WO2019142559A1 - 高強度合金化電気亜鉛めっき鋼板およびその製造方法 - Google Patents
高強度合金化電気亜鉛めっき鋼板およびその製造方法 Download PDFInfo
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- WO2019142559A1 WO2019142559A1 PCT/JP2018/045856 JP2018045856W WO2019142559A1 WO 2019142559 A1 WO2019142559 A1 WO 2019142559A1 JP 2018045856 W JP2018045856 W JP 2018045856W WO 2019142559 A1 WO2019142559 A1 WO 2019142559A1
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- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 27
- 239000000203 mixture Substances 0.000 claims abstract description 21
- 239000011701 zinc Substances 0.000 claims abstract description 20
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 14
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000012535 impurity Substances 0.000 claims abstract description 8
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- 229910000859 α-Fe Inorganic materials 0.000 description 5
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
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- 238000005336 cracking Methods 0.000 description 4
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- 238000005097 cold rolling Methods 0.000 description 3
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- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 2
- XGCDBGRZEKYHNV-UHFFFAOYSA-N 1,1-bis(diphenylphosphino)methane Chemical compound C=1C=CC=CC=1P(C=1C=CC=CC=1)CP(C=1C=CC=CC=1)C1=CC=CC=C1 XGCDBGRZEKYHNV-UHFFFAOYSA-N 0.000 description 1
- 241000219307 Atriplex rosea Species 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 229910001297 Zn alloy Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
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- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
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Images
Classifications
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- 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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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B15/00—Layered products comprising a layer of metal
- B32B15/01—Layered products comprising a layer of metal all layers being exclusively metallic
- B32B15/013—Layered products comprising a layer of metal all layers being exclusively metallic one layer being formed of an iron alloy or steel, another layer being formed of a metal other than iron or aluminium
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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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/001—Heat treatment of ferrous alloys containing Ni
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- C—CHEMISTRY; METALLURGY
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- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/002—Heat treatment of ferrous alloys containing Cr
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- C—CHEMISTRY; METALLURGY
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- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/005—Heat treatment of ferrous alloys containing Mn
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- C—CHEMISTRY; METALLURGY
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- 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
- C21D6/00—Heat treatment of ferrous alloys
- C21D6/008—Heat treatment of ferrous alloys containing Si
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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
- C22C18/00—Alloys based on zinc
- C22C18/04—Alloys based on zinc with aluminium as the next major constituent
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- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
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- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
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- C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
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- C22C—ALLOYS
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- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
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- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/16—Ferrous alloys, e.g. steel alloys containing 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
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
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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
- C22C38/38—Ferrous alloys, e.g. steel alloys containing chromium with more than 1.5% by weight of 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
- C22C38/18—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
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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
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/34—Pretreatment of metallic surfaces to be electroplated
- C25D5/36—Pretreatment of metallic surfaces to be electroplated of iron or steel
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/48—After-treatment of electroplated surfaces
- C25D5/50—After-treatment of electroplated surfaces by heat-treatment
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D7/00—Electroplating characterised by the article coated
- C25D7/06—Wires; Strips; Foils
- C25D7/0614—Strips or foils
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/22—Electroplating: Baths therefor from solutions of zinc
Definitions
- the present invention is a high strength alloyed electrogalvanized steel sheet excellent in formability and delayed fracture resistance and having a beautiful surface appearance and good plating adhesion, which is suitable as a member used in industrial fields such as automobiles It relates to the manufacturing method.
- high-strength galvanized steel sheets for automobiles are manufactured by hot-dip galvanizing treatment. After being cooled, the steel sheet annealed in a reducing atmosphere is immersed in molten zinc and the surface is galvanized.
- Si, Mn and Cr added to improve the formability of the steel sheet form an oxide on the surface of the steel sheet during annealing, thereby deteriorating the wettability between the molten zinc and the steel sheet and causing non-plating. Furthermore, even when non-plating does not occur, there is a problem that the plating adhesion is deteriorated.
- the reducing atmosphere used for annealing is generally an atmosphere containing hydrogen, and hydrogen is taken into the steel sheet during annealing, and this hydrogen degrades the delayed fracture resistance. Furthermore, it also causes the deterioration of formability such as bending and hole expandability.
- Patent Document 1 proposes a method of suppressing hydrogen embrittlement by forming an internal oxide layer and a soft layer on the surface of a steel plate and utilizing the internal oxide layer as a hydrogen trap site. .
- the hot-rolling temperature is limited to 560 degrees C or less, and the method of suppressing non-plating is proposed by applying electrogalvanization.
- Patent Document 1 when a large amount of internal oxide is present, there arises a problem that the corrosion resistance is deteriorated even if it is a galvanized steel sheet. In addition, when the internal oxide is formed in the grain boundary, the grain boundary strength may be reduced, which may deteriorate the formability of the steel sheet.
- the formation of the steel sheet surface oxide is greatly affected by the steel sheet components and the annealing conditions, so when adding a large amount of Mn, the surface oxide that inhibits the plating adhesion is completely It can not be suppressed.
- the present invention has been made focusing on the above problems, and is a high-strength alloyed electrogalvanized steel sheet excellent in formability and delayed fracture resistance and excellent in surface appearance and plating adhesion. It aims at providing the manufacturing method.
- the term "high strength” as used herein refers to a tensile strength (TS) of 780 MPa or more.
- the amount of diffusible hydrogen in the steel sheet greatly affects the formability and the delayed fracture resistance, it is necessary to reduce the amount of hydrogen.
- the hydrogen taken into the steel sheet during annealing is released in the process after cooling, but because the release rate is slow, it is not released sufficiently before hot-dip galvanizing in the normal continuous hot-dip galvanizing process and remains in the steel sheet Do.
- the hydrogen concentration in the atmosphere greatly influences the hydrogen release, it was found that the hydrogen release is promoted when the hydrogen release is maintained after the annealing in a low hydrogen atmosphere.
- Component composition is, in mass%, C: 0.030% or more and 0.250% or less, Si: 0.01% or more and 3.00% or less, Mn: 1.00% or more and 10.00% or less, P: 0.001% or more and 0.100% or less, S: 0.0001% or more and 0.0200% or less, and the balance is Fe and unavoidable impurities,
- the surface has an alloyed electrogalvanized layer, Fe content in the galvanized layer is 8.0 to 15.0%, Tensile strength is 780MPa or more, The amount of diffusible hydrogen in the steel plate is 0.2 wt.
- High strength alloyed electrogalvanized steel sheet which is less than ppm.
- the component composition further contains, in mass%, at least one selected from N: 0.0005% to 0.0100% and Ti: 0.005% to 0.200%.
- the above-mentioned component composition is, further, in mass%, Al: 0.01% to 2.00%, Nb: 0.005% to 0.200%, B: 0.0003% to 0.0050.
- the component composition is, in mass%, C: 0.030% or more and 0.250% or less, Si: 0.01% or more and 3.00% or less, Mn: 1.00% or more and 10.00% or less, P In a steel plate containing 0.001% or more and 0.100% or less, S: 0.0001% or more and 0.0200% or less, with the balance being Fe and unavoidable impurities, A heat treatment step of holding for 20 s or more and 900 s or less in a temperature range of 600 ° C. or more and 950 ° C. or less in an atmosphere with an H 2 concentration of 1.0 vol% or more and 20.0 vol% or less and a dew point of 0 ° C.
- An electrogalvanization process step of electrogalvanizing A method for producing a high-strength alloyed electrogalvanized steel sheet having a tensile strength of 780 MPa or more, which is subjected to an alloying treatment step of subjecting to an alloying treatment.
- the component composition further contains, in mass%, at least one selected from N: 0.0005% to 0.0100% and Ti: 0.005% to 0.200%.
