above.
  • S is easily segregated at the grain boundary and causes embrittlement of the grain boundary, and the grain boundary is easily broken by hydrogen, which adversely affects the resistance to hydrogen embrittlement.
  • the S content is set to 0.015% or less.
  • the upper limit with the preferable amount of S is 0.010% or less, More preferably, it is 0.008% or less. The smaller the amount of S, the better. However, it is usually contained in an amount of about 0.001%.
  • Al 0.001 to 0.1%
  • Al is mainly added as a deoxidizing element. Moreover, it reacts with N to form AlN to render the solid solution N harmless and contribute to the refinement of the structure.
  • the Al content is determined to be 0.001% or more.
  • the minimum with preferable Al amount is 0.002% or more, More preferably, it is 0.005% or more.
  • Al is an element that promotes decarburization in the same way as Si, it is necessary to suppress the amount of Al in spring steel containing a large amount of Si.
  • the amount of Al is set to 0.1% or less.
  • the upper limit with preferable Al amount is 0.07% or less, More preferably, it is 0.030% or less, Most preferably, it is 0.020% or less.
  • Cu 0.10 to 0.80% Cu is an element effective for suppressing surface layer decarburization and improving corrosion resistance. Therefore, the Cu amount is determined to be 0.10% or more. The minimum with the preferable amount of Cu is 0.15% or more, More preferably, it is 0.20% or more. However, if Cu is excessively contained, cracks occur during hot working or the cost increases. Therefore, the Cu amount is set to 0.80% or less. The upper limit with preferable Cu amount is 0.70% or less, More preferably, it is 0.60% or less. The amount of Cu is preferably 0.48% or less, 0.35% or less, or 0.30% or less.
  • Ni 0.10 to 0.80% Ni is an element effective for suppressing surface decarburization and improving corrosion resistance, similarly to Cu. Therefore, the amount of Ni is set to 0.10% or more.
  • the minimum with preferable Ni amount is 0.15% or more, More preferably, it is 0.20% or more. However, if Ni is excessively contained, the cost increases. Therefore, the Ni content is set to 0.80% or less.
  • the upper limit with preferable Ni amount is 0.70% or less, More preferably, it is 0.60% or less.
  • the amount of Ni is preferably 0.48% or less, 0.35% or less, or 0.30% or less.
  • the upper limit of the O amount is set to 0.0010% or less. Preferably it is 0.0008% or less, More preferably, it is 0.0006% or less. On the other hand, the lower limit of the amount of O is generally 0.0002% or more in terms of industrial production.
  • the basic components of the rolled material of the present invention are as described above, and the balance is substantially iron.
  • steel it is permissible for steel to contain inevitable impurities such as Ca, Mg, and N that are brought in depending on the situation of raw materials, materials, manufacturing equipment, and the like.
  • the rolled material for springs of the present invention has the above-mentioned chemical composition and can achieve high strength and excellent coiling properties and hydrogen embrittlement resistance, but further contains the following elements for the purpose of improving corrosion resistance depending on the application. Also good.
  • Cr more than 0% and 1.2% or less Cr is an element effective for improving corrosion resistance.
  • the Cr content is preferably 0.05% or more, more preferably 0.08% or more, and still more preferably 0.10% or more.
  • Cr has a strong tendency to generate carbides, forms unique carbides in steel, and is an element that easily dissolves in cementite at a high concentration. Although it is effective to contain a small amount of Cr, since the heating time in the quenching process is short in high-frequency heating, austenitization in which carbide, cementite and the like are dissolved in the base material tends to be insufficient.
  • the Cr content is preferably 1.2% or less, more preferably 0.8% or less, and still more preferably 0.6% or less.
  • Ti More than 0% and 0.13% or less Ti is an element useful for detoxifying S by reacting with S to form a sulfide. Ti also has the effect of forming a carbonitride to refine the structure. In order to effectively exhibit such an effect, the Ti content is preferably 0.02% or more, more preferably 0.05% or more, and further preferably 0.06% or more. However, when the amount of Ti becomes excessive, coarse Ti sulfide may be formed and ductility may deteriorate. Therefore, the Ti amount is preferably 0.13% or less. From the viewpoint of cost reduction, the content is preferably 0.10% or less, and more preferably 0.09% or less.
  • B More than 0% and 0.01% or less B is an element that improves hardenability, has an effect of strengthening the prior austenite grain boundary, and contributes to suppression of fracture.
