WO2018212327A1 - Fil, fil d'acier et procédé de fabrication d'un fil d'acier - Google Patents

Fil, fil d'acier et procédé de fabrication d'un fil d'acier Download PDF

Info

Publication number
WO2018212327A1
WO2018212327A1 PCT/JP2018/019306 JP2018019306W WO2018212327A1 WO 2018212327 A1 WO2018212327 A1 WO 2018212327A1 JP 2018019306 W JP2018019306 W JP 2018019306W WO 2018212327 A1 WO2018212327 A1 WO 2018212327A1
Authority
WO
WIPO (PCT)
Prior art keywords
wire
less
ferrite
cooling
steel
Prior art date
Application number
PCT/JP2018/019306
Other languages
English (en)
Japanese (ja)
Inventor
俊彦 手島
直樹 松井
新 磯
Original Assignee
新日鐵住金株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 新日鐵住金株式会社 filed Critical 新日鐵住金株式会社
Priority to JP2018566321A priority Critical patent/JP6528920B2/ja
Priority to CN201880032132.9A priority patent/CN110621799B/zh
Priority to KR1020197034857A priority patent/KR102303599B1/ko
Priority to MYPI2019006718A priority patent/MY196779A/en
Publication of WO2018212327A1 publication Critical patent/WO2018212327A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—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
    • 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
    • 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