- the above-mentioned component composition is, further, in mass%, Al: 0.01% to 2.00%, Nb: 0.005% to 0.200%, B: 0.0003% to 0.0050. % Or less, Ni: 0.005% or more and 1.000% or less, Cr: 0.005% or more and 1.00% or less, V: 0.005% or more and 0.500% or less, Mo: 0.005% or more and 1 .000% or less, Cu: 0.005% or more and 1.000% or less, Sn: 0.002% or more and 0.200% or less, Sb: 0.005% or more and 0.100% or less, Ca: 0.0005% As described in [5] or [6], containing at least one of 0.0050% or less, Mg: 0.0005% or more and 0.0050% or less, and REM: 0.0005% or more and 0.0050% or less Of high strength alloyed electrogalvanized steel sheet.
- a high-strength alloyed electrogalvanized steel sheet excellent in formability and delayed fracture resistance having a TS of 780 MPa or more and excellent in surface appearance and plating adhesion can be obtained.
- FIG. 1 is a schematic view of a test piece for evaluating delayed fracture resistance evaluation characteristics in an example.
- FIG. 2 is explanatory drawing which shows the process of the combined cycle corrosion test in an Example.
- Component Composition The component composition of the high strength alloyed electrogalvanized steel sheet of the present invention and the reason for limitation will be described.
- “%” which is a unit of content of the following component composition shall mean “mass%” unless otherwise indicated.
- C 0.030% or more and 0.250% or less C is an element necessary for generating a low-temperature transformation phase such as martensite to increase the strength. In addition, it is an element effective for improving the stability of retained austenite and improving the ductility of steel. If the C content is less than 0.030%, it is difficult to secure a desired martensite area ratio, and a desired strength can not be obtained. In addition, it is difficult to secure a sufficient volume fraction of retained austenite, and good ductility can not be obtained. From such a viewpoint, the amount of C is set to 0.030% or more, preferably 0.050% or more, and more preferably 0.080% or more.
- the amount of C is set to 0.250% or less, preferably 0.200% or less, and more preferably 0.150% or less.
- Si 0.01% or more and 3.00% or less Si is effective for securing good ductility because it improves the work hardenability of ferrite. If the amount of Si is less than 0.01%, the effect is poor, so the lower limit is made 0.01%. Therefore, the amount of Si is 0.01% or more, preferably 0.20% or more, and more preferably 0.50% or more. On the other hand, excessive content of Si exceeding 3.00% not only causes embrittlement of the steel but also causes deterioration of the surface properties due to the occurrence of red scale and the like. Therefore, the amount of Si is therefore 3.00% or less, preferably 2.00% or less, and more preferably 1.80% or less.
- Mn 1.00% or more and 10.00% or less
- Mn is an element that stabilizes retained austenite, is effective for securing good ductility, and is an element that raises the strength of steel by solid solution strengthening. Such an effect is observed when the Mn content of the steel is 1.00% or more. Therefore, the Mn content is 1.00% or more, preferably 1.20% or more, and more preferably 2.30% or more. However, an excessive content in which the amount of Mn exceeds 10.00% causes a cost increase. Therefore, the Mn content is 10.00% or less, preferably 8.00% or less, more preferably 6.00% or less.
- P 0.001% or more and 0.100% or less
- P has an effect of solid solution strengthening, and is an element that can be added according to a desired strength. It is also an element effective for complex organization to promote ferrite transformation. In order to acquire such an effect, it is necessary to make P amount 0.001% or more. Therefore, the P amount is 0.001% or more, preferably 0.003% or more, and more preferably 0.005% or more.
- the P amount is 0.100% or less, preferably 0.050% or less, and more preferably 0.020% or less.
- S 0.0001% or more and 0.0200% or less S segregates in grain boundaries to embrittle the steel during hot working, and also exists as a sulfide to lower the local deformability. Therefore, the S amount needs to be 0.0200% or less. Therefore, the S content is 0.0200% or less, preferably 0.0100% or less, and more preferably 0.0050% or less. However, due to limitations in production technology, the amount of S needs to be at least 0.0001%. Therefore, the S content is at least 0.0001%, preferably at least 0.0003%, more preferably at least 0.0005%.
- the balance other than the above components consists of Fe and unavoidable impurities.
- the above components are the basic components of the present invention. In addition to the above components, at least one of the following elements may be contained.
- N 0.0005% or more and 0.0100% or less N is an element that degrades the aging resistance of the steel. In particular, when the N content exceeds 0.0100%, the deterioration of the aging resistance becomes remarkable. Therefore, when N is added, the N amount is 0.0100% or less, preferably 0.0070% or less, and more preferably 0.0050% or less. The smaller the amount of N, the better. However, in view of production technology limitations, the amount of N is preferably made 0.0005% or more. When N is added, the amount of N is more preferably 0.0010% or more, further preferably 0.0020% or more.
- Ti 0.005% or more and 0.200% or less
- Ti is effective for precipitation strengthening of steel and, in addition, forms a relatively hard ferrite to form a hard second phase (martensite or retained austenite) Hardness difference can be reduced and good stretch flangeability can also be secured. The effect is obtained at 0.005% or more. Therefore, when adding Ti, the amount of Ti is made 0.005% or more, preferably 0.010% or more, more preferably 0.015% or more. However, if the Ti content exceeds 0.200%, the area ratio of hard martensite becomes excessive, microvoids at grain boundaries of martensite increase, and further, propagation of cracks progresses, and forming Sex is reduced. Therefore, when adding Ti, the amount of Ti is 0.200% or less, preferably 0.150% or less, more preferably 0.100% or less.
- Al 0.01% or more and 2.00% or less
- Nb 0.005% or more and 0.200% or less
- B 0.0003% or more and 0.0050% or less
- Ni 0.005% or more and 1.000%
- Cr 0.005% or more and 1.00% or less
- V 0.005% or more and 0.500% or less
- Mo 0.005% or more and 1.000% or less
- Cu 0.005% or more.
- Al enlarges the two phase region of ferrite and austenite Low annealing temperature dependence , That is an element effective for the material stability. Moreover, it is an element which acts as a deoxidizer and is effective for the cleanliness of steel, and is preferably added in the deoxidation step. If the amount of Al is less than 0.01%, the addition effect becomes poor.
- the amount of Al when adding Al, is 0.01% or more, preferably 0.02% or more, and more preferably 0.03% or more. However, if it exceeds 2.00%, the risk of steel piece cracking during continuous casting increases, which lowers the manufacturability. From such a viewpoint, when adding Al, the amount of Al is 2.00% or less, preferably 1.20% or less, and more preferably 0.80% or less.
- Nb 0.005% or more and 0.200% or less Nb is effective for precipitation strengthening of steel, and its effect can be obtained at 0.005% or more, respectively. Also, similar to the effect of Ti addition, by forming relatively hard ferrite, the difference in hardness with the hard second phase (martensite or retained austenite) can be reduced, and good stretch flangeability can also be ensured. . The effect is obtained at 0.005% or more. Therefore, when Nb is added, the Nb content is made 0.005% or more, preferably 0.010% or more, more preferably 0.020% or more.
- the Nb amount is 0.200% or less, preferably 0.150% or less, and more preferably 0.100% or less.
- B 0.0003% or more and 0.0050% or less B has an action to suppress the formation and growth of ferrite from austenite grain boundaries, and since it is possible to control the structure flexibly, it is necessary to add it as necessary. Can. The effect is obtained at 0.0003% or more. Therefore, when B is added, the B content is made 0.0003% or more, preferably 0.0005% or more, more preferably 0.0010% or more. However, if it exceeds 0.0050%, the formability is reduced. Therefore, when B is added, the amount of B is made 0.0050% or less, preferably 0.0030% or less, more preferably 0.0040% or less.