  • the B content is preferably 0.0005% or more, more preferably 0.0010% or more.
  • the amount of B is preferably 0.01% or less, more preferably 0.0050% or less, and still more preferably 0.0040% or less.
  • Nb more than 0%, less than 0.1% and Mo: more than 0%, less than 0.5%
  • Nb is an element that forms carbonitrides with C and N and contributes mainly to refinement of the structure It is.
  • the Nb content is preferably 0.003% or more, more preferably 0.005% or more, and still more preferably 0.01% or more.
  • the Nb amount is preferably 0.1% or less. From the viewpoint of cost reduction, it is preferably 0.07% or less.
  • Mo like Nb, forms carbonitrides with C and N, and is an element that contributes to refinement of the structure. It is also an effective element for securing strength after tempering.
  • the Mo amount is preferably 0.15% or more, more preferably 0.20% or more, and further preferably 0.25% or more.
  • the Mo amount is preferably 0.5% or less, and more preferably 0.4% or less.
  • Nb and Mo may be contained alone or in combination of two kinds.
  • the rolled material of the present invention contains N as an inevitable impurity, and this amount is preferably adjusted to the following range.
  • N more than 0%, 0.007% or less
  • N amount is an element contained in inevitable impurities, but as the amount increases, coarse nitrides are formed together with Ti and Al, which adversely affects fatigue properties. Preferably as little as possible.
  • the N amount may be, for example, 0.007% or less, and more preferably 0.005% or less.
  • the productivity is significantly reduced.
  • N also forms nitrides with Al and contributes to the refinement of crystal grains. From such a viewpoint, the N content is preferably 0.001% or more, more preferably 0.002% or more, and further preferably 0.003% or more.
  • a degassing process is performed by a molten steel process, and the amount of hydrogen in the molten steel is set to 2.5 mass ppm or less.
  • a vacuum tank equipped with two dip tubes is installed in the ladle, Ar gas is blown from the side of one dip tube, and the buoyancy is used to circulate the molten steel to the vacuum tank. It is effective to perform degassing. This method is excellent in hydrogen removal capability.
  • the amount of hydrogen in the molten steel is preferably 2.0 mass ppm or less, more preferably 1.5 mass ppm or less, and particularly preferably 1.0 mass ppm or less.
  • the homogenization treatment (heating) before the bulk rolling is performed at 1100 ° C. or higher, preferably 1200 ° C. or higher for 10 hours or longer.
  • the average cooling rate from 400 to 100 ° C. after hot rolling is 0.5 ° C./second or less, preferably 0.3 ° C./second or less.
  • cooling conditions other than the coil winding temperature TL after hot rolling and the temperature range of 400 to 100 ° C. after winding are not particularly limited.
  • the coil winding temperature TL can be, for example, 900 ° C. or higher and 1000 ° C. or lower, preferably 910 ° C. or higher, more preferably 930 ° C. or higher.
  • the average cooling rate at the coil winding temperature TL to 650 ° C. can be 2 ° C./second or more and 5 ° C./second or less.
  • the lower limit of the average cooling rate at the coil winding temperature TL to 650 ° C. is preferably 2.3 ° C./second or more, more preferably 2.5 ° C./second or more.
  • the average cooling rate of 650 to 400 ° C. can be 2 ° C./second or less.
  • the average cooling rate of 650 to 400 ° C. is preferably 1.5 ° C./second or less, more preferably 1 ° C./second or less.
  • the minimum of this average cooling rate is not specifically limited, For example, it is about 0.3 degree-C / sec.
  • oxide inclusions In order to reduce oxide inclusions, it is necessary to make the oxygen content of the wire below a specified value. Further, by sufficiently deoxidizing with aluminum or silicon and sufficiently degassing, inclusions can be reduced, high cleaning can be achieved, and oxide inclusions can be reduced.
  • a high-strength wire having a tensile strength of 1900 MPa or more can be obtained by subjecting a rolled material to wire processing, that is, wire drawing, followed by quenching and tempering by induction heating or the like.
  • the rolled material is drawn at a reduction in area of about 5 to 35%, then quenched at about 900 to 1000 ° C., and tempered at about 300 to 520 ° C.
  • the quenching temperature is preferably 900 ° C. or higher in order to sufficiently austenite, and 1000 ° C. or lower is preferable in order to prevent crystal grain coarsening.
  • the tempering heating temperature may be set to an appropriate temperature in the range of 300 to 520 ° C. according to the target value of the wire strength.
