JP2011224584A - Method of manufacturing hot-rolled steel sheet and method of manufacturing hot-dip galvanized steel sheet - Google Patents

Method of manufacturing hot-rolled steel sheet and method of manufacturing hot-dip galvanized steel sheet Download PDF

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JP2011224584A
JP2011224584A JP2010094621A JP2010094621A JP2011224584A JP 2011224584 A JP2011224584 A JP 2011224584A JP 2010094621 A JP2010094621 A JP 2010094621A JP 2010094621 A JP2010094621 A JP 2010094621A JP 2011224584 A JP2011224584 A JP 2011224584A
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hot
steel sheet
rolled steel
slab
rolled
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Yoshitsugu Suzuki
善継 鈴木
Yoshiharu Sugimoto
芳春 杉本
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JFE Steel Corp
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JFE Steel Corp
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Priority to JP2010094621A priority Critical patent/JP2011224584A/en
Priority to TW100112651A priority patent/TWI458832B/en
Priority to CA2794658A priority patent/CA2794658C/en
Priority to KR1020127028948A priority patent/KR20130018846A/en
Priority to EP11768981.0A priority patent/EP2548664A4/en
Priority to KR1020157001527A priority patent/KR20150013954A/en
Priority to PCT/JP2011/059768 priority patent/WO2011129465A1/en
Priority to MX2012011761A priority patent/MX2012011761A/en
Priority to BR112012026457A priority patent/BR112012026457A2/en
Priority to US13/641,267 priority patent/US20130202801A1/en
Priority to CN201180018720.5A priority patent/CN102844126B/en
Publication of JP2011224584A publication Critical patent/JP2011224584A/en
Withdrawn legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B9/00—Measures for carrying out rolling operations under special conditions, e.g. in vacuum or inert atmosphere to prevent oxidation of work; Special measures for removing fumes from rolling mills
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B45/004—Heating the product
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D11/00—Bending not restricted to forms of material mentioned in only one of groups B21D5/00, B21D7/00, B21D9/00; Bending not provided for in groups B21D5/00 - B21D9/00; Twisting
    • B21D11/06—Bending into helical or spiral form; Forming a succession of return bends, e.g. serpentine form
    • 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
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226—Hot rolling
    • 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
    • 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
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
    • C21D9/54—Furnaces for treating strips or wire
    • C21D9/56—Continuous furnaces for strip or wire
    • C21D9/561—Continuous furnaces for strip or wire with a controlled atmosphere or vacuum
    • 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
    • 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
    • C23C2/003—Apparatus
    • C23C2/0038—Apparatus characterised by the pre-treatment chambers located immediately upstream of the bath or occurring locally before the dipping process
    • 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
    • C23C2/024—Pretreatment of the material to be coated, e.g. for coating on selected surface areas by cleaning or etching
    • 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
    • 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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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Thermal Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Coating With Molten Metal (AREA)
  • Metal Rolling (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a hot-rolled steel sheet that controls oxide scale (mill scale) formed on the surface of the steel sheet through hot rolling, prevents the occurrence of surface defects caused by red scale for Si-containing hot-rolled steel sheet to achieve excellent appearance, and is suitable for manufacturing a hot-dip galvanized steel sheet in which the occurrence of appearance defects due to non-coating or red scale is prevented and excellent appearance is achieved; and to provide a method of manufacturing the hot-dip galvanized steel sheet, which prevents appearance defects due to non-plating or red scale and achieves excellent appearance not depending on types of CGL heating furnaces.SOLUTION: The method of manufacturing the hot-rolled steel sheet includes a slab heating step of heating a steel slab in a slab heating furnace, a step of hot-rolling the heated steel slab to obtain a steel strip by a rough rolling mill and a finish rolling mill, and a winding step of winding the steel strip by a winder. The steps from the slab heating step to the winding step are performed in a non-oxidizing atmosphere.

