WO2024069985A1 - フラックス入りワイヤ及び溶接継手の製造方法 - Google Patents

フラックス入りワイヤ及び溶接継手の製造方法 Download PDF

Info

Publication number
WO2024069985A1
WO2024069985A1 PCT/JP2022/036865 JP2022036865W WO2024069985A1 WO 2024069985 A1 WO2024069985 A1 WO 2024069985A1 JP 2022036865 W JP2022036865 W JP 2022036865W WO 2024069985 A1 WO2024069985 A1 WO 2024069985A1
Authority
WO
WIPO (PCT)
Prior art keywords
content
flux
total
cored wire
wire
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2022/036865
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
孟 松尾
孝浩 加茂
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel Corp
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 Nippon Steel Corp filed Critical Nippon Steel Corp
Priority to EP22961044.9A priority Critical patent/EP4596167A4/en
Priority to CN202280062553.2A priority patent/CN118119474A/zh
Priority to US18/579,367 priority patent/US20250083264A1/en
Priority to JP2023570047A priority patent/JP7557162B2/ja
Priority to PCT/JP2022/036865 priority patent/WO2024069985A1/ja
Priority to KR1020247003359A priority patent/KR20240046708A/ko
Priority to TW112137419A priority patent/TWI887791B/zh
Publication of WO2024069985A1 publication Critical patent/WO2024069985A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/36—Selection of non-metallic compositions, e.g. coatings or fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
    • B23K35/368—Selection of non-metallic compositions of core materials either alone or conjoint with selection of soldering or welding materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/02—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape
    • B23K35/0255—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape for use in welding
    • B23K35/0261—Rods, electrodes or wires
    • B23K35/0266—Rods, electrodes or wires flux-cored
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550°C
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550°C
    • B23K35/3053—Fe as the principal constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550°C
    • B23K35/3053—Fe as the principal constituent
    • B23K35/3066—Fe as the principal constituent with Ni as next major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24—Selection of soldering or welding materials proper
    • B23K35/30—Selection of soldering or welding materials proper with the principal constituent melting at less than 1550°C
    • B23K35/3053—Fe as the principal constituent
    • B23K35/3073—Fe as the principal constituent with Mn as next major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/36—Selection of non-metallic compositions, e.g. coatings or fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
    • B23K35/3601—Selection of non-metallic compositions, e.g. coatings or fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest with inorganic compounds as principal constituents
    • B23K35/3608—Titania or titanates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/36—Selection of non-metallic compositions, e.g. coatings or fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
    • B23K35/362—Selection of compositions of fluxes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C19/00—Alloys based on nickel or cobalt
    • C22C19/03—Alloys based on nickel or cobalt based on nickel
    • C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—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
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • 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
    • C22C38/10—Ferrous alloys, e.g. steel alloys containing cobalt
    • C22C38/105—Ferrous alloys, e.g. steel alloys containing cobalt containing Co and Ni
    • 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
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • 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
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing 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
    • C22C38/16—Ferrous alloys, e.g. steel alloys containing copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • 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
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • 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
    • C22C38/52—Ferrous alloys, e.g. steel alloys containing chromium with nickel with cobalt
    • 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
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese

Definitions

  • This disclosure relates to a method for manufacturing flux-cored wire and welded joints.
  • Ni-based low-temperature steel containing 6 to 9% Ni is used for the steel materials used in liquid hydrogen tanks, liquid carbon dioxide tanks, LNG tanks, etc., because of the need to ensure toughness at the extremely low temperature of -196°C.
  • austenitic flux-cored wires that can produce weld metals with excellent low-temperature toughness are used. These flux-cored wires are mainly designed with a Ni content of 70%.
  • Patent Document 1 describes that "the Ni content is 35 to 70%, the flux contains TiO 2 , SiO 2 and ZrO 2 in a total amount of 4.0 mass% or more with respect to the total mass of the wire, and further contains Mn oxides in an amount of 0.6 to 1.2 mass% calculated as MnO 2 , and when the contents of TiO 2 , SiO 2 , ZrO 2 and MnO 2 (converted amounts) are expressed in mass% as [TiO 2 ], [SiO 2 ], [ZrO 2 ] and [MnO 2 ], respectively, [TiO 2 ]/[ZrO 2 ] is 2.3 to 3.3, [SiO 2 ]/[ZrO 2 ] is 0.9 to 1.5, and ([TiO 2 ] + [SiO 2 ] + [ZrO 2 ])/[MnO 2 ] is 5 to 13.
  • the objective of the present invention is to provide a flux-cored wire that is inexpensive, produces a weld metal with excellent low-temperature toughness, and reduces the amount of fume generated, and a method for manufacturing a welded joint using the flux-cored wire.
  • a flux-cored wire for welding having a steel sheath and flux filled inside the steel sheath,
  • the chemical composition of the steel skin is, in mass% relative to the total mass of the steel skin, C: 0 to 0.650%, Si: 0.03 to 0.50%, Mn: 3.1 to 30.0%, P: 0 to 0.050%, S: 0 to 0.050%, Cu: 0 to 5.0%, Ni: 1.0 to 30.0%, Cr: 0 to 10.0%, Mo: 0 to 10.0%, Nb: 0 to 1.0%, V: 0 to 1.0%, Co: 0 to 1.0%, Pb: 0 to 1.0%, Sn: 0 to 1.0%, Al: 0 to 0.10%, Ti: 0 to 0.10%, B: 0 to 0.1000%, N: 0 to 0.500%, O: 0 to 0.0050%, and the balance: Fe and impurities; and the sum of the Mn content and the Ni content (Mn
  • ⁇ 2> The flux-cored wire according to ⁇ 1>, wherein in a chemical composition of the steel sheath, a mass ratio (Ni/Mn) of the Mn content to the Ni content is 0.10 or more.
  • ⁇ 3> The flux-cored wire according to ⁇ 2>, wherein the mass ratio (Ni/Mn) is 1.00 or more.
  • ⁇ 4> The flux-cored wire according to any one of ⁇ 1> to ⁇ 3>, wherein the Ti content is Ti: 0.003 to 0.10%.
  • the metal components in the chemical composition of the flux-cored wire are, in mass% with respect to the total mass of the flux-cored wire, C: 0.020 to 0.650%, Si: 0.20 to 0.80%, Mn: 1.5 to 30.0%, P: 0 to 0.050%, S: 0 to 0.050%, Cu: 0 to 10.0%, Ni: 5.0 to 30.0%, Cr: 2.0 to 10.0%, Mo: 0 to 10.0%, Nb: 0 to 5.00%, V: 0 to 5.0%, Co: 0 to 1.0%, Pb: 0 to 1.0%, Sn: 0 to 1.0%, W: 0 to 10.0%, Mg: 0 to 1.00%, Al: 0 to 3.000%, Ca: 0 to 0.100%, Ti: 0 to 3.000%, B: 0 to 0.1000%, REM: 0 to 0.100%, Bi: 0 to 0.050%, N:
  • the flux-cored wire according to ⁇ 5> wherein in a chemical composition of the flux-cored wire, a mass ratio (Ni/Mn) of the Mn content to the Ni content is 0.200 or more.
  • the flux-cored wire has, in mass% with respect to the total mass of the flux-cored wire, The total amount of Ti oxides in terms of TiO2 is 3.00 to 8.00%; The total amount of silicon oxides calculated as SiO2 is 0 to 1.00%; The total amount of Zr oxide calculated as ZrO2 is 0 to 0.80%,
  • the flux-cored wire has, in mass% with respect to the total mass of the flux-cored wire, Contains one or more fluorides selected from the group consisting of K 2 SiF 6 , K 2 ZrF 6 , NaF, Na 3 AlF 6 , CaF 2 , and MgF 2 in a total content of 0.10 to 2.00%;
  • the composition contains one or more Na-containing compounds selected from the group consisting of Na oxide, NaF, and Na 3 AlF 6 , the total of which (Na oxide is calculated as Na 2 O) is 0.01 to 2.00%,
  • the flux-cored wire according to any one of ⁇ 1> to ⁇ 7>, containing one or more K-containing compounds selected from K oxide, K 2 SiF 6 , and K 2 ZrF 6, and the total amount of the K oxide compounds (in terms of K 2 O) is 0.01 to 2.00%.
  • CaF2 , MgF2 , NaF, K2SiF6 , K2ZrF6 , and Na3AlF6 are the contents of the compounds represented by each chemical formula in mass% relative to the total mass of the flux-cored wire.
  • SiO2 represents the total of the SiO2 equivalent value of Si oxide
  • Al2O3 represents the total of the Al2O3 equivalent value of Al oxide
  • ZrO2 represents the total of the ZrO2 equivalent value of Zr oxide
  • MgO represents the total of the MgO equivalent value of Mg oxide
  • CaO represents the total of the CaO equivalent value of Ca oxide
  • Na2O represents the total of the Na2O equivalent value of Na oxide
  • K2O represents the total of the K2O equivalent value of K oxide
  • MnO2 represents the total of the MnO2 equivalent value of Mn oxide
  • FeO represents the total of the FeO equivalent value of Fe oxide.
  • the SiO2 converted value, the Al2O3 converted value, the ZrO2 converted value, the MgO converted value, the CaO converted value, the Na2O converted value, the K2O converted value, the MnO2 converted value, and the FeO converted value in Formula A are expressed in mass% with respect to the total mass of the flux-cored wire.
  • the steel sheath has a welded portion at a joint.
  • ⁇ 12> The flux-cored wire according to any one of ⁇ 1> to ⁇ 11>, wherein a surface of the flux-cored wire is coated with one or both of polytetrafluoroethylene oil and perfluoropolyether oil.
  • a method for manufacturing a welded joint comprising a step of welding steel materials using the flux-cored wire according to any one of ⁇ 1> to ⁇ 12>.
  • the present disclosure provides a flux-cored wire that is inexpensive and produces weld metal with excellent low-temperature toughness while reducing the amount of fume generated, and a method for manufacturing a welded joint using the flux-cored wire.
  • the flux-cored wire according to the present disclosure (hereinafter, may be simply referred to as "wire") comprises a steel sheath (hereinafter, may be simply referred to as "sheath”) and flux filled inside the steel sheath.
  • the flux-cored wire according to the present disclosure has a steel sheath having a predetermined chemical composition.
  • the flux-cored wire according to the present disclosure preferably has a predetermined metal component in its chemical composition, and preferably contains predetermined amounts of Ti oxide, Si oxide, fluoride, Na-containing compound, and K-containing compound, and preferably contains no Zr oxide and Al oxide or contains them in predetermined amounts.
  • the flux-cored wire according to the present disclosure is an inexpensive wire that can provide a weld metal having excellent low-temperature toughness and can reduce the amount of fume generation.
  • the flux-cored wire according to the present disclosure was discovered based on the following findings.
  • the inventors have investigated a technique for obtaining a wire that can improve the low-temperature toughness of the weld metal and reduce the amount of fume generation even when the Ni content is reduced and the Mn content is increased.
  • Fumes are metal vapors generated from the molten pool that are released into the air by the arc force and then solidify.
  • the amount of fumes generated can be reduced by controlling this arc force.
  • the arc force varies not only with the welding conditions but also with the components of the steel sheath.
  • the flux-cored wire according to the present disclosure is inexpensive, can provide a weld metal having excellent low-temperature toughness, and can reduce the amount of fume generation.
  • the inventors have also investigated oxides, Na-containing compounds, and K-containing compounds in the wire and found that controlling the amounts of these compounds further improves low temperature toughness. From the above findings, it has been found that the flux-cored wire according to the present disclosure preferably contains oxides, a Na-containing compound, and a K-containing compound in predetermined amounts, and thereby a weld metal that is inexpensive and has excellent low-temperature toughness can be obtained, and the wire can generate a reduced amount of fumes.
  • the chemical composition of the steel skin is: C: 0 to 0.650%, Si: 0.03 to 0.50%, Mn: 3.1 to 30.0%, P: 0 to 0.050%, S: 0 to 0.050%, Cu: 0 to 5.0%, Ni: 1.0 to 30.0%, Cr: 0 to 10.0%, Mo: 0 to 10.0%, Nb: 0 to 1.0%, V: 0 to 1.0%, Co: 0 to 1.0%, Pb: 0 to 1.0%, Sn: 0 to 1.0%, Al: 0 to 0.10%, Ti: 0 to 0.10%, B: 0 to 0.1000% N: 0 to 0.500%, O: 0 to 0.0050%, and the balance: Fe and impurities; and the sum of the Mn content and the Ni content (Mn+Ni) satisfies the formula: Mn+Ni ⁇ 5.0%, The total of the Mn content, the Ni content, and the Cr content (Mn+Ni+Cr) satisfies the
  • C is an element that generates spatter.
  • C is also an interstitial solid solution strengthening element. If the C content of the sheath is excessive, the sheath becomes hard, making it difficult to process the core wire. Spatter also increases. Therefore, the C content of the outer skin is set to 0 to 0.650%. However, to reduce the C content of the sheath to 0%, the cost of decarbonization increases. In addition, the C content of the wire may be insufficient, and the strength of the weld metal may be insufficient. Therefore, if the C content of the sheath is low, the C content of the flux must be increased.
  • the lower limit of the C content of the sheath may be 0.003%, 0.005%, or 0.008%.
  • the upper limit of the C content of the outer skin is preferably 0.600%, 0.500%, 0.400%, 0.300%, 0.200%, less than 0.200%, 0.190%, 0.180%, 0.150%, or 0.120%.
  • Silicon is a deoxidizing element. If the silicon content of the outer skin is too low, the phosphorus content of the outer skin increases. On the other hand, Si has a low solid solubility in the austenite phase, and the greater the Si content, the greater the amount of brittle phases such as intermetallic compounds and ⁇ ferrite that are generated at high temperatures, resulting in a deterioration in high-temperature ductility. Therefore, the Si content of the outer skin is set to 0.03 to 0.50%. The lower limit of the Si content of the outer skin is preferably 0.04%, 0.05%, or 0.08%. The upper limit of the Si content of the outer skin is preferably less than 0.50%, 0.48%, 0.45%, 0.40%, 0.35%, 0.30%, or 0.20%.
  • Mn is an element that causes an increase in the amount of fume generation. In order to reduce the amount of fume generation, the lower the Mn content of the outer sheath, the more advantageous it is. Moreover, if Mn is added in excess, the stacking fault energy decreases and the toughness deteriorates. On the other hand, Mn is an austenite stabilizing element. If the Mn content of the sheath is too low, the Mn content of the entire wire becomes insufficient, the austenitization of the weld metal becomes difficult, and the low-temperature toughness deteriorates. In addition, in order to ensure the low-temperature toughness of the weld metal, it becomes necessary to excessively increase the Mn content of the flux.
  • the Mn content of the outer skin is set to 3.1 to 30.0%.
  • the lower limit of the Mn content in the skin is preferably 5.0%, greater than 5.0%, 5.2%, greater than 6.0%, 6.2%, 7.0%, greater than 7.0%, 7.2%, greater than 10.0%, or 10.2%.
  • the upper limit of the Mn content of the outer skin is preferably 28.0%, 26.0%, 25.0%, 23.0%, 21.0%, 20.0%, 19.0%, 18.0%, 15.0%, or 12.0%.
  • the lower limit of the P content of the outer sheath is set to 0%.
