CN104245999A - High-strength hot-dip galvanized steel sheet and process for producing same - Google Patents

High-strength hot-dip galvanized steel sheet and process for producing same Download PDF

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Publication number
CN104245999A
CN104245999A CN201380020566.4A CN201380020566A CN104245999A CN 104245999 A CN104245999 A CN 104245999A CN 201380020566 A CN201380020566 A CN 201380020566A CN 104245999 A CN104245999 A CN 104245999A
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China
Prior art keywords
less
coating
steel plate
steel sheet
hot
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Granted
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CN201380020566.4A
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Chinese (zh)
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CN104245999B (en
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铃木善继
原子大辅
长泷康伸
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JFE Steel Corp
JFE Engineering Corp
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NKK Corp
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
    • C23C2/06—Zinc or cadmium or alloys based thereon
    • 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
    • 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
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76—Adjusting the composition of the atmosphere
    • 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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0447—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the heat treatment
    • C21D8/0463—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the heat treatment following hot rolling
    • 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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0447—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing characterised by the heat treatment
    • C21D8/0473—Final recrystallisation annealing
    • 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
    • C21D8/04—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing
    • C21D8/0478—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips to produce plates or strips for deep-drawing involving a particular surface treatment
    • 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
    • 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
    • C21D9/48—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for sheet metals deep-drawing sheets
    • 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
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/14—Ferrous alloys, e.g. steel alloys containing titanium or zirconium
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0222—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating in a reactive atmosphere, e.g. oxidising or reducing atmosphere
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/02—Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • C23C2/022—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by heating
    • C23C2/0224—Two or more thermal pretreatments
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C23C2/261—After-treatment in a gas atmosphere, e.g. inert or reducing atmosphere
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26—After-treatment
    • C23C2/28—Thermal after-treatment, e.g. treatment in oil bath
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    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
    • C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
    • C23C8/20—Carburising
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    • C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
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    • C21—METALLURGY OF IRON
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    • C21D2211/00—Microstructure comprising significant phases
    • C21D2211/005—Ferrite

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  • Heat Treatment Of Sheet Steel (AREA)
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Abstract

A hot-dip galvannealed steel sheet which comprises a steel sheet that has a composition containing, in terms of mass%, 0.02-0.30% C, 0.01-2.5% Si, 0.1-3.0% Mn, 0.003-0.08% P, up to 0.01% S, 0.001-0.20% Al, and 0.03-0.40% Ti, with the remainder comprising Fe and unavoidable impurities, and a zinc coating layer formed on each of the surfaces thereof in an amount of 20-120 g/m2 per surface, wherein each coating layer contains carbide grains having an average grain diameter of 10 nm or smaller in a number of 5-50 per section and oxide grains having an average grain diameter of 50 nm or larger in a number of 5-50 per section. The section means an area (t11 ([mu]m2)) defined by the coating-layer thickness (t1 [mu]m) and segments obtained by dividing a cross-section of the coating layer in the direction perpendicular to the thickness direction at an interval of 1 [mu]m.

Description

High-strength hot-dip zinc-coated steel sheet and manufacture method thereof
Technical field
The present invention relates to the alloyed hot-dip galvanized steel sheet and manufacture method thereof that are suitable as the antirust surface treated steel plate of automobile.
Background technology
In the component such as vehicle frame, running gear of automobile, truck, use the hot-rolled steel sheet of below TS440MPa level in the past.But recently; in order to improve the impact resistant characteristic of automobile and environment of preserving our planet; advancing the high strength of automotive sheet, thin-walled property, and begin one's study use TS590MPa level, TS780MPa level, be high tensile hot rolled steel sheet more than TS980MPa level further.
Member for automobile is the complex-shaped component obtained by impact briquetting mostly, needs intensity high and the material of excellent processability.On the other hand, from the view point of the antirust power guaranteeing vehicle body while the thin-walled property of steel plate, expect the surface treated steel plate former material steel plate being imparted to rust-preventing characteristic, wherein, special expect erosion resistance after application, excellent weldability and the alloyed hot-dip galvanized steel sheet that can manufacture at an easy rate.
Proposed the high tensile hot rolled steel sheet of several excellent processability or pot galvanize series high strength steel plate and manufacture method thereof in the past.Such as, Patent Document 1 discloses high tensile steel plate and manufacture method thereof that a kind of tensile strength is the excellent processability of more than 590MPa, it is characterized in that, to containing C:0.02 ~ 0.06% in mass %, Si≤0.3%, Mn:0.5 ~ 2.0%, P≤0.06%, S≤0.005%, Al≤0.06%, N≤0.006%, Mo:0.05 ~ 0.5%, Ti:0.03 ~ 0.14% and steel that surplus is made up of Fe in fact carries out melting, it is more than 880 DEG C at finish rolling end temp, coiling temperature is carry out hot rolling under the condition of more than 570 DEG C, it is made to be essentially ferrite single phase structure thus, and the carbide containing Ti and Mo having median size to be less than 10nm is separated out in dispersion.
