WO2021060173A1 - クラッド鋼板及びその製造方法 - Google Patents
クラッド鋼板及びその製造方法 Download PDFInfo
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- WO2021060173A1 WO2021060173A1 PCT/JP2020/035404 JP2020035404W WO2021060173A1 WO 2021060173 A1 WO2021060173 A1 WO 2021060173A1 JP 2020035404 W JP2020035404 W JP 2020035404W WO 2021060173 A1 WO2021060173 A1 WO 2021060173A1
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- Prior art keywords
- steel sheet
- base steel
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 163
- 239000010959 steel Substances 0.000 title claims abstract description 163
- 238000004519 manufacturing process Methods 0.000 title claims description 14
- 238000000034 method Methods 0.000 title description 8
- 239000000463 material Substances 0.000 claims abstract description 82
- 239000000203 mixture Substances 0.000 claims abstract description 27
- 229910001563 bainite Inorganic materials 0.000 claims abstract description 18
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 17
- 239000012535 impurity Substances 0.000 claims abstract description 11
- 239000013078 crystal Substances 0.000 claims abstract description 10
- 239000002648 laminated material Substances 0.000 claims description 55
- 238000005096 rolling process Methods 0.000 claims description 20
- 229910045601 alloy Inorganic materials 0.000 claims description 17
- 239000000956 alloy Substances 0.000 claims description 17
- 229910052804 chromium Inorganic materials 0.000 claims description 15
- 229910052802 copper Inorganic materials 0.000 claims description 15
- 229910052759 nickel Inorganic materials 0.000 claims description 15
- 230000009467 reduction Effects 0.000 claims description 13
- 239000010935 stainless steel Substances 0.000 claims description 11
- 229910001220 stainless steel Inorganic materials 0.000 claims description 11
- 230000009466 transformation Effects 0.000 claims description 10
- 238000010030 laminating Methods 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 5
- 238000005253 cladding Methods 0.000 abstract description 2
- 239000010953 base metal Substances 0.000 description 25
- 230000000052 comparative effect Effects 0.000 description 21
- 238000010438 heat treatment Methods 0.000 description 15
- 229910001566 austenite Inorganic materials 0.000 description 11
- 230000000694 effects Effects 0.000 description 11
- 238000005728 strengthening Methods 0.000 description 7
- 238000005260 corrosion Methods 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 6
- 238000001556 precipitation Methods 0.000 description 6
- 230000006872 improvement Effects 0.000 description 5
- 150000004767 nitrides Chemical class 0.000 description 5
- 230000007704 transition Effects 0.000 description 4
- 238000003466 welding Methods 0.000 description 4
- 229910000975 Carbon steel Inorganic materials 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000010962 carbon steel Substances 0.000 description 3
- 239000000571 coke Substances 0.000 description 3
- 239000007799 cork Substances 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 3
- 229910052748 manganese Inorganic materials 0.000 description 3
- 229910052758 niobium Inorganic materials 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 229910001567 cementite Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 238000009863 impact test Methods 0.000 description 2
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- 239000002023 wood Substances 0.000 description 2
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- -1 V: 0.005 to 0.030% Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 238000005987 sulfurization reaction Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/02—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling heavy work, e.g. ingots, slabs, blooms, or billets, in which the cross-sectional form is unimportant ; Rolling combined with forging or pressing
- B21B1/026—Rolling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/22—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling plates, strips, bands or sheets of indefinite length
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/38—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling sheets of limited length, e.g. folded sheets, superimposed sheets, pack rolling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
- B21B3/02—Rolling special iron alloys, e.g. stainless steel
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- 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
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
-
- 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
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/04—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating by means of a rolling mill
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/28—Normalising
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/46—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- 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
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
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- 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
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- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- 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
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- 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
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- 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
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- 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
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/38—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling sheets of limited length, e.g. folded sheets, superimposed sheets, pack rolling
- B21B2001/383—Cladded or coated products
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/002—Bainite
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/005—Ferrite
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- 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
Definitions
- the present invention relates to a clad steel sheet used for, for example, a cork drum and a method for manufacturing the clad steel sheet.
- a clad steel sheet is a steel sheet in which a laminated material made of a corrosion-resistant alloy is bonded to a base steel sheet such as carbon steel.
- the clad steel sheet has both mechanical properties as a structural member and corrosion resistance, and has a feature that it is cheaper than a solid wood corrosion resistant alloy. Therefore, clad steel sheets are widely used in industrial fields such as shipbuilding, pressure vessels, and energy fields, and demand is increasing against the background of an increase in properties with severe corrosive environments in resource development.
- a clad steel sheet used for, for example, a pressure vessel a clad steel sheet using 1Cr-1 / 2Mo steel or the like, which has higher high temperature strength than carbon steel, as a base material (see, for example, Patent Document 1) has been known.
- a cork drum used in the delayed caulking process 1.1 / 4Cr-1 / 2Mo steel and 1Cr-1 / 2Mo steel are often used, and in some cases 1 / 2Mo steel is used. is there.