Description

本発明は、鋼スラブを熱間圧延する際に鋼表面に酸化スケールが生成するのを抑制し、良好な外観を有する熱延鋼板を製造する方法に関する。また、本発明は、溶融亜鉛めっきに適したＳｉ含有熱延鋼板の製造方法に関する。また、本発明は、Ｓｉ含有高強度鋼板を母材として溶融亜鉛めっき鋼板を製造する方法に関する。   The present invention relates to a method for producing a hot-rolled steel sheet having a good appearance by suppressing generation of oxide scale on the steel surface when hot rolling a steel slab. The present invention also relates to a method for producing a Si-containing hot rolled steel sheet suitable for hot dip galvanizing. The present invention also relates to a method for producing a hot-dip galvanized steel sheet using a Si-containing high-strength steel sheet as a base material.

一般に、熱延鋼板は、鋼スラブを熱間圧延し、巻取り機に巻き取られて製造される。巻取り機に巻き取られた熱延鋼板の表面には、スラブ加熱工程から巻取り工程までの熱間圧延工程で生成した酸化スケール（黒皮スケール）が存在する。   Generally, a hot-rolled steel sheet is manufactured by hot-rolling a steel slab and winding it on a winder. On the surface of the hot-rolled steel sheet wound by the winder, there is an oxide scale (black scale) generated in the hot rolling process from the slab heating process to the winding process.

熱延鋼板には、熱間圧延工程で生成した酸化スケールが存在する状態で出荷するもの（所謂「黒皮材」）と、酸化スケールを除去した状態で出荷するもの（所謂「白皮材」）がある。白皮材は、熱延鋼板を酸洗して表面の酸化スケールを除去した後出荷する。   Hot-rolled steel sheets are shipped in the presence of oxide scale generated in the hot rolling process (so-called “black skin material”), and are shipped with the oxide scale removed (so-called “white skin material”). ) The white skin material is shipped after pickling the hot-rolled steel sheet to remove the oxidized scale on the surface.

熱間圧延工程で酸化スケールの生成を抑制できれば、酸化スケールを除去するための酸洗工程が不要になるが、これまで、熱間圧延工程で酸化スケールの生成を抑制する技術は提案されていない。   If the production of oxide scale can be suppressed in the hot rolling process, a pickling process for removing the oxide scale becomes unnecessary, but no technology has been proposed so far to suppress the production of oxide scale in the hot rolling process. .

近年、地球環境の保全の見地から、自動車の燃費向上が重要な課題となっており、車体材料の高強度化により薄肉化を図り、車体そのものを軽量化しようとする動きが活発となってきている。鋼中にＳｉを添加すると、加工性に優れた高強度鋼板を製造出来る可能性がある。しかし、鋼中にＳｉを添加した鋼スラブを使用すると、熱間圧延工程で赤スケールと呼ばれる表面欠陥（以下「赤スケール疵」と記載する。）が多発する問題があり、熱延鋼板の外観品質を劣化させる。   In recent years, improving the fuel efficiency of automobiles has become an important issue from the viewpoint of protecting the global environment, and efforts to reduce the thickness of the car body by increasing the strength of the car body material and reducing the weight of the car body have become active. Yes. When Si is added to the steel, there is a possibility that a high-strength steel plate excellent in workability can be produced. However, when a steel slab with Si added to the steel is used, there is a problem that surface defects called red scale (hereinafter referred to as “red scale wrinkles”) frequently occur in the hot rolling process. Deteriorate quality.

また、近年、自動車、家電、建材等の分野において、鋼板に防錆性を付与した表面処理鋼板、中でも防錆性に優れた溶融亜鉛めっき鋼板が使用されている。熱延鋼板は、溶融亜鉛めっき用途にも使用される。溶融亜鉛めっき用途に使用するときは、熱延鋼板を酸洗して表面の酸化スケールを除去した薄鋼板、または酸洗後さらに冷間圧延を施した薄鋼板をめっきの母材鋼板とする。この母材鋼板を、ＣＧＬ（連続溶融亜鉛めっきライン）で、前処理工程にて脱脂して再結晶焼鈍し、その後、溶融亜鉛めっきを施し、またはさらに合金化処理を施すことで、溶融亜鉛めっき鋼板を製造する。   In recent years, surface-treated steel sheets imparted with rust resistance to steel sheets, particularly hot dip galvanized steel sheets with excellent rust resistance have been used in fields such as automobiles, home appliances, and building materials. Hot-rolled steel sheets are also used for hot dip galvanizing applications. When used for hot dip galvanizing, a thin steel plate obtained by pickling a hot-rolled steel plate to remove the oxide scale on the surface, or a thin steel plate subjected to cold rolling after pickling is used as a base metal plate for plating. This base steel sheet is degreased and recrystallized and annealed in a pretreatment process using a CGL (continuous hot dip galvanizing line), and then hot dip galvanized or further alloyed, thereby hot dip galvanized. Manufacture steel sheets.