Definitions

  • the present invention relates to a wire, a steel wire, and a method for manufacturing a steel wire.
  • the present invention is widely used as a material for high-strength steel wires used as wires for reinforcing tires for automobiles, reinforcing wires such as aluminum transmission lines, PC steel wires, rope wires used for bridges, etc. It relates to the wire used. Moreover, this invention relates to the manufacturing method of the steel wire using this wire, and the steel wire obtained from this wire.
  • the wire is manufactured by hot rolling and processed into a wire by drawing to a predetermined wire diameter. Since the patenting process is performed once or twice in the middle of the wire drawing process to draw a thin steel wire, the wire material is required to have high wire drawing workability.
  • Patent Document 1 Japanese Patent Application Laid-Open No. 2014-055316 discloses a high-strength steel wire in which 50% or more of lamellar cementite having an aspect ratio of 10 or more is present on the number basis with respect to the total number of lamellar cementite.
  • a wire rod for high-strength steel wire has been proposed, which is a wire rod for use in such a lamellar cementite and prevents a reduction in wire drawing workability.
  • Patent Document 2 Japanese Patent Application Laid-Open No. 2000-119756 includes pearlite in which the fraction of pro-eutectoid ferrite is 10% or less and the remainder is formed by discontinuous cementite. By configuring, a wire rod for high-strength steel wire that has prevented wire drawing workability from being deteriorated has been proposed.
  • wire breakage is difficult to occur in a process of manufacturing a steel wire having a large diameter (for example, wire diameter of 0.5 mm or more) by drawing to a high degree of wiredrawing, and the torsional characteristics after wire drawing are low. Realization of a good wire rod is desired.
  • the present invention has been made in view of the above circumstances, and is suitable as a material for large diameter wires and the like, and suppresses disconnection during wire drawing of a steel wire having high strength and excellent torsional characteristics. It is an object of the present invention to provide a wire that can be manufactured stably. Moreover, this invention makes it a subject to provide the steel wire which has high intensity
  • the present inventors conducted various studies in order to solve the above-described problems. As a result, the following knowledge was obtained.
  • the present inventors examined means for improving the subgrain boundary density.
  • Subgrain boundaries are considered to be introduced in order to eliminate misfits of both phases when lamellar ferrite and lamellar cementite (hereinafter referred to as lamellar cementite) in a pearlite structure grow cooperatively during pearlite transformation.
  • lamellar cementite lamellar cementite
  • the present inventors have found that the subgrain boundary density can be adjusted by using the pearlite transformation temperature and the content of an alloy element (for example, Si) that dissolves in lamella ferrite.
  • the wire obtained by adjusting the alloying element content and the adjustment cooling conditions after hot rolling and increasing the large-angle grain boundary density and sub-grain boundary density is another wire material having the same strength level.
  • the present inventors have found that the wire drawing workability and the twisting property after wire drawing are superior.
  • the present invention has been completed based on the above findings, and the gist thereof is as follows.
  • the wire according to one embodiment of the present invention has a chemical composition of mass%, C: 0.30 to 0.75%, Si: 0.80 to 2.00%, Mn: 0.30 to 1 0.00%, N: 0.0080% or less, P: 0.030% or less, S: 0.020% or less, O: 0.0070% or less, Al: 0 to 0.050%, Cr: 0 to 1 0.00%, V: 0 to 0.15%, Ti: 0 to 0.050%, Nb: 0 to 0.050%, B: 0 to 0.0040%, Ca: 0 to 0.0050%, and Mg: 0 to 0.0040%, the balance being Fe and impurities, the surface layer portion having a depth in the range of 150 to 400 ⁇ m from the surface of the wire, and the diameter of the wire from the central axis of the wire
  • the main structure is a pearlite structure both in the center part that is within the
  • the density ⁇ 1 of the sub-boundary that is less than 15 ° is 70 / mm ⁇ ⁇ 1 ⁇ 600 / mm, and the density ⁇ 2 of the large-angle grain boundary that has an angle difference of 15 ° or more of the ferrite crystal orientation in the entire structure is 200. / Mm or more.
  • the chemical composition may contain Al: 0.010 to 0.050% by mass.
  • the chemical composition may contain Cr: 0.05 to 1.00% by mass.
  • the chemical composition is, in mass%, V: 0.005 to 0.15%, Ti: 0.002 to 0.00.
  • the chemical composition may contain B: 0.0001 to 0.0040% by mass%.
  • the chemical composition is Ca: 0.0002 to 0.0050% and Mg: 0.0002 to 0 by mass%.
  • One or two selected from the group consisting of .0040% may be contained.
  • the density ⁇ 1 of the sub-boundary in the surface layer portion and the central portion of the wire satisfies the following formula 1. Also good.
  • Formula 1 (C) in the formula 1 is the C content in mass% in the chemical composition of the wire.
  • the diameter of the wire may be 3.5 to 7.0 mm.
  • the wire according to any one of (1) to (8) may be used as a material for a steel wire.
  • a steel wire according to another aspect of the present invention is produced by drawing a wire according to any one of (1) to (9) above, and has a diameter of 0.5 to 1.. 5 mm.
  • a method of manufacturing a steel wire according to another aspect of the present invention includes a step of drawing a wire according to any one of (1) to (9) to obtain a steel wire, The diameter of the steel wire is 0.5 to 1.5 mm.
  • a steel wire having high strength suitable for a material such as a wire and excellent torsional characteristics can be stably manufactured while suppressing disconnection during wire drawing.
  • Very useful Since the steel wire which concerns on 1 aspect of this invention has high intensity
  • the method of manufacturing a steel wire according to an aspect of the present invention can stably manufacture a steel wire having high strength suitable for a wire material and excellent torsional characteristics while suppressing disconnection during wire drawing, It is extremely useful in industry.
  • a range of 150 to 400 ⁇ m in depth from the surface of the wire is defined as the surface layer portion 11, and the diameter d of the wire from the central axis of the wire. Is defined as the central portion 12.
  • a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
  • the wire of the present embodiment is a steel wire material suitable as a material for a wire that is a reinforcing material for tires of automobiles, a reinforcing wire such as an aluminum power transmission line, a PC steel wire, a rope wire used for a bridge, etc. It can be used as a wire rod.
  • the wire drawing workability of a wire is an index indicating the difficulty of occurrence of disconnection when a wire is drawn to obtain a steel wire.
  • the torsional characteristics after wire drawing of wire include the difficulty of delamination and the difficulty of torsional breakage when a torsion test is performed on a steel wire obtained by wire drawing. It is an index showing.
  • the wire according to the present embodiment preferably has a wire drawing workability such that 50 kg of a wire having a diameter of 6.0 mm is prepared and the number of breaks when the wire is drawn to a diameter of 0.5 mm is zero. . Furthermore, it is preferable that the steel wire after wire drawing has a tensile strength of 2800 MPa or more. Moreover, it is preferable that the steel wire used for the wire has a torsion characteristic in which delamination does not occur even once even if ten torsion tests are performed and the average value of the number of twists is 23 times or more. It can be determined that a steel wire having a twist number of 23 or more has sufficient ductility not to break by handling such as straightening after wire drawing.
  • C 0.30 to 0.75%
  • C is an element that strengthens steel. In order to obtain this effect, C must be contained in an amount of 0.30% or more.
  • the C content exceeds 0.75%, the cementite fraction increases and the wire drawing workability decreases. Therefore, the appropriate C content is 0.30% or more and 0.75% or less.
  • the C content is preferably 0.35% or more, and more preferably 0.40% or more.
  • the C content is preferably less than 0.75% or 0.70% or less, and more preferably 0.65% or less.
  • the C content may be 0.42% or more, or 0.45% or more.
  • the C content may be 0.60% or less, or 0.55% or less.
  • Si 0.80 to 2.00%
  • Si is a component that not only increases the strength of the wire but also contributes to an increase in subgrain boundary density. However, if the Si content of the wire is less than 0.80%, the effect of increasing the sub-boundary density due to containing Si cannot be sufficiently obtained. On the other hand, if the Si content of the wire exceeds 2.00%, the ferrite fraction increases and the wire drawing workability decreases. Therefore, the Si content of the wire is determined to be in the range of 0.80 to 2.00%. In order to stably obtain a wire having a desired microstructure, the Si content of the wire may be 1.00% or more, 1.15% or more, 1.30% or more, or 1.50% or more. . The Si content of the wire may be 1.90% or less, 1.80% or less, 1.75% or less, or 1.70% or less.
  • Mn 0.30 to 1.00%
  • Mn is an element having an effect of preventing hot brittleness of the steel wire by fixing S in the steel as MnS in addition to the effect of increasing the strength of the steel wire.
  • the Mn content is preferably 0.35% or more, more preferably 0.40% or more.
  • the Mn content may be 0.50% or more, or 0.55% or more.
  • Mn is an element that easily segregates.
  • Mn is contained exceeding 1.00%, Mn is concentrated particularly in the central portion, martensite and bainite are generated in the central portion, and wire drawing workability is lowered. In addition, the formation of coarse MnS also contributes to a decrease in wire drawing workability.
  • Mn is preferably 0.90% or less, and more preferably 0.80% or less.
  • the Mn content may be 0.75% or less, or 0.70% or less.
  • N 0.0080% or less
  • N is an element that lowers torsional characteristics while increasing the strength of the wire by fixing to dislocations during cold wire drawing.
  • the N content of the wire is regulated to 0.0080% or less.
  • the upper limit with preferable N content is 0.0060% or less or 0.0050% or less.
  • the lower the N content, the better, and N may not be contained in the wire.