  • the P content of the outer sheath is preferably 0.003% or more.
  • the adverse effect of P on the toughness is within an acceptable range.
  • the P content of the outer sheath is preferably 0.040% or less, 0.030% or less, 0.020% or less, 0.015% or less, or 0.010% or less.
  • the lower limit of the S content of the outer sheath is set to 0%.
  • the S content of the outer sheath is preferably 0.003% or more.
  • the adverse effect of S on the toughness is within an acceptable range.
  • the S content of the outer sheath is preferably 0.040% or less, 0.030% or less, 0.020% or less, 0.015% or less, or 0.010% or less.
  • Cu is a precipitation strengthening element and may be contained in the sheath to improve the strength of the weld metal.
  • the Cu content in the outer skin is set to 0 to 5.0%.
  • the lower limit of the Cu content in the outer skin is preferably 0.3%, 0.5%, or 0.7%.
  • the upper limit for the Cu content of the outer skin is preferably 4.5%, 4.0%, or 3.5%.
  • Ni is an austenite stabilizing element. If the Ni content of the sheath is too low, the Ni content of the entire wire will be insufficient, making it difficult for the weld metal to undergo austenitization, and the low-temperature toughness will deteriorate. In addition, in order to ensure the low-temperature toughness of the weld metal, it will be necessary to excessively increase the Ni content of the flux. On the other hand, increasing the Ni content of the sheath increases the cost of the wire. Therefore, the Ni content of the outer skin is set to 1.0 to 30.0%.
  • the lower limit of the Ni content in the outer skin is preferably 2.0%, 3.0%, 5.0%, more than 6.0%, 6.2%, 7.0%, more than 8.0%, or 8.2%.
  • the upper limit of the Ni content in the outer skin is preferably 28.0%, 26.0%, 24.0%, 22.0%, 20.0%, 19.0%, 18.0%, 15.0%, or 12.0%.
  • Cr is an austenite stabilizing element and may be contained in the outer sheath in order to improve the low temperature toughness of the weld metal.
  • the Cr content of the outer sheath is set to 0 to 10.0%.
  • the lower limit of the Cr content in the sheath is preferably 0.01%, 0.02%, 1.0%, 2.0%, or 3.0%.
  • the upper limit for the Cr content in the outer skin is preferably 9.0%, 8.0%, less than 8.0%, 7.8%, 7.0%, less than 6.0%, or 5.8%.
  • Mo is a precipitation strengthening element and may be contained in the sheath to improve the strength of the weld metal.
  • Mo content in the sheath is set to 0 to 10.0%.
  • the lower limit of the Mo content in the outer skin is preferably 1.0%, 2.0%, or 3.0%.
  • the upper limit of the Mo content in the outer skin is preferably 9.0%, 8.0%, or 7.0%.
  • Nb is an element that forms carbides in the weld metal and increases the strength of the weld metal, and therefore may be contained in the sheath.
  • the Nb content in the sheath is set to 0 to 1.0%.
  • the lower limit of the Nb content of the outer sheath is preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit for the Nb content of the outer sheath is preferably 0.95%, 0.9%, 0.85%, or 0.8%.
  • V (V: 0 to 1.0%) V is an element that forms carbonitrides in the weld metal and increases the strength of the weld metal, and therefore may be contained in the sheath.
  • the V content of the outer skin is set to 0 to 1.0%.
  • the lower limit of the V content of the outer skin is preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit for the V content of the outer skin is preferably 0.95%, 0.9%, 0.85%, or 0.8%.
  • Co (Co: 0 to 1.0%)
  • Co is an element that increases the strength of the weld metal through solid solution strengthening, and therefore may be contained in the outer sheath.
  • the Co content in the outer sheath is set to 0 to 1.0%.
  • the lower limit of the Co content in the outer sheath is preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit of the Co content in the outer skin is preferably 0.95%, 0.9%, 0.85%, or 0.8%.
  • Pb 0 to 1.0%
  • Pb has the effect of improving the machinability of the weld metal and may be contained in the sheath.
  • the Pb content in the sheath is set to 0 to 1.0%.
  • the lower limit of the Pb content of the outer sheath is preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit for the Pb content of the outer sheath is preferably 0.95%, 0.9%, 0.85%, or 0.8%.
  • Sn is an element that improves the corrosion resistance of the weld metal, and therefore may be contained in the sheath.
  • the Sn content of the outer sheath is set to 0 to 1.0%.
  • the lower limit of the Sn content in the sheath is preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit for the Sn content of the sheath is preferably 0.95%, 0.9%, 0.85%, or 0.8%.
  • Al is a deoxidizing element and may be contained in the sheath in order to suppress welding defects and improve the cleanliness of the weld metal.
  • the Al content of the sheath is set to 0 to 0.10%.
  • the lower limit of the Al content of the outer skin is preferably 0.01%, 0.02%, or 0.03%.
  • the upper limit of the Al content of the outer skin is preferably 0.09%, 0.08%, or 0.07%.
  • Ti is a deoxidizing element and may be contained in the outer sheath in order to suppress welding defects and improve the cleanliness of the weld metal.
  • the Ti content in the outer skin is set to 0 to 0.10%.
  • the lower limit of the Ti content in the outer skin is preferably 0.003%, 0.01%, 0.02%, or 0.03%.
  • the upper limit of the Ti content in the sheath is preferably 0.09%, 0.08%, or 0.07%.
  • B is an austenite stabilizing element and an interstitial solid solution strengthening element, and may be contained in the outer sheath in order to improve the low temperature toughness and strength of the weld metal.
  • B content of the sheath is set to 0 to 0.1000%.
  • the lower limit of the B content in the outer skin is preferably 0.0005%, 0.0010%, or 0.0020%.
  • the upper limit of the B content in the outer skin is preferably 0.0800%, 0.0500%, or 0.0100%.
  • N is an austenite stabilizing element and an interstitial solid solution strengthening element, and may be contained in the outer sheath in order to improve the low temperature toughness and strength of the weld metal.
  • the N content of the outer skin is set to 0 to 0.500%.
  • the lower limit of the N content of the outer skin is preferably 0.001%, 0.010%, or 0.050%.
  • the upper limit for the N content of the skin is preferably 0.450%, 0.400%, or 0.350%.
  • O may be contained in the sheath as an impurity.
  • the upper limit of the O content in the sheath is set to 0.0050% or less.
  • the upper limit of the O content in the outer skin is preferably 0.0040% or 0.0030%.
  • the lower limit of the O content in the outer skin is preferably 0.0003% or 0.0005%.
  • the other remaining components in the chemical composition of the exine shell are Fe and impurities.
  • impurities refers to components that are mixed in during the industrial production of the outer sheath due to raw materials such as ores or scraps, or due to various factors in the manufacturing process, and are acceptable within the range that does not adversely affect the characteristics of the wire.
  • Mn and Ni are austenite stabilizing elements that improve the low-temperature toughness of the weld metal.
  • the Mn content and Ni content in the sheath are each within the above range, and the total of the Mn content and Ni content (Mn+Ni) is set to 5.0% or more.
  • the total content of Mn and Ni in the outer skin (Mn+Ni) is preferably 7.0% or more, 10.0% or more, or 15.0% or more.
  • Mn is an element that causes an increase in the amount of fume generation. Moreover, excessive addition of Mn reduces stacking fault energy and deteriorates toughness. Therefore, from the viewpoint of reducing the amount of fume generation while suppressing the cost of wire and improving the low-temperature toughness of the weld metal, it is preferable that the Mn content and Ni content in the sheath each satisfy the above range, and the total of the Mn content and Ni content (Mn + Ni) is 37.0% or less.
  • the total content of Mn and Ni in the outer skin (Mn+Ni) is more preferably 35.0% or less, 32.0% or less, or 30.0% or less.
  • Mn, Ni, and Cr are each an austenite stabilizing element and improve the low-temperature toughness of the weld metal.
  • Ni is an expensive metal
  • the Mn content, Ni content, and Cr content in the sheath each satisfy the above-mentioned ranges, and the total content of Mn, Ni, and Cr (Mn+Ni+Cr) is set to 15.0% or more.
  • the total of the Mn content, Ni content and Cr content (Mn+Ni+Cr) in the outer skin is preferably 17.0% or more, 19.0% or more, 20.0% or more, 22.0% or more, 24.0% or more, 26.0% or more, 28.0% or more, or 30.0% or more.
  • Mn is an element that causes an increase in the amount of fume generation. Moreover, excessive addition of Mn reduces stacking fault energy and deteriorates toughness.
  • Cr is an element that forms a martensite structure, and the martensite structure formed in the sheath affects the workability of the wire. Moreover, Cr causes an increase in the amount of low-melting point compounds in the molten metal.
  • the Mn content, Ni content, and Cr content in the sheath each satisfy the above range, and the total of the Mn content, Ni content, and Cr content (Mn + Ni + Cr) is 47.0% or less.
  • the total content of Mn, Ni and Cr in the outer skin (Mn+Ni+Cr) is more preferably 45.0% or less, 42.0% or less, or 40.0% or less.
  • Mn and Ni are austenite stabilizing elements and improve the low temperature toughness of the weld metal.
  • Ni is an expensive metal
  • Mn is an element that causes an increase in the amount of fume generated.
  • Mn is added in excess, the stacking fault energy decreases, and the toughness deteriorates.
  • Ni improves the toughness by increasing the stacking fault energy. Therefore, from the viewpoint of improving the low-temperature toughness of the weld metal and reducing the amount of fume generation while suppressing the cost of the wire, the mass ratio (Ni/Mn) of the Mn content to the Ni content in the sheath is preferably 0.10 or more.
  • the lower limit of the mass ratio (Ni/Mn) of the Mn content to the Ni content in the outer skin is more preferably 0.15, 0.20, 0.30, 0.50, 0.70, 1.00, 1.10, or 1.20.
  • the upper limit of the mass ratio (Ni/Mn) of the Mn content to the Ni content in the outer skin is preferably 10.00, 8.00, or 5.00.
  • the fcc proportion in the core wire is set to 70% or more.
  • the fcc proportion is preferably 80% or more, or 90% or more, and may be 100%.
  • the remainder of the structure is bcc.
  • the fcc ratio in the structure of the core wire can be determined by the following method.
  • a sample is taken from the core wire, and the bcc ratio (%) is measured on the surface of the sample by a magnetic induction method using a FERITSCOPE (registered trademark) FMP30 (manufactured by Fisher Instruments Inc.) and a Fisher Instruments Inc. probe (FGAB 1.3-Fe) as the probe of the measuring instrument, and the arithmetic mean value of the measured bcc ratios is calculated.
  • the metal components in the preferred chemical composition of the flux-cored wire according to the present disclosure will be described below.
  • “%” means “mass % with respect to the total mass of the flux-cored wire” unless otherwise specified.
  • the metallic components of the flux-cored wire may be contained in the steel sheath or in the flux.
  • the flux-cored wire according to the present disclosure has a plating layer on the outer surface of the steel sheath, it may be included in the plating layer.