In addition, Patent Document 2 discloses a kind of manufacture method of pot galvanize series high strength hot-rolled steel sheet, it is characterized in that, to containing C:0.01 ~ 0.1% in mass %, Si≤0.3%, Mn:0.2 ~ 2.0%, P≤0.04%, S≤0.02%, Al≤0.1%, N≤0.006%, Ti:0.03 ~ 0.2% and containing more than one in Mo≤0.5% and W≤1.0%, the steel that surplus is made up of Fe and inevitable impurity carries out melting, hot rolling is carried out in austenite one phase district, batch more than 550 DEG C, manufacture the hot-rolled steel sheet that ferrite is single-phase, then, further except descaling, implement pot galvanize in this condition, thus, make to meet 4.8C+4.2Si+0.4Mn+2Ti≤2.5 in mass %, be organized as the ferrite counting more than 98% with area ratio, and dispersion has in the scope meeting (Mo+W)/(Ti+Mo+W) >=0.2 with atomic ratio measuring containing Ti, and more than one the precipitate being less than 10nm in Mo and W.
But, in patent documentation 1,2, in order to make the fine carbide containing Ti and Mo etc. separate out in ferrite, batch under needing the coiling temperature after finish rolling terminates more than 550 DEG C (below sometimes also referred to as CT).When process being batched to the hot rolling mother metal of the element be more easily oxidized containing Si, Mn geometric ratio Fe (below sometimes also referred to as easily oxidizable element) under so high CT condition, the subscale containing easily oxidizable element is generated in steel plate mother metal skin section, thus, in pot galvanize process afterwards, Alloying Treatment, can exceedingly promote zn-fe alloyization reaction, thus there is the problem of coating adaptation deterioration.In addition, when mother metal steel plate skin section exists a large amount of subscale, there are the following problems: add man-hour at stretch flange formability, and subscale becomes starting point, fine crack is produced, erosion resistance deterioration after the application of stretch flange formability processing department in steel plate skin section and coating.
On the other hand, when in order to suppress the subscale that generates during hot rolling and reduce CT to carry out batch process, can be insufficient and cause intensity, processibility to reduce due to tissue growths such as perlite due to the precipitation of carbide, moreover, meeting occlusion hydrogen when steel plate being annealed in continous way hot-galvanizing equipment afterwards, thus cause the problem of hydrogen embrittlement resistance deterioration.
Prior art document
Patent documentation
Patent documentation 1: Japanese Unexamined Patent Publication 2002-322543 publication
Patent documentation 2: Japanese Unexamined Patent Publication 2003-321736 publication
Summary of the invention
Invent problem to be solved
The present invention completes in view of the foregoing, to its object is to be provided in while guaranteeing good processibility excellent corrosion resistance after the coating adaptation in bending machining portion and the application of stretch flange formability processing department and the excellent high-strength hot-dip zinc-coated steel sheet of hydrogen embrittlement resistance.
For the method for dealing with problems
The plating of the present inventor to high tensile steel plate conducts in-depth research repeatedly, and result obtains following opinion.
First, the present inventor finds, in order to obtain the excellent coated steel sheet of hydrogen embrittlement resistance, the median size of the composition in coating, particularly oxide compound and carbide is extremely important.Think that its reason is, when there is carbide that median size is below 10nm in steel plate skin section and median size is the oxide compound of more than 50nm, the site of catching invaded as hydrogen plays a role, and by suppressing the diffustivity hydrogen concentration in steel plate, inhibits the susceptibility of delayed fracture.In addition, during compressive strain when being subject to impact briquetting, cracking in coating and propagating.In the present invention, by there is fine carbide, oxide compound, in crackle generating unit, fine carbide, oxide compound have pinning effect.Infer and utilize this pinning effect and the propagation of crackle is stopped, can not producing large stripping, coating adaptation during bending machining improves.Its result, after application, erosion resistance improves.
Secondly, about its manufacture method, the present inventor finds, in order to suppress the subscale that generates during hot rolling and control CT, and the solid solution Ti specifying Heating temperature when annealing to steel plate afterwards and make to be present in steel plate skin section to separate out with the form of carbide be important.In addition, the present inventor finds, in order to make Ti oxide compound stably separate out when annealing, need the oxide skin obtained by making steel plate superficial oxidation in heating zone as during reduced anneal in soaking zone, the supply source of the oxygen of Ti internal oxidation effectively to be utilized.In addition, the present inventor finds, in order to during reduced anneal in soaking zone, Ti carbide is stably separated out, and controls the steam partial pressure in furnace atmosphere and hydrogen partial pressure extremely important.Its result, these carbide, oxide compound are inhaled in coating when pot galvanize process and Alloying Treatment and are present in coating, thus after making application, erosion resistance, coating adaptation, hydrogen embrittlement resistance improve.
The present invention completes based on above-mentioned opinion, and its feature is as described below.