- Ni 0.005% or more and 1.000% or less
- Ni is an element that stabilizes retained austenite, is effective in securing good ductility, and is an element that raises the strength of the steel by solid solution strengthening. The effect is obtained at 0.005% or more. Therefore, when adding Ni, the amount of Ni is 0.005% or more, preferably 0.008% or more, and more preferably 0.010% or more. On the other hand, if it exceeds 1.000%, hard martensite becomes excessive, microvoids at grain boundaries of martensite increase during bending test and hole expansion test, and further, propagation of cracks progresses. , Bendability and stretch flangeability decrease. In addition, it becomes a factor of cost increase. Therefore, when adding Ni, the amount of Ni is set to 1.000% or less, preferably 0.500% or less, more preferably 0.300% or less.
- Cr 0.005% or more and 1.00% or less, V: 0.005% or more and 0.500% or less, Mo: 0.005% or more and 1.000% or less Cr, V, and Mo have a balance of strength and ductility It can be added as necessary because it has the effect of improving The effect is obtained with Cr: 0.005% or more, V: 0.005% or more, Mo: 0.005 %% or more. Therefore, when adding these elements, Cr: 0.005% or more, V: 0.005% or more, Mo: 0.005% or more.
- Cr is preferably 0.010% or more, more preferably 0.050% or more
- V is preferably 0.008% or more, more preferably 0.010% or more
- Mo is Preferably, it is 0.010% or more, more preferably 0.050% or more.
- Cr: 1.00%, V: 0.500%, Mo: 1.000% hard martensite becomes excessive, microvoids at grain boundaries of martensite increase, and further The propagation of cracks progresses, and the formability decreases. In addition, it becomes a factor of cost increase. Therefore, when adding these elements, Cr: 1.00% or less, V: 0.500% or less, and Mo: 1.000% or less.
- Cr is preferably 0.08% or less, more preferably 0.05% or less
- V is preferably 0.300% or less, more preferably 0.100% or less
- Mo is Preferably it is 0.800% or less, more preferably 0.500% or less.
- Cu 0.005% or more and 1.000% or less
- Cu is an element effective for strengthening steel, and may be used for strengthening steel within the range specified in the present invention. The effect is obtained at 0.005% or more. Therefore, when adding Cu, the amount of Cu is made 0.005% or more, preferably 0.008% or more, more preferably 0.010% or more. On the other hand, if the Cu content exceeds 1.000%, hard martensite becomes excessive, microvoids at grain boundaries of martensite increase, and further, propagation of cracks progresses, and formability deteriorates Do. Therefore, when adding Cu, the amount of Cu is 1.000% or less, preferably 0.800% or less, more preferably 0.500% or less.
- Sn 0.002% or more and 0.200% or less
- Sb 0.005% or more and 0.100% or less
- Sn and Sb are decarburized in a region of several tens of ⁇ m of the surface layer of the steel sheet generated by nitriding or oxidation of the steel sheet surface From the viewpoint of suppressing By suppressing such nitriding and oxidation, it is possible to prevent the reduction of the area ratio of martensite on the surface of the steel plate, and it is effective to secure the strength and the material stability. Therefore, when adding Sn, the amount of Sn is set to 0.002% or more, preferably 0.005% or more, and more preferably 0.010% or more.
- the amount of Sb is 0.005% or more, preferably 0.008% or more, and more preferably 0.010% or more. On the other hand, if any of these elements is added in excess, toughness will be reduced. Therefore, when adding Sn, the amount of Sn is 0.200% or less, preferably 0.100% or less, and more preferably 0.060% or less. When Sb is added, the amount of Sb is 0.100% or less, preferably 0.050% or less, and more preferably 0.030% or less.
- Ca, Mg, and REM have a sulfide shape It is an element effective to improve the adverse effect of sulfides on spheroidizing and hole spreading (stretch flangeability). This effect is obtained at 0.0005% or more, respectively. Therefore, when adding Ca, Mg and REM, the addition amounts thereof are respectively made 0.0005% or more, preferably 0.0008% or more, more preferably 0.0010% or more. However, if each exceeds 0.0050%, it causes an increase in inclusions and the like and causes surface and internal defects and the like. Therefore, in the case of adding Ca, Mg and REM, the addition amounts thereof are respectively 0.0050% or less, preferably 0.0035% or less, more preferably 0.0025% or less.
- Plating adhesion amount 20 g / m 2 or more Plating adhesion amount is important to secure corrosion resistance. If the adhesion amount is less than 20 g / m 2, it is difficult to ensure corrosion resistance. There is no particular upper limit, but if it exceeds 120 g / m 2 , the peel resistance will deteriorate for automotive applications, so 120 g / m 2 or less is preferable.
- the plating coverage is more preferably 30 to 60 g / m 2 .
- the Fe content in zinc plating layer 8.0 to 15.0% When the plating is alloyed, the Fe--Zn alloy phase such as ⁇ phase, ⁇ phase and ⁇ phase is formed in the plating layer by the alloying. When the Fe content is less than 8.0%, ⁇ phase is formed on the plated surface. Since the cocoon phase is soft, it tends to flake off at the time of pressing. On the other hand, when the hard and brittle ⁇ phase is excessively formed, the plating adhesion is lowered. The decrease in the plating adhesion becomes remarkable when the Fe content in the plating layer is 15.0%. Therefore, the Fe content in the plating layer is set to 8.0% to 15.0%.
- the amount of diffusible hydrogen in the steel plate is 0.2 wt. Dppm or less Diffusible hydrogen in the steel plate causes delayed fracture of the steel plate, and the greater the amount of diffusible hydrogen, the more likely delayed fracture.
- the amount of diffusible hydrogen is 0.2 wt. If it exceeds ppm, cracking occurs in the delayed fracture resistance test described later. Therefore, the amount of diffusible hydrogen in the steel plate is 0.2 wt. Do not exceed ppm.
- the manufacturing method of the steel plate used as the raw material of the manufacturing method of the present invention is not particularly limited.
- a steel slab having the above-mentioned component composition is subjected to rough rolling and finish rolling after heating in a hot rolling step, and thereafter acid
- the method of cold-rolling after removing the scale of the hot-rolled sheet surface layer by a washing process is mentioned.
- the conditions of the hot rolling process, the conditions of the pickling process, and the conditions of the cold rolling process are not particularly limited, and the conditions may be set appropriately.
- the above-mentioned steel plate used as a raw material typically manufactures a steel material through each process such as steel making, casting, hot rolling etc. as described above, for example, one of hot rolling processes by thin casting etc. It may be manufactured omitting part or all.
- the steel sheet having the above-described component composition is subjected to a heat treatment including a heat treatment step and a holding step, and thereafter, a plating treatment (electro-zinc plating treatment step and an alloying treatment step) is performed.
- a plating treatment electro-zinc plating treatment step and an alloying treatment step
- Heat treatment process Holds 20 s or more and 900 s or less in a temperature range of 600 ° C. or more and 950 ° C. or less in an atmosphere with an H 2 concentration of 1.0 vol% or more and 20.0 vol% or less and a dew point of 0 ° C or less Make adjustments to get the desired material.
- H 2 is necessary to suppress Fe oxidation on the steel sheet surface during heat treatment.
- the H 2 concentration is less than 1.0 vol%, Fe on the surface of the steel sheet is oxidized to deteriorate the plating adhesion.
- the H 2 concentration exceeds 20.0 vol%, the amount of hydrogen intruding into the steel sheet increases, and it is not released in the later-described holding step, and the delayed fracture resistance is deteriorated. Therefore, the H 2 concentration is set to 1.0 vol% or more and 20.0 vol% or less.
- the atmospheric components other than H 2 are N 2 and unavoidable impurities.