  • the "metallic components in the chemical composition" of the flux-cored wire means the components contained in the flux-cored wire excluding oxides, fluorides, nitrides, and metal carbonates. Note that the oxides, fluorides, nitrides, and metal carbonates present in the steel sheath are not contained or are contained in extremely small amounts, so they are not removed during measurement. In other words, the above “components excluding oxides, fluorides, nitrides, and metal carbonates” means excluding the oxides, fluorides, nitrides, and metal carbonates contained in the flux.
  • the metal components in the chemical composition of the flux-cored wire according to the present disclosure are: C: 0.020 to 0.650%, Si: 0.20 to 0.80%, Mn: 1.5 to 30. %, P: 0 to 0.050%, S: 0 to 0.050%, Cu: 0 to 10.0%, Ni: 5.0 to 30.0%, Cr: 2.0 to 10.0%, Mo: 0 to 10.0%, Nb: 0 to 5.00%, V: 0 to 5.0%, Co: 0 to 1.0%, Pb: 0 to 1.0%, Sn: 0 to 1.0%, W: 0 to 10.0%, Mg: 0 to 1.00%, Al: 0 to 3.000%, Ca: 0 to 0.100%, Ti: 0 to 3.000%, B: 0 to 0.1000%, REM: 0 to 0.100%, Bi: 0 to 0.050%, N: 0 to 1.000%, It is preferable that O is 0 to 0.020%, and the balance is Fe and impurities.
  • the above components are the contents of components other than oxides, fluorides, nitrides, and metal carbonates.
  • C (C: 0.020 to 0.650%) C is an element that improves the strength of the weld metal and ensures the strength of the weld metal.
  • the C content of the wire is preferably set to 0.020 to 0.650%.
  • the lower limit of the C content of the wire is more preferably 0.050%, 0.100%, or 0.200%.
  • the upper limit of the C content of the wire is more preferably 0.600%, 0.550%, 0.500%, 0.450%, 0.400%, or 0.350%.
  • Si 0.20 to 0.80%
  • Silicon improves the cleanliness of the weld metal and suppresses the occurrence of welding defects such as blowholes.
  • the Si content of the wire is preferably set to 0.20 to 0.80%.
  • the lower limit of the Si content of the wire is more preferably 0.25%, 0.30%, or 0.35%.
  • the upper limit of the Si content of the wire is more preferably 0.75%, 0.70%, or 0.65%.
  • Mn is an austenite stabilizing element. By increasing the Mn content of the wire, the austenitization of the weld metal can be promoted, and low-temperature toughness can be ensured. In addition, the Mn content added to the steel sheath does not need to be excessively increased in order to ensure the low-temperature toughness of the weld metal. Mn is an element that functions as a deoxidizer to improve the cleanliness of the weld metal. Mn also forms MnS, which renders S in the weld metal harmless and improves the low-temperature toughness of the weld metal. In addition, Mn has the effect of preventing high-temperature cracking.
  • the Mn content of the wire is preferably set to 1.5 to 30.0%.
  • the lower limit of the Mn content of the wire is more preferably 2.0%, 5.0%, 7.0%, or 9.0%.
  • the upper limit of the Mn content of the wire is more preferably 28.0%, 25.0%, 22.0%, or 20.0%.
  • the P content of the wire is preferably 0.003% or more.
  • the P content of the wire is preferably set to 0 to 0.050%.
  • the P content of the wire is more preferably 0.040% or less, 0.030% or less, 0.020% or less, 0.015% or less, or 0.010% or less.
  • the S content of the wire is preferably 0.003% or more.
  • the S content of the wire is preferably 0 to 0.050%.
  • the S content of the wire is more preferably 0.040% or less, 0.030% or less, 0.020% or less, 0.015% or less, or 0.010% or less.
  • Cu is a precipitation strengthening element and may be contained in the wire to improve the strength of the weld metal
  • Cu is an austenite stabilizing element and may be contained in the wire to improve the low temperature toughness of the weld metal.
  • the Cu content of the wire is preferably set to 0 to 10.0%.
  • the lower limit of the Cu content in the wire is more preferably 0.5%, 0.7%, or 1.0%.
  • the upper limit of the Cu content of the wire is more preferably 9.5%, 9.0%, or 8.0%.
  • Ni is an austenite stabilizing element.
  • the Ni content of the wire is preferably 5.0 to 30.0%.
  • the lower limit of the Ni content of the wire is more preferably 7.0%, 10.0%, or 12.0%.
  • the upper limit of the Ni content of the wire is more preferably 28.0%, 25.0%, 23.0%, 20.0%, 19.0%, 18.0%, or 17.0%.
  • Cr is an austenite stabilizing element.
  • the Cr content of the wire is preferably set to 2.0 to 10.0%.
  • the lower limit of the Cr content of the wire is more preferably 2.5%, 3.0%, or 3.5%.
  • the upper limit of the Cr content of the wire is more preferably 9.5%, 9.0%, or 8.0%.
  • Mo is a solid solution strengthening element and a precipitation strengthening element, and may be contained in the wire to improve the strength of the weld metal.
  • the Mo content of the wire is preferably set to 0 to 10.0%.
  • the lower limit of the Mo content of the wire is more preferably 2.0%, 2.5%, 3.0%, or 3.5%.
  • the upper limit of the Mo content of the wire is more preferably 9.8%, 9.5%, 9.0%, or 8.0%.
  • Nb is an element that forms carbides in the weld metal and increases the strength of the weld metal, and therefore may be contained in the wire.
  • the Nb content of the wire is preferably set to 0 to 5.00%.
  • the lower limit of the Nb content of the wire is more preferably 0.50%, 1.00%, or 1.50%.
  • the upper limit of the Nb content of the wire is more preferably 4.50%, 4.00%, or 3.50%.
  • V is an element that forms carbonitrides in the weld metal and increases the strength of the weld metal, and therefore may be contained in the wire.
  • the V content of the wire is preferably set to 0 to 5.0%.
  • the lower limit of the V content of the wire is more preferably 0.5%, 1.0%, or 1.5%.
  • the upper limit of the V content of the wire is more preferably 4.5%, 4.0%, or 3.5%.
  • Co (Co: 0 to 1.0%)
  • Co is an element that increases the strength of the weld metal through solid solution strengthening, and therefore may be contained in the wire.
  • the Co content of the wire is preferably set to 0 to 1.0%.
  • the lower limit of the Co content of the wire is more preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit of the Co content of the wire is more preferably 0.8%, 0.7%, 0.6%, or 0.3%.
  • Pb 0 to 1.0%
  • the Pb content of the wire is preferably set to 0 to 1.0%.
  • the lower limit of the Pb content of the wire is more preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit of the Pb content of the wire is more preferably 0.9%, 0.8%, 0.7%, 0.6%, or 0.3%.
  • Sn is an element that improves the corrosion resistance of the weld metal and may be contained in the wire.
  • the Sn content of the wire is preferably set to 0 to 1.0%.
  • the lower limit of the Sn content of the wire is more preferably 0.01%, 0.05%, 0.1%, 0.15%, or 0.2%.
  • the upper limit of the Sn content of the wire is more preferably 0.8%, 0.7%, 0.6%, or 0.3%.
  • W is a solid solution strengthening element and may be contained in the wire to improve the strength of the weld metal.
  • the W content of the wire is preferably set to 0 to 10.0%.
  • the lower limit of the W content of the wire is more preferably 0.5%, 1.0%, or 2.0%.
  • the upper limit of the W content of the wire is more preferably 9.0%, 8.0%, 7.0%, or 6.0%.
  • Mg is a deoxidizing element and is effective in reducing oxygen in the weld metal and improving the toughness of the weld metal, so may be contained in the wire.
  • the Mg content of the wire is preferably set to 0 to 1.00%.
  • the lower limit of the Mg content of the wire is more preferably 0.02%, 0.05%, 0.10%, or 0.20%.
  • the upper limit of the Mg content of the wire is more preferably 0.90%, 0.80%, or 0.70%.
  • Al is a deoxidizing element and is effective in suppressing the occurrence of welding defects such as blowholes and improving the cleanliness of the weld metal, and therefore may be contained in the wire.
  • the Al content of the wire is preferably set to 0 to 3.000%.
  • the lower limit of the Al content of the wire is more preferably 0.005%, 0.010%, 0.020%, or 0.050%.
  • the upper limit of the Al content of the wire is more preferably 2.500%, 2.000%, or 1.500%.
  • Ca (Ca: 0 to 0.100%) Ca has the effect of changing the structure of sulfides in the weld metal and of reducing the size of sulfides and oxides in the weld metal, and is therefore effective in improving the ductility and toughness of the weld metal, so Ca may be contained in the wire.
  • the Ca content of the wire is preferably 0 to 0.100%.
  • the lower limit of the Ca content in the wire is more preferably 0.010%, 0.020%, or 0.030%.
  • the upper limit of the Ca content in the wire is more preferably 0.095%, 0.090%, or 0.085%.
  • Ti is a deoxidizing element and is effective in suppressing the occurrence of welding defects such as blowholes and improving cleanliness, and therefore may be contained in the wire.
  • the Ti content of the wire is preferably set to 0 to 3.000%.
  • the lower limit of the Ti content of the wire is more preferably 0.020%, 0.050%, or 0.100%.
  • the upper limit of the Ti content of the wire is more preferably 2.500%, 2.000%, or 1.500%.
  • B has the effect of strengthening the grain boundaries of the weld metal and further increasing the tensile strength of the weld metal, and therefore may be contained in the wire.
  • the B content of the wire is preferably set to 0 to 0.1000%.
  • the lower limit of the B content of the wire is more preferably 0.0010%, 0.0020%, or 0.0030%.
  • the upper limit of the B content of the wire is more preferably 0.0900%, 0.0700%, or 0.0500%.
  • REM 0 to 0.100%
  • the REM content of the wire is preferably set to 0 to 0.100%.
  • the lower limit of the REM content of the wire is more preferably 0.001%, 0.002%, or 0.005%.
  • the upper limit of the REM content of the wire is more preferably 0.090%, 0.080%, or 0.070%.
  • REM refers to a total of 17 elements consisting of Sc, Y, and lanthanides
  • REM content refers to the total content of these 17 elements.
  • Bi is an element that improves the detachability of slag and may be contained in the wire.
  • the Bi content of the wire is preferably set to 0 to 0.050%.
  • the lower limit of the Bi content in the wire is more preferably 0.005%, 0.010%, or 0.020%.
  • the upper limit of the Bi content in the wire is more preferably 0.048%, 0.045%, 0.040%, or 0.035%.
  • N is an austenite stabilizing element and also an interstitial solid solution strengthening element. Furthermore, N is an element that has less adverse effects on the toughness of the weld metal due to the increase in the strength of the weld metal compared to C.
  • the N content of the wire By increasing the N content of the wire, the austenitization of the weld metal can be promoted, and the low temperature toughness of the weld metal can be ensured. In addition, the strength of the weld metal can be increased.
  • the N content of the wire is preferably set to 0 to 1.000%.
  • the lower limit of the N content of the wire is more preferably 0.005%, 0.007%, 0.010%, 0.015%, 0.020%, 0.030%, 0.050%, 0.070%, 0.100%, or 0.150%.
  • the upper limit of the N content of the wire is more preferably 0.950%, 0.900%, or 0.850%.
  • O may be contained as an impurity in the metal components of the wire.
  • the upper limit of the O content of the wire is set to 0.020% or less.
  • the upper limit of the O content of the wire is preferably 0.015%, 0.010%, or 0.005%.
  • the lower limit of the O content of the wire is preferably 0.0005%, 0.001%, or 0.002%.