Ｓｉ含有高強度鋼板を溶融亜鉛めっきすると、赤スケール疵に起因する外観不良だけでなく、鋼板表層にＳｉ酸化物が生成してめっき性を阻害する問題がある。   When hot-dip galvanizing a Si-containing high-strength steel plate, there is a problem that not only poor appearance due to red scale wrinkles, but also Si oxide is generated on the surface layer of the steel plate and hinders plating properties.

ＣＧＬの加熱炉の形式には、ＤＦＦ（直火型）、ＮＯＦ（無酸化型）、オールラジアントチューブ型等があるが、近年、操業し易く、炉内ロールにピックアップが発生しにくいことからオールラジアントチューブ型ＣＧＬの建設が増加している。オールラジアントチューブ型ＣＧＬは、ＤＦＦ（直火型）、ＮＯＦ（無酸化型）と異なり、事前に酸化工程がないため、Ｓｉ、Ｍｎ等の易酸化性元素を含む高強度鋼板は鋼板表層にＳｉ酸化物、Ｍｎ酸化物が生成し、良好なめっき性を確保する上で不利である。   CGL heating furnace types include DFF (direct flame type), NOF (non-oxidation type), all radiant tube type, etc., but all of them are easy to operate in recent years and pick-up is not likely to occur in the furnace roll. Construction of radiant tube type CGL is increasing. Unlike DFF (direct flame type) and NOF (non-oxidation type), all radiant tube type CGL does not have an oxidation process in advance. Therefore, high-strength steel sheets containing oxidizable elements such as Si and Mn are formed on the surface of the steel sheet. Oxides and Mn oxides are generated, which is disadvantageous in securing good plating properties.

めっきの母材鋼板にＳｉ、Ｍｎ等の易酸化性元素を多量に含む高強度鋼板を使用して、オールラジアントチューブ型ＣＧＬで良好なめっき性を確保する技術として、特許文献１には、溶融亜鉛めっきままのめっき層を有する溶融亜鉛めっき鋼板（ＧＩ）を製造する際に還元炉における加熱温度を雰囲気の水蒸気分圧との関係で規定するとともに、露点を上げ、酸素ポテンシャルを上げることで、Ｓｉ、Ｍｎ等を内部酸化させる技術が開示され、特許文献２には、溶融亜鉛めっき後めっき層を合金化処理する溶融亜鉛めっき鋼板（ＧＡ）を製造する際に還元炉における加熱温度を雰囲気の水蒸気分圧との関係で規定するとともに、露点を上げ、酸素ポテンシャルを上げることで、Ｓｉ、Ｍｎ等を内部酸化させる技術が開示されている。しかしながら、これらの技術では、炉体の損傷が激しいため良好な外観を有するＳｉ含有高強度溶融亜鉛めっき鋼板を製造することができない。   As a technique for ensuring good plating properties with an all-radiant tube type CGL using a high-strength steel plate containing a large amount of easily oxidizable elements such as Si and Mn as a base metal plate for plating, Patent Document 1 discloses melting. When manufacturing a hot-dip galvanized steel sheet (GI) having a galvanized coating layer, the heating temperature in the reduction furnace is specified in relation to the water vapor partial pressure of the atmosphere, raising the dew point, and raising the oxygen potential, A technique for internally oxidizing Si, Mn, etc. is disclosed, and in Patent Document 2, the heating temperature in the reduction furnace is set to the atmospheric temperature when manufacturing a hot-dip galvanized steel sheet (GA) for alloying the plated layer after hot-dip galvanizing. A technique is disclosed in which Si, Mn, and the like are internally oxidized by increasing the dew point and increasing the oxygen potential as well as by the relationship with the water vapor partial pressure. However, these techniques cannot produce a Si-containing high-strength hot-dip galvanized steel sheet having a good appearance because the furnace body is severely damaged.