[1] alloyed hot-dip galvanized steel sheet, is characterized in that, the coating adhesion amount that surface of steel plate has every one side is 20 ~ 120g/m 2zinc coating, in this coating, median size be below 10nm carbide be more than 5 in each subregion and the ratio of less than 50 exist, median size be more than 50nm oxide compound be more than 5 in each subregion and the ratio of less than 50 existence,
Described steel plate has following one-tenth and is grouped into: in mass %, containing more than C:0.02% and less than 0.30%, more than Si:0.01% and less than 2.5%, more than Mn:0.1% and less than 3.0%, more than P:0.003% and less than 0.08%, below S:0.01%, more than Al:0.001% and less than 0.20%, more than Ti:0.03% and less than 0.40%, and surplus is made up of Fe and inevitable impurity
Wherein, above-mentioned each subregion refers to by thickness of coating (t 1μm) and by coating cross section and the orthogonal direction of thickness direction on carry out splitting with 1 μm of interval and the area (t obtained 1× 1 (μm 2)).
[2] high-strength hot-dip zinc-coated steel sheet as described in [1], is characterized in that, above-mentioned carbide comprises Ti, and above-mentioned oxide compound comprises and is selected from TiO 2, MnO, MnO 2, SiO 2, Al 2o 3, Mn 2siO 4, MnSiO 3in more than one oxide compounds.
[3] high-strength hot-dip zinc-coated steel sheet as described in [1] or [2], it is characterized in that, one-tenth as above-mentioned steel plate is grouped into, in mass % also containing more than Nb:0.001% and less than 0.2%, more than V:0.001% and less than 0.5%, more than Mo:0.01% and less than 0.5%, more than W:0.001% and less than 0.2% in one or more.
[4] high-strength hot-dip zinc-coated steel sheet according to any one of [1] ~ [3], it is characterized in that, the one-tenth as above-mentioned steel plate is grouped into, in mass % also containing more than B:0.0005% and less than 0.005%.
[5] high-strength hot-dip zinc-coated steel sheet according to any one of [1] ~ [4], is characterized in that, above-mentioned steel plate is hot-rolled steel sheet.
[6] a kind of manufacture method of high-strength hot-dip zinc-coated steel sheet, it is characterized in that, hot rolling is implemented to the steel that the one-tenth had according to any one of [1], [3], [4] is grouped into, carries out cooling, batching process after finish rolling terminates, when then carrying out continuous annealing and pot galvanize process
Finish rolling end temp is set as more than 850 DEG C, coiling temperature is set as less than 540 DEG C, carry out continuous annealing under the following conditions,
A () carries out following oxide treatment: be grouped into by the one-tenth of the combustion gases of the heating zone of annealing furnace and be set as H 2>=40 more than volume %, CH 4>=20 volume %, CO 2>=1 volume % and surplus is CO, N 2, C xh y(x>=2, y>=4), the furnace temperature in heating zone is more than 500 DEG C and steel plate is heated to more than 520 DEG C and less than 650 DEG C under the condition of less than 1000 DEG C, and forming thickness on steel plate top layer is the oxide skin of 6 ~ 60nm,
B () then, makes soaking zone atmosphere contain 5 more than volume % and the hydrogen of 50 below volume % and surplus is N 2, and steam partial pressure and hydrogen partial pressure meet following formula (1), make the arrival temperature of steel plate in above-mentioned soaking zone be more than 630 DEG C and less than 780 DEG C carry out reduced anneal,
Wherein, represent steam partial pressure (Pa), represent hydrogen partial pressure (Pa).
The manufacture method of the high-strength hot-dip zinc-coated steel sheet [7] as described in [6], it is characterized in that, after above-mentioned pot galvanize process, further steel plate is heated to more than 450 DEG C and the temperature of less than 510 DEG C and implement Alloying Treatment, be cooled to 400 DEG C with less than 20 DEG C/sec, make the Fe containing ratio in coating be the scope of 7 ~ 15%.
It should be noted that, in the present invention, high strength refers to that tensile strength TS is more than 590MPa.In addition, alloyed hot-dip galvanized steel sheet of the present invention comprise in cold-rolled steel sheet, hot-rolled steel sheet any one, from the viewpoint such as stretch flangeability, hole expandability, particularly preferably hot-rolled steel sheet.
Invention effect
According to the present invention, excellent corrosion resistance after the coating adaptation in bending machining portion while guaranteeing good processibility and the application of stretch flange formability processing department can be obtained and the excellent high-strength hot-dip zinc-coated steel sheet of hydrogen embrittlement resistance.
Embodiment
Below, the present invention is described particularly.In addition, in the following description, the unit of the content of each element of composition of steel composition is " quality % ", below, then only represents with " % " unless otherwise specified.
Below, the present invention is described in detail.
(1) one-tenth of steel plate is grouped into
More than C:0.02% and less than 0.30%
C is for making carbide separate out required element in steel plate, need more than 0.02% for this reason.On the other hand, if more than 0.30%, then weldability deterioration, therefore the upper limit is set as 0.30%.
More than Si:0.01% and less than 2.5%
Si is effective as solution strengthening element, in order to show strengthening effect, needs containing more than 0.01%.On the other hand, if a large amount of containing and more than 2.5%, then in annealing process, the oxide concentration of Si, at surface of steel plate, becomes the reason of generation not being plated defect, the deterioration of coating adaptation, therefore the upper limit is set as 2.5%.
More than Mn:0.1% and less than 3.0%
Mn adds to improve intensity, in order to show strengthening effect, needs containing more than 0.1%.On the other hand, if content is more than 3.0%, then in annealing process, the oxide concentration of Mn is at surface of steel plate, and become the reason of generation not being plated defect, the deterioration of coating adaptation, therefore the upper limit is set as 3.0%.