  • the quenching and tempering time is about 10 to 60 seconds, respectively.
  • the structure after quenching and tempering needs to have a tempered martensite structure of 80 area% or more. When the ratio of undissolved ferrite and retained austenite in the structure increases, the strength decreases.
  • the structure after quenching and tempering preferably has a tempered martensite structure of 85 area% or more. In order to set the ratio of the tempered martensite structure to 80% by area or more, it is preferable to heat to 900 ° C. or higher during quenching and sufficiently austenite, and then cool to 100 ° C. or lower by water cooling or oil cooling.
  • the wire of the present invention thus obtained can realize a high tensile strength of 1900 MPa or more.
  • the tensile strength may be selected according to the spring design strength, and is usually selected from 1900 MPa to 2200 MPa.
  • the upper limit of the tensile strength is not particularly limited, but is approximately 2500 MPa.
  • the wire of the present invention uses the rolled material of the present invention, it can exhibit excellent corrosion fatigue characteristics even at a high strength of 1900 MPa or more.
  • the coil winding temperature TL after the hot rolling is 950 ° C.
  • the other cooling after the winding is an average cooling rate of 4 ° C./second from TL to 650 ° C., and 1 ° C. from 650 to 400 ° C. Cooled at an average cooling rate of / sec.
  • the homogenization treatment at 1100 ° C. is performed for 10 hours or more, and in the test example described as “ ⁇ ”, the time for the homogenization treatment at 1100 ° C. Is less than 10 hours.
  • the obtained wire was measured for the amount of non-diffusible hydrogen and the number of oxide inclusions in the following manner. The results are shown in Tables 4-6.
  • Tables 4 to 6 the number of oxide inclusions having an average diameter of 25 ⁇ m or more in the rolled material is expressed as “the number of inclusions having a diameter of 25 ⁇ m or more in the rolled material”.
  • Non-diffusible hydrogen amount A test piece having a width of 20 mm and a length of 40 mm was cut out from the rolled material, that is, the wire. Using a gas chromatography apparatus, the test piece was heated at a temperature increase rate of 100 ° C./hour, and the amount of released hydrogen at 300 to 600 ° C. was measured, which was defined as the amount of non-diffusible hydrogen.
  • the number of oxide inclusions was calculated by calculating the average value of the results of investigating six 50 g rolled material samples and converting them to the number per 100 g.
  • the number of inclusions was investigated by the acid dissolution method.
  • the 50 g sample is dissolved with an acid, the undissolved inclusions remain on the filter paper, and inclusions having an average diameter of 25 ⁇ m or more are selected by EPMA, and EDX (Energy Dispersive X-ray spectroscopy: energy dispersive X (Line analysis), and oxide inclusions were selected.
  • the number of oxide inclusions having an average diameter of 25 ⁇ m or more was measured to obtain an average value thereof and converted into the number per 100 g of steel material.
  • the average diameter of the oxide inclusions means an average value of the major axis and the minor axis, that is, a value obtained by dividing the sum of the major axis and the minor axis by 2.
  • sufficient vacuum degassing was performed during the melting of the converter to remove oxygen.
  • the wire was drawn to a diameter of 12.5 mm, that is, cold drawn and quenched and tempered.
  • the area reduction rate of the wire drawing is about 23.6%, and the conditions for quenching and tempering are as follows.
  • Quenching and tempering conditions ⁇ High-frequency heating ⁇ Heating rate: 200 ° C./second ⁇ Quenching: 950 ° C., 20 seconds, water cooling / tempering: 300 to 520 ° C., 20 seconds, water cooling
  • Corrosion fatigue properties were evaluated by the Ono rotary bending fatigue test after corrosion treatment and the fracture life.
  • the test piece cut the quenched and tempered wire to produce a No. 1 test piece of JIS Z 2274 (1978).
  • the parallel part of the test piece was polished with # 800 emery paper. The test was performed without performing shot peening on the surface. First, the processed test piece was subjected to corrosion treatment under the following conditions.
  • Corrosion treatment 35 ° C, 5% NaCl solution sprayed with salt water for 8 hours, then dried and kept in a humid environment at 35 ° C and relative humidity of 60% for 16 hours.
  • the test piece was subjected to corrosion treatment by repeating 10 cycles.
  • the test piece after the corrosion treatment was subjected to a rotating bending test to evaluate the corrosion fatigue characteristics.