- the operating temperature is about 440 ° C to 500 ° C and the operating pressure is about 1 to 7 kg / cm 2 G during operation, and when coke is taken out, a cycle of normal temperature and atmospheric pressure is performed every 16 to 24 hours. Repeated. Meanwhile, the interior of the coke drum for a H 2 S environment, as a high-temperature sulfurization countermeasure, Ni based alloys such as 13Cr stainless steel or Alloy625 as the cladding material SUS405 and SUS410S is employed.
- the base material made of 1 / 2Mo steel in the clad steel sheet manufactured by normalizing as described above has a double-phase structure of ferrite having a coarse microstructure and hard bainite. Therefore, it is known that the toughness of the base metal is significantly deteriorated, and it is difficult to achieve both the strength of the base metal and the toughness of the base metal.
- the present invention has been developed in view of the above-mentioned current situation, and an object of the present invention is to provide a clad steel sheet having both base material strength and base material toughness together with a manufacturing method thereof.
- the present invention has been made to achieve the above object, and the gist thereof is as follows.
- the composition of the base steel sheet is mass%.
- the area ratio of bainite at the plate thickness 1/2 position in the plate thickness direction of the base steel plate is 20% or more, and the average crystal grain size of ferrite at the plate thickness 1/2 position in the plate thickness direction is 15 ⁇ m or less.
- the composition of the base steel sheet is further increased by mass%.
- the composition of the base steel sheet is further in mass%, V: 0.005 to 0.030%, Ti: 0.005 to 0.030%, Ca: 0.0005 to 0.0040%.
- a method for producing a clad steel sheet in which the rolled plate is subjected to normalizing at a temperature of 1/2 of the plate thickness in the plate thickness direction of the base steel plate at an Ac 3 transformation point or more and 1000 ° C. or less twice or more.
- An assembled slab in which a base steel sheet material having the component composition of the base steel sheet according to any one of [1] to [3] and a laminated material made of a Ni-based alloy are assembled at a surface temperature. Heat to a temperature range of 1050 ° C to 1200 ° C, A rolled plate is produced by rolling the heated assembled slab so that the rolling reduction ratio is 2.0 or more in a temperature range of 950 ° C. or higher and the rolling end temperature is 800 ° C.
- a method for producing a clad steel sheet in which the rolled plate is subjected to normalizing at a temperature of 1/2 of the plate thickness in the plate thickness direction of the base steel plate at an Ac 3 transformation point or more and 1000 ° C. or less twice or more.
- the assembled slabs are laminated in the order of the base steel plate material, the laminated material, the laminated material, and the base steel plate material, or the base steel plate material and the laminated material are laminated.
- the method for producing a clad steel sheet according to [6] or [7].
- the toughness of the base metal can be ensured by setting the diameter to 15 ⁇ m or less.
- the clad steel has a structure in which a laminated material is joined to one side or both sides of a base material.
- the laminated material include, but are not limited to, corrosion-resistant stainless steel or Ni-based alloys, and various alloys can be used depending on the application.
- the thickness of the clad steel sheet is, for example, about 70 mm, but the thickness is not limited to this. Further, usually, the plate thickness of the base steel plate is about 5 to 66 mm, and the plate thickness of the laminated material is about 1.5 to 4.0 mm.
- the composition of the base steel plate is C: 0.120 to 0.180%, Si: 0.15 to 0.40%, Mn: 0.50 to 0.90%, P: 0.020 in mass%. % Or less, S: 0.010% or less, Cu + Ni + Cr: 0.800 to 1.100% (however, each element symbol indicates the content of each element), Mo: 0.45 to 0.60%, Nb : 0.005 to 0.025%, Al: 0.005 to 0.050%, N: 0.0010 to 0.0070%.
- each component composition will be described in detail.
- C 0.120 to 0.180% C is an element that contributes to precipitation strengthening as a carbide.
- the C content is less than 0.120%, sufficient strength of the base metal cannot be secured.
- the C content exceeds 0.180%, the toughness of the base metal and the toughness of the weld heat-affected zone are deteriorated due to the precipitation of coarse carbides (cementite). Therefore, the C content is set to 0.120 to 0.180%.
- the preferred upper limit is 0.165%.
- Si 0.15 to 0.40% Si is an element added to secure the strength of the base metal by deoxidizing or strengthening the solid solution.
- the Si content is less than 0.15%, the effect is not sufficient.
- the Si content exceeds 0.40%, the toughness of the base metal and the toughness of the weld heat affected zone are deteriorated. Therefore, the Si content is set to 0.15 to 0.40%.
- the preferred lower limit is 0.20%.
- Mn 0.50 to 0.90%
- Mn is an element added to ensure the strength of the base metal and the toughness of the base metal by improving the hardenability.
- the Mn content is set to 0.50 to 0.90%.
- the preferred lower limit is 0.70%.
- P 0.020% or less
- P is an unavoidable impurity that deteriorates the toughness of the base metal. Therefore, the P content is 0.020% or less. It is preferably 0.0080% or less.