  • the O content referred to here means the amount of oxygen contained in the metal components of the wire, for example, the amount of oxygen contained as an oxide film of the alloy powder, etc. Therefore, oxygen contained in the wire as an oxide is excluded.
  • the remaining components in the metal composition of the wire are Fe and impurities.
  • the remaining Fe is, for example, Fe contained in the steel sheath, Fe in the alloy powder contained in the flux (for example, iron powder), and the like.
  • impurities refers to components that are mixed in during industrial production of the wire, either due to the raw materials or due to various factors in the production process, and that are acceptable within a range that does not adversely affect the wire.
  • Mn and Ni are austenite stabilizing elements and improve the low temperature toughness of the weld metal.
  • Ni is an expensive metal
  • Mn is an element that causes an increase in the amount of fume generated.
  • Mn is added in excess, the stacking fault energy decreases, and the toughness deteriorates.
  • Ni improves the toughness by increasing the stacking fault energy. Therefore, from the viewpoint of improving the low-temperature toughness of the weld metal and reducing the amount of fume generation while suppressing the cost of the wire, the mass ratio of the Mn content to the Ni content (Ni/Mn) in the wire is preferably 0.200 or more.
  • the lower limit of the mass ratio (Mn/Ni) of the Mn content to the Ni content in the wire is more preferably 0.300, 0.400, 0.500, 0.600, 0.700, or 1.000.
  • the upper limit of the mass ratio (Ni/Mn) of the Mn content to the Ni content in the wire is more preferably 10.000, 8.000, or 5.000.
  • oxides, fluorides, nitrides, and metal carbonates present in the steel sheath are not contained or are contained in extremely small amounts, and therefore, in this specification, when the contents of oxides, fluorides, nitrides, and metal carbonates are mentioned, it means the contents of oxides, fluorides, nitrides, and metal carbonates contained in the flux.
  • Ti oxides increase the oxygen content in the weld metal and affect the low-temperature toughness.
  • Ti oxide is a slag component that acts to uniformly cover the entire bead with slag.
  • Ti oxide has the effect of stabilizing the duration of the arc and reducing the amount of spatter. Therefore, the inclusion of Ti oxide improves welding workability (especially vertical welding).
  • the total of Ti oxides in terms of TiO2 3.00% or more By making the total of Ti oxides in terms of TiO2 3.00% or more, slag is appropriately generated and the bead can be uniformly covered, so that the poor appearance of the bead caused by the slag being burned onto the bead surface can be suppressed.
  • the arc can be stabilized and the amount of spatter generation can be reduced.
  • welding workability especially vertical welding ability
  • the total of the Ti oxides in terms of TiO2 8.00% or less the amount of oxygen in the weld metal can be suppressed, and low-temperature toughness can be ensured.
  • the total of the Ti oxides in terms of TiO2 8.00% or less the increase in viscosity of the slag can be suppressed, so that the slag does not become too thick, and the toe of the bead can be prevented from becoming bulging. Also, by making the total of the Ti oxides in terms of TiO2 8.00% or less, the occurrence of pits can be suppressed. Also, the occurrence of slag entrapment can be suppressed.
  • the total amount of Ti oxides calculated as TiO2 is preferably 3.00 to 8.00%.
  • the lower limit of the total amount of Ti oxides calculated as TiO2 is more preferably 3.50%, 4.00%, or 4.50%.
  • the upper limit of the total amount of Ti oxides calculated as TiO2 is more preferably 7.50%, 7.00%, or 6.50%.
  • Ti oxides can exist mainly in the flux as rutile, titanium oxide, titanium slag, ilmenite, sodium titanate, potassium titanate, etc. Therefore, the Ti oxide content in the flux can be adjusted to the above range mainly by controlling the Ti oxide content.
  • the total TiO2 equivalent value of Ti oxides refers to the mass % of TiO2 relative to the total mass of the wire when all Ti oxides contained in the wire (e.g., TiO, TiO2 , Ti2O3 , Ti3O5 , etc., added as rutile, titanium oxide, titanium slag, ilmenite, sodium titanate, potassium titanate , etc.) are converted into TiO2 .
  • the total amount of Ti oxides converted to TiO2 is determined by analyzing the mass of Ti present in the wire as oxides using an X-ray fluorescence analyzer and an X-ray diffraction (XRD) device.
  • the amount of Ti present in the wire as oxides and the amount of Ti present as metal components can be determined separately by analyzing the components contained in the flux by X-ray fluorescence analysis and then analyzing the molecular structure of the components by X-ray diffraction (XRD). Specifically, first, the flux is collected from the wire and analyzed by the above method. For example, if TiO2 , Ti2O3 , and Ti3O5 are detected by the analysis, the mass percentages of each Ti oxide are expressed as [ TiO2 ], [ Ti2O3 ], and [ Ti3O5 ], and the total of the Ti oxide converted into TiO2 is expressed as [converted TiO2 ], which is calculated by the following formula 1.
  • [Converted TiO 2 ] (0.60 ⁇ [TiO 2 ]+0.67 ⁇ [Ti 2 O 3 ]+0.64 ⁇ [Ti 3 O 5 ]) ⁇ 1.67
  • the coefficients (0.60, 0.67, 0.64) in Equation 1 are coefficients for calculating the amount of Ti contained in each oxide, and the multiplier (1.67) at the end is a multiplier for calculating the TiO2 equivalent value from the total amount of Ti present as an oxide in the wire.
  • the 1.67 in formula 1 corresponds to the multiplier calculated in formula 3 above.
  • the oxide may be a compound that combines two metal elements.
  • the sum of the SiO2 equivalent values of Si oxides, the sum of the ZrO2 equivalent values of Zr oxides, the sum of the Al2O3 equivalent values of Al oxides, the sum of the MgO equivalent values of Mg oxides, the sum of the Na2O equivalent values of Na oxides, the sum of the K2O equivalent values of K oxides, the sum of the CaO equivalent values of Ca oxides, the sum of the MnO2 equivalent values of Mn oxides, and the sum of the FeO equivalent values of Fe oxides are also obtained by the same calculation as the sum of the TiO2 equivalent values of Ti oxides.
  • the flux collected by the X-ray fluorescence analyzer and the X-ray diffraction (XRD) device is analyzed, and the coefficients and multipliers are calculated according to the various oxides detected in accordance with the above formulas 2, 3, and 4, and the calculation is performed in the same manner as the above formula 1.
  • Representative oxides detected by analysis are listed below.
  • Si oxides SiO, SiO2 , Si2O3 , Si2O4 Zr oxide; ZrO2 Al oxide: AlO , Al2O3 , Al3O5 Mg oxide; MgO, MgO2 , Mg2O Na oxide; Na2O , Na2O2 K oxide; K2O , KO2 Ca oxide; CaO, CaO2 Mn oxides; MnO, Mn2O , MnO2 Fe oxides: FeO , Fe2O4 , FeO3
  • the method for separating the steel sheath from the flux when analyzing various compositions such as Ti oxides is as follows. Use pliers or similar tools to open the steel sheath of the flux-cored wire and extract the internal flux. In addition, use a wire brush and ultrasonic cleaning to remove any flux adhering to the inner surface of the steel sheath, which is in contact with the flux. This separates the steel sheath from the flux.
  • Silicon oxides increase the oxygen content in the weld metal and deteriorate the low-temperature toughness. Therefore, from the viewpoint of low-temperature toughness, it is preferable that silicon oxides are not contained, and the lower limit of the total value of silicon oxides calculated as SiO2 is set to 0%.
  • silicon oxide is a slag component that has the effect of increasing the viscosity of molten slag and improving the removability of the slag, and therefore may be contained from this viewpoint.
  • the slag encapsulation state is improved, the slag removability is enhanced, and the bead shape and bead appearance can be improved. Also, the welding workability (especially vertical welding ability) can be ensured.
  • the total of the SiO2 converted values of the Si oxides 1.00% or less the amount of oxygen in the weld metal can be suppressed, and low-temperature toughness can be ensured.
  • the amount of spatter generation can be suppressed.
  • the generation of pits and gas grooves can be suppressed. Also, the generation of slag inclusion can be suppressed.
  • the total SiO2 equivalent value of silicon oxide is preferably 0 to 1.00%.
  • the lower limit of the total value of silicon oxide calculated as SiO2 is more preferably 0.05%, 0.10%, 0.15%, 0.20%, or 0.25%.
  • the upper limit of the total amount of silicon oxides calculated as SiO2 is more preferably 0.95%, 0.90%, or 0.85%.
  • silicon oxides can exist mainly as silica sand, zircon sand, feldspar, sodium silicate, potassium silicate, etc. in the flux. Therefore, the above-mentioned range of silicon oxide content can be achieved mainly by controlling the silicon oxide content of the flux.
  • Zr oxide increases the oxygen content in the weld metal and deteriorates low-temperature toughness. Therefore, from the viewpoint of low-temperature toughness, it is preferable that Zr oxide is not contained, and the lower limit of the total Zr oxide calculated as ZrO2 is set to 0%.
  • Zr oxide is a slag component and has the effect of improving slag coverage in horizontal fillet welding and smoothing the bead shape, so it may be contained from this viewpoint.
  • ZrO2 equivalent value of Zr oxide 0.80% or less, it is possible to prevent the bead shape from becoming convex. Also, it is possible to prevent the occurrence of slag inclusion.
  • the total Zr oxide calculated as ZrO2 is preferably set to 0 to 0.80%.
  • the upper limit of the total amount of Zr oxide calculated as ZrO2 is more preferably 0.60%, 0.40%, 0.20%, or 0.10%.
  • Zr oxide is mainly present in the flux as zircon sand, zirconium oxide, etc., and may also be contained in trace amounts in Ti oxide. Therefore, the above-mentioned range of Zr oxide content can be achieved mainly by controlling the Zr oxide content of the flux.
  • Total of Al oxide converted into Al 2 O 3 0 to 0.80% by mass
  • Al oxide is an oxygen source
  • the addition of Al oxide increases the amount of oxygen in the weld metal, which causes deterioration of toughness. Therefore, from the viewpoint of low temperature toughness, it is preferable not to include Al oxide, and the lower limit of the total Al oxide content calculated as Al2O3 is set to 0%.
  • the total content of Al oxide calculated as Al 2 O 3 is preferably set to 0 to 0.80%.
  • the upper limit of the total content of Al oxide calculated as Al 2 O 3 is more preferably 0.70%, 0.60%, 0.40%, 0.20%, or 0.10%.
  • aluminum oxides are often present mainly as components of alumina, feldspar, etc. in the flux. Therefore, the above-mentioned range of aluminum oxide content can be achieved mainly by controlling the aluminum oxide content of the flux.
  • K2SiF6 , K2ZrF6 , NaF, Na3AlF6 , CaF2 , and MgF2 have the effect of reducing the oxygen content in the weld metal.
  • specific fluorides By ensuring that the total content of specific fluorides is 0.10% or more, the oxygen content of the weld metal does not become too high, and low-temperature toughness can be ensured.
  • the total content of specific fluorides at 2.00% or less, the generation of welding fumes can be reduced, and the occurrence of welding defects can be suppressed.