  • the N content may be 0.0045% or less, or 0.0040% or less.
  • the N content may be 0.0010% or more, or 0.0025% or more.
  • P 0.030% or less
  • P is an element that segregates at the grain boundary of the wire and deteriorates torsional characteristics.
  • the upper limit of the P content is preferably 0.025% or less.
  • the lower the P content the better. P may not be contained in the wire.
  • the P content may be 0.020% or less, 0.015% or less, or 0.010% or less.
  • the P content may be 0.002% or more, 0.005% or more, or 0.008% or more.
  • S 0.020% or less S is an element that forms MnS and degrades the wire drawing workability. And when S content of a wire exceeds 0.020%, the fall of wire drawing workability will become remarkable. For this reason, the S content of the wire is regulated to 0.020% or less.
  • the upper limit with preferable S content is 0.010% or less. The lower the S content, the better. S may not be contained in the wire.
  • the S content may be 0.015% or less, 0.008% or less, or 0.005% or less.
  • the S content may be 0.001% or more, 0.002% or more, or 0.005% or more.
  • O is an element that reduces the ductility of the wire by forming an oxide.
  • the O content of the wire exceeds 0.0070%, the torsional characteristics are significantly deteriorated. Therefore, the O content of the wire is regulated to 0.0070% or less.
  • the upper limit of the O content is preferably 0.0050% or less. The lower the O content, the better, and O may not be contained in the wire.
  • the O content may be 0.0005% or more, or 0.0010% or more.
  • the O content may be 0.0045% or less, or 0.0040% or less.
  • the surface layer portion and the central portion of the wire have a pearlite structure as a main structure, and the cross-sectional area of the wire has an area ratio of 45% or less as a ferrite structure, and a non-pearlite and non-ferrite structure has an area ratio as 5% or less.
  • the subgrain boundary density ⁇ 1 at which the angle difference of the crystal orientation of the lamellar ferrite is 2 ° or more and less than 15 ° is 70 / mm ⁇ ⁇ 1 ⁇ 600 / mm, and the angle difference of the ferrite crystal orientation in the entire structure is 15 ° or more. It is necessary to have a metal structure with a large-angle grain boundary density ⁇ 2 of 200 / mm or more.
  • the “main structure” means a structure occupying the largest area ratio in the metal structure.
  • the “area ratio” means an area ratio measured in a cross section perpendicular to the length direction of the wire, and the measurement method will be described later.
  • the surface layer part and the center part of the wire according to the present embodiment include a pearlite structure in an area ratio of 50% or more.
  • the wire having such a metal structure in the surface layer portion and the center portion has a high drawing value during a tensile test and is excellent in wire drawing workability. Moreover, according to the wire having such a metal structure in the surface layer portion and the center portion, when this is drawn into a steel wire having a diameter of 1 mm or less and its tensile strength is 2800 MPa or more, excellent torsional characteristics are obtained. The steel wire which has is obtained. In the metal structure of the wire rod, the remaining main structure (non-pearlite and non-ferrite structure) excluding ferrite structure and pearlite structure is bainite, martensite, and the like.
  • pearlite exhibits a lamellar structure in which lamellar ferrite and lamellar cementite are arranged in layers by a eutectoid reaction generated from austenite, and a hierarchical substructure is formed therein.
  • a region surrounded by a large-angle grain boundary is referred to as a block, and a region having the same lamella orientation in the block is referred to as a colony.
  • a structure in which a cementite plate is dispersed in each grain of a ferrite structure while having some orientation is pearlite.
  • FIG. 2 shows a schematic diagram of an example in which the pearlite structure is simplified.
  • a block surrounded by a curved large-angle grain boundary 22 is generated starting from an old ⁇ grain boundary 21 (former austenite grain boundary), and a sub-grain boundary 23 is formed in the block. Is formed.
  • the crystal orientation in the block is changed to many random orientations, and in the structure of FIG. 2, the total length of chain lines indicating the subgrain boundaries 23 can be recognized as the total length of the subgrain boundaries 23.
  • FIG. 2 shows a schematic diagram of an example in which the pearlite structure is simplified.
  • the total length of the large-angle grain boundaries 22 constituting the outer periphery of the block (the length of the thick solid line surrounding the block) can be recognized as the length of the large-angle grain boundaries 22.
  • the layered structure of lamellar cementite 31 and lamellar ferrite 32 constituting the lamellar structure is enlarged and displayed.
  • the “pearlite structure” of the wire according to the present embodiment includes a so-called pseudo pearlite structure (a pearlite structure generated without the lamellar cementite 31 growing in a plate shape).
  • the pseudo pearlite structure is different from a normal pearlite structure in that the lamella cementite 31 is observed to be divided in the block when observed with an SEM.
  • the pearlite structure and the pseudo pearlite structure are handled as the same.
  • the subgrain boundaries and the large angle grain boundaries are It is defined as follows.
  • the boundary surface where the difference in crystal orientation between adjacent lamellar ferrites is 2 ° or more and less than 15 ° is called a sub-boundary, and the length of the sub-boundary per unit area of pearlite in the inspection visual field The total is called subgrain boundary density ⁇ 1>.
  • the boundary surface where the angle difference between adjacent ferrite crystal orientations is 15 ° or more in the entire structure is called a large-angle grain boundary
  • the total length of the large-angle grain boundaries per unit area of the inspection field is the large-angle grain boundary density. It is referred to as ⁇ 2>.
  • the ferrite used for specifying the large-angle grain boundary includes both a normal ferrite structure and a lamellar ferrite constituting a pearlite structure. Each measuring method will be described later.
  • ⁇ Area ratio of ferrite structure and area ratio of non-pearlite and non-ferrite structure The area ratio of the ferrite structure in the cross section of the wire must be 45% or less for both the wire center and the surface layer. When it exceeds 45% at the center of the wire, ferrite is precipitated in a massive and coarse manner, so that the wire drawing workability is lowered. Further, when the area ratio of the ferrite structure is more than 45% in the surface portion of the wire, the number of twists after the wire drawing process is reduced. This is presumably because deformation concentrates on the ferrite portion of the surface layer portion. Note that it is not necessary to particularly define the lower limit value of the area ratio of the ferrite structure.
  • the area ratio of the ferrite structure may be 0% in the center portion or the surface layer portion of the wire.
  • the area ratio of ferrite may be 43% or less, 40% or less, 35% or less, or 30% or less in the center portion or the surface layer portion of the wire.
  • the area ratio of ferrite may be 10% or more, 15% or more, 20% or more, or 27% or more.
  • the area ratio of non-ferrite and non-pearlite structure needs to be 5% or less. In other words, the total area ratio of the ferrite structure and the pearlite structure needs to be more than 95%.
  • the lower limit of the area ratio of non-ferrite and non-pearlite structure need not be specified.
  • the area ratio of the non-ferrite and non-pearlite structure may be 0% in the center portion or the surface layer portion of the wire. That is, the total area ratio of the ferrite structure and the pearlite structure may be 100%.
  • the area ratio of non-ferrite and non-pearlite structure is 4% or less, 3% or less, 2% or less, or 1% or less (that is, the total area ratio of ferrite structure and pearlite structure is more than 96%, more than 97%, 98% Or over 99%).
  • the area ratio of the non-ferrite and non-pearlite structure may be 1% or more, or 2% or more (that is, the total area ratio of the ferrite structure and the pearlite structure is less than 99% or less than 98%).
  • the subgrain boundary density ⁇ 1 (subgrain boundary density at which the angle difference between the crystal orientations of the lamellar ferrite in the pearlite structure is 2 ° or more and less than 15 °) is 70 / mm to 600 / mm. Need to be.
  • the subgrain boundary density By setting the subgrain boundary density to 70 / mm or more in the center part and the surface layer part of the wire, it is possible to suppress variations in the strength of the steel wire after wire drawing and to reduce localization of deformation during the torsion test. Therefore, good torsional characteristics can be obtained even with a high-strength steel wire. On the contrary, when the subgrain boundary density is less than 70 / mm at the center part and the surface layer part of the wire, the torsional characteristics are not improved when the tensile strength of the steel wire obtained after the wire drawing is 2800 MPa or more.
  • the torsional characteristics tend to decrease as described above, and the sub-boundary density at the center portion and the surface layer portion of the wire at this time was over 600 / mm. It is preferable to set the upper limit of 600 / mm. For this reason, the density of the sub-boundary where the difference in crystal orientation of the lamellar ferrite in the pearlite structure is 2 ° or more and less than 15 ° in the center portion and the surface layer portion of the wire is in the range of 70 / mm to 600 / mm. To do.
  • the subgrain boundary density is preferably 100 / mm or more, and more preferably 120 / mm or more.
  • the subgrain boundary density may be 150 / mm or more, or 180 / mm or more in the surface layer portion or the center portion of the wire.
  • the subgrain boundary density may be 550 / mm or less, 500 / mm or less, 400 / mm or less, or 350 / mm or less in the surface layer portion or the center portion of the wire.
  • the subgrain boundary density ⁇ 1 preferably satisfies the following formula 1.
  • (C) in Formula 1 is the C content in unit mass% in the chemical composition of the wire. 220 ⁇ (C) +100 ⁇ 1 ⁇ 220 ⁇ (C) +300: Formula 1 As the C content in the chemical composition of the wire increases, the area ratio of the ferrite structure in the surface layer portion and the center of the wire decreases, and the area ratio of the pearlite structure increases. It is considered that as the area ratio of the pearlite structure increases, the growth distance of cementite increases and subgrain boundaries are more easily introduced into the pearlite structure.