また特許文献３には、還元帯の雰囲気として、酸化性ガスであるＨ２Ｏ、Ｏ２濃度の規定に加えて、さらにＣＯ２濃度を規定することで、酸素ポテンシャルを上げてＳｉ、Ｍｎ等を内部酸化させて外部酸化を抑制し、めっき外観を改善する技術が開示されている。しかしながら、この技術には、ＣＯ２に起因する炉内汚染によるめっき外観の劣化や、鋼板表層への浸炭による機械特性の変化などの懸念がある。 Further, in Patent Document 3, as the atmosphere of the reduction zone, in addition to the definition of the oxidizing gas H 2 O and O 2 concentration, the CO 2 concentration is further defined to increase the oxygen potential, and Si, Mn, etc. A technique for improving the appearance of plating by suppressing external oxidation by internally oxidizing the metal is disclosed. However, this technology has concerns such as deterioration of the plating appearance due to in-furnace contamination caused by CO 2 and changes in mechanical properties due to carburization of the steel sheet surface layer.

そのため、めっきの母材鋼板として、Ｓｉ、Ｍｎ等の易酸化性元素を多量に含む高強度鋼板を使用した場合、オールラジアントチューブ型ＣＧＬでは、良好なめっき性を有する溶融亜鉛めっき鋼板を製造することができなかった。   Therefore, when a high-strength steel plate containing a large amount of easily oxidizable elements such as Si and Mn is used as the base metal plate for plating, the all-radiant tube type CGL produces a hot-dip galvanized steel plate having good plating properties. I couldn't.

特開２００４−３２３９７０号公報JP 2004-323970 A 特開２００４−３１５９６０号公報JP 2004-315960 A 特開２００６−２３３３３３号公報JP 2006-233333 A

本発明はかかる事情に鑑みてなされたものであって、熱間圧延工程で鋼板表面に酸化スケール（黒皮スケール）の生成を抑制できる熱延鋼板の製造方法を提供することを課題とする。また、本発明は、Ｓｉ含有熱延鋼板に対して、さらに、赤スケール疵の発生を防止して、美麗な外観を有する熱延鋼板の製造方法を提供することを課題とする。   This invention is made | formed in view of this situation, Comprising: It makes it a subject to provide the manufacturing method of the hot-rolled steel plate which can suppress the production | generation of an oxide scale (black skin scale) on the steel plate surface at a hot rolling process. Moreover, this invention makes it a subject to provide the manufacturing method of the hot rolled sheet steel which prevents generation | occurrence | production of a red scale wrinkle with respect to Si containing hot rolled sheet steel, and has a beautiful external appearance.

また、本発明は、不めっきや赤スケール疵に起因する外観不良の発生を防止して美麗な外観を有する溶融亜鉛めっき鋼板の製造に適した熱延鋼板の製造方法を提供することを課題とする。また、本発明は、ＣＧＬの加熱炉の形式に係わらず、不めっきや赤スケール疵に起因する外観不良が発生せず、美麗な外観を有する溶融亜鉛めっき鋼板の製造方法を提供することを課題とする。   Another object of the present invention is to provide a method for producing a hot-rolled steel sheet suitable for producing a hot-dip galvanized steel sheet having a beautiful appearance by preventing occurrence of poor appearance due to non-plating and red scale wrinkles. To do. In addition, the present invention provides a method for producing a hot-dip galvanized steel sheet having a beautiful appearance without causing appearance defects due to non-plating or red scale defects regardless of the type of heating furnace of CGL. And

上記課題を解決する本発明の手段は、次のとおりである。   Means of the present invention for solving the above-described problems are as follows.