- S 0.010% or less
- S generally exists as a sulfide-based inclusion in steel and deteriorates the toughness of the base metal. Therefore, it is preferable to reduce S as much as possible, and the S content is 0.010% or less. It is preferably 0.0050% or less.
- Mo 0.45 to 0.60%
- Mo contributes to increasing the strength of the base steel sheet by strengthening precipitation.
- the Mo content is less than 0.45%, the effect is not sufficient.
- the Mo content exceeds 0.60%, the toughness of the weld heat affected zone may deteriorate. Therefore, when Mo is contained, the content thereof is set to 0.45 to 0.60% or less.
- the preferred lower limit is 0.50%.
- Nb 0.005 to 0.025%
- Nb contributes to increasing the strength of the base steel sheet by strengthening precipitation and increasing hardenability. Further, Nb forms a carbonitride, and the pinning effect of the carbonitride suppresses the coarsening of austenite, which contributes to the improvement of the toughness of the base metal.
- the Nb content is preferably 0.005% or more, preferably 0.015% or more.
- the Nb content is 0.025% or less, preferably 0.020% or less.
- Al 0.005 to 0.050%
- Al is an element that suppresses the coarsening of austenite by the pinning effect of the nitride and contributes to the improvement of the toughness of the base metal. It is also an element added for deoxidation. However, if the Al content is less than 0.005%, these effects are not sufficient. On the other hand, when the Al content exceeds 0.050%, alumina clusters are formed and the ductility is deteriorated. Therefore, the Al content is set to 0.005 to 0.050%. The preferred lower limit is 0.020%.
- N 0.0010 to 0.0070%
- the coarsening of austenite is suppressed by the pinning effect of the nitride, which contributes to the improvement of the toughness of the base metal and the heat-affected zone of welding.
- the N content is set to 0.0010 to 0.0070%.
- the preferred lower limit is 0.0020%.
- Cu + Ni + Cr 0.800 to 1.100% (However, each element symbol indicates the content of each element.)
- Cu, Ni, and Cr are all elements that improve hardenability, and are elements that are added to ensure the strength of the base metal and the toughness of the base metal.
- the total content of Cu, Ni, and Cr is preferably 0.800% or more, preferably 0.950% or more.
- the total content of Cu, Ni, and Cr is set to 1.100% or less.
- Cu, Ni, and Cr it is not necessary to contain all the elements of Cu, Ni, and Cr, and it is sufficient that any one or two of them are contained to satisfy the above total content.
- Cu, Ni, and Cr Cu: 0.30 to 0.40%, Ni: 0.30 to 0.40%, and Cr: 0.20 to 0.30%, respectively. You may. If the Cu content is less than 0.30%, the Ni content is less than 0.30%, or the Cr content is less than 0.20%, a sufficient strength-toughness balance cannot be ensured. Therefore, when Cu, Ni, and Cr are contained, the Cu content is preferably 0.30% or more and preferably 0.35% or more, and the Ni content is 0.30% or more and 0.
- the Cr content is 0.20% or more, preferably 0.25% or more.
- the Cu content is 0.40% or less, the Ni content is 0.40% or less, and the Cr content is 0.30% or less.
- V 0.005 to 0.030%
- Ti 0.005 to 0.030%
- Ca 0.0005 to 0.0040%
- One kind or two or more kinds may be contained.
- V 0.005 to 0.030%
- V contributes to increasing the strength of the base steel sheet by strengthening precipitation.
- the V content is less than 0.005%, the effect is not sufficient.
- the V content exceeds 0.030%, the toughness of the weld heat affected zone deteriorates. Therefore, when V is contained, the content thereof is set to 0.005 to 0.030% or less. A more preferable lower limit is 0.025%.
- Ti 0.005 to 0.030%
- the coarsening of austenite is suppressed by the pinning effect of the nitride, which contributes to the improvement of the toughness of the base metal and the heat-affected zone of welding.
- Ti is an element effective for increasing the strength of the steel sheet by precipitation strengthening.
- the Ti content exceeds 0.030%, the nitride becomes coarse and becomes the starting point of brittle fracture and ductile fracture. Therefore, when Ti is contained, the content thereof is set to 0.005 to 0.030%.
- the preferred upper limit is 0.020%.
- Ca 0.0005-0.0040%
- Ca has a function of fixing S in steel to improve the toughness of the base metal and the HIC resistance.
- the content thereof is set to 0.0005 to 0.0040% or less. More preferably, it is 0.0020 to 0.0030%.
- the balance of the composition components is Fe and unavoidable impurities.
- Inevitable impurities are those that are present in the raw material or are inevitably mixed in the manufacturing process, and are originally unnecessary, but they are allowed to be contained because they are in trace amounts and do not affect the characteristics. Means impurities. Therefore, even if unavoidable impurities are contained, the characteristics of the base metal do not change significantly. For example, it is permissible to contain less than 0.003% oxygen (O).
- the steel structure of the base material steel plate has a structure containing bainite. Specifically, the area ratio of bainite at the position of 1/2 of the plate thickness in the plate thickness direction of the base steel plate is set to 20% or more.