  • the present inventors considered that the preferable range of the subgrain boundary density depends on the C content in the chemical composition of the wire. According to the knowledge of the present inventors, when the subgrain boundary density satisfies the above formula 1 in the surface layer portion and the center portion of the wire, the twist characteristics are further improved by reducing the variation in the twist value of the wire. Is done.
  • the large-angle grain boundary density ⁇ 2 (the density of the large-angle grain boundary where the angle difference of the ferrite crystal orientation is 15 ° or more) needs to be 200 / mm or more.
  • the large-angle grain boundary density is sufficiently high, the ductility of the wire is high, and the formation of coarse cracks during wire drawing can be suppressed, so that wire drawing workability is improved.
  • the large-angle grain boundary density is less than 200 / mm in the surface layer portion and the center portion of the wire rod, the wire drawing workability is lowered.
  • the density of the large-angle grain boundaries having an angle difference of 15 ° or more in the ferrite crystal orientation is set in the range of 200 / mm or more.
  • the large angle grain boundary density is preferably 230 / mm or more.
  • the upper limit of the large-angle grain boundary density in the surface layer part or the center part of the wire is not particularly defined, but since it is difficult to produce a large-angle grain boundary density of 500 / mm or more, the large-angle grain in the surface layer part or the center part of the wire It is preferable that the upper limit of the field density is 500 / mm.
  • the large-angle grain boundary density in the surface layer portion or the center portion of the wire may be 220 / mm or more, 250 / mm or more, or 280 / mm or more.
  • the large-angle grain boundary density in the surface layer portion or the center portion of the wire may be 400 / mm or less, 380 / mm or less, or 350 / mm or less.
  • ⁇ Tissue area ratio> The cross-section of the wire (that is, the cross section perpendicular to the length of the wire) is mirror-polished, then corroded with picral, and the surface layer portion is magnified 2000 times using a field emission scanning electron microscope (FE-SEM). 10 places are observed at arbitrary positions in the center, and photographs are taken.
  • the area per field of view is 2.7 ⁇ 10 ⁇ 3 mm 2 (vertical 0.045 mm, horizontal 0.060 mm).
  • a transparent sheet for example, an OHP (Over Head Projector) sheet
  • OHP Over Head Projector
  • the area ratio of the “colored region” in each transparent sheet is obtained by image analysis software, and the average value is calculated as the average value of the area ratio of the ferrite structure. In this way, the ferrite area ratio can be obtained.
  • another transparent sheet is colored in “a region overlapping with a structure other than the pearlite structure and other than the ferrite structure”, and the area ratio is obtained.
  • the area ratio of the non-pearlite and non-ferrite structure can be obtained by the above method.
  • the area ratio of the structure in the cross section of the wire is the same as the volume ratio of the structure of the wire.
  • the area ratio of the pearlite structure can be calculated by subtracting the sum of the ferrite area ratio and the non-pearlite and non-ferrite area ratio from 100 area%.
  • the cross section of the wire (that is, the cut surface perpendicular to the length direction) is mirror-polished, then polished with colloidal silica, and the surface of the wire (at the magnification of 400 times using a field emission scanning electron microscope (FE-SEM)) 4 fields of view are observed at the center and at a depth of 150 to 400 ⁇ m from the surface, and EBSD measurement (measurement by electron beam backscatter diffraction method) is performed.
  • the area per field of view is 0.0324 mm 2 (vertical 0.18 mm, horizontal 0.18 mm), and the measurement step is 0.3 ⁇ m.
  • the total length of the lines having subgrain boundaries of 2 ° or more and less than 15 ° and the total length of lines having large-angle grain boundaries of 15 ° or more are measured for the obtained results in each measurement field.
  • OIM analysis OIM: Orientation Imaging Microscopy
  • the value obtained by dividing the total line length of the large-angle grain boundary obtained in each measurement field by the area of each measurement field is the large angle in each measurement field. It is defined as the grain boundary density ⁇ 2.
  • the average value of the analysis results of the surface layer portion and the central portion is the subgrain boundary density ⁇ 1 of the ferrite crystal orientation angle difference of 2 ° or more and less than 15 ° in the pearlite structure of the surface layer portion and the central portion, and the surface layer portion and the central portion.
  • the large-angle grain boundary density ⁇ 2 at which the angle difference of the ferrite crystal orientation in the entire structure is 15 ° or more.
  • the result CI (confidence index) uses a result of 0.60 or more, and those with a CI of 0.10 or less are removed as noise. In addition, removal of CI below 0.10 is possible within OIM analysis.
  • the values of the sub-boundary density ⁇ 1 and the large-angle grain boundary density ⁇ 2 are not only in the above-described range in the surface portion of the wire (in the range of depth of 150 to 400 ⁇ m from the surface), but also in the center of the wire. It must be in range. Even when the subgrain boundary density ⁇ 1 in the central portion of the wire is in the range of 70 / mm to 600 / mm and the large angle grain boundary density ⁇ 2 is in the range of 200 / mm or more, the surface layer portion is not in the above range, or Even if it is within the range, if the central portion is not within the above range, the desired characteristics as a wire cannot be obtained. If it can be confirmed that ⁇ 1 and ⁇ 2 of the wire surface layer portion and ⁇ 1 and ⁇ 2 of the wire center portion are within the above range, it can be recognized that ⁇ 1 and ⁇ 2 are within the above range for the entire wire.
  • (D) Manufacturing Method In the manufacturing method of the wire according to the present embodiment, various conditions during pearlite transformation are optimized and the structure is controlled in order to improve the torsional characteristics of the wire.
  • the wire satisfying the above requirements of the wire according to the present embodiment can obtain the effects of the wire according to the present embodiment regardless of the manufacturing method.
  • the wire according to the present embodiment can be obtained. What is necessary is just to manufacture a wire.
  • the following manufacturing process is an example, and even when the wire composition whose chemical composition and other requirements are within the range of the wire material according to the present embodiment is obtained by a process other than the following, the wire material is included in the present invention. Needless to say, it is included.
  • a steel piece is manufactured by continuous casting and hot rolling is performed.
  • the steel slab is heated to 1000 to 1250 ° C., and the finishing temperature is 900 to 1000 ° C. and hot-rolled to ⁇ 5.5 to 7.0 mm.
  • the heating temperature of the steel slab before hot rolling is 1000 ° C. or more and 1250 ° C. or less. This is because when the heating temperature of the steel slab is less than 1000 ° C., the reaction force during hot rolling increases, and when the heating temperature of the steel slab exceeds 1250 ° C., decarburization proceeds.
  • the finish rolling temperature of hot rolling is 900 ° C. or higher.
  • finish rolling temperature is less than 900 ° C.
  • reaction force of the finish rolling increases and the shape accuracy deteriorates.
  • finish rolling temperature shall be 1000 degrees C or less. This is because, when hot rolling is performed at a temperature higher than 1000 ° C., the austenite grain size increases and the large-angle grain boundary density after pearlite transformation decreases.
  • the following four stages of cooling are performed to adjust the ferrite area ratio, subgrain boundary density, and large angle grain boundary density.
  • the purpose is to suppress austenite grain growth and generate a fine austenite structure by cooling at a high cooling rate.
  • the purpose of secondary cooling is to reduce the temperature in order to reduce the temperature difference between the wire surface layer part and the central part during the primary cooling, and to make the temperature uniform from the wire surface layer part to the central part.
  • the purpose of the tertiary cooling is to cool the target pearlite transformation temperature to a target pearlite transformation temperature at a cooling rate capable of cooling as uniformly as possible from the surface portion of the wire rod to the center portion and suppressing the ferrite transformation.
  • the pearlite transformation is carried out so that the sub-grain boundary density and the large-angle grain boundary density are within the target ranges by performing cooling to make the pearlite transformation as uniform as possible from the surface of the wire to the center.
  • the average cooling rate of primary to quaternary cooling described below is the amount of decrease in wire temperature from the start to the end of primary to quaternary cooling, expressed as the time from the start to the end of primary to quaternary cooling. Divided value.
  • the ultimate temperature of primary to quaternary cooling is the temperature of the wire at the end of primary to quaternary cooling.
  • primary cooling is performed by water cooling to 830 to 870 ° C. within an average cooling rate of 50 to 200 ° C./second.
  • finish of primary cooling are the start and completion
  • the upper limit of the average cooling rate in the primary cooling is set to 200 ° C./second or less. If the ultimate temperature in primary cooling is less than 830 ° C., ferrite transformation may proceed in a large amount only in the surface layer portion, and the ferrite area ratio in the surface layer portion increases, making it difficult to control to 45% or less. Therefore, the ultimate temperature in primary cooling is set to 830 ° C. or higher. When cooling is stopped at a temperature exceeding 870 ° C., austenite grains grow large and the large-angle grain boundary density after pearlite transformation decreases. Therefore, the ultimate temperature in the primary cooling is set to 870 ° C. or less.