- the dew point in the atmosphere exceeds 0 ° C.
- decarburization occurs in the surface layer of the steel sheet, and the strength of the surface layer of the steel sheet decreases.
- the lower limit of the dew point is not particularly defined, it is difficult to realize industrially at -60 ° C. or lower, and the cost is significantly increased. Therefore, the dew point is preferably higher than -60 ° C.
- the temperature range of the heat treatment is set to 600 ° C. or more and 950 ° C. or less.
- the holding time is set to 20 s or more and 900 s or less.
- Holding step After cooling the steel plate after the heat treatment step to 200 to 600 ° C., the steel plate is held for 30 seconds or more in a temperature range of 200 to 600 ° C. in an atmosphere of H 2 concentration less than 1.0% vol. To transform the austenite formed in the above into martensite, to obtain a desired strength, and to release hydrogen that has penetrated into the steel sheet.
- the cooling rate at the time of cooling the steel sheet after the heat treatment step to 200 to 600 ° C. is not particularly limited, and 10 ° C./s or more is preferable.
- the H 2 concentration is 1.0 vol% or more, the release of hydrogen is suppressed, and the delayed fracture resistance is degraded.
- the lower limit is not particularly defined, and an atmosphere which does not intentionally contain H 2 , that is, an atmosphere containing it as an unavoidable impurity may be used.
- the atmosphere components other than H 2 are not particularly limited, but in order to suppress excessive oxidation of the steel sheet surface, the O 2 concentration is preferably less than 0.01 vol% and the dew point is less than 0 ° C.
- the holding temperature is set to 200 to 600.degree. If the holding time is less than 30 s, hydrogen release from the steel sheet is not sufficiently performed, and the delayed fracture resistance is degraded. Therefore, the holding time is 30 s or more.
- the holding time is preferably 500 s or less. This is because if the holding time is long, the furnace length becomes long and productivity decreases.
- Electrogalvanizing treatment step The electrogalvanizing treatment is a step of cooling the steel plate subjected to the heat treatment step to form an electrogalvanized layer on the surface of the steel plate.
- the conditions for the electrogalvanization are not particularly limited, but the current density is preferably 30 to 1200 A / dm 2 .
- the pickling solution is not particularly limited, and any acid such as hydrochloric acid, sulfuric acid, nitric acid or the like is possible.
- the process of alloying treatment are not particularly limited, and may be performed in the same line immediately after electroplating.
- the alloying temperature is not particularly limited, and the alloying temperature and the alloying time are adjusted so that the Fe content is 8.0 to 15.0%.
- Al is added to suppress the alloying of Fe—Zn in the plating bath, but in galvanizing, it is not necessary. Therefore, Al is not contained in the plating layer manufactured by electrogalvanizing, or, when it is contained unavoidable, it is contained 0.01 mass% or less. Since the high strength alloyed electrogalvanized steel sheet according to the present invention is also manufactured by electrogalvanization, the Al content of the plating layer is zero or 0.01% by mass when it is contained unavoidable. Below, it is included.
- a steel having the component composition shown in Table 1 was melted in a converter and made into a slab by a continuous casting method.
- the obtained slab is hot-rolled, pickled, subjected to a cold-rolling step as required, and heat-treated and held under the conditions shown in Table 2-1, Table 2-2, Table 2-3 and Table 3.
- the process was carried out.
- an electrogalvanizing treatment step and an alloying treatment step were performed to obtain an alloyed electrogalvanized steel sheet.
- the electrogalvanization was performed in a zinc sulfate bath under the conditions of a current density of 100 A / dm 2 . Moreover, it pickled in 5% sulfuric acid before electrogalvanization.
- the obtained steel plate it investigated about the tensile property, the hole expansibility, the formability, the delayed fracture characteristic, the surface appearance, and the plating adhesion.
- ⁇ Tensile characteristics> The tensile test is performed according to JIS Z 2241 (2011) using a JIS No. 5 test piece obtained by taking a sample so that the tensile direction is perpendicular to the rolling direction of the steel plate, and TS (tensile strength), EL (Total elongation) was measured.
- TS tensile strength
- EL Total elongation
- Test pieces having a width of 35 mm and a length of 100 mm were produced by grinding, and were bent at 180 ° with a radius of curvature of 4 mm to form bent test pieces.
- the bending test piece 1 was restrained by a bolt 2 and a nut 3 so that the inner space was 8 mm as shown in FIG. 1, and the shape of the test piece was fixed to obtain a test piece for evaluating delayed fracture resistance evaluation characteristics.
- delayed fracture resistance evaluation test was conducted in parallel under the conditions of saltwater immersion closer to the real environment.
- hydrochloric acid immersion test hydrochloric acid having a concentration of 5 wt% and a specific liquid volume of 60 ml / cm 2 was used.
- the test piece was immersed in this hydrochloric acid, and when it did not occur for a crack of 1 mm or more in length after immersion for 96 hours, the delayed fracture resistance was regarded as good ( ⁇ ), and when the crack occurred, it was rejected ( ⁇ ).
- the saltwater immersion test was performed as follows.
- a combined cycle corrosion test (see FIG. 2) consisting of the steps of drying, wetting and immersion in water, as defined in SAE J2334 defined by the American Automobile Technology Association, was conducted for up to 40 cycles.
- the occurrence of cracking was visually examined to determine the cracking occurrence cycle.
- this test was conducted for each 3 steel plates, and the average value was used for evaluation. The evaluation was made on the basis of the number of cycles according to the following criteria, and 30 cycles or more were regarded as good in delayed fracture resistance.
- the amount of diffusible hydrogen in the steel plate was measured as follows. First, zinc on the surface of the steel plate was removed by mechanical polishing. At this time, polishing was performed in liquid nitrogen so that the temperature of the steel plate did not rise. The obtained test piece was heated up to 250 ° C. at a heating rate of 100 ° C./s in an Ar atmosphere, and the released H 2 gas was quantitatively measured by gas chromatography.
- ⁇ Plating adhesion> Apply cellophane tape to the plating surface, bend and bend back the tape surface at 90 ° C, press the cellophane tape with a width of 24 mm parallel to the bent part against the inside of the processed part (compression side) and pull it apart
- the amount of peeling around a unit length (1 m) attached to a portion with a length of 40 mm was measured by a fluorescent X-ray method as a Zn count number, and was evaluated in light of the following criteria.
- the mask diameter was 30 mm
- the acceleration voltage of fluorescent X-ray was 50 kV
- the acceleration current was 50 mA
- the measurement time was 20 seconds
- ⁇ and ⁇ were accepted.
- Corrosion resistance was evaluated by the SST test. After subjecting the sample to chemical conversion treatment and electrodeposition coating, the sample surface was scored and a SST test was performed. Evaluation of corrosion resistance was made by comparing the swelling width around the cutting edge after the SST test with the comparison material, mild steel. In the evaluation, ⁇ and ⁇ are acceptable levels. :: Bulge width equal to that of mild steel ⁇ : Bulge width not more than 1.5 times that of mild steel ⁇ : Bulge width more than 1.5 times that of mild steel Results: Table 2-1, Table 2-2, Table 2-3 and Table It is shown in 3.
- the high strength steel plate of the present invention example is a high strength alloyed electrogalvanized steel plate excellent in formability and delayed fracture resistance having a TS of 780 MPa or more and excellent in surface appearance and plating adhesion.
- TS 780 MPa
- one of the characteristics is inferior.