- the average crystal grain size of ferrite at the position of 1/2 of the plate thickness in the plate thickness direction of the base steel plate is set to 15 ⁇ m or less.
- the area ratio of bainite and the average grain size of ferrite will be explained below.
- the steel structure of the base steel sheet must have a structure containing bainite from the viewpoint of ensuring strength, and this bainite is transformed. By strengthening the structure, it effectively contributes to improving the strength of the steel sheet.
- the area ratio of bainite to the entire steel structure at the plate thickness 1/2 position in the plate thickness direction of the base steel plate (hereinafter, also simply referred to as the plate thickness 1/2 position) is 20% or more.
- the base steel sheet may contain bainite in an area ratio of 20% or more, may have a total area ratio of ferrite and bainite of 100%, or may contain a steel structure other than ferrite and bainite. It may be something to do.
- the area ratio of bainite at the position where the plate thickness is 1/2 is obtained as follows. That is, the area ratio is such that the L cross section (cross section parallel to the rolling direction and parallel to the rolling surface normal direction) at the plate thickness 1/2 position in the plate thickness direction of the base steel plate is mirror-polished and then corroded by night tar. It was obtained by observing a 1.2 mm 2 region selected artificially with an optical microscope at a magnification of 100 times and analyzing the image.
- Average crystal grain size of ferrite 15 ⁇ m or less Since the grain boundaries of ferrite serve as resistance to brittle crack propagation, miniaturization of crystal grains contributes to the improvement of base metal toughness. Therefore, the average crystal grain size of ferrite is set to 15 ⁇ m or less. The average crystal grain size of ferrite was evaluated in accordance with JIS G 0551.
- the laminated material bonded to the base steel plate is made of, for example, a corrosion-resistant alloy.
- the corrosion-resistant alloy is not particularly limited, but it is preferably a stainless steel such as SUS405 or SUS410S or a Ni-based alloy.
- the assembled slab is heated to a temperature range of ° C, rolled at a surface temperature range of 950 ° C or higher at a reduction ratio according to the type of laminated material, and then air-cooled to be a rolled plate composed of a base steel plate and a laminated material.
- Is produced, and the produced rolled plate is subjected to normalizing twice or more at an Ac 3 transformation point or more and 1000 ° C. or less at a temperature of 1/2 of the plate thickness in the plate thickness direction of the base steel plate.
- the material of the base material steel plate and the material of the base material are laminated, or the material of the base material steel plate, the material of the laminated material, the material of the laminated material, and the material of the base material steel plate are in this order. Assembled by stacking. When laminating the laminated materials, a release agent is applied in advance between the laminated materials, and after the normalizing process is completed, the upper part and the lower part are peeled off to form one side of the base steel plate which becomes the product plate. A clad steel sheet to which the normalizing material is bonded can be obtained. Further, the assembly slab is formed by electron beam welding or laser beam welding of base steel sheets in an environment of vacuum (negative pressure) of 10 -4 torr or less, and temporarily attaching the base steel sheets and the laminated material. There may be.
- the slab heating temperature is set to 1050 ° C to 1200 ° C. It is preferably 1050 to 1100 ° C.
- the reduction ratio is set according to the type of the laminated material.
- the reduction ratio of the material to be rolled in a temperature range of 950 ° C. or higher needs to be 1.5 or higher.
- the reduction ratio in the temperature range of the surface temperature of 1000 ° C. or higher is 2.0 or higher.
- the rolling reduction ratio in the temperature range of the surface temperature of the material to be rolled is 950 ° C. or higher must be 2.0 or higher.
- the reduction ratio in the temperature range of the surface temperature of 1000 ° C. or higher is 2.5 or higher.
- the rolling end temperature is 800 ° C. or higher at the surface temperature of the assembled slab.
- Normalizing temperature Normalizing at a temperature of 1/2 of the plate thickness at an Ac 3 transformation point or more and 1000 ° C. or less After the above clad rolling, the rolled plate is heated to perform normalizing.
- the normalizing temperature referred to here is the temperature at the position of 1/2 of the plate thickness in the plate thickness direction in the base steel plate portion of the rolled plate. If the normalizing temperature is less than the Ac 3 transformation point, the austenite transformation is not completed, the final structure becomes non-uniform, and the toughness of the base steel sheet deteriorates.
- the normalizing temperature is set to the Ac 3 transformation point or more and 1000 ° C. or less. It is preferably 900 ° C. to 1000 ° C.
- the Ac 3 transformation point can be obtained by the following equation (1).
- Ac 3 (° C.) 912.0-230.5 x C + 31.6 x Si? 20.4 x Mn? 39.8 x Cu? 18.1 x Ni? 14.8 x Cr + 16.8 x Mo ... (1)
- the element symbol in the above formula (1) means the content (mass%) of each element, and is set to zero when the element is not contained.
- the ferrite of the final structure is refined by increasing the ferrite metamorphic nucleation sites due to the miniaturization of austenite during normalizing.
- the particle size of austenite during heating during normalizing is affected by the particle size of the pre-normalizing structure and the dispersed state of the precipitates during normalizing.