  • secondary cooling is performed by air cooling in the atmosphere at an average cooling rate of less than 5 ° C./second to a range of 790 ° C. or more and 820 ° C. or less.
  • start time of the secondary cooling is equal to the end time of the refrigerant blowing in the primary cooling
  • end time of the secondary cooling is equal to the start time of the refrigerant blowing in the tertiary cooling.
  • the secondary cooling is cooling for reducing the temperature difference between the surface layer portion and the center portion of the wire that occurs during the primary cooling, and making the pearlite transformation temperature from the wire surface layer portion to the center portion uniform.
  • the average cooling rate in the secondary cooling is less than 5 ° C./second. If the ultimate temperature of the secondary cooling is less than 790 ° C., ferrite transformation may occur and the ferrite area ratio may be improved. Therefore, the ultimate temperature of the secondary cooling is 790 ° C. or higher.
  • the ultimate temperature for secondary cooling is set to 820 ° C. or lower.
  • the secondary cooling time elapsed time between the start and end of the secondary cooling
  • the secondary cooling time is preferably 5 seconds or more and 12 seconds or less. This is because when a secondary cooling time of more than 12 seconds is applied, grain growth of austenite grains is promoted.
  • a temperature difference in the wire may remain.
  • tertiary cooling is performed by blast cooling to an average cooling rate of more than 20 ° C./second and not more than 30 ° C./second to a range of 600 ° C. to 620 ° C.
  • the start and end of the tertiary cooling are the start and end of air blowing.
  • cooling is performed to a pearlite transformation temperature at which optimum subgrain boundary density and large angle grain boundary density can be obtained at a cooling rate capable of suppressing ferrite transformation. If the average cooling rate of the tertiary cooling is 20 ° C./second or less, ferrite transformation occurs and the ferrite area ratio becomes excessive. Therefore, the average cooling rate is over 20 ° C./second.
  • an average cooling rate shall be 30 degrees C / sec or less.
  • the ultimate temperature in the tertiary cooling is 600 ° C. or higher.
  • the ultimate temperature of the tertiary cooling exceeds 620 ° C.
  • the pearlite transformation temperature becomes high
  • the large-angle grain boundary density and the sub-grain boundary density are lowered
  • the tensile strength after the pearlite transformation is also lowered. Therefore, the ultimate temperature of the tertiary cooling is set to 620 ° C. or less.
  • quaternary cooling is performed to 550 ° C. or less at an average cooling rate of 10 ° C./second or less by air cooling with air.
  • the time point of starting the fourth cooling is equal to the time point of ending the air blowing in the third cooling.
  • the end of the fourth cooling is the time when the air cooling is stopped, that is, the time when reheating or blowing of the refrigerant is started on the wire.
  • the time when the temperature of the wire reaches 550 ° C. is regarded as the end of the fourth cooling.
  • the purpose of quaternary cooling is to obtain a wire having uniform large-angle grain boundary density and sub-grain boundary density from the surface layer to the center by reducing the temperature difference in the cross section of the wire during pearlite transformation.
  • the average cooling rate in the quaternary cooling is more than 10 ° C./second, the temperature change of the surface layer is large, and the subgrain boundary density decreases. Therefore, the average cooling rate in the fourth cooling is set to 10 ° C./second or less.
  • the lower limit of the average cooling rate in the quaternary cooling is not limited, but the cooling rate when the wire is allowed to cool is usually 2 ° C./second or more. Therefore, 2 ° C./second may be set as the lower limit of the average cooling rate in the fourth cooling.
  • the ultimate temperature of the fourth cooling exceeds 550 ° C., the pearlite transformation may not be completed. Therefore, the ultimate temperature of the fourth cooling is 550 ° C. or less. Since the influence of the cooling rate in the temperature range of 550 ° C. or less on the tissue is slight, accelerated cooling such as water cooling may be performed after the fourth cooling is performed to a temperature of 550 ° C. or less. In the examples to be described later, the present invention example is cooled to room temperature by cooling to 550 ° C. or lower by quaternary cooling, but the same applies even when cooled by other cooling means after completion of quaternary cooling. An organization is formed.
  • the wire rod according to the present embodiment is replaced with at least one or two selected from the group consisting of Al, Cr, V, Ti, Nb, B, Ca, and Mg as necessary instead of a part of the remaining Fe. You may contain the above element. However, since the wire according to the present embodiment can solve the problem without including these optional elements, the lower limit value of these optional elements is 0%. Hereinafter, the effect of the optional elements Al, Cr, V, Ti, Nb, B, Ca, Mg and the reason for limiting the content will be described. % For optional ingredients is% by weight.
  • Al 0 to 0.050% Al may not be contained in the wire of this embodiment.
  • Al is an element that precipitates as AlN and can increase the large-angle grain boundary density with an angle difference of 15 ° or more of the ferrite crystal orientation. In order to obtain the effect with certainty, it is preferable to contain 0.010% or more of Al.
  • Al is an element that easily forms hard oxide inclusions, when the Al content of the wire exceeds 0.050%, coarse oxide inclusions are remarkably easily formed. The deterioration of torsional characteristics becomes remarkable. Therefore, the upper limit of the Al content of the wire is 0.050%.
  • the upper limit with preferable Al content is 0.040% or less, A more preferable upper limit is 0.035% or less, Furthermore, a preferable upper limit is 0.030% or less.
  • Cr 0 to 1.00% Cr may not be contained in the wire rod according to the present embodiment.
  • Cr like Mn, is an element that increases the hardenability of the steel and increases the strength of the steel. In order to reliably obtain this effect, it is preferable to contain 0.05% or more of Cr. On the other hand, when the Cr content exceeds 1.00%, the torsional characteristics deteriorate. Therefore, the Cr content is 1.00% or less. In addition, when raising the hardenability of steel, it is preferable to contain Cr 0.10% or more, and it is still more preferable to contain 0.30% or more.
  • the upper limit of Cr is preferably 0.90% or less, and more preferably 0.80% or less.
  • V 0 to 0.15%
  • V may not be contained in the wire rod of this embodiment.
  • V combines with N and C to form carbides, nitrides or carbonitrides, and has the effect of refining austenite grains during hot rolling due to their pinning effect, improving the torsional properties of steel There is.
  • the V content is preferably 0.02% or more, and more preferably 0.03% or more.
  • the content of V exceeds 0.15%, not only the effect is saturated, but also the steel manufacturability such as cracking in the steel slab in the step of rolling the steel ingot or slab into the steel slab.
  • V content is set to 0.15% or less.
  • the V content is preferably 0.10% or less, and more preferably 0.07% or less.
  • Ti may not be contained in the wire rod of the present embodiment.
  • Ti combines with N and C to form carbides, nitrides or carbonitrides, and has the effect of refining austenite grains during hot rolling due to their pinning effect, improving the torsional properties of steel There is.
  • Ti is preferably contained in an amount of 0.002% or more.
  • the Ti content is preferably 0.005% or more, and more preferably 0.010% or more.
  • the Ti content exceeds 0.050%, not only the effect is saturated, but also the steel manufacturability such as cracking in the steel slab in the step of rolling the steel ingot or slab into the steel slab. Adversely affect. Therefore, the Ti content is 0.050% or less.
  • the Ti content is more preferably 0.025% or less.
  • Nb 0 to 0.050% Nb may not be contained in the wire rod of this embodiment.
  • Nb combines with N and C to form carbides, nitrides or carbonitrides, and has the effect of refining austenite grains during hot rolling due to their pinning effect, improving the torsional properties of steel There is.
  • Nb is preferably contained in an amount of 0.002% or more. From the viewpoint of improving torsional characteristics, the Nb content is more preferably 0.003% or more, and even more preferably 0.004% or more.
  • Nb content exceeds 0.050%, not only the effect is saturated, but also the steel productivity such as cracking in the steel slab in the step of rolling the steel ingot or slab into the steel slab.
  • Nb content is 0.050% or less.
  • the Nb content is more preferably 0.030% or less.
  • B 0 to 0.0040% B may not be contained in the wire rod of this embodiment.
  • B When B is contained in a small amount, there is an effect of reducing the ferrite structure of the steel. When it is desired to obtain the effect with certainty, it is preferable to contain 0.0001% or more of B. Even if more than 0.0040% of B is contained, not only the effect is saturated, but also a coarse nitride is generated, and the torsional characteristics are deteriorated. Therefore, if B is included, the B content is 0.0040% or less. In order to increase the area ratio of the pearlite structure, the B content is preferably 0.0004% or more, and more preferably 0.0007% or more. The content of B for improving torsional characteristics is preferably 0.0035% or less, and more preferably 0.0030% or less.
  • Ca 0 to 0.0050% Ca may not be contained in the wire rod of the present embodiment.
  • Ca has the effect of dissolving in MnS and finely dispersing MnS. By finely dispersing MnS, disconnection during wire drawing due to MnS can be suppressed.
  • Ca is preferably contained in an amount of 0.0002% or more. In order to obtain a higher effect, 0.0005% or more of Ca may be contained.
  • the Ca content exceeds 0.0050%, the effect is saturated.
  • the Ca content exceeds 0.0050%, the oxide produced by reaction with oxygen in the steel becomes coarse, which leads to a reduction in wire drawing workability. Therefore, the appropriate Ca content when contained is 0.0050% or less.
  • the Ca content is preferably 0.0030% or less, and more preferably 0.0025% or less.