  • the total content of one or more of the specific fluorides is 0.10 to 2.00%.
  • the lower limit for the total amount of particular fluorides is more preferably 0.20%, 0.30%, or 0.40%.
  • the upper limit for the total of particular fluorides is more preferably 1.90%, 1.80%, or 1.70%.
  • each fluoride is measured by X-ray fluorescence analysis and X-ray diffraction (XRD) in the same manner as the Ti oxide content described above.
  • Total of Na-containing compounds 0.01 to 2.00% by mass
  • Na oxides, NaF, and Na 3 AlF 6 decompose during welding, and Na acts as a deoxidizer to reduce the oxygen content in the weld metal, thereby improving the low-temperature toughness of the weld metal.
  • the total content of the specific Na-containing compounds is 0.01% or more
  • the oxygen content of the weld metal can be reduced, and low-temperature toughness can be ensured.
  • the total content of the specific Na-containing compounds 2.00% or less the solidification temperature of the welding slag can be prevented from becoming lower, and welding workability (particularly vertical welding ability) can be ensured.
  • the specific Na-containing compounds in a total amount of 0.01 to 2.00%.
  • the lower limit of the total amount of the specific Na-containing compounds is more preferably 0.05%, 0.15%, 0.20%, or 0.30%.
  • the upper limit of the total amount of the specific Na-containing compounds is more preferably 1.90%, 1.80%, 1.70%, or 1.50%.
  • the content of Na oxide means the total Na 2 O converted value of Na oxide.
  • K decomposed during welding acts as a deoxidizer and reduces the amount of oxygen in the weld metal, thereby improving the low-temperature toughness of the weld metal.
  • the oxygen content in the weld metal can be reduced, and low-temperature toughness can be ensured.
  • the total amount of the specific K-containing compounds 2.00 or less the solidification temperature of the welding slag can be prevented from being lowered, and welding workability (particularly vertical welding ability) can be ensured.
  • the specific K-containing compounds in a total amount of 0.01 to 2.00%.
  • the lower limit of the total amount of the specific K-containing compounds is more preferably 0.05%, 0.20%, 0.30%, or 0.40%.
  • the upper limit of the total amount of the specific K-containing compounds is more preferably 1.95%, 1.90%, 1.80%, or 1.50%.
  • the content of K oxides means the total of K 2 O converted values of K oxides.
  • the flux-cored wire according to the present embodiment may contain at least one Mg-containing compound selected from the group consisting of Mg oxide and MgF2 , in addition to the specific Na-containing compound and the specific K-containing compound.
  • Mg oxides and MgF2 (hereinafter, these Mg-containing compounds may be referred to as "specific Mg-containing compounds") decompose during welding, and the Mg acts as a deoxidizer to reduce the oxygen content in the weld metal, thereby improving the low-temperature toughness of the weld metal.
  • the total content of the specific Mg-containing compounds is 0.01% or more, the effect of reducing the oxygen content in the weld metal is increased, and the low-temperature toughness is further improved.
  • the total content of the specific Mg-containing compounds is 2.00% or less, the solidification temperature of the welding slag increases, and the welding workability (particularly vertical welding ability) is improved.
  • the total content of one or more specific Mg-containing compounds is preferably 0 to 2.00%, and when an Mg-containing compound is contained, the total content is preferably 0.01 to 2.00%.
  • the lower limit of the total amount of the specific Mg-containing compounds is more preferably 0.20%, 0.30%, or 0.40%.
  • the upper limit of the total amount of the specific Mg-containing compounds is more preferably 1.90%, 1.80%, or 1.70%.
  • the content of Mg oxide means the total amount of Mg oxide calculated as MgO.
  • the wire contains the specific Na-containing compound and the specific K-containing compound in the above-mentioned ranges, respectively. From a similar viewpoint, it is also preferable that the wire contains a specific Mg-containing compound in the above range.
  • the contents of the specific Mg-containing compound, the specific Na-containing compound, and the specific K-containing compound are expressed in mass % relative to the total mass of the flux-cored wire.
  • the X value calculated by formula A is preferably 0.10 to 160.00.
  • X (8xCaF2 + 5xMgF2 + 5xNaF + 5xK2SiF6 + 5xK2ZrF6 + Na3AlF6 ) / ( SiO2 + Al2O3 + ZrO2 + 0.5xMgO + CaO + 0.5xNa2O + 0.5xK2O + MnO2 + FeO ) ...
  • CaF2 , MgF2 , NaF, K2SiF6 , K2ZrF6 , and Na3AlF6 are the contents of the compounds represented by each chemical formula in mass% relative to the total mass of the flux-cored wire.
  • SiO2 represents the total of the SiO2 equivalent value of Si oxide
  • Al2O3 represents the total of the Al2O3 equivalent value of Al oxide
  • ZrO2 represents the total of the ZrO2 equivalent value of Zr oxide
  • MgO represents the total of the MgO equivalent value of Mg oxide
  • CaO represents the total of the CaO equivalent value of Ca oxide
  • Na2O represents the total of the Na2O equivalent value of Na oxide
  • K2O represents the total of the K2O equivalent value of K oxide
  • MnO2 represents the total of the MnO2 equivalent value of Mn oxide
  • FeO represents the total of the FeO equivalent value of Fe oxide.
  • the SiO2 converted value, the Al2O3 converted value, the ZrO2 converted value, the MgO converted value, the CaO converted value, the Na2O converted value, the K2O converted value, the MnO2 converted value, and the FeO converted value in Formula A are expressed in mass% with respect to the total mass of the flux-cored wire.
  • the numerator is an index of the amount of compounds that decompose during welding, function as a deoxidizer, and reduce the amount of oxygen in the weld metal (Ca, Mg, Na, K, Si), and that contain fluorine, which reduces the amount of diffusible hydrogen in the weld metal.
  • the denominator is an index of the amount of compounds containing oxygen (O) that increase the oxygen content of the weld metal.
  • the X value when the X value is 0.10 or more, the amount of compounds containing oxygen (O) that increase the oxygen content of the weld metal is small, the effect of reducing the oxygen content of the weld metal is large, and the low temperature toughness is further improved.
  • the X value is 160.00 or less, the amount of fluoride is not too large, slag inclusion is unlikely to occur, and a sound joint can be easily produced.
  • the value of X calculated by formula A is preferably set to 0.10 to 160.00.
  • the lower limit of the X value is more preferably 1.00, 5.00, or 10.00.
  • the upper limit of the X value is more preferably 130.00, 100.00, 70.00, 50.00, or 20.00.
  • the total content of the other oxides is calculated as the sum of the Fe oxide (converted into FeO), the Mg oxide (converted into MgO), the Na oxide (converted into Na2O ), the K oxide (converted into K2O ), the Mn oxide (converted into MnO2) , and the Ca oxide (converted into CaO).
  • the lower limit of the total content of the other oxides in the flux-cored wire is 0%.
  • the other oxides have the effect of maintaining the weld bead shape well and the effect of improving vertical weldability.
  • Mg oxide, Fe oxide, and the like also have the effect of stabilizing the arc.
  • the total content of the other oxides may be more than 0%.
  • the lower limit of the total content of the other oxides may be 0.05%, 0.10%, 0.15%, or 0.20%.
  • the upper limit of the total content of the other oxides is preferably 10.00%, and may be 9.00%, 8.00%, 7.00%, 6.00%, 3.00%, 2.00%, 1.00%, 0.50%, or 0.30%.
  • the content of other oxides in the flux-cored wire according to the present disclosure does not need to be limited to each type of oxide.
  • the content of each oxide in the other oxides and the total content of the other oxides are measured by X-ray fluorescence analysis and X-ray diffraction (XRD) in the same manner as the content of Ti oxide described above.
  • Nitrides, metal carbonates Nitrides (particularly nitrides in flux) reduce the amount of diffusible hydrogen in the weld metal and significantly improve the cold cracking resistance of the weld metal. The reason for this is not clear, but it is speculated that one of the reasons is that N in the nitrides combines with hydrogen (H) during welding to become ammonia ( NH3 ), and this NH3 is released outside the weld metal. Therefore, the flux-cored wire according to the present disclosure may include nitrides.
  • the flux-cored wire according to the present disclosure may contain, as the nitride, one or more types selected from the group consisting of AlN, BN , Ca3N2 , CeN, CrN, Cu3N , Fe4N , Fe3N , Fe2N , Mg3N , Mo2N , NbN , Si3N4 , TiN, VN, ZrN, Mn2N , and Mn4N .
  • the nitride one or more types selected from the group consisting of AlN, BN , Ca3N2 , CeN, CrN, Cu3N , Fe4N , Fe3N , Fe2N , Mg3N , Mo2N , NbN , Si3N4 , TiN, VN, ZrN, Mn2N , and Mn4N .
  • the flux-cored wire according to the present disclosure may contain metal carbonate in the flux.
  • the flux - cored wire according to the present disclosure may contain, as the metal carbonate, one or more selected from the group consisting of MgCO3 , Na2CO3 , LiCO3 , CaCO3 , K2CO3 , BaCO3 , FeCO3 , MnCO3 , and SrCO3 .
  • the type and composition of the metal carbonate are not limited.
  • the content of nitrides and metal carbonates is measured by X-ray fluorescence analysis and X-ray diffraction (XRD) in the same manner as the content of Ti oxide described above.
  • the flux-cored wire according to the present disclosure may further include a lubricant applied to the wire surface.
  • the lubricant applied to the wire surface has the effect of improving the wire feedability during welding.
  • Various types of lubricants for welding wires e.g., vegetable oils such as palm oil
  • PTFE oil polytetrafluoroethylene oil
  • PFPE oil perfluoropolyether oil
  • the flux-cored wire according to the present disclosure may further include a plating formed on the wire surface. In this case, the lubricant is applied to the surface of the plating.
  • the amount of hydrogen contained in the flux-cored wire according to the present disclosure is not particularly limited, but in order to reduce the amount of diffusible hydrogen in the weld metal, it is preferable that the amount be 12 ppm or less relative to the total mass of the flux-cored wire.
  • the amount of hydrogen in the flux-cored wire may increase due to moisture penetrating into the flux-cored wire during storage. Therefore, if there is a long period between the manufacture of the wire and its use, it is desirable to prevent moisture from penetrating by the means described below.
  • Flux-cored wires are usually classified into two types: wires having a shape without slit-like gaps (seamless shape) because the seam of the steel sheath is welded (wires having a weld at the seam of the steel sheath), and wires having a shape including slit-like gaps (seam shape) because the seam of the steel sheath is not welded (wires not having a weld at the seam of the steel sheath).
  • any of the shapes may be adopted.
  • the steel sheath does not have a slit-shaped gap.
  • H hydrogen
  • H 2 O moisture