- the austenite during heating of the normalizing is refined.
- the clad steel sheet needs to be rolled at a high temperature in order to ensure the bondability between the laminated material and the base material, and the pre-normalizing structure of the base material is that the base material is not clad but carbon steel alone.
- the number of normalizing is set to 2 or more.
- the mutual relationship between the temperatures at the time of heating each normalizing is not particularly limited and may be appropriately selected.
- Example 1 a material of a base steel sheet having the component composition shown in Table 1 below was prepared.
- the laminated material was stainless steel made of SUS410S.
- the underlined portion means that it is outside the scope of the present invention, and “-” means that it is not contained or is contained as an unavoidable impurity.
- test piece shape No. 4, test piece collection position: plate thickness 1/2 position, test piece collection direction: C direction, test temperature: room temperature
- test piece conforming to JIS Z2241 were performed on the clad steel plate thus obtained.
- a Charpy impact test (notch shape: V notch, test piece collection position: plate thickness 1/2 position, test piece collection direction: C direction) based on JIS Z2242 was carried out, and yield strength (YS) and tensile strength (TS) were performed. ), The ductile brittle transition temperature (vTrs) was determined.
- the position where the test piece is collected in the tensile test and the Charpy impact test is the position where the plate thickness is 1/2 means that the plate thickness of the base steel plate is 1/2.
- the tensile strength TS (Toughness Strength) ⁇ 515 [MPa] (after baking, after PWHT 640 ° C-3 hr, after PWHT 640 ° C-21 hr) at the plate thickness 1/2 position in the plate thickness direction of the base steel plate.
- Yield strength YS Yield Strength
- Yield Strength ⁇ 295 [MPa] (after baking, after PWHT640 ° C-21hr), yield strength YS ⁇ 390 [MPa] (after PWHT640 ° C-3hr), ductile brittle transition temperature vTrs ⁇ -
- a material having a temperature of 10 [° C.] (after PWHT 640 ° C.-21 hr) satisfies the characteristics (base material strength and base material toughness) required for a clad steel plate for a pressure vessel such as a cork drum used at 300 ° C. or higher, for example. It was evaluated as a thing.
- Comparative example No. 22 the desired base material toughness cannot be obtained because the number of times of normalizing is less than the appropriate range. Comparative example No. 23, since the slab heating temperature exceeds the appropriate range, the desired base material toughness cannot be obtained.
- the strength of the base material and the toughness of the base material of the clad steel sheet are improved by controlling the steel structure of the base steel sheet in addition to controlling the composition of the components. Was done.
- Example 2 a material of a base steel sheet having the same composition as that of Example 1 shown in Table 1 described above was prepared. However, the material of the laminated material was a Ni-based alloy made of Alloy625.
- Example 2 The same evaluation test as in Example 1 was carried out on the clad steel sheet thus obtained, and the yield strength (YS), tensile strength (TS), ductile brittle transition temperature (vTrs) and joint interfacial shear strength were determined. These results are shown in Table 5.
- Comparative Example No. 26 since the C, Mn and Mo contents of the base steel sheet are below the appropriate range, the amount of bainite generated during cooling is also small, and the desired tensile properties cannot be obtained. Comparative Example No. 33, since the C and Si contents of the base steel sheet exceed the appropriate range, the desired base material toughness cannot be obtained. Comparative Example No. 34, the C content of the base steel sheet is above the appropriate range, and the total content of Cu, Ni, and Cr is below the appropriate range, so that the desired base material toughness cannot be obtained. Comparative Example No. In No. 35, the Al, Nb and N contents are below the appropriate range, so that the desired base metal toughness cannot be obtained.