More than P:0.003% and less than 0.08%
P is one of element inevitably contained, and in order to make it lower than 0.003%, cost may be made to increase, be therefore set as more than 0.003%.On the other hand, during containing P more than 0.08%, weldability deterioration.In addition, surface quality deterioration.In addition, if do not improve alloying treatment temperature when Alloying Treatment, then can not obtain desired alloying degree.If improve alloying treatment temperature to obtain desired alloying degree, then while degrade ductility, alloying plates the deterioration of Coated adaptation.When the addition of P is too high, alloying temperature excessively raises.For the above-mentioned reasons, plate Coated adaptation to take into account desired alloying degree, good ductility and alloying, P is set as less than 0.08%.
Below S:0.01%
S is in crystal boundary generation segregation.Or, when a large amount of generation MnS, toughness can be made to reduce.For the above-mentioned reasons, need to be set as less than 0.01%.The lower limit of the content of S is not particularly limited, and can be impurity levels.
More than Al:0.001% and less than 0.20%
Al adds to carry out deoxidation to molten steel.But, its content lower than 0.001% time, this object can not be reached.On the other hand, if content is more than 0.20%, then inclusion produces in a large number, becomes the reason of steel plate defect.For the above-mentioned reasons, Al is set as more than 0.001% and less than 0.20%.
More than Ti:0.03% and less than 0.40%
Ti is for making carbide separate out and required element of gaining in strength in steel plate, is also effective element from the viewpoint of cost.But, addition lower than 0.03% time, insufficient for increasing the precipitate amount needed for intensity, if more than 0.40%, then its effect is saturated, causes cost increase.For the above-mentioned reasons, Ti is set as more than 0.03% and less than 0.40%.
In addition, in order to control intensity and processibility, following element can also be added except above-mentioned element.
Be selected from more than Nb:0.001% and less than 0.2%, more than V:0.001% and less than 0.5%, more than Mo:0.01% and less than 0.5%, more than W:0.001% and less than 0.2% in one or more
Nb, V, Mo, W separate out with the form comprising the double carbide of Ti in steel plate, being that fine carbide is stable separates out effective element for making, adding one or more in these elements.But when addition is lower than the scope specified, by separating out, the intensity increase effect produced is insufficient, if exceed the scope of regulation, then its effect is saturated, causes cost increase.Therefore, when containing, Nb is set as more than 0.001% and less than 0.2%, V is set as more than 0.001% and less than 0.5%, Mo is set as more than 0.01% and less than 0.5%, W is set as more than 0.001% and less than 0.2%.
More than B:0.0005% and less than 0.005%
B is for the effective element of raising hardening capacity.But, lower than 0.0005% time, be difficult to the effect being promoted quenching.On the other hand, if addition is more than 0.005%, then its effect is saturated, causes cost increase.Therefore, when containing, B is set as more than 0.0005% and less than 0.005%.
Surplus is Fe and inevitable impurity.
(2) carbide existed in coating and oxide compound
The feature of high-strength hot-dip zinc-coated steel sheet of the present invention is, the median size of the carbide existed in coating is below 10nm and the median size of oxide compound is more than 50nm.The median size of carbide is more than 10nm, and crack propagation inhibition is little and make to add the coating adaptation deterioration in man-hour, and hydrogen capture effect is little and make hydrogen embrittlement resistance deterioration.When the median size of oxide compound is less than 50nm, hydrogen capture effect is little and make hydrogen embrittlement resistance deterioration.Meanwhile, make the application of processing department owing to cracking after, erosion resistance is deteriorated.Carbide is to be more than 5 in each subregion and the ratio of less than 50 existence.When being less than 5 in each subregion, hydrogen capture effect is little and make hydrogen embrittlement resistance deterioration.Time in each subregion more than 50, plate the deterioration of Coated processibility and coating adaptation is reduced.
Oxide compound is to be more than 5 in each subregion and the ratio of less than 50 existence.When being less than 5 in each subregion, hydrogen capture effect is little and make hydrogen embrittlement resistance deterioration.Time in each subregion more than 50, plate the deterioration of Coated processibility and coating adaptation is reduced.
It should be noted that, above-mentioned each subregion refers to certain area in coating cross section, and it is by thickness of coating (t 1μm) and by coating cross section and the orthogonal direction of thickness direction on carry out splitting with 1 μm of interval and the area (t obtained 1× 1 (μm 2)).
In the present invention, carbide is preferably containing Ti.In addition, oxide compound contains Ti and is effective containing Si, Mn, Al, specifically, is preferably selected from TiO 2, MnO, MnO 2, SiO 2, Al 2o 3, Mn 2siO 4, MnSiO 3in more than one oxide compounds.This is because, separate out as far as possible in the form of the oxide by making the strengthening element added in steel and make the steel plate skin section softening of the adjacent below in coating, promoting the stress relaxation adding man-hour.