［１］鋼スラブをスラブ加熱炉にて加熱するスラブ加熱工程、加熱した鋼スラブを粗圧延機及び仕上圧延機で熱間圧延してストリップとする工程、ストリップを巻取り機に巻き取る巻取り工程を行う熱延鋼板の製造方法において、スラブ加熱工程〜巻取り工程までの工程の雰囲気を非酸化性雰囲気にすることを特徴とする熱延鋼板の製造方法。   [1] A slab heating process in which a steel slab is heated in a slab heating furnace, a process in which the heated steel slab is hot-rolled with a roughing mill and a finishing mill to form a strip, and winding the strip into a winder In the manufacturing method of the hot-rolled steel sheet which performs a process, the atmosphere of the process from a slab heating process to a winding process is made into a non-oxidizing atmosphere, The manufacturing method of the hot-rolled steel sheet characterized by the above-mentioned.

［２］前記非酸化性雰囲気はＮ２雰囲気であることを特徴とする［１］に記載の熱延鋼板の製造方法。 [2] The method for manufacturing a hot-rolled steel sheet according to [1], wherein the non-oxidizing atmosphere is an N 2 atmosphere.

［３］ 前記非酸化性雰囲気は、さらにＨ２を１〜１０ｖｏｌ％含み、かつ露点が−４０℃〜＋２０℃であることを特徴とする［２］に記載の熱延鋼板の製造方法。 [3] The method for producing a hot-rolled steel sheet according to [2], wherein the non-oxidizing atmosphere further contains 1 to 10 vol% of H2, and has a dew point of -40 ° C to + 20 ° C.

［４］前記鋼スラブは、質量％で、Ｃ：０．０１〜０．１５％、Ｓｉ：０．１〜１．８％、Ｍｎ：１．０〜２．７％、Ａｌ：０．０１〜１．５％、Ｐ：０．００５〜０．０２５％、Ｓ：０．０１％以下を含むことを特徴とする［２］ま［３］に記載の熱延鋼板の製造方法。   [4] The steel slab is in mass%, C: 0.01 to 0.15%, Si: 0.1 to 1.8%, Mn: 1.0 to 2.7%, Al: 0.01 The method for producing a hot-rolled steel sheet according to [2] or [3], which includes ˜1.5%, P: 0.005 to 0.025%, and S: 0.01% or less.

［５］ 前記鋼スラブは、さらに、質量％で、Ｃｒ：０．０５〜１．０％、Ｍｏ：０．０５〜１．０％、Ｎｂ：０．００５〜０．０５％、Ｔｉ：０．００５〜０．０５％、Ｃｕ：０．０５〜１．０％、Ｎｉ：０．０５〜１．０％、Ｂ：０．００１〜０．００５％から選ばれる１種以上の元素を含むことを特徴とする［４］に記載の熱延鋼板の製造方法。   [5] The steel slab is further in mass%, Cr: 0.05 to 1.0%, Mo: 0.05 to 1.0%, Nb: 0.005 to 0.05%, Ti: 0. One or more elements selected from 0.005 to 0.05%, Cu: 0.05 to 1.0%, Ni: 0.05 to 1.0%, B: 0.001 to 0.005% The method for producing a hot-rolled steel sheet according to [4].

［６］ ［４］又は［５］に記載の方法で製造した熱延鋼板を酸洗して酸化スケールを除去し、またはさらに冷間圧延し、その後、溶融亜鉛めっきすることを特徴とする溶融亜鉛めっき鋼板の製造方法。   [6] Hot-rolled steel sheet produced by the method described in [4] or [5] is pickled to remove oxide scale, or cold-rolled, and then hot-dip galvanized. Manufacturing method of galvanized steel sheet.

［７］ ［６］に記載の方法で製造した溶融亜鉛めっき鋼板をさらに合金化処理することを特徴とする溶融亜鉛めっき鋼板の製造方法。   [7] A method for producing a hot-dip galvanized steel sheet, characterized by further alloying the hot-dip galvanized steel sheet produced by the method according to [6].