  • Mg 0 to 0.0040% Mg does not need to be contained in the wire rod of this embodiment.
  • Mg is a deoxidizing element and generates an oxide. However, it also has an effect of finely dispersing MnS because it is an element having a correlation with MnS by generating sulfide. This effect can suppress disconnection during wire drawing due to MnS.
  • Mg is preferably contained in an amount of 0.0002% or more. In order to obtain a higher effect, 0.0005% or more of Mg may be contained. However, when the Mg content exceeds 0.0040%, the effect is saturated and a large amount of MgS is generated, which leads to a decrease in wire drawing workability. Therefore, when Mg is contained, the appropriate Mg content is 0.0040% or less.
  • the Mg content is preferably 0.0035% or less, and more preferably 0.0030% or less.
  • the balance of the chemical composition includes “Fe and impurities”. “Impurity” refers to what is mixed into steel materials from ores, scraps, or production environments as raw materials when industrially producing steel materials.
  • the diameter of the wire according to the present embodiment is not particularly limited, but the diameter of the wire currently distributed in the market is usually 3.5 to 7.0 mm, so this is the diameter of the wire according to the present embodiment.
  • the upper and lower limit values may be used.
  • the diameter of the wire is 3.5 mm or more, it is preferable because the burden of hot rolling at the time of manufacturing the wire can be reduced.
  • the diameter of the wire is 7.0 mm or less, it is preferable because the amount of wire drawing strain during wire drawing of the wire can be suppressed.
  • the steel wire according to another aspect of the present invention is obtained by drawing a wire according to the present embodiment.
  • the diameter of the steel wire is usually 0.5 to 1.5 mm in consideration of the application. Since the steel wire according to the present embodiment is the raw material, the chemical composition of the wire according to the present embodiment, the structure of the metal structure, the sub-boundary density ⁇ 1, and the large-angle grain boundary density ⁇ 2 are within the above-described ranges. Has excellent tensile strength and torsional properties.
  • the steel wire regarding this embodiment is manufactured through a wire drawing process with a very large amount of strain, its metal structure has undergone significant deformation.
  • the phase surrounded by the grain boundary is crushed remarkably, and the kind cannot be distinguished.
  • a method for manufacturing a steel wire according to another aspect of the present invention includes a step of drawing a wire according to the present embodiment.
  • the wire drawing is performed with a surface reduction rate such that the diameter of the steel wire finally obtained is 0.5 to 1.5 mm. Since the chemical composition of the wire according to the present embodiment, the structure of the metal structure, the subgrain boundary density ⁇ 1, and the large angle grain boundary density ⁇ 2 are within the above-described ranges, the production of the steel wire according to the present embodiment using this is used.
  • the method can suppress the number of breaks to an extremely low level, and can obtain a steel wire having excellent tensile strength and torsional characteristics.
  • the adjustment cooling after finish rolling was performed under the conditions shown in (A1) to (A21) shown in Tables 3-1 to 3-3. Specifically, with regard to (A1) to (A7), after cooling to 830 to 870 ° C. (primary cooling) within a range of an average cooling rate of 50 to 200 ° C./second by water cooling, air cooling by air is then performed. Was air-cooled (secondary cooling) to a range of 790 ° C. or higher and 820 ° C. or lower at an average cooling rate of less than 5 ° C./second. Thereafter, it is cooled to 20 ° C./second to 30 ° C./second to 600 to 620 ° C. (third cooling), is cooled to 550 ° C.
  • hot rolled wire rods were prepared from steels a to z having chemical compositions shown in Table 2 by the same method as (A1) in Table 3-1. Thereafter, dry wire drawing, plating, and wet wire drawing were performed to obtain a steel wire having a wire diameter of 0.5 mm. Values underlined in Table 2 are outside the desirable range of the present invention.
  • the pearlite area ratio of each wire is a value obtained by dividing the ferrite area ratio and the non-pearlite and non-ferrite area ratio from 100%.
  • Tables 4-1 to 4-3 and Tables 5-1 to 5-3 are values that are outside the scope of the present invention.
  • Values underlined in Table 4-3 and Table 5-3 are values that do not satisfy the acceptance criteria of the present invention.
  • Subgrain boundary density ⁇ 1 and large angle grain boundary density ⁇ 2 of the wire The cross section of the wire rod is mirror-polished, then polished with colloidal silica, and observed at four magnifications at the wire surface layer portion and the center portion using a FE-SEM at a magnification of 400 times, and EBSD measurement manufactured by TSL (Tex SEM Laboratories) Analysis was performed using the apparatus. The measurement area was 180 ⁇ 180 ⁇ m 2 and the step was 0.3 ⁇ m.
  • the total length of the sub-boundary line having an angle difference of 2 ° or more and less than 15 ° using the OIM analysis and the total length of the line of the large-angle grain boundary having an angle difference of 15 ° or more are used. Each was measured. Dividing the total length of sub-boundary lines having an angle difference of 2 ° or more and less than 15 ° by the average value of pearlite area ratio, the sub-boundary density is obtained, and the line of large-angle boundaries having an angle difference of 15 ° or more was divided by the area of one field of view to determine the large-angle grain boundary density.
  • the steel wire used for the wire which is a reinforcing material for automobile tires, preferably has a tensile strength of 2800 MPa or more
  • the tensile strength of 2800 MPa or more was evaluated as an acceptable product.
  • no pass / fail criterion was provided.
  • Torsional characteristics of steel wire after wire drawing In the torsion test, a steel wire 100 times as long as the wire diameter (diameter) was twisted until it was broken at 15 rpm, whether or not delamination occurred was judged by a torque (resistance force against torsion) curve, and the number of twists was measured. . The determination on the torque curve was performed by a method of determining that delamination occurred when the torque suddenly decreased before the disconnection. The torsion test was performed for 10 steel wires, and no delamination occurred. When the average number of twists of 10 steel wires was 23 times or more, it was evaluated that the torsional characteristics were good. .
  • the samples A1 to A7 which are examples of the present invention, all satisfy the requirements of the present invention, and the steel production conditions are appropriate. Therefore, the strength after wire drawing is 2800 MPa or more. In addition, the number of twists was 23 or more and no delamination occurred, and the wire was free from problems.
  • the average cooling rate in the primary cooling was low, and the austenite grain size was coarsened, so that ⁇ 2 was lowered, disconnection occurred during wire drawing, and wire drawing workability was poor.
  • the sample of A9 since the temperature reached in the primary cooling was low, the ferrite area ratio increased in the surface layer and the number of twists decreased.
  • the sample of A10 the ultimate temperature in the primary cooling was high and the austenite grain size was coarsened, so that ⁇ 2 was lowered and disconnection occurred.
  • the time for secondary cooling was long, and since the austenite grain size was coarsened, ⁇ 2 was lowered and disconnection occurred.
  • the ultimate temperature in the third cooling was low and ⁇ 1 was too high, so the torsional characteristics were poor.
  • the average cooling rate in the fourth cooling was high, ⁇ 1 in the surface layer portion of the wire decreased, delamination occurred during the torsion test, and the torsional characteristics were poor.
  • the sample of A17 was obtained under the manufacturing conditions in which air cooling is stopped and blast cooling is started when the wire temperature reaches the temperature shown in the table in the fourth cooling.
  • the ultimate temperature in the fourth cooling was high, the pearlite transformation was not completed, and the non-pearlite and non-ferrite area ratio was high, so that the wire drawing workability was lowered.
  • the samples of Test Nos. 1 to 19 and 26, which are examples of the present invention satisfy the desirable range of the present invention, and the wire production conditions are also appropriate. It has good workability, good torsional characteristics after wire drawing, and has the necessary tensile strength.
  • the C content was low, the ferrite area ratio was too large, and the steel wire was insufficient in strength.
  • the sample of Test No. 21 had a high C content, and the steel was hardened excessively, so that the wire drawing workability was lowered and wire breakage occurred during the wire drawing.
  • the sample of test number 22 had low ⁇ 1 due to the low Si content, and delamination occurred during the torsion test.
  • the Mn content was too high, and there were many non-ferrite and non-pearlite structures.
  • the sample of test number 24 had a low Si content, low ⁇ 1, and delamination occurred during the torsion test.
  • the sample of test number 25 had a low Mn content, a low ⁇ 1, and delamination occurred during the torsion test.
  • C, Si, Mn, N, P, and S are wires defined in the desirable ranges described above, the main structure is pearlite, the ferrite structure is 45% or less, and the non-ferrite And the non-pearlite structure is 5% or less, and the subgrain boundary density ⁇ 1 at which the difference in crystal orientation of the lamellar ferrite in the pearlite structure is 2 ° or more and less than 15 ° is 70 / mm ⁇ ⁇ 1 ⁇ 600 / mm, If the wire satisfying that the large-angle grain boundary density ⁇ 2 at which the angle difference of the ferrite crystal orientation at 15 ° or more is 200 / mm or more is obtained, a high tensile strength is obtained after the wire drawing, and the wire drawing is performed.
  • the present invention provides a wire rod for wire drawing capable of stably producing a steel wire having high strength suitable as a material such as a wire and further having excellent torsional characteristics while suppressing disconnection during wire drawing. I was able to.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Heat Treatment Of Steel (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)