- TS tensile strength
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Abstract
Description
[1]成分組成は、質量%で、C:0.030%以上0.250%以下、Si:0.01%以上3.00%以下、Mn:1.00%以上10.00%以下、P:0.001%以上0.100%以下、S:0.0001%以上0.0200%以下を含有し、残部がFeおよび不可避的不純物からなり、
表面には合金化電気亜鉛めっき層を有し、
亜鉛めっき層中のFe含有率が8.0~15.0%であり、
引張強度が780MPa以上であり、
鋼板中の拡散性水素量が0.2wt.ppm以下である、高強度合金化電気亜鉛めっき鋼板。
[2]前記亜鉛めっき層のめっき付着量が20g/m2以上である、[1]に記載の高強度合金化電気亜鉛めっき鋼板。
[3]前記成分組成は、さらに、質量%で、N:0.0005%以上0.0100%以下、Ti:0.005%以上0.200%以下のうちから選ばれる少なくとも1種を含有する、[1]または[2]に記載の高強度合金化電気亜鉛めっき鋼板。
[4]前記成分組成は、さらに、質量%で、Al:0.01%以上2.00%以下、Nb:0.005%以上0.200%以下、B:0.0003%以上0.0050%以下、Ni:0.005%以上1.000%以下、Cr:0.005%以上1.00%以下、V:0.005%以上0.500%以下、Mo:0.005%以上1.000%以下、Cu:0.005%以上1.000%以下、Sn:0.002%以上0.200%以下、Sb:0.005%以上0.100%以下、Ca:0.0005%以上0.0050%以下、Mg:0.0005%以上0.0050%以下、REM:0.0005%以上0.0050%以下のうちから選ばれる少なくとも1種を含有する、[1]から[3]のいずれかに記載の高強度合金化電気亜鉛めっき鋼板。
[5]成分組成は、質量%でC:0.030%以上0.250%以下、Si:0.01%以上3.00%以下、Mn:1.00%以上10.00%以下、P:0.001%以上0.100%以下、S:0.0001%以上0.0200%以下を含有し、残部がFeおよび不可避的不純物からなる鋼板に、
H2濃度が1.0vol%以上20.0vol%以下、露点が0℃以下の雰囲気中で、600℃以上950℃以下の温度域で20s以上900s以下保持する熱処理工程と、
前記熱処理工程後の鋼板を200~600℃に冷却後、H2濃度が1.0%vol未満の雰囲気中で200~600℃の温度域で30s以上保持する保持工程と、
電気亜鉛めっきを施す電気亜鉛めっき処理工程と、
合金化処理を施す合金化処理工程と
を施す、引張強度が780MPa以上である、高強度合金化電気亜鉛めっき鋼板の製造方法。
[6]前記成分組成は、さらに、質量%で、N:0.0005%以上0.0100%以下、Ti:0.005%以上0.200%以下のうちから選ばれる少なくとも1種を含有する、[5]に記載の高強度合金化電気亜鉛めっき鋼板の製造方法。
[7]前記成分組成は、さらに、質量%で、Al:0.01%以上2.00%以下、Nb:0.005%以上0.200%以下、B:0.0003%以上0.0050%以下、Ni:0.005%以上1.000%以下、Cr:0.005%以上1.00%以下、V:0.005%以上0.500%以下、Mo:0.005%以上1.000%以下、Cu:0.005%以上1.000%以下、Sn:0.002%以上0.200%以下、Sb:0.005%以上0.100%以下、Ca:0.0005%以上0.0050%以下、Mg:0.0005%以上0.0050%以下、REM:0.0005%以上0.0050%以下のうち少なくとも1種を含有する、[5]または[6]に記載の高強度合金化電気亜鉛めっき鋼板の製造方法。
本発明の高強度合金化電気亜鉛めっき鋼板の成分組成と、その限定理由について説明する。なお、以下の成分組成の含有量の単位である「%」は、特に断らない限り「質量%」を意味するものとする。
Cは、マルテンサイトなどの低温変態相を生成させて、強度を上昇させるために必要な元素である。また、残留オーステナイトの安定性を向上させ、鋼の延性を向上させるのに有効な元素である。C量が0.030%未満では所望のマルテンサイトの面積率を確保することが難しく、所望の強度が得られない。また、十分な残留オーステナイトの体積率を確保することが難しく、良好な延性が得られない。こうした観点から、C量は0.030%以上とし、好ましくは0.050%以上、より好ましくは0.080%以上である。また、一方、Cを、0.250%を超えて過剰に含有させると、硬質なマルテンサイトの面積率が過大となり、曲げ試験および穴広げ試験時に、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、曲げ性や伸びフランジ性が低下する。また、溶接部および熱影響部の硬化が著しく、溶接部の機械的特性が低下するため、スポット溶接性、アーク溶接性などが劣化する。こうした観点から、C量は0.250%以下とし、好ましくは0.200%以下、より好ましくは0.150%以下である。
Siは、フェライトの加工硬化能を向上させるため、良好な延性の確保に有効である。Si量が0.01%に満たないと、その効果が乏しくなるため、下限を0.01%とする。したがって、Si量は0.01%以上とし、好ましくは0.20%以上、より好ましくは0.50%以上である。一方、3.00%を超えるSiの過剰な含有は、鋼の脆化を引き起こすばかりか赤スケールなどの発生による表面性状の劣化を引き起こす。したがって、したがって、Si量は3.00%以下とし、好ましくは2.00%以下、より好ましくは1.80%以下である。
Mnは、残留オーステナイトを安定化させる元素で、良好な延性の確保に有効であり、さらに、固溶強化により鋼の強度を上昇させる元素である。このような作用は、鋼のMn量が1.00%以上で認められる。したがって、Mn量は1.00%以上とし、好ましくは1.20%以上であり、より好ましくは2.30%以上である。ただし、Mn量が10.00%を超える過剰な含有は、コストアップの要因になる。したがって、Mn量は10.00%以下とし、好ましくは8.00%以下、より好ましくは6.00%以下である。
Pは、固溶強化の作用を有し、所望の強度に応じて添加できる元素である。また、フェライト変態を促進するために複合組織化にも有効な元素である。こうした効果を得るためには、P量を0.001%以上にする必要がある。したがって、P量は0.001%以上とし、好ましくは0.003%以上、より好ましくは0.005%以上とする。一方、P量が0.100%を超えると、溶接性の劣化を招くとともに、亜鉛めっきを合金化処理する場合には、合金化速度を低下させ、亜鉛めっきの品質を損なう。したがって、P量は0.100%以下とし、好ましくは0.050%以下、より好ましくは0.020%以下とする。
Sは、粒界に偏析して熱間加工時に鋼を脆化させるとともに、硫化物として存在して局部変形能を低下させる。そのため、S量は0.0200%以下とする必要がある。したがって、S量は0.0200%以下とし、好ましくは0.0100%以下、より好ましくは0.0050%以下とする。しかし、生産技術上の制約から、S量は0.0001%以上にする必要がある。したがって、S量は0.0001%以上とし、好ましくは0.0003%以上、より好ましくは0.0005%以上である。
Nは、鋼の耐時効性を劣化させる元素である。特に、N量が0.0100%を超えると、耐時効性の劣化が顕著となる。したがって、Nを添加する場合、N量は0.0100%以下とし、好ましくは0.0070%以下、より好ましくは0.0050%以下とする。N量は少ないほど好ましいが、生産技術上の制約から、N量は0.0005%以上にすることが好ましい。Nを添加する場合、N量は、より好ましくは0.0010%以上、さらに好ましくは0.0020%以上とする。
Tiは、鋼の析出強化に有効であり、加えて、比較的硬質なフェライトを形成することにより、硬質第2相(マルテンサイトもしくは残留オーステナイト)との硬度差を低減でき、良好な伸びフランジ性も確保可能である。その効果は0.005%以上で得られる。したがって、Tiを添加する場合、Ti量は0.005%以上とし、好ましくは0.010%以上、より好ましくは0.015%以上とする。しかし、Ti量が0.200%を超えると、硬質なマルテンサイトの面積率が過大となり、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、成形性が低下する。したがって、Tiを添加する場合、Ti量は0.200%以下とし、好ましくは0.150%以下、より好ましくは0.100%以下とする。