In addition, the carbide in coating, the composition of oxide compound can confirm by the following method.Such as following method can be enumerated: utilize focused ion beam processing unit (plant) (FIB), after thin slice being processed in steel plate cross section in the mode comprising coating, utilize transmission electron microscope (TEM) to observe, and utilize energy dispersion type X-ray detector (EDX) to carry out compositional analysis, electron-beam analysis.In addition, as the measuring method of the median size of the carbide in coating, oxide compound, use by the photo mensuration maximum diameter in above-mentioned observational technique and minimum diameter and the method be averaged.
In addition, high-strength hot-dip zinc-coated steel sheet of the present invention has the coating adhesion amount of every one side is on a surface of a steel sheet 20 ~ 120g/m 2zinc coating.If lower than 20g/m 2, be then difficult to guarantee erosion resistance after application, if more than 120g/m 2, then coating adaptation reduces.
In addition, consider from the reason of stretch flangeability, hole expandability, high-strength hot-dip zinc-coated steel sheet of the present invention is preferably hot-rolled steel sheet.
(3) manufacture method of high-strength hot-dip zinc-coated steel sheet
Then, to the manufacture method of high-strength hot-dip zinc-coated steel sheet of the present invention and limit reason and be described.
First, hot-rolled condition is described.
Finish rolling end temp more than 850 DEG C
When finish rolling end temp is lower than 850 DEG C, the semi-invariant of the strain caused owing to being rolled under the state of non-recrystallization increases, and causes the increase of rolling loads.Therefore, finish rolling end temp is set as more than 850 DEG C.The upper limit is not particularly limited.In the present invention, be preferably less than 1100 DEG C.
Coiling temperature less than 540 DEG C
When coiling temperature is more than 540 DEG C, subscale can be formed due to easily oxidizable element, when pot galvanize process afterwards, Alloying Treatment, exceedingly promote zn-fe alloyization reaction, cause thus because produce alloying uneven and cause the deterioration of aesthetic appearance, the deterioration of erosion resistance after the reduction of the coating adaptation in bending machining portion and the application in stretch flange formability portion.In addition, because internal oxidation is carried out, the Ti that the Formed Chemistry and Physics Institute needs is consumed, and therefore, the carbide forming elements such as Ti are consumed because of internal oxidation, thus forms scarce Ti layer.Therefore, be difficult to make in coating, to there is enough Ti carbide.Therefore, coiling temperature is set as less than 540 DEG C.
Then, continuous annealing and pot galvanize process are described.
The composition of the gas of the heating zone of annealing furnace consists of H 2>=40 more than volume %, CH 4>=20 volume %, CO 2>=1 volume %, surplus CO, N 2, C xh y(x>=2, y>=4)
H 2, CH 4, CO 2time few, the surface-activation effect after redox is little, and the carbide, the oxide compound that are formed in the adjacent below in coating during reduced anneal are difficult to be inhaled in coating.Therefore, be difficult to obtain the most important effect supplying carbide and oxide compound in coating in the present invention.The upper limit is not particularly limited.About balance gas, even denier, as long as but be mixed into these gas, then also can obtain same effect.Combustion gases can be mixed into hydrogen and be formed in Sweet natural gas, industrial methane, ethane, propane gas etc., also can use the coke-oven gas generated by so-called water-gas reaction.But the burn calories of coke-oven gas is according to the mine of the coal produced as raw material, the operation factor of coke oven and changing.Therefore, sometimes need to carry out modifying ingredients by adding hydrogen etc., therefore, coke-oven gas might not directly use.
The furnace temperature more than 500 DEG C of heating zone and less than 1000 DEG C
When furnace temperature is lower than 500 DEG C, surface of steel plate produces oxidation inequality and can not be substantially oxidized, and therefore, the effect that carbide, oxide compound suck in coating can not be carried out equably.During more than 1000 DEG C, surface of steel plate over oxidation, the interface of coating and steel plate becomes coarse, adds the coating adaptation deterioration in man-hour.
The Heating temperature of the steel plate in heating zone is more than 520 DEG C and less than 650 DEG C
During lower than 520 DEG C, surface of steel plate can not be fully oxidized, and therefore, effect carbide, oxide compound sucked in coating is little.During more than 650 DEG C, meeting over oxidation, the interface of coating and steel plate becomes coarse, adds the coating adaptation deterioration in man-hour.
Steel plate top layer is formed the oxide treatment that thickness is the oxide skin of 6 ~ 60nm
In the present invention, when being less than 6nm, the amount of oxidation of surface of steel plate is insufficient, and therefore, effect carbide and oxide compound sucked in coating is little.When being greater than 60nm, meeting over oxidation, the interface of coating and steel plate becomes coarse, adds the coating adaptation deterioration in man-hour.In addition, the oxide skin in the present invention refers to based on Fe oxide skin, the oxide skin (referring to that Ti is the oxide skin of less than 0.001%) not containing in fact Ti.When the Heating temperature of steel plate is more than 650 DEG C, Ti is inhaled in ferric oxide in the form of the oxide.The oxide compound of this Ti remains in interface when reduced anneal and makes the interface of coating and steel plate become coarse, therefore, adds the coating adaptation deterioration in man-hour, thus not preferred.
Soaking zone atmosphere contains 5 more than volume % and the hydrogen of 50 below volume % and surplus is N 2, and steam partial pressure and hydrogen partial pressure meet formula (1).