Abstract

La présente invention concerne un fil qui, selon un mode de réalisation, est configuré de telle sorte que : le fil a une composition chimique au sein d'une plage prescrite ; tant dans une partie de couche de surface que dans une partie centrale, la structure principale est une structure perlitique ; le rapport de surface spécifique d'une structure ferritique est de 45 % ou moins, et le rapport de surface spécifique d'une structure non perlitique et non ferritique est de 5 % ou moins ; la densité de sous-limite ρ1 lorsque la différence angulaire d'orientation de cristal pour la ferrite lamellaire au sein de la structure perlitique est supérieure ou égale à 2° et inférieure à 15° est de 70/mm ≤ ρ1 ≤ 600/mm, et la densité ρ2 de limites à angle élevé où la différence angulaire d'orientation de cristal de ferrite au sein de la structure entière est de 15° ou plus est de 200/mm ou plus.
PCT/JP2018/019306 2017-05-18 2018-05-18 Fil, fil d'acier et procédé de fabrication d'un fil d'acier WO2018212327A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2018566321A JP6528920B2 (ja) 2017-05-18 2018-05-18 線材、及び鋼線の製造方法
CN201880032132.9A CN110621799B (zh) 2017-05-18 2018-05-18 线材、钢线以及钢线的制造方法
KR1020197034857A KR102303599B1 (ko) 2017-05-18 2018-05-18 선재, 강선, 및 강선의 제조 방법
MYPI2019006718A MY196779A (en) 2017-05-18 2018-05-18 Wire rod, drawn steel wire, and method for manufacturing drawn steel wire

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2017099227 2017-05-18
JP2017-099227 2017-05-18

Publications (1)

Publication Number Publication Date
WO2018212327A1 true WO2018212327A1 (fr) 2018-11-22

Family

ID=64273977

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2018/019306 WO2018212327A1 (fr) 2017-05-18 2018-05-18 Fil, fil d'acier et procédé de fabrication d'un fil d'acier

Country Status (6)

Country Link
JP (1) JP6528920B2 (fr)
KR (1) KR102303599B1 (fr)
CN (1) CN110621799B (fr)
MY (1) MY196779A (fr)
TW (1) TWI664296B (fr)
WO (1) WO2018212327A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021111908A1 (fr) * 2019-12-02 2021-06-10 日鉄マイクロメタル株式会社 Fil de connexion de cuivre de dispositif à semi-conducteur et dispositif à semi-conducteur

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112195391A (zh) * 2020-09-17 2021-01-08 武汉钢铁有限公司 大跨度低弧垂铝包线用高碳高硅钢丝盘条的生产方法
TWI741884B (zh) * 2020-11-24 2021-10-01 中國鋼鐵股份有限公司 雙相鋼線材及其製造方法
KR102497429B1 (ko) * 2020-12-18 2023-02-10 주식회사 포스코 절삭성 및 연자성이 우수한 흑연화 열처리용 선재 및 흑연강
KR102497435B1 (ko) * 2020-12-18 2023-02-08 주식회사 포스코 흑연화 열처리용 선재 및 흑연강
CN113684423B (zh) * 2021-10-26 2022-01-28 江苏省沙钢钢铁研究院有限公司 一种高碳钢盘条
CN115161558B (zh) * 2022-07-12 2024-04-16 鞍钢股份有限公司 一种超高强度钢丝帘线用盘条、钢丝、帘线及制造方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11315349A (ja) * 1998-04-30 1999-11-16 Kobe Steel Ltd 耐遅れ破壊性に優れた高強度線材およびその製造方法並びに高強度ボルト
JP2006241528A (ja) * 2005-03-03 2006-09-14 Kobe Steel Ltd 冷間加工性と品質安定性に優れた高強度ばね用鋼
JP2007297674A (ja) * 2006-04-28 2007-11-15 Kobe Steel Ltd 耐カッピー断線性に優れた高炭素鋼線材
WO2012132821A1 (fr) * 2011-03-31 2012-10-04 株式会社神戸製鋼所 Fil d'acier à ressort présentant une excellente aptitude à l'étirage de fil et d'excellentes caractéristiques de fatigue après étirage de fil, et fil d'acier à ressort présentant d'excellentes caractéristiques de fatigue et une excellente aptitude au formage de ressort
WO2016088803A1 (fr) * 2014-12-05 2016-06-09 新日鐵住金株式会社 Fil machine en acier à haute teneur en carbone présentant d'excellentes propriétés de tréfilage