Al:0.01%以上2.00%以下
Alは、フェライトとオーステナイトの二相域を拡大させ、焼鈍温度依存性の低減、つまり、材質安定性に有効な元素である。また、脱酸剤として作用し、鋼の清浄度に有効な元素であり、脱酸工程で添加することが好ましい。Al量が0.01%に満たないとその添加効果に乏しくなる。こうした観点から、Alを添加する場合、Al量は0.01%以上とし、好ましくは0.02%以上、より好ましくは0.03%以上である。しかし、2.00%を超えると、連続鋳造時の鋼片割れ発生の危険性が高まり、製造性を低下させる。こうした観点から、Alを添加する場合、Al量を2.00%以下とし、好ましくは1.20%以下、より好ましくは0.80%以下である。
Nbは、鋼の析出強化に有効で、その効果はそれぞれ0.005%以上で得られる。また、Ti添加の効果と同様に、比較的硬質なフェライトを形成することにより、硬質第2相(マルテンサイトもしくは残留オーステナイト)との硬度差を低減でき、良好な伸びフランジ性も確保可能である。その効果は0.005%以上で得られる。したがって、Nbを添加する場合、Nb量は0.005%以上とし、好ましくは0.010%以上、より好ましくは0.020%以上とする。しかし、0.200%を超えると、硬質なマルテンサイトの面積率が過大となり、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、成形性が低下する。また、コストアップの要因にもなる。したがって、Nbを添加する場合、Nb量は0.200%以下とし、好ましくは0.150%以下、より好ましくは0.100%以下とする。
Bは、オーステナイト粒界からのフェライトの生成および成長を抑制する作用を有し、臨機応変な組織制御が可能なため、必要に応じて添加することができる。その効果は、0.0003%以上で得られる。したがって、Bを添加する場合、B量は0.0003%以上とし、好ましくは0.0005%以上、より好ましくは0.0010%以上とする。しかし、0.0050%を超えると成形性が低下する。したがって、Bを添加する場合、B量は0.0050%以下とし、好ましくは0.0030%以下、より好ましくは0.0040%以下とする。
Niは、残留オーステナイトを安定化させる元素で、良好な延性の確保に有効であり、さらに、固溶強化により鋼の強度を上昇させる元素である。その効果は、0.005%以上で得られる。したがって、Niを添加する場合、Ni量は0.005%以上とし、好ましくは0.008%以上、より好ましくは0.010%以上である。一方、1.000%を超えると、硬質なマルテンサイトが過大となり、曲げ試験および穴広げ試験時に、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、曲げ性や伸びフランジ性が低下する。また、コストアップの要因にもなる。したがって、Niを添加する場合、Ni量は1.000%以下とし、好ましくは0.500%以下、より好ましくは0.300%以下とする。
Cr、V、Moは、強度と延性のバランスを向上させる作用を有するので必要に応じて添加することができる。その効果は、Cr:0.005%以上、V:0.005%以上、Mo:0.005%%以上で得られる。したがって、これらの元素を添加する場合、それぞれCr:0.005%以上、V:0.005%以上、Mo:0.005%以上とする。これらの元素を添加する場合、それぞれ、Crは好ましくは0.010%以上、より好ましくは0.050%以上、Vは好ましくは0.008%以上、より好ましくは0.010%以上、Moは好ましくは0.010%以上、より好ましくは0.050%以上とする。しかしながら、それぞれCr:1.00%、V:0.500%、Mo:1.000%を超えると、硬質なマルテンサイトが過大となり、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、成形性が低下する。また、コストアップの要因にもなる。したがって、これらの元素を添加する場合、それぞれCr:1.00%以下、V:0.500%以下、Mo:1.000%以下とする。これらの元素を添加する場合、それぞれ、Crは好ましくは0.08%以下、より好ましくは0.05%以下、Vは好ましくは0.300%以下、より好ましくは0.100%以下、Moは好ましくは0.800%以下、より好ましくは0.500%以下とする。
Cuは、鋼の強化に有効な元素であり、本発明で規定した範囲内であれば鋼の強化に使用して差し支えない。その効果は、0.005%以上で得られる。したがって、Cuを添加する場合には、Cu量は0.005%以上とし、好ましくは0.008%以上、より好ましくは0.010%以上である。一方、Cu量が1.000%を超えると、硬質なマルテンサイトが過大となり、マルテンサイトの結晶粒界でのマイクロボイドが増加し、さらに、亀裂の伝播が進行してしまい、成形性が低下する。したがって、Cuを添加する場合には、Cu量は1.000%以下とし、好ましくは0.800%以下、より好ましくは0.500%以下である。
SnおよびSbは、鋼板表面の窒化や酸化によって生じる鋼板表層の数十μm程度の領域の脱炭を抑制する観点から、必要に応じて添加する。このような窒化や酸化を抑制することによれば、鋼板表面においてマルテンサイトの面積率が減少するのを防止し、強度や材質安定性の確保に有効である。したがって、Snを添加する場合、Sn量は0.002%以上とし、好ましくは0.005%以上、より好ましくは0.010%以上である。また、Sbを添加する場合、Sb量は0.005%以上とし、好ましくは0.008%以上、より好ましくは0.010%以上である。一方で、これらいずれの元素についても、過剰に添加すると靭性の低下を招く。したがって、Snを添加する場合、Sn量は0.200%以下とし、好ましくは0.100%以下、より好ましくは0.060%以下である。また、Sbを添加する場合、Sb量は0.100%以下とし、好ましくは0.050%以下、より好ましくは0.030%以下である。
Ca、MgおよびREMは、硫化物の形状を球状化し、穴広げ性(伸びフランジ性)への硫化物の悪影響を改善するために有効な元素である。この効果は、それぞれ0.0005%以上で得られる。したがって、Ca、MgおよびREMを添加する場合は、その添加量はそれぞれ0.0005%以上とし、好ましくは0.0008%以上、より好ましくは0.0010%以上である。しかしながら、それぞれ0.0050%を超えると、介在物等の増加を引き起こし表面および内部欠陥などを引き起こす。したがって、Ca、MgおよびREMを添加する場合は、その添加量はそれぞれ0.0050%以下とし、好ましくは0.0035%以下、より好ましくは0.0025%以下である。
次に、鋼板表面の合金化電気亜鉛めっき層の組成について説明する。
めっき付着量は耐食性を担保するために重要である。付着量が20g/m2未満では耐食性確保が困難である。上限は特に設けないが、120g/m2を超えると自動車用途としては耐剥離性が劣化するため、120g/m2以下が好ましい。めっき付着量は、より好ましくは、30~60g/m2である。
めっきに合金化を施す場合、合金化によりめっき層中にζ相、δ相、Γ相といったFe-Zn合金相が形成される。Fe含有率が8.0%未満の場合、めっき表面にζ相が形成される。ζ相は柔らかいためプレス時に鱗片状に剥離しやすい。一方で、硬くて脆いΓ相が過剰に形成されると、めっき密着性が低下する。このめっき密着性の低下はめっき層中のFe含有率が15.0%で顕著となる。このため、めっき層中のFe含有率は8.0%~15.0%とする。
鋼板中の拡散性水素は鋼板の遅れ破壊の原因となり、拡散性水素量が多いほど遅れ破壊しやすくなる。拡散性水素量が0.2wt.ppmを超えると、後述の耐遅れ破壊特性試験において、割れが発生する。このため、鋼板中の拡散性水素量は0.2wt.ppm以下とする。
次に、本発明の製造方法について説明する。
熱処理工程は、鋼板組織を調整し、目的の材質を得るために行なう。
保持工程は、熱処理工程で形成したオーステナイトをマルテンサイトに変態させ、所望の強度を得るため、および鋼板内に侵入した水素を放出するために行う。
電気亜鉛めっき処理は、熱処理工程を施した鋼板を冷却し、鋼板表面に電気亜鉛めっき層を形成する工程である。電気亜鉛めっきの条件は特に定めないが、電流密度は、30~1200A/dm2であることが好ましい。また、保持工程で表面に形成した酸化物を除去するため、電気亜鉛めっき前に酸洗することが好ましい。また、酸化物を完全に除去する必要はないため、酸洗溶液は特に定めず、塩酸、硫酸、硝酸等いずれの酸でも可能である。