H 2when being less than 5 volume %, surface of steel plate can not be reduced sufficiently, and therefore, remains oxide compound and erosion resistance deterioration after making application in interface.During more than 50 volume %, a large amount of hydrogen of steel plate occlusion, therefore, makes plating tunicle produce bubble etc. and make surface quality deterioration.Surplus is set as N 2.Further, steam partial pressure with hydrogen partial pressure than demand fulfillment following formula (1).
be less than 10 -3(0.0010), time, there is nitrogenize and can not form carbide in Ti.On the other hand, be greater than 10 -1(0.1000), time, there is internal oxidation when annealing and be consumed in Ti, thus cannot form carbide.
During reduced anneal, the arrival temperature of steel plate in soaking zone is more than 630 DEG C and less than 780 DEG C
During lower than 630 DEG C, surface can not activate, and can not obtain effect carbide and oxide compound introduced in coating, therefore not preferred.During more than 780 DEG C, optionally there is external oxidation and be consumed in Ti, thus cannot form carbide.H 2the control of O composition is implemented by the following method: outside annealing furnace, arrange bubbling device, by the N of predetermined amount of flow 2gas passes into the tank being held in room temperature, with the N of not humidification in advance 2gas and vapor permeation also imports in stove.In addition, now, need gas is flowed into from the bottom of annealing furnace.This is because, H 2the light specific gravity of O, therefore H 2o stays in stove internal upper part.At this, lower portion of furnace body represents relative to the whole height of body of heater until the height of 1/10.
H is measured by dew point 2o and H 2the method of dividing potential drop is not particularly limited.Such as, the gas of sampling predetermined amount, utilizes the dew point measurement device such as Dew Cup to measure dew point to it, obtains H 2o dividing potential drop.Similarly, commercially available H is utilized 2partial pressure gauges measures H 2dividing potential drop.Or, if measure the pressure in atmosphere, then can calculate H by concentration ratio 2o, H 2dividing potential drop.
In addition, hot-dip galvanizing sheet steel of the present invention can be implemented Alloying Treatment and make alloyed hot-dip galvanized steel sheet after pot galvanize process.In this case, steel plate is heated to more than 450 DEG C and the temperature of less than 510 DEG C and implement Alloying Treatment, is cooled to 400 DEG C with less than 20 DEG C/sec.Fe containing ratio in the coating obtained like this is 7 ~ 15%.Fe containing ratio lower than 7% time, not only can cannot obtain uniform appearance because producing alloying inequality, and can be insufficient and thicklyer on coating top layer generate soft ζ phase due to zn-fe alloyization reaction, cause producing when bending machining that coating peels off with flakey peels off.On the other hand, during more than 15%, zn-fe alloy overreact is carried out, coating and the near interface of steel plate thicker generate crisp Γ phase, thus make coating adaptation deterioration.
When alloying temperature is lower than 450 DEG C, alloying reaction can not fully carry out.During more than 510 DEG C, Γ phase can be formed thicklyer and make the coating adaptation of processing department deteriorated.After alloying, be cooled to 400 DEG C with less than 20 DEG C/sec.When speed of cooling is slow, Γ phase can be generated thicklyer, thus make the deterioration of coating adaptation.
Embodiment 1
By having after the steel billet becoming to be grouped into shown in table 1 heats at 1250 DEG C, carrying out hot rolling under the conditions shown in Table 2, removing black oxidation skin further by pickling, making the hot-rolled steel sheet that thickness is 2.3mm.
Then, CGL production line is utilized to carry out continuous annealing process, pot galvanize process.In CGL, in heating zone, make composition be adjusted to the coke-oven gas burning of predetermined composition and implement oxide treatment, then, in soaking zone, be up to Da Wendu with condition control furnace atmosphere, steam partial pressure, hydrogen partial pressure and the steel plate shown in table 2 and reduction treatment is implemented to steel plate.In addition, about the control of the dew point in atmosphere, arranging flowing in advance in addition has by being arranged on N 2tank in gas line carries out heating and by the N after humidification 2the pipe arrangement of gas, by H 2gas imports to the N after humidification 2mix in gas, and imported in stove, thus the dew point of controlled atmosphere gas.In addition, the H in atmosphere 2the control of concentration imports to N by utilizing air valve to regulate 2h in gas 2the amount of gas is carried out.
Then, being immersed in bath temperature is in the bath of the Zn containing Al of 460 DEG C, implements pot galvanize process.Coating adhesion amount is now adjusted to every one side by airblast be 45g/m 2(thickness of coating t 1: 6 μm), 70g/m 2(thickness of coating t 1: 10 μm), 140g/m 2(thickness of coating t 1: 20 μm).For alloyed hot-dip galvanized steel sheet, after pot galvanize process, implement Alloying Treatment.
For the hot-dip galvanizing sheet steel obtained by aforesaid method (GI) and alloyed hot-dip galvanized steel sheet (GA), investigate erosion resistance after the application of aesthetic appearance (coating surface outward appearance), processibility, the coating adaptation in bending machining portion, hydrogen embrittlement resistance, stretch flange formability processing department.Measuring method and metewand as follows.In addition, the carbide in coating and the size of oxide compound carry out observation analysis to measure to the plating film sample after FIB processing by utilizing TEM-EDX, EELS with composition.In addition, for the steel plate top layer after heating, X-ray diffraction method is utilized to identify oxide compound kind and analyze.