  • Ten test pieces were used for each test, and the Ono type rotating bending fatigue test was performed with the load stress set to 500 MPa. The fatigue life until each test piece was broken was measured.
  • the average value of fatigue life in 10 test pieces was measured, and the average fatigue life value of 100,000 times or more was evaluated as being excellent in corrosion fatigue life.
  • test No. shown in Table 5 Nos. 17 to 31 are inferior in corrosion fatigue properties because at least one of the chemical composition of the steel material specified in the present invention, the number of oxide inclusions, and the non-diffusible hydrogen content is inappropriate. ing.
  • Test No. 17 and 18 are examples using steel types 17 and 18 in which Cu or Ni is not added or less than the specified lower limit, and the corrosion fatigue characteristics are deteriorated.
  • Test No. Nos. 30 and 31 have insufficient deoxidation treatment, and the amount of O in the steel is excessive, and none of the non-diffusible hydrogen reduction treatment described above is performed, so oxide inclusions in the rolled material And the amount of non-diffusible hydrogen in the rolled material increased, and in all cases, the fatigue life was less than 100,000 times and the corrosion fatigue characteristics deteriorated.
  • the rolled material and wire of the present invention can be suitably used for coil springs used in automobiles and the like, for example, valve springs and suspension springs used in engines and suspensions, etc., and are industrially useful.

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PCT/JP2015/052960 2014-02-28 2015-02-03 高強度ばね用圧延材および高強度ばね用ワイヤ WO2015129403A1 (ja)

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MX2016011156A MX2016011156A (es) 2014-02-28 2015-02-03 Material laminado para resorte de alta resistencia y cable para resorte de alta resistencia.
CN201580010254.4A CN106062229B (zh) 2014-02-28 2015-02-03 高强度弹簧用轧制材和高强度弹簧用钢丝
EP15755898.2A EP3112491A4 (en) 2014-02-28 2015-02-03 Rolled material for high strength spring, and wire for high strength spring
US15/120,168 US20170058376A1 (en) 2014-02-28 2015-02-03 Rolled material for high strength spring, and wire for high strength spring
KR1020167024864A KR20160119216A (ko) 2014-02-28 2015-02-03 고강도 스프링용 압연재 및 고강도 스프링용 와이어

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108474086A (zh) * 2016-01-26 2018-08-31 新日铁住金株式会社 弹簧钢
WO2022048822A1 (en) * 2020-09-03 2022-03-10 Nv Bekaert Sa A steel cord for rubber reinforcement
CN115125446A (zh) * 2022-06-28 2022-09-30 浙江伊思灵双第弹簧有限公司 一种汽车用高疲劳性能弹簧及其制备方法

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6212473B2 (ja) * 2013-12-27 2017-10-11 株式会社神戸製鋼所 高強度ばね用圧延材及びこれを用いた高強度ばね用ワイヤ
JP6458927B2 (ja) * 2014-10-07 2019-01-30 大同特殊鋼株式会社 線材圧延性に優れた高強度ばね鋼
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US20230296152A1 (en) * 2019-10-16 2023-09-21 Nippon Steel Corporation Damper spring
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KR102141331B1 (ko) * 2020-03-19 2020-08-04 주식회사 샤크컴퍼니 강선을 이용하여 만든 파이프형 금속 탄성체 및 그 제조 방법과 이를 이용한 낚시릴의 텐션조정노브