  • the steel sheath has a seam, moisture in the air is likely to penetrate into the flux through the seam. For this reason, it is desirable to prevent moisture in the air from penetrating into the flux through the steel sheath between the time the wire is manufactured and the time the wire is used by removing the seam from the steel sheath. If the steel sheath has a seam and there is a long period between the time the wire is manufactured and the time the wire is used, it is desirable to vacuum package the entire flux-cored wire or store the flux-cored wire in a container that can keep it dry in order to prevent sources of H, such as moisture, from penetrating.
  • the diameter of the flux-cored wire according to the present disclosure is not particularly limited, but is, for example, ⁇ 1.0 to ⁇ 2.0 mm. Note that the diameter of a typical flux-cored wire is ⁇ 1.2 to ⁇ 1.6 mm.
  • the filling rate of the flux-cored wire according to the present disclosure is not particularly limited as long as the above-mentioned conditions are satisfied.
  • the lower limit of the filling rate of the flux-cored wire according to the present disclosure may be, for example, 8%, 10%, or 12%.
  • the upper limit of the filling rate of the flux-cored wire according to the present disclosure may be, for example, 28%, 25%, 22%, 20%, or 17%.
  • a method for manufacturing a flux-cored wire having a seamless shape includes the steps of preparing flux, forming a steel strip using a forming roll while feeding the steel strip in the longitudinal direction to obtain a U-shaped open tube, supplying flux into the open tube through the opening of the open tube, butt-welding opposing edge portions (both circumferential ends) of the opening of the open tube to obtain a seamless tube, drawing the seamless tube to obtain a flux-cored wire having a predetermined wire diameter, and annealing the flux-cored wire during or after the drawing step.
  • the flux is adjusted so that each component of the flux-cored wire falls within the above-mentioned range. Note that the width and thickness of the steel strip, which is the material of the steel sheath, and the flux filling rate, which is determined by the amount of flux filling, also affect the amount of each component of the flux-cored wire.
  • the butt welding is performed by electric resistance welding, laser welding, TIG welding, or the like.
  • the flux-cored wire is annealed to remove moisture from the flux-cored wire.
  • the annealing temperature is preferably 650° C. or more and the annealing time is preferably 4 hours or more.
  • the annealing temperature is preferably 900° C. or less.
  • the method for producing a flux-cored wire having a slit-shaped gap is the same as the method for producing a flux-cored wire having a seamless shape, except that the method includes a step of forming an open tube and butting the ends of the open tube to obtain a tube with a slit-shaped gap, instead of a step of butt-welding both circumferential ends of an open tube to obtain a seamless tube.
  • the method for producing a flux-cored wire having a slit-shaped gap may further include a step of crimping the butted ends of the open tube. In a method for producing a flux-cored wire having slit-like gaps, a tube having slit-like gaps is drawn.
  • a method for manufacturing a welded joint according to the present disclosure includes a step of welding steel materials using the flux-cored wire according to the present disclosure described above.
  • a welded joint manufactured by the welded joint manufacturing method according to the present disclosure has high strength and high toughness.
  • a welded structure having a welded joint manufactured by the welded joint manufacturing method according to the present disclosure also has high strength and high toughness at the welded joint.
  • the welding method is preferably gas-shielded arc welding.
  • the type of steel material (welded material) that serves as the base material of the welded joint is not particularly limited, but examples include steel materials with high cold cracking sensitivity having a P CM (weld crack susceptibility composition) of 0.24% or more (particularly high-strength steel plates having a tensile strength of 590 MPa or more and 1700 MPa or less and a plate thickness of 20 mm or more), and Ni-based low-temperature steel plates containing 6% to 9% Ni and having a plate thickness of 20 mm or more. Of these, Ni-based low-temperature steel plates containing 6% to 9% Ni and having a plate thickness of 20 mm or more can be preferably used.
  • the method for manufacturing a welded joint according to the present disclosure it is preferable to include a step of welding steel materials using the flux-cored wire according to the present disclosure in one or more of the first pass to the final pass.
  • the flux-cored wire according to the present disclosure is used in the one pass.
  • the polarity of the flux-cored wire may be either positive or negative since the effect on the amount of diffusible hydrogen in the weld metal and the amount of spatter generation is negligibly small, but positive polarity is preferred.
  • the type of shielding gas used in the method for producing a welded joint according to the present disclosure is not particularly limited.
  • the method for producing a welded joint according to the present disclosure can provide a welded joint with excellent welding workability and high strength and high toughness regardless of the type of shielding gas.
  • the shielding gas in the method for producing a welded joint according to the present disclosure 100% by volume carbon dioxide gas, which is commonly used, and a mixed gas of Ar and 3 to 30% by volume CO 2 can be preferably used.
  • the shielding gas used in welding using the flux-cored wire according to the present disclosure may contain 5% or less by volume O 2 gas. These gases are inexpensive, so welding using these gases is advantageous for industrial use.
  • the manufacturing method for a welded joint according to the present disclosure uses the flux-cored wire according to the present disclosure, which can sufficiently suppress the amount of spatter, and therefore, even when these gases are used as shielding gases, good welding workability can be achieved.
  • the welding position in the manufacturing method for a welded joint according to the present disclosure is not particularly limited.
  • the manufacturing method for a welded joint according to the present disclosure can provide good welding workability (especially vertical welding) regardless of whether the welding position is a downward position, a horizontal position, a vertical position, or an upward position.
  • the flux-cored wires of the present disclosure and comparative examples were manufactured by the method described below.
  • a steel strip having the chemical composition of the outer skin shown in Tables 1-A and 1-B was fed in the longitudinal direction and formed using a forming roll to obtain a U-shaped open tube. Flux was supplied into the open tube through the opening, and opposing edges of the opening of the open tube were butt-welded to obtain a seamless tube.
  • the seamless pipe was drawn to obtain a flux-cored wire without slit-like gaps, although some samples were drawn to have slit-like gaps without seam welding. In this manner, a flux-cored wire having a final wire diameter of ⁇ 1.2 mm was produced.
  • the flux-cored wires were annealed for 4 hours or more at a temperature range of 650 to 950°C. After the prototypes were made, a lubricant was applied to the wire surface. The configurations of these flux-cored wires are shown in Tables 2-A to 2-F.
  • the units for the contents of the chemical components of the sheath, the contents of the alloy components of the wire, the oxide content, the fluoride content, the content of Na-containing compounds, the content of K-containing compounds and the iron powder content shown in Tables 1-A, 1-B, and 2-A to 2-F are mass% relative to the total mass of the flux-cored wire.
  • “mass% relative to the total mass of the steel sheath” and “mass% relative to the total mass of the flux-cored wire” are both abbreviated to “mass%”
  • “metal components in the chemical composition of the wire” is abbreviated to "chemical components of the wire”.
  • the balance of the steel sheaths shown in Tables 1-A and 1-B (i.e., components other than those shown in the tables) and the balance of the flux-cored wires shown in Tables 2-A to 2-F (i.e., components other than those shown in the tables) are iron and impurities.
  • the flux-cored wires shown in Tables 2-A to 2-F the flux-cored wires described as "seamless" in the "wire structure" column have a seamless shape and are coated with palm oil as a lubricant unless otherwise specified in the "remarks" column.
  • the flux-cored wires described as "with slit-like gaps” in the "wire structure” column are wires with slit-like gaps
  • the wires described as “PTFE coated” in the “remarks” column are wires coated with PTFE oil.
  • Each element contained in the flux-cored wires shown in Tables 2-A to 2-F is in the form of a steel sheath or metal powder.
  • Tables 1-A and 1-B values outside the ranges specified in this disclosure are underlined.
  • blank spaces in the tables relating to the content of chemical components, compounds, etc. mean that the chemical components, compounds, etc. are not intentionally included. These chemical components, compounds, etc. may be unavoidably mixed in or generated.
  • the flux-cored wires of the present disclosure and the comparative examples were used to perform vertical upward gas-shielded arc welding for evaluation. Specifically, the evaluation was performed by the method described below.
  • the steel plate to be welded was 9% Ni steel (steel plate conforming to JIS G 3127:2013 SL9N590) having a thickness of 50 mm, and the type of welding gas used in the evaluation was Ar-20% CO2 gas.
  • all welding currents used in the evaluation were direct current, and all wire polarities were positive.
  • the welding conditions for the evaluation were as shown in Table 3.
  • the amount of fume produced during gas shielded arc welding using the flux-cored wires of the present disclosure and the comparative example was evaluated.
  • the amount of fumes generated by welding was measured by a total collection method using a high volume air sampler in accordance with JIS Z3930:2013 (Method for measuring fume generation in arc welding). Flux-cored wires with a fume amount of 1000 mg/min or less were rated as "passed” in terms of fume amount, and those with a fume amount of more than 1000 mg/min were rated as "failed.”
  • the three impact test pieces were rated as "excellent” when their average Charpy absorbed energy at -196°C was 34 J or more, as “passed” when their average Charpy absorbed energy was 27 J or more and less than 34 J, and as “failed” when their average Charpy absorbed energy was less than 27 J.
  • the flux-cored wire of the present disclosure produces a small amount of fume and the obtained weld metal has excellent low-temperature toughness.
  • the comparative examples did not satisfy any of the requirements defined in this disclosure and therefore failed in one or more evaluation items.
  • wires No. 1, No. 2, and No. 4 which did not contain oxides or fluorides in the flux, were slightly inferior in welding workability (especially vertical welding) compared to the other disclosed examples.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Nonmetallic Welding Materials (AREA)
PCT/JP2022/036865 2022-09-30 2022-09-30 フラックス入りワイヤ及び溶接継手の製造方法 Ceased WO2024069985A1 (ja)