< aesthetic appearance >
For aesthetic appearance, by not there is plating, the situation of the unequal coating surface bad order of alloying is judged to be outward appearance good (zero), and by not there is plating, the situation of the unequal coating surface bad order of alloying is judged to be bad order (×).
< processibility >
JIS5 tension test sheet is cut along the direction being 90 ° relative to rolling direction from sample, the pinblock constant airspeed that is defined according to JIS Z 2241 is carry out tension test under the condition of 10mm/ minute, measure tensile strength (TS (MPa)) and elongation (El (%)), using the situation of TS × El >=15000 as well, using the situation of TS × El < 15000 as bad.
In addition, utilize the drift of 10mm φ with 12.5% gap carry out stamping-out to prepare having the test film in hole in the central authorities being cut into the square steel plate of 130mm, 60 ° of circular cone drifts are utilized upwards to push up from the reverse direction of the burr side in stamping-out hole, measure the aperture d (mm) during penetration of cracks steel plate, calculate hole expansibility λ according to the following formula.
λ(％)＝[(d-10)/10]×100
The coating adaptation > in < bending machining portion
For do not implement Alloying Treatment hot-dip galvanizing sheet steel coating adaptation for, by after steel plate bending to 180 °, carry out tape stripping to the outside in bending machining portion, visual judgement coating is with or without stripping and evaluate as follows.
Zero: coating is unstripped
×: coating is peeled off
In addition, the coating adaptation of alloyed hot-dip galvanized steel sheet is evaluated by efflorescence shown below test.
Coated steel sheet pastes adhesive tape, makes adhesive tape sticking face as inner side, carry out 90 ° of bending recoveries with the bending radius of 5mm, utilize fluorescent X-ray to analyze the adhesive tape stripped down.Obtain the Zn counting of per unit length now, as coating overburden amount.About resistance to chalking, with reference to following benchmark, the average evaluation being grade 1 by the coating overburden amount obtained in aforesaid efflorescence test is good (◎), the average evaluation being grade 2 by the coating overburden amount obtained in aforesaid efflorescence test is roughly good (zero), and the average evaluation being grade 3 by the coating overburden amount obtained in aforesaid efflorescence test is bad (×).◎, zero is qualified.
Coating overburden amount: grade
More than 0 and be less than 3000:1 (good (◎))
More than 3000 and be less than 6000:2 (good (zero))
More than 6000: 3 (bad (×))
< hydrogen embrittlement resistance >
Carry out bending machining with the long strip shape test film of the bending radius of 5mm to 150mm × 30mm, the strain gage of water tolerance is installed from the teeth outwards, is immersed in the sulfuric acid of 0.5mol/L, with 0.1mA/cm 2current density this test film is energized, carry out electrolysis thus, make hydrogen enter test film, evaluate according to the generation of following benchmark to the crackle of energising after 2 hours.
Well (zero): do not crack
Bad (×): crack
Erosion resistance > after < application
Utilize the drift of 10mm φ with 12.5% gap carry out stamping-out to prepare having the test film in hole in the central authorities being cut into the square steel plate of 130mm, utilize 60 ° of circular cone drifts upwards to push up from the reverse direction of the burr side in stamping-out hole, implement reaming processing.Now, upwards push up until hole expansibility reaches the value of crack 80%.For the test film after such processing, implement chemical conversion treatment, electrodeposition coating, carry out 10 days salt spray testings based on JIS Z 2371 (2000), processing department is evaluated with or without expansion.
Well (zero): without expanding
Bad (×): have expansion
The result obtained by aforesaid method and manufacturing condition are shown in the lump and show 2-1, show 2-2, show 3-1, show in 3-2.
Table 2-2
Table 3-2
According to table 2-1, table 2-2, table 3-1, table 3-2, erosion resistance all good (zero) after the application of the coating adaptation in the aesthetic appearance of example of the present invention, processibility, bending machining portion, hydrogen embrittlement resistance and stretch flange formability processing department.On the other hand, any one evaluation not meeting the comparative example of the scope of the invention is lower.

Claims (7)

1. an alloyed hot-dip galvanized steel sheet, is characterized in that, the coating adhesion amount that surface of steel plate has every one side is 20 ~ 120g/m 2zinc coating, in this coating, median size be below 10nm carbide be more than 5 in each subregion and the ratio of less than 50 exist, median size be more than 50nm oxide compound be more than 5 in each subregion and the ratio of less than 50 existence,
Described steel plate has following one-tenth and is grouped into: in mass %, containing more than C:0.02% and less than 0.30%, more than Si:0.01% and less than 2.5%, more than Mn:0.1% and less than 3.0%, more than P:0.003% and less than 0.08%, below S:0.01%, more than Al:0.001% and less than 0.20%, more than Ti:0.03% and less than 0.40%, and surplus is made up of Fe and inevitable impurity
Wherein, described each subregion refers to by thickness of coating (t 1μm) and by coating cross section and the orthogonal direction of thickness direction on carry out splitting with 1 μm of interval and the area (t obtained 1× 1 (μm 2)).