- Comparative Example No. 40 the slab heating temperature is above the appropriate range and the number of times of normalizing is below the appropriate range, so that the desired base material toughness cannot be obtained. Comparative Example No. 41, since the slab heating temperature and the reduction ratio at 950 ° C. or higher are below the appropriate range, the desired bondability between the base steel sheet and the laminated material cannot be obtained. Comparative Example No. 42, the desired base material toughness cannot be obtained because the normalizing temperature is below the appropriate range. Comparative Example No. In No. 43, since the normalizing temperature exceeds the appropriate range, the desired base material characteristics cannot be obtained. Comparative Example No. In No. 40, the slab heating temperature is above the appropriate range and the number of times of normalizing is below the appropriate range, so that the desired base material toughness cannot be obtained. Comparative Example No. In No. 41, since the slab heating temperature and the reduction ratio at 950 ° C. or higher are below the appropriate range, the desired bondability between the base steel sheet and the laminated material cannot be obtained. Comparative Example No. In No. 42,
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Abstract
Description
[1] 母材鋼板に合せ材が接合されているクラッド鋼板であって、
母材鋼板に合せ材が接合されているクラッド鋼板であって、
前記母材鋼板の成分組成は、質量%で、
C:0.120~0.180%、
Si:0.15~0.40%、
Mn:0.50~0.90%、
P:0.020%以下、
S:0.010%以下、
Mo:0.45~0.60%、
Nb:0.005~0.025%、
Al:0.005~0.050%、および
N:0.0010~0.0070%、
を含有し、さらに、Cu、Ni、Crを、
Cu+Ni+Cr:0.800~1.100%、
(ただし、各元素記号は各元素の含有量を示す。)
を満足する範囲で含有し、残部がFe及び不可避的不純物からなり、
前記母材鋼板の板厚方向の板厚1/2位置におけるベイナイトの面積率は20%以上であり、板厚方向の板厚1/2位置におけるフェライトの平均結晶粒径は15μm以下であるクラッド鋼板。
[2] 前記母材鋼板の成分組成が、さらに質量%で、
Cu:0.30~0.40%、
Ni:0.30~0.40%、
Cr:0.20~0.30%、
を含有することを特徴とする[1]に記載のクラッド鋼板。
[3] 前記母材鋼板の成分組成が、さらに質量%で、V:0.005~0.030%、Ti:0.005~0.030%、Ca:0.0005~0.0040%のうちから選ばれた1種または2種以上を含有する[1]又は[2]に記載のクラッド鋼板。
[4] 前記合せ材は、ステンレス鋼からなる[1]~[3]のいずれかに記載のクラッド鋼板。
[5] 前記合せ材は、Ni基合金からなる[1]~[3]のいずれかに記載のクラッド鋼板。
[6] [1]~[3]のいずれかに記載の母材鋼板の成分組成を有する母材鋼板の素材とステンレス鋼からなる合せ材の素材とを組み立てた組立スラブを、表面温度で1050℃~1200℃の温度域に加熱し、
加熱した前記組立スラブに表面温度950℃以上の温度域での圧下比1.5以上とする圧延を施して圧延板を作製し、
前記圧延板に、前記母材鋼板の板厚方向の板厚1/2位置の温度でAc3変態点以上1000℃以下の焼きならしを2回以上施す
クラッド鋼板の製造方法。
[7] [1]~[3]のいずれかに記載の母材鋼板の成分組成を有する母材鋼板の素材とNi基合金からなる合せ材の素材とを組み立てた組立スラブを、表面温度で1050℃~1200℃の温度域に加熱し、
加熱した前記組立スラブに表面温度950℃以上の温度域での圧下比2.0以上であって、圧延終了温度を前記組立スラブの表面温度800℃以上とする圧延を施して圧延板を作製し、
前記圧延板に、前記母材鋼板の板厚方向の板厚1/2位置の温度でAc3変態点以上1000℃以下の焼きならしを2回以上施す
クラッド鋼板の製造方法。
[8] 前記組立スラブを、母材鋼板の素材、合せ材の素材、合せ材の素材、母材鋼板の素材の順に積層して、または母材鋼板の素材と合せ材の素材とを積層して組み立てる[6]または[7]に記載のクラッド鋼板の製造方法。