Priority Applications (7)

Application Number Priority Date Filing Date Title
EP22961044.9A EP4596167A4 (en) 2022-09-30 2022-09-30 FLUID-COATED WIRE, AND METHOD FOR MANUFACTURED WELDED JOINT
CN202280062553.2A CN118119474A (zh) 2022-09-30 2022-09-30 药芯焊丝及焊接接头的制造方法
US18/579,367 US20250083264A1 (en) 2022-09-30 2022-09-30 Flux-cored wire and method of manufacturing welded joint
JP2023570047A JP7557162B2 (ja) 2022-09-30 2022-09-30 フラックス入りワイヤ及び溶接継手の製造方法
PCT/JP2022/036865 WO2024069985A1 (ja) 2022-09-30 2022-09-30 フラックス入りワイヤ及び溶接継手の製造方法
KR1020247003359A KR20240046708A (ko) 2022-09-30 2022-09-30 플럭스 코어드 와이어 및 용접 조인트의 제조 방법
TW112137419A TWI887791B (zh) 2022-09-30 2023-09-28 含助焊劑焊線及熔接接頭之製造方法

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2022/036865 WO2024069985A1 (ja) 2022-09-30 2022-09-30 フラックス入りワイヤ及び溶接継手の製造方法

Publications (1)

Publication Number Publication Date
WO2024069985A1 true WO2024069985A1 (ja) 2024-04-04

Family

ID=90476685

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2022/036865 Ceased WO2024069985A1 (ja) 2022-09-30 2022-09-30 フラックス入りワイヤ及び溶接継手の製造方法

Country Status (7)

Country Link
US (1) US20250083264A1 (https=)
EP (1) EP4596167A4 (https=)
JP (1) JP7557162B2 (https=)
KR (1) KR20240046708A (https=)
CN (1) CN118119474A (https=)
TW (1) TWI887791B (https=)
WO (1) WO2024069985A1 (https=)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN118808987A (zh) * 2024-09-14 2024-10-22 小米汽车科技有限公司 焊丝、激光拼焊结构件及其制备方法和车辆
CN119077211A (zh) * 2024-09-27 2024-12-06 广东省科学院中乌焊接研究所 一种药芯焊丝及其制备方法和应用
CN119772446A (zh) * 2025-01-23 2025-04-08 聚力新材料科技(日照)有限公司 一种钢芯焊丝及其制备方法和用途
WO2025248681A1 (ja) * 2024-05-29 2025-12-04 日本製鉄株式会社 フラックス入りワイヤ及び溶接継手の製造方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7831951B2 (ja) * 2020-12-18 2026-03-17 株式会社神戸製鋼所 フラックス入りワイヤ
TWI900045B (zh) * 2024-06-06 2025-10-01 日商日本製鐵股份有限公司 實心焊線及熔接接頭之製造方法
CN120533355A (zh) * 2025-04-25 2025-08-26 哈焊所华通（常州）焊业股份有限公司 一种低钴不锈钢药芯焊丝及其制备方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008246507A (ja) 2007-03-29 2008-10-16 Kobe Steel Ltd Ｎｉ基合金フラックス入りワイヤ
JP2009034724A (ja) * 2007-08-06 2009-02-19 Nippon Steel & Sumikin Welding Co Ltd 高強度鋼用のサブマージアーク溶接用フラックス入りワイヤ。
JP2014018852A (ja) * 2012-07-23 2014-02-03 Kobe Steel Ltd サブマージアーク溶接用フラックス入りワイヤ
JP2014050882A (ja) * 2012-08-07 2014-03-20 Nippon Steel & Sumitomo Metal ガスシールドアーク溶接用高Ｎｉフラックス入りワイヤ
JP2019025524A (ja) * 2017-07-31 2019-02-21 新日鐵住金株式会社 ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101674743B1 (ko) * 2013-11-08 2016-11-09 신닛테츠스미킨 카부시키카이샤 가스 실드 아크 용접용 플럭스 내장 와이어 및 극저온용 강의 용접 방법 및 용접 조인트의 제조 방법
JP7594173B2 (ja) * 2020-10-07 2024-12-04 日本製鉄株式会社 溶接継手の製造方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008246507A (ja) 2007-03-29 2008-10-16 Kobe Steel Ltd Ｎｉ基合金フラックス入りワイヤ
JP2009034724A (ja) * 2007-08-06 2009-02-19 Nippon Steel & Sumikin Welding Co Ltd 高強度鋼用のサブマージアーク溶接用フラックス入りワイヤ。
JP2014018852A (ja) * 2012-07-23 2014-02-03 Kobe Steel Ltd サブマージアーク溶接用フラックス入りワイヤ
JP2014050882A (ja) * 2012-08-07 2014-03-20 Nippon Steel & Sumitomo Metal ガスシールドアーク溶接用高Ｎｉフラックス入りワイヤ
JP2019025524A (ja) * 2017-07-31 2019-02-21 新日鐵住金株式会社 ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"New Edition, Introduction of Technology of Welding and Joining", 2008, JAPAN WELDING SOCIETY, SANPO PUBLICATIONS INCORPORATED, pages: 111
See also references of EP4596167A4

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025248681A1 (ja) * 2024-05-29 2025-12-04 日本製鉄株式会社 フラックス入りワイヤ及び溶接継手の製造方法
CN118808987A (zh) * 2024-09-14 2024-10-22 小米汽车科技有限公司 焊丝、激光拼焊结构件及其制备方法和车辆
CN119077211A (zh) * 2024-09-27 2024-12-06 广东省科学院中乌焊接研究所 一种药芯焊丝及其制备方法和应用
CN119772446A (zh) * 2025-01-23 2025-04-08 聚力新材料科技(日照)有限公司 一种钢芯焊丝及其制备方法和用途

Also Published As

Publication number Publication date
KR20240046708A (ko) 2024-04-09
EP4596167A4 (en) 2025-12-03
CN118119474A (zh) 2024-05-31
US20250083264A1 (en) 2025-03-13
EP4596167A1 (en) 2025-08-06
JP7557162B2 (ja) 2024-09-27
TW202421325A (zh) 2024-06-01
TWI887791B (zh) 2025-06-21
JPWO2024069985A1 (https=) 2024-04-04

Similar Documents

Publication Publication Date Title
JP7557162B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
US20220281024A1 (en) Flux-cored wire, manufacturing method of welded joint, and welded joint
JP6766867B2 (ja) フラックス入りワイヤ、溶接継手の製造方法、及び溶接継手
JP6291461B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ
JP7495653B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP6953869B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法
JP7492185B1 (ja) 被覆アーク溶接棒及び溶接継手の製造方法
JP6801494B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、および溶接継手の製造方法
JP6953870B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法
JP6953931B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法
JP6953930B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法
JP7469597B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JPWO2015068273A1 (ja) ガスシールドアーク溶接用フラックス入りワイヤ及びそのワイヤを用いた極低温用鋼の溶接方法
JP7485895B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP7783477B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP6958139B2 (ja) ガスシールドアーク溶接用フラックス入りワイヤ、及び溶接継手の製造方法
JP7674641B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP7795067B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP2017164768A (ja) ガスシールドアーク溶接用高Ｎｉフラックス入りワイヤ及び溶接継手の製造方法
JP7719349B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
JP7783478B2 (ja) フラックス入りワイヤ及び溶接継手の製造方法
WO2026063099A1 (ja) フラックス入りワイヤ及び溶接継手の製造方法

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2023570047

Country of ref document: JP

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 202280062553.2

Country of ref document: CN

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

Ref document number: 22961044

Country of ref document: EP

Kind code of ref document: A1

WWP Wipo information: published in national office

Ref document number: 18579367

Country of ref document: US

WWE Wipo information: entry into national phase

Ref document number: 2022961044

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2022961044

Country of ref document: EP

Effective date: 20250430

WWP Wipo information: published in national office

Ref document number: 2022961044

Country of ref document: EP