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58141334A (ja) * 1982-02-12 1983-08-22 Nippon Steel Corp ６０Ｋｇｆ／ｍｍ↑２以上の引張強さを有し加工性、溶接性の優れた熱延鋼板の製造法
US6758919B2 (en) * 1998-01-23 2004-07-06 Columbus Steel Castings Co. Cast steel composition for railway components
JP3409055B2 (ja) 1998-10-16 2003-05-19 浦項綜合製鐵株式会社 伸線加工性が優れた高強度鋼線用線材及び高強度鋼線の製造方法
CN1307319C (zh) * 2002-10-18 2007-03-28 杰富意钢铁株式会社 滚轧成形性、耐淬裂性及扭转特性优异的机械结构用钢材以及传动轴
JP5162875B2 (ja) * 2005-10-12 2013-03-13 新日鐵住金株式会社 伸線特性に優れた高強度線材およびその製造方法
JP4310359B2 (ja) * 2006-10-31 2009-08-05 株式会社神戸製鋼所 疲労特性と伸線性に優れた硬引きばね用鋼線
EP2062991A4 (fr) * 2007-01-31 2013-01-16 Nippon Steel Corp Fil d'acier plaqué pour pws présentant une excellente propriété de torsion et son procédé de fabrication
TWI412608B (zh) * 2009-06-22 2013-10-21 Nippon Steel & Sumitomo Metal Corp 高強度極細鋼線及其製造方法
WO2011089782A1 (fr) * 2010-01-25 2011-07-28 新日本製鐵株式会社 Matériau de fil métallique, fil d'acier et procédé de fabrication du matériau de fil métallique
CN102301024B (zh) * 2010-02-01 2014-03-05 新日铁住金株式会社 线材、钢丝以及它们的制造方法
WO2011125447A1 (fr) * 2010-04-01 2011-10-13 株式会社神戸製鋼所 Fil en acier à haute teneur en carbone présentant une excellente capacité de tréfilage et une excellente propriété de fatigue après le tréfilage
JP5521885B2 (ja) * 2010-08-17 2014-06-18 新日鐵住金株式会社 高強度かつ耐水素脆化特性に優れた機械部品用鋼線、および機械部品とその製造方法
CN102644029A (zh) * 2012-05-14 2012-08-22 武汉科技大学 一种具有大应变拉拔性能的微合金化帘线钢盘条
JP5945196B2 (ja) 2012-09-11 2016-07-05 株式会社神戸製鋼所 高強度鋼線用線材
CN106460110B (zh) * 2014-04-24 2019-01-01 新日铁住金株式会社 高强度钢帘线用线材
JP2016020537A (ja) * 2014-06-16 2016-02-04 株式会社神戸製鋼所 冷間加工用機械構造用鋼及びその製造方法
JP2016014168A (ja) * 2014-07-01 2016-01-28 株式会社神戸製鋼所 鋼線用線材および鋼線
EP3181713B1 (fr) * 2014-08-15 2019-05-01 Nippon Steel & Sumitomo Metal Corporation Fil d'acier pour tréfilage

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11315349A (ja) * 1998-04-30 1999-11-16 Kobe Steel Ltd 耐遅れ破壊性に優れた高強度線材およびその製造方法並びに高強度ボルト
JP2006241528A (ja) * 2005-03-03 2006-09-14 Kobe Steel Ltd 冷間加工性と品質安定性に優れた高強度ばね用鋼
JP2007297674A (ja) * 2006-04-28 2007-11-15 Kobe Steel Ltd 耐カッピー断線性に優れた高炭素鋼線材
WO2012132821A1 (fr) * 2011-03-31 2012-10-04 株式会社神戸製鋼所 Fil d'acier à ressort présentant une excellente aptitude à l'étirage de fil et d'excellentes caractéristiques de fatigue après étirage de fil, et fil d'acier à ressort présentant d'excellentes caractéristiques de fatigue et une excellente aptitude au formage de ressort
WO2016088803A1 (fr) * 2014-12-05 2016-06-09 新日鐵住金株式会社 Fil machine en acier à haute teneur en carbone présentant d'excellentes propriétés de tréfilage

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021111908A1 (fr) * 2019-12-02 2021-06-10 日鉄マイクロメタル株式会社 Fil de connexion de cuivre de dispositif à semi-conducteur et dispositif à semi-conducteur
CN114761591A (zh) * 2019-12-02 2022-07-15 日铁新材料股份有限公司 半导体装置用铜接合线及半导体装置
CN114761591B (zh) * 2019-12-02 2024-01-05 日铁新材料股份有限公司 半导体装置用铜接合线及半导体装置

Also Published As

Publication number Publication date
MY196779A (en) 2023-05-03
CN110621799B (zh) 2021-08-31
KR102303599B1 (ko) 2021-09-23
JPWO2018212327A1 (ja) 2019-06-27
TW201900888A (zh) 2019-01-01
CN110621799A (zh) 2019-12-27
JP6528920B2 (ja) 2019-06-12
TWI664296B (zh) 2019-07-01
KR20200003012A (ko) 2020-01-08

Similar Documents

Publication Publication Date Title
WO2018212327A1 (fr) Fil, fil d'acier et procédé de fabrication d'un fil d'acier
JP6264462B2 (ja) 伸線加工用鋼線
JP5224009B2 (ja) 鋼線材及びその製造方法
JP5092749B2 (ja) 高延性の高炭素鋼線材
JP4943564B2 (ja) ソーワイヤ用素線及びその製造方法
JP5098444B2 (ja) 高延性の直接パテンティング線材の製造方法
WO2014208492A1 (fr) Fil-machine en acier à forte teneur en carbone et procédé pour sa fabrication
JP5154694B2 (ja) 加工性に優れた高炭素鋼線材
JP6481770B2 (ja) 伸線加工用鋼線材
WO2016021556A1 (fr) Fil machine d'acier haut carbone d'excellente aptitude à l'étirage
WO2018117157A1 (fr) Fil machine
JP2018197375A (ja) 伸線加工用熱間圧延線材
JP7159785B2 (ja) ラインパイプ用鋼材
JP5945196B2 (ja) 高強度鋼線用線材
JP7063394B2 (ja) 熱間圧延線材
JP7323797B2 (ja) ラインパイプ用電縫鋼管、及び、ラインパイプ用熱延鋼板
WO2017170515A1 (fr) Fil d'acier

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2018566321

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18803229

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20197034857

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 18803229

Country of ref document: EP

Kind code of ref document: A1