Cは、炭化物として析出強化に寄与する元素である。ここで、C含有量が0.120%未満では、十分な母材強度を確保できない。一方、C含有量が0.180%を超えると、粗大な炭化物(セメンタイト)の析出により、母材靭性および溶接熱影響部靱性を劣化させる。従って、C含有量は0.120~0.180%とする。好ましい上限値は0.165%である。
Siは、脱酸や固溶強化による母材強度確保のため添加する元素である。ここで、Si含有量が0.15%未満では、その効果が十分ではない。一方、Si含有量が0.40%を超えると、母材靭性や溶接熱影響部靭性を劣化させる。従って、Si含有量は0.15~0.40%とする。好ましい下限値は0.20%である。
Mnは、焼き入れ性向上による母材強度確保および母材靭性確保のため添加する元素である。ここで、Mn含有量が0.50%未満では、その効果が十分ではない。一方、Mn含有量が0.90%を超えると、溶接性が劣化する。従って、Mn含有量は0.50~0.90%とする。好ましい下限値は0.70%である。
Pは、母材靭性を劣化させる不可避的不純物である。従って、P含有量は0.020%以下とする。好ましくは0.0080%以下である。
Sは、一般に鋼中においては硫化物系介在物として存在し、母材靭性を劣化させる。従って、Sは極力低減するのが好ましく、S含有量は0.010%以下とする。好ましくは0.0050%以下である。
Moは析出強化により母材鋼板の高強度化に寄与する。ここで、Mo含有量が0.45%未満ではその効果は十分ではない。一方、Mo含有量が0.60%を超えると、溶接熱影響部の靭性を劣化させる場合がある。従って、Moを含有させる場合、その含有量は0.45~0.60%以下とする。好ましい下限値は0.50%である。
Nbは、析出強化や焼入れ性増大により母材鋼板の高強度化に寄与する。また、Nbは炭窒化物を形成し、その炭窒化物によるピンニング効果でオーステナイトの粗大化を抑制し、母材靭性向上に寄与する。しかし、Nb含有量が0.005%未満では、その効果が十分ではない。よって、Nb含有量は0.005%以上とし、0.015%以上であることが好ましい。一方、Nb含有量が0.025%を超えると、島状マルテンサイトや粗大なNb炭窒化物の生成を招き、溶接熱影響部の靭性が劣化する。従って、Nb含有量は0.025%以下とし、好ましくは0.020%以下である。
Alは、窒化物によるピンニング効果でオーステナイトの粗大化を抑制し、母材靭性向上に寄与する元素である。また、脱酸のために添加される元素である。しかし、Al含有量が0.005%未満では、これらの効果が十分ではない。一方、Al含有量が0.050%を超えると、アルミナクラスターを形成して延性を劣化させる。従って、Al含有量は0.005~0.050%とする。好ましい下限値は0.020%である。
Nは、0.0010%以上含有させることにより、窒化物によるピンニング効果でオーステナイトの粗大化を抑制し、母材や溶接熱影響部の靭性向上に寄与する。しかし、N含有量が0.0070%を超えると、溶接熱影響部の靱性が劣化する。従って、N含有量は0.0010~0.0070%とする。好ましい下限値は、0.0020%である。
Cu、Ni、Crはいずれも、焼入れ性を向上させる元素であり、母材強度確保および母材靭性確保のため添加する元素である。ここで、Cu、Ni、Crの合計含有量が0.800%未満では、十分な強度‐靱性バランスを確保できない。よって、Cu、Ni、Crの合計含有量は0.800%以上とし、0.950%以上とすることが好ましい。しかし、Cu、Ni、Crは高価な元素であるため、多量に含有させるとコストの増加を招く。従って、Cu、Ni、Crの合計含有量は1.100%以下とする。
Vは、析出強化により母材鋼板の高強度化に寄与する。ここで、V含有量が0.005%未満ではその効果が十分ではない。一方、V含有量が0.030%を超えると、溶接熱影響部の靭性が劣化する。従って、Vを含有させる場合、その含有量は0.005~0.030%以下とする。さらに好ましい下限値は0.025%である。
Tiは、0.005%以上含有させることにより、窒化物によるピンニング効果でオーステナイトの粗大化を抑制し、母材や溶接熱影響部の靭性向上に寄与する。また、Tiは、析出強化による鋼板の高強度化に有効な元素である。しかし、Ti含有量が0.030%を超えると、窒化物が粗大化し脆性破壊や延性破壊の起点となる。従って、Tiを含有させる場合、その含有量は0.005~0.030%とする。好ましい上限値は0.020%である。
Caは、鋼中のSを固定して母材靭性や耐HIC特性を向上させる働きがある。この効果を得るためには、Caを0.0005%以上含有させることが好ましい。しかし、Ca含有量が0.0040%を超えると、鋼中の介在物を増加させ、母材靭性や耐HIC特性を劣化させる場合がある。従って、Caを含有させる場合、その含有量は0.0005~0.0040%以下とする。さらに好ましくは0.0020~0.0030%である。
母材鋼板の鋼組織は、強度確保の観点からベイナイトを含む組織とする必要があり、このベイナイトは変態組織強化によって鋼板の強度向上に有効に寄与する。具体的には、母材鋼板の板厚方向の板厚1/2位置(以下、単に板厚1/2位置ともいう)における鋼組織全体に対するベイナイトの面積率で20%以上とする。なお、母材鋼板は、ベイナイトを面積率で20%以上含有するものであればよく、フェライトとベイナイトの合計の面積率が100%からなるものでもよいし、フェライトとベイナイト以外の鋼組織を含有するものであってもよい。
フェライトの結晶粒界は、脆性亀裂伝播の抵抗となるため、結晶粒の微細化は母材靭性の向上に寄与する。従って、フェライトの平均結晶粒径は15μm以下とする。なお、フェライトの平均結晶粒径はJIS G 0551に準拠して評価したものである。
スラブ加熱温度が1050℃未満では、母材鋼板と合せ材との接合性の確保が困難になる。一方、スラブ加熱温度が1200℃を超えると、母材鋼板においてオーステナイトが粗大化し、靱性が劣化する。従って、スラブ加熱温度は1050℃~1200℃とする。好ましくは1050~1100℃である。
クラッド鋼板の母材鋼板と合せ材との接合性は、高温域での圧延により確保される。すなわち、高温域での圧延では、母材鋼板と合せ材の変形抵抗が小さくなって良好な接合界面が形成されるため、接合界面での元素の相互拡散が容易になり、母材鋼板と合せ材との接合性が確保される。