CN112853220A (zh) * 2021-01-08 2021-05-28 江苏省沙钢钢铁研究院有限公司 2000MPa级弹簧用盘条及其生产方法
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006104506A (ja) * 2004-10-01 2006-04-20 Kobe Steel Ltd 疲労強度または冷間加工性に優れた高清浄度鋼の製造方法
JP2007191776A (ja) * 2006-01-23 2007-08-02 Kobe Steel Ltd 耐脆性破壊特性に優れた高強度ばね鋼およびその製造方法
KR100833051B1 (ko) * 2006-12-20 2008-05-27 주식회사 포스코 고강도 스프링용 강선재, 상기 강선재의 제조방법
JP2009046764A (ja) * 2007-07-20 2009-03-05 Kobe Steel Ltd 腐食疲労特性に優れたばね用鋼
CN102560046A (zh) * 2012-02-21 2012-07-11 南京钢铁股份有限公司 一种弹簧钢线材表面脱碳的控制方法
JP2012172247A (ja) * 2011-02-24 2012-09-10 Nippon Steel Corp 耐水素脆化特性に優れた高強度ばね用鋼
WO2013179934A1 (ja) * 2012-05-31 2013-12-05 株式会社神戸製鋼所 コイリング性と耐水素脆性に優れた高強度ばね用鋼線およびその製造方法

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5776267A (en) * 1995-10-27 1998-07-07 Kabushiki Kaisha Kobe Seiko Sho Spring steel with excellent resistance to hydrogen embrittlement and fatigue
JP3764715B2 (ja) 2002-10-22 2006-04-12 新日本製鐵株式会社 高強度冷間成形ばね用鋼線とその製造方法
US7615186B2 (en) * 2003-03-28 2009-11-10 Kobe Steel, Ltd. Spring steel excellent in sag resistance and fatigue property
JP4280123B2 (ja) * 2003-07-01 2009-06-17 株式会社神戸製鋼所 耐腐食疲労性に優れたばね用鋼
JP4555768B2 (ja) 2004-11-30 2010-10-06 新日本製鐵株式会社 高強度ばね用鋼線
JP4423253B2 (ja) * 2005-11-02 2010-03-03 株式会社神戸製鋼所 耐水素脆化特性に優れたばね用鋼、並びに該鋼から得られる鋼線及びばね
JP4393467B2 (ja) 2006-02-28 2010-01-06 株式会社神戸製鋼所 強伸線加工用の熱間圧延線材およびその製造方法
JP4134203B2 (ja) * 2006-06-09 2008-08-20 株式会社神戸製鋼所 疲労特性に優れた高清浄度ばね用鋼および高清浄度ばね
US8613809B2 (en) * 2006-06-09 2013-12-24 Kobe Steel, Ltd. High cleanliness spring steel and high cleanliness spring excellent in fatigue properties
JP5331698B2 (ja) * 2006-10-11 2013-10-30 ポスコ 冷間加工性に優れた高強度・高靭性のばね用鋼線材、その鋼線材の製造方法及びその鋼線材でばねを製造する方法
CN102268604A (zh) * 2007-07-20 2011-12-07 株式会社神户制钢所 弹簧用钢线材及其制造方法
JP4900516B2 (ja) * 2010-03-29 2012-03-21 Ｊｆｅスチール株式会社 ばね鋼およびその製造方法
CN103484781B (zh) * 2013-09-26 2016-06-01 宝山钢铁股份有限公司 一种高强高韧性弹簧钢及其制造方法
JP6212473B2 (ja) * 2013-12-27 2017-10-11 株式会社神戸製鋼所 高強度ばね用圧延材及びこれを用いた高強度ばね用ワイヤ

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006104506A (ja) * 2004-10-01 2006-04-20 Kobe Steel Ltd 疲労強度または冷間加工性に優れた高清浄度鋼の製造方法
JP2007191776A (ja) * 2006-01-23 2007-08-02 Kobe Steel Ltd 耐脆性破壊特性に優れた高強度ばね鋼およびその製造方法
KR100833051B1 (ko) * 2006-12-20 2008-05-27 주식회사 포스코 고강도 스프링용 강선재, 상기 강선재의 제조방법
JP2009046764A (ja) * 2007-07-20 2009-03-05 Kobe Steel Ltd 腐食疲労特性に優れたばね用鋼
JP2012172247A (ja) * 2011-02-24 2012-09-10 Nippon Steel Corp 耐水素脆化特性に優れた高強度ばね用鋼
CN102560046A (zh) * 2012-02-21 2012-07-11 南京钢铁股份有限公司 一种弹簧钢线材表面脱碳的控制方法
WO2013179934A1 (ja) * 2012-05-31 2013-12-05 株式会社神戸製鋼所 コイリング性と耐水素脆性に優れた高強度ばね用鋼線およびその製造方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3112491A4 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108474086A (zh) * 2016-01-26 2018-08-31 新日铁住金株式会社 弹簧钢
EP3409810A4 (en) * 2016-01-26 2019-07-31 Nippon Steel Corporation SPRING STEEL
US11390936B2 (en) 2016-01-26 2022-07-19 Nippon Steel Corporation Spring steel
WO2022048822A1 (en) * 2020-09-03 2022-03-10 Nv Bekaert Sa A steel cord for rubber reinforcement
CN115125446A (zh) * 2022-06-28 2022-09-30 浙江伊思灵双第弹簧有限公司 一种汽车用高疲劳性能弹簧及其制备方法

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