合金化処理の条件は特に限定されず、電気めっき直後に同一ラインで行っても良い。同一ラインで行う場合には、生産性を考慮して合金化温度450℃以上で行うのが好ましい。これは、合金化温度が450℃未満であると、合金化速度が遅く、合金化処理のためのライン長が長くなるためである。一方、別ラインで行う場合には合金化処理温度は特に限定されず、Fe含有率が8.0~15.0%となるように、合金化温度および合金化時間を調整する。
引張試験は、引張方向が鋼板の圧延方向と直角方向となるようにサンプルを採取したJIS5号試験片を用いて、JIS Z 2241(2011年)に準拠して行い、TS(引張強度)、EL(全伸び)を測定した。引張特性は、TS780MPa級ではEL≧18%、TS980MPa級ではEL≧12%、TS1180MPa級以上ではEL≧7%の場合を良好と判断した。
穴広げ性(伸びフランジ性)は、日本鉄鋼連盟規格JFST1001に準拠して行った。得られた各鋼板を100mm×100mmに切断後、板厚2.0mm以上はクリアランス12%±1%で、板厚2.0mm未満はクリアランス12%±2%で、直径10mmの穴を打ち抜いた後、内径75mmのダイスを用いてしわ押さえ力9tonで抑えた状態で、60°円錐のポンチを穴に押し込んで亀裂発生限界における穴直径を測定し、下記の式から限界穴広げ率λ(%)を求め、この限界穴広げ率λの値から伸びフランジ性を評価した。λ≧25(%)の場合を良好と判定した。
λ(%)={(Df-D0)/D0}×100
ただし、Dfは亀裂発生時の穴径(mm)、D0は初期穴径(mm)である。
成形性は、EL(全延び)と穴広げ性で評価した。ELと穴広げ性が両方良好である場合を合格(○)、いずれかが劣る場合を不合格(×)とした。
研削加工により幅35mm×長さ100mmの試験片を作製し、曲率半径4mmRで180°曲げ加工して曲げ試験片とした。この曲げ試験片1を、図1に示すように内側間隔が8mmとなるようにボルト2とナット3で拘束して試験片形状を固定し、耐遅れ破壊評価特性評価用試験片を得た。
○:30サイクル以上または40サイクルで割れなし
△:10サイクル以上30サイクル未満で割れ発生
×:10サイクル未満で割れ発生
<拡散性水素量>
鋼板中の拡散性水素量は以下のように測定した。まず、鋼板表層の亜鉛を機械研磨により除去した。この時、鋼板の温度が上昇しないように、液体窒素中で研磨作業を行った。得られた試験片をAr雰囲気中で100℃/sの昇温速度で250℃まで昇温し、放出されたH2ガスをガスクロマトグラフィーで定量測定した。
不めっきやピンホールなどの外観不良の有無を目視にて判断し、外観不良がない場合には良好(○)、外観不良がある場合には(×)と判定した。
めっき表面にセロハンテープを貼り、テープ面を90℃曲げおよび曲げ戻しをし、加工部の内側(圧縮加工側)に、曲げ加工部と平行に巾24mmのセロハンテープを押し当てて引き離し、セロハンテープの長さ40mmの部分に付いた単位長さ(1m)辺りの剥離量を、Znカウント数として蛍光X線法により測定し、下記基準に照らして評価した。なお、この時のマスク径は30mm、蛍光X線の加速電圧は50kV、加速電流は50mA、測定時間は20秒であり、◎および○を合格とした。
◎:Znカウント数3000未満
○:Znカウント数3000以上~5000未満
△:Znカウント数5000以上~10000未満
×:Znカウント数10000以上
<耐食性>
耐食性はSST試験で評価した。サンプルに化成処理および電着塗装を施した後、サンプル表面に切り込み疵を入れ、SST試験を行った。SST試験後の切り込み疵周辺の膨れ幅を比較材の軟鋼と比較し、耐食性の評価を行った。評価は◎と○が合格レベルである。
◎:膨れ幅が軟鋼と同等
○:膨れ幅が軟鋼の1.5倍以下
×:膨れ幅が軟鋼の1.5倍超
結果を表2-1、表2-2、表2-3および表3に示す。
2 ボルト
3 ナット
Claims (7)
- 成分組成は、質量%で、
C:0.030%以上0.250%以下、
Si:0.01%以上3.00%以下、
Mn:1.00%以上10.00%以下、
P:0.001%以上0.100%以下、
S:0.0001%以上0.0200%以下を含有し、
残部がFeおよび不可避的不純物からなり、
表面には合金化電気亜鉛めっき層を有し、
亜鉛めっき層中のFe含有率が8.0~15.0%であり、
引張強度が780MPa以上であり、
鋼板中の拡散性水素量が0.2wt.ppm以下である、高強度合金化電気亜鉛めっき鋼板。 - 前記亜鉛めっき層のめっき付着量が20g/m2以上である、請求項1に記載の高強度合金化電気亜鉛めっき鋼板。
- 前記成分組成は、さらに、質量%で、
N:0.0005%以上0.0100%以下、
Ti:0.005%以上0.200%以下のうちから選ばれる少なくとも1種を含有する、請求項1または2に記載の高強度合金化電気亜鉛めっき鋼板。 - 前記成分組成は、さらに、質量%で、
Al:0.01%以上2.00%以下、
Nb:0.005%以上0.200%以下、
B:0.0003%以上0.0050%以下、
Ni:0.005%以上1.000%以下、
Cr:0.005%以上1.00%以下、
V:0.005%以上0.500%以下、
Mo:0.005%以上1.000%以下、
Cu:0.005%以上1.000%以下、
Sn:0.002%以上0.200%以下、
Sb:0.005%以上0.100%以下、
Ca:0.0005%以上0.0050%以下、
Mg:0.0005%以上0.0050%以下、
REM:0.0005%以上0.0050%以下のうちから選ばれる少なくとも1種を含有する、請求項1から3のいずれかに記載の高強度合金化電気亜鉛めっき鋼板。 - 成分組成は、質量%で
C:0.030%以上0.250%以下、
Si:0.01%以上3.00%以下、
Mn:1.00%以上10.00%以下、
P:0.001%以上0.100%以下、
S:0.0001%以上0.0200%以下を含有し、残部がFeおよび不可避的不純物からなる鋼板に、
H2濃度が1.0vol%以上20.0vol%以下、露点が0℃以下の雰囲気中で、600℃以上950℃以下の温度域で20s以上900s以下保持する熱処理工程と、
前記熱処理工程後の鋼板を200~600℃に冷却後、H2濃度が1.0%vol未満の雰囲気中で200~600℃の温度域で30s以上保持する保持工程と、
電気亜鉛めっきを施す電気亜鉛めっき処理工程と、
合金化処理を施す合金化処理工程と
を施す、引張強度が780MPa以上である、高強度合金化電気亜鉛めっき鋼板の製造方法。 - 前記成分組成は、さらに、質量%で、
N:0.0005%以上0.0100%以下、
Ti:0.005%以上0.200%以下のうちから選ばれる少なくとも1種を含有する、請求項5に記載の高強度合金化電気亜鉛めっき鋼板の製造方法。 - 前記成分組成は、さらに、質量%で、
Al:0.01%以上2.00%以下、
Nb:0.005%以上0.200%以下、
B:0.0003%以上0.0050%以下、
Ni:0.005%以上1.000%以下、
Cr:0.005%以上1.00%以下、
V:0.005%以上0.500%以下、
Mo:0.005%以上1.000%以下、
Cu:0.005%以上1.000%以下、
Sn:0.002%以上0.200%以下、
Sb:0.005%以上0.100%以下、
Ca:0.0005%以上0.0050%以下、
Mg:0.0005%以上0.0050%以下、
REM:0.0005%以上0.0050%以下のうち少なくとも1種を含有する、請求項5または6に記載の高強度合金化電気亜鉛めっき鋼板の製造方法。
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Publication number | Priority date | Publication date | Assignee | Title |
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Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS609895A (ja) * | 1983-06-27 | 1985-01-18 | Sumitomo Metal Ind Ltd | 合金化電気亜鉛メツキ鋼板の製造方法 |
JPH0633213A (ja) * | 1992-07-17 | 1994-02-08 | Kobe Steel Ltd | 水素脆化の発生しない超高強度亜鉛めっき鋼板 |