上記のクラッド圧延後、圧延板を加熱して焼きならしを行う。なお、ここでいう焼きならし温度は、圧延板の母材鋼板部分における板厚方向の板厚1/2位置の温度である。焼きならし温度がAc3変態点未満であると、オーステナイト変態が完了せず、最終組織が不均一となって母材鋼板の靱性が劣化する。一方、焼きならし温度が1000℃を超えると、オーステナイトのピンニングに作用するAlの窒化物やNbの炭窒化物の溶解により、オーステナイトが粗大化して母材鋼板の靱性が劣化する。従って、焼きならし温度はAc3変態点以上1000℃以下とする。好ましくは900℃~1000℃である。なお、Ac3変態点は、下記(1)式により求めることができる。
Ac3(℃)=912.0?230.5×C+31.6×Si?20.4×Mn?39.8×Cu?18.1×Ni?14.8×Cr+16.8×Mo…(1)
ここで、上記式(1)における元素記号は、各元素の含有量(質量%)を意味し、当該元素が含有されていない場合にはゼロとする。
最終組織のフェライトは、焼きならし時のオーステナイトの微細化によるフェライト変態核生成サイトの増加により微細化する。ここで、焼きならしの加熱時のオーステナイトの粒径は、焼きならし前組織の粒径と焼きならし時の析出物の分散状態が影響する。焼きならし前組織の微細化、析出物の量の増加およびサイズの低下をさせることにより、焼きならしの加熱時のオーステナイトは微細化する。上述のように、クラッド鋼板は合せ材と母材の接合性確保のために、高温での圧延が必要であり、母材の焼きならし前組織が、母材をクラッドではなく炭素鋼単独で製造する無垢材の組織に比べて粗大になり易い。そこで、焼きならしを2回以上実施することで、析出物の分散状態に顕著な変化はないが、焼きならし前組織が微細化することで最終組織のフェライトが微細化して母材靱性を確保することができる。従って、焼きならし回数は2回以上とする。各回の焼きならしの加熱時の温度の相互の関係については、特に制約されるものではなく、適宜選択してもよい。
Claims (8)
- 母材鋼板に合せ材が接合されているクラッド鋼板であって、
前記母材鋼板の成分組成は、質量%で、
C:0.120~0.180%、
Si:0.15~0.40%、
Mn:0.50~0.90%、
P:0.020%以下、
S:0.010%以下、
Mo:0.45~0.60%、
Nb:0.005~0.025%、
Al:0.005~0.050%、および
N:0.0010~0.0070%、
を含有し、さらに、Cu、Ni、Crを、
Cu+Ni+Cr:0.800~1.100%、
(ただし、各元素記号は各元素の含有量を示す。)
を満足する範囲で含有し、残部がFe及び不可避的不純物からなり、
前記母材鋼板の板厚方向の板厚1/2位置におけるベイナイトの面積率は20%以上であり、板厚方向の板厚1/2位置におけるフェライトの平均結晶粒径は15μm以下であるクラッド鋼板。 - 前記母材鋼板の成分組成が、さらに質量%で、
Cu:0.30~0.40%、
Ni:0.30~0.40%、
Cr:0.20~0.30%
を含有する請求項1に記載のクラッド鋼板。 - 前記母材鋼板の成分組成が、さらに質量%で、V:0.005~0.030%、Ti:0.005~0.030%、Ca:0.0005~0.0040%のうちから選ばれた1種または2種以上を含有する請求項1または2に記載のクラッド鋼板。
- 前記合せ材は、ステンレス鋼からなる請求項1~3のいずれか1項に記載のクラッド鋼板。
- 前記合せ材は、Ni基合金からなる請求項1~3のいずれか1項に記載のクラッド鋼板。
- 請求項1~3のいずれか1項に記載の母材鋼板の成分組成を有する母材鋼板の素材とステンレス鋼からなる合せ材の素材とを組み立てた組立スラブを、表面温度で1050℃~1200℃の温度域に加熱し、
加熱した前記組立スラブに表面温度950℃以上の温度域での圧下比1.5以上とする圧延を施して圧延板を作製し、
前記圧延板に、前記母材鋼板の板厚方向の板厚1/2位置の温度でAc3変態点以上1000℃以下の焼きならしを2回以上施す
クラッド鋼板の製造方法。 - 請求項1~3のいずれか1項に記載の母材鋼板の成分組成を有する母材鋼板の素材とNi基合金からなる合せ材の素材とを組み立てた組立スラブを、表面温度で1050℃~1200℃の温度域に加熱し、
加熱した前記組立スラブに表面温度950℃以上の温度域での圧下比2.0以上であって、圧延終了温度を前記組立スラブの表面温度800℃以上とする圧延を施して圧延板を作製し、
前記圧延板に、前記母材鋼板の板厚方向の板厚1/2位置の温度でAc3変態点以上1000℃以下の焼きならしを2回以上施す
クラッド鋼板の製造方法。 - 前記組立スラブを、母材鋼板の素材、合せ材の素材、合せ材の素材、母材鋼板の素材の順に積層して、または母材鋼板の素材と合せ材の素材とを積層して組み立てる請求項6または7に記載のクラッド鋼板の製造方法。
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CN108116006A (zh) * | 2016-11-30 | 2018-06-05 | 宝山钢铁股份有限公司 | 一种超级奥氏体不锈钢轧制复合钢板及其制造方法 |
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0475791A (ja) * | 1990-03-30 | 1992-03-10 | Nippon Steel Corp | クラッド鋼板の製造方法 |
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WO2018181381A1 (ja) * | 2017-03-29 | 2018-10-04 | Jfeスチール株式会社 | クラッド鋼板およびその製造方法 |
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---|
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