2. high-strength hot-dip zinc-coated steel sheet as claimed in claim 1, it is characterized in that, described carbide comprises Ti, and described oxide compound comprises and is selected from TiO 2, MnO, MnO 2, SiO 2, Al 2o 3, Mn 2siO 4, MnSiO 3in more than one oxide compounds.
3. high-strength hot-dip zinc-coated steel sheet as claimed in claim 1 or 2, it is characterized in that, one-tenth as described steel plate is grouped into, in mass % also containing more than Nb:0.001% and less than 0.2%, more than V:0.001% and less than 0.5%, more than Mo:0.01% and less than 0.5%, more than W:0.001% and less than 0.2% in one or more.
4. the high-strength hot-dip zinc-coated steel sheet according to any one of claims 1 to 3, is characterized in that, the one-tenth as described steel plate is grouped into, in mass % also containing more than B:0.0005% and less than 0.005%.
5. the high-strength hot-dip zinc-coated steel sheet according to any one of Claims 1 to 4, is characterized in that, described steel plate is hot-rolled steel sheet.
6. the manufacture method of a high-strength hot-dip zinc-coated steel sheet, it is characterized in that, hot rolling is implemented to the steel that the one-tenth had according to any one of claim 1,3,4 is grouped into, carries out cooling, batching process after finish rolling terminates, when then carrying out continuous annealing and pot galvanize process
Finish rolling end temp is set as more than 850 DEG C, coiling temperature is set as less than 540 DEG C, carry out described continuous annealing under the following conditions,
A () carries out following oxide treatment: be grouped into by the one-tenth of the gas of the heating zone of annealing furnace and be set as H 2>=40 more than volume %, CH 4>=20 volume %, CO 2>=1 volume % and surplus is CO, N 2, C xh y(x>=2, y>=4), the furnace temperature in heating zone is more than 500 DEG C and steel plate is heated to more than 520 DEG C and less than 650 DEG C under the condition of less than 1000 DEG C, and forming thickness on steel plate top layer is the oxide skin of 6 ~ 60nm,
B () then, makes soaking zone atmosphere contain 5 more than volume % and the hydrogen of 50 below volume % and surplus is N 2, and steam partial pressure and hydrogen partial pressure meet following formula (1), make the arrival temperature of steel plate in described soaking zone be more than 630 DEG C and less than 780 DEG C carry out reduced anneal,
10 - 3 &le; P H 2 O / P H 2 &le; 10 - 1 - - - ( 1 )
Wherein, represent steam partial pressure (Pa), represent hydrogen partial pressure (Pa).
7. the manufacture method of high-strength hot-dip zinc-coated steel sheet as claimed in claim 6, it is characterized in that, after described pot galvanize process, further steel plate is heated to more than 450 DEG C and the temperature of less than 510 DEG C and implement Alloying Treatment, be cooled to 400 DEG C with less than 20 DEG C/sec, make the Fe containing ratio in coating be the scope of 7 ~ 15%.
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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6417843A (en) * 1987-07-13 1989-01-20 Nippon Steel Corp Hot dip alloyed galvanized steel sheet

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0663119B2 (en) * 1987-02-19 1994-08-17 新日本製鐵株式会社 Double-layer plated steel sheet with excellent resistance weldability
EP1041167B1 (en) * 1998-09-29 2011-06-29 JFE Steel Corporation High strength thin steel sheet and high strength alloyed hot-dip zinc-coated steel sheet.
US6537394B1 (en) * 1999-10-22 2003-03-25 Kawasaki Steel Corporation Method for producing hot-dip galvanized steel sheet having high strength and also being excellent in formability and galvanizing property
JP3951552B2 (en) * 2000-05-02 2007-08-01 住友金属工業株式会社 Hot rolled steel sheet with excellent surface properties and method for producing the same
JP3591502B2 (en) 2001-02-20 2004-11-24 Ｊｆｅスチール株式会社 High-tensile steel sheet excellent in workability, and its manufacturing method and processing method
JP3821043B2 (en) 2002-04-30 2006-09-13 Ｊｆｅスチール株式会社 Hot-dip galvanized high-strength hot-rolled steel sheet with excellent weldability, manufacturing method and processing method thereof
US8592049B2 (en) * 2006-01-30 2013-11-26 Nippon Steel & Sumitomo Metal Corporation High strength hot dip galvanized steel sheet and high strength galvannealed steel sheet excellent in shapeability and plateability
JP5162836B2 (en) * 2006-03-01 2013-03-13 新日鐵住金株式会社 High-strength cold-rolled steel sheet excellent in hydrogen embrittlement resistance of welds and method for producing the same
JP5044976B2 (en) * 2006-05-02 2012-10-10 Ｊｆｅスチール株式会社 Method for producing alloyed hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet
KR101138042B1 (en) * 2006-05-02 2012-04-24 제이에프이 스틸 가부시키가이샤 Method of manufacturing hot dip galvannealed steel sheet and hot dip galvannealed steel sheet

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6417843A (en) * 1987-07-13 1989-01-20 Nippon Steel Corp Hot dip alloyed galvanized steel sheet

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