JP2001262271A (ja) | 2000-03-17 | 2001-09-26 | Sumitomo Metal Ind Ltd | 電気めっき密着性および延性に優れた高張力鋼板およびその製造方法 |
JP2009035793A (ja) * | 2007-08-03 | 2009-02-19 | Sumitomo Metal Ind Ltd | 熱間プレス鋼板部材の製造方法 |
WO2014132637A1 (ja) * | 2013-02-28 | 2014-09-04 | Jfeスチール株式会社 | 高強度冷延鋼板の製造方法 |
WO2014199923A1 (ja) * | 2013-06-11 | 2014-12-18 | 新日鐵住金株式会社 | ホットスタンプ成形体およびホットスタンプ成形体の製造方法 |
JP2015089946A (ja) * | 2013-11-05 | 2015-05-11 | Jfeスチール株式会社 | 化成処理性および塗装後耐食性に優れた高強度冷延鋼板の製造方法 |
JP2016130358A (ja) | 2015-01-09 | 2016-07-21 | 株式会社神戸製鋼所 | 高強度めっき鋼板、並びにその製造方法 |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5015341A (en) * | 1988-08-05 | 1991-05-14 | Armco Steel Company, L.P. | Induction galvannealed electroplated steel strip |
JP4500124B2 (ja) * | 2004-07-23 | 2010-07-14 | 新日本製鐵株式会社 | ホットプレス用めっき鋼板の製造方法 |
KR101402503B1 (ko) * | 2009-08-31 | 2014-06-03 | 신닛테츠스미킨 카부시키카이샤 | 고강도 용융 아연 도금 강판 및 그 제조 방법 |
JP5370104B2 (ja) * | 2009-11-30 | 2013-12-18 | 新日鐵住金株式会社 | 耐水素脆化特性に優れた引張最大強度900MPa以上の高強度鋼板および高強度冷延鋼板の製造方法、高強度亜鉛めっき鋼板の製造方法 |
JP5906753B2 (ja) * | 2011-02-24 | 2016-04-20 | Jfeスチール株式会社 | 合金化溶融亜鉛めっき鋼板 |
KR101824823B1 (ko) * | 2013-08-26 | 2018-02-01 | 제이에프이 스틸 가부시키가이샤 | 고강도 용융 아연 도금 강판의 제조 방법 |
JP6052145B2 (ja) * | 2013-11-28 | 2016-12-27 | Jfeスチール株式会社 | 焼付け硬化型溶融亜鉛めっき鋼板 |
EP3159420B1 (en) * | 2014-09-08 | 2020-09-16 | JFE Steel Corporation | Method for producing high-strength hot-dipped galvanized steel sheet |
EP3214193B1 (en) * | 2014-10-30 | 2019-03-06 | JFE Steel Corporation | High-strength steel sheet, high-strength hot-dip galvanized steel sheet, high-strength hot-dip aluminum-coated steel sheet, and high-strength electrogalvanized steel sheet, and methods for manufacturing same |
KR101657796B1 (ko) * | 2014-12-15 | 2016-09-20 | 주식회사 포스코 | 내지연파괴 특성이 우수한 고강도 강판 및 이의 제조방법 |
CN107148488B (zh) * | 2015-01-07 | 2020-02-07 | Posco公司 | 拉伸强度为1300Mpa以上的超高强度镀覆钢板及其制造方法 |
DE102015111177A1 (de) * | 2015-07-10 | 2017-01-12 | Salzgitter Flachstahl Gmbh | Höchstfester Mehrphasenstahl und Verfahren zur Herstellung eines kaltgewalzten Stahlbandes hieraus |
JP6249113B2 (ja) * | 2016-01-27 | 2017-12-20 | Jfeスチール株式会社 | 高降伏比型高強度亜鉛めっき鋼板及びその製造方法 |
JP6524977B2 (ja) * | 2016-07-05 | 2019-06-05 | Jfeスチール株式会社 | 高強度鋼板およびその製造方法 |
-
2018
- 2018-12-13 US US16/960,733 patent/US20200347479A1/en not_active Abandoned
- 2018-12-13 WO PCT/JP2018/045856 patent/WO2019142559A1/ja unknown
- 2018-12-13 MX MX2020007610A patent/MX2020007610A/es unknown
- 2018-12-13 CN CN201880086633.5A patent/CN111601906B/zh active Active
- 2018-12-13 KR KR1020207019747A patent/KR102561381B1/ko active IP Right Grant
- 2018-12-13 JP JP2019565766A patent/JP6838665B2/ja active Active
- 2018-12-13 EP EP18901386.5A patent/EP3741878B1/en active Active
-
2023
- 2023-05-19 US US18/199,451 patent/US20230287534A1/en active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS609895A (ja) * | 1983-06-27 | 1985-01-18 | Sumitomo Metal Ind Ltd | 合金化電気亜鉛メツキ鋼板の製造方法 |
JPH0633213A (ja) * | 1992-07-17 | 1994-02-08 | Kobe Steel Ltd | 水素脆化の発生しない超高強度亜鉛めっき鋼板 |
JP2001262271A (ja) | 2000-03-17 | 2001-09-26 | Sumitomo Metal Ind Ltd | 電気めっき密着性および延性に優れた高張力鋼板およびその製造方法 |
JP2009035793A (ja) * | 2007-08-03 | 2009-02-19 | Sumitomo Metal Ind Ltd | 熱間プレス鋼板部材の製造方法 |
WO2014132637A1 (ja) * | 2013-02-28 | 2014-09-04 | Jfeスチール株式会社 | 高強度冷延鋼板の製造方法 |
WO2014199923A1 (ja) * | 2013-06-11 | 2014-12-18 | 新日鐵住金株式会社 | ホットスタンプ成形体およびホットスタンプ成形体の製造方法 |
JP2015089946A (ja) * | 2013-11-05 | 2015-05-11 | Jfeスチール株式会社 | 化成処理性および塗装後耐食性に優れた高強度冷延鋼板の製造方法 |
JP2016130358A (ja) | 2015-01-09 | 2016-07-21 | 株式会社神戸製鋼所 | 高強度めっき鋼板、並びにその製造方法 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP7578118B2 (ja) | 2021-05-24 | 2024-11-06 | Jfeスチール株式会社 | Fe系電気めっき高強度鋼板及びその製造方法 |
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