本発明によれば、スラブ加熱から熱間圧延して巻き取るまでの工程を非酸化性雰囲気に制御することで、鋼板表面の酸化スケール（黒皮スケール）の生成が抑制され、表面に酸化スケールのない熱延鋼板を製造できる。この熱延鋼板は、酸化スケールを除去する酸洗工程を行わなわずに「白皮材」の熱延鋼板として出荷できる。また、本発明によれば、酸洗工程の省略及び酸減りがなくなることによる歩留まり向上が可能になる。   According to the present invention, by controlling the process from slab heating to hot rolling and winding to a non-oxidizing atmosphere, generation of oxidized scale (black skin scale) on the surface of the steel sheet is suppressed, and oxidized scale is formed on the surface. A hot-rolled steel sheet without any material can be manufactured. This hot-rolled steel sheet can be shipped as a “white skin” hot-rolled steel sheet without performing a pickling process for removing oxide scale. Further, according to the present invention, it is possible to improve the yield by eliminating the pickling process and eliminating the acid reduction.

Ｓｉ含有熱延鋼板では、Ｓｉ、Ｍｎ、Ａｌ等の易酸化性元素が内部酸化されているため、赤スケール疵の発生、テンパーカラーの発生が防止され、美麗な外観の熱延鋼板を製造できる。このＳｉ含有熱延鋼板を溶融亜鉛鋼板の母材鋼板とすると、ＣＧＬで焼鈍時にＳｉ、Ｍｎ、Ａｌ等の易酸化性元素が選択外部酸化されることがないので、Ｓｉ、Ｍｎ、Ａｌ等の易酸化性元素の選択外部酸化に起因する不めっきの発生を防止でき、また赤スケール疵に起因する外観不良も発生しないので、美麗な外観の溶融亜鉛めっき鋼板が得られる。   In Si-containing hot-rolled steel sheets, oxidizable elements such as Si, Mn, and Al are internally oxidized, so that generation of red scale wrinkles and temper color is prevented, and a hot-rolled steel sheet with a beautiful appearance can be produced. . When this Si-containing hot-rolled steel sheet is a base steel sheet of a hot-dip galvanized steel sheet, oxidizable elements such as Si, Mn, Al and the like are not selectively externally oxidized during annealing with CGL, so Si, Mn, Al, etc. Selection of easily oxidizable elements The occurrence of non-plating due to external oxidation can be prevented, and the appearance defect due to red scale wrinkles does not occur, so that a hot-dip galvanized steel sheet with a beautiful appearance can be obtained.

雰囲気制御設備を説明する概略斜視図である。It is a schematic perspective view explaining atmosphere control equipment.

以下、本発明について具体的に説明する。   Hereinafter, the present invention will be specifically described.

図１は、本発明を実施する際に使用する雰囲気制御設備の実施形態を説明する概略斜視図である。図１において、１は鋼スラブ、２はスラブ加熱炉、３は粗圧延機、４は仕上圧延機、５は巻取り機、６は熱延鋼板（ストリップ）である。鋼スラブ１は、スラブ加熱炉２で所定温度に加熱され、粗圧延機３及び仕上圧延機４で熱間圧延されて所定厚みの熱延鋼板６となり、巻取り機５で巻き取られる。   FIG. 1 is a schematic perspective view illustrating an embodiment of an atmosphere control facility used when carrying out the present invention. In FIG. 1, 1 is a steel slab, 2 is a slab heating furnace, 3 is a roughing mill, 4 is a finishing mill, 5 is a winder, and 6 is a hot-rolled steel plate (strip). The steel slab 1 is heated to a predetermined temperature by a slab heating furnace 2, hot-rolled by a rough rolling mill 3 and a finish rolling mill 4 to become a hot-rolled steel plate 6 having a predetermined thickness, and is wound by a winder 5.

従来技術では、スラブ加熱炉〜巻取り機で巻き取られるまでの工程で、大気酸化によって鋼板表面に酸化スケールが不可避的に生成する。また、Ｓｉ含有鋼スラブを使用すると、赤スケール疵が発生する問題がある。赤スケール疵とは、スラブ加熱時に何らかの原因で局所的にＦｅ酸化スケールが生成したところと、地鉄界面にＦｅ２ＳｉＯ４（ファイアライト）が生成してＦｅ酸化スケールの生成が抑制されたところが生じ、Ｆｅ酸化スケールが熱間圧延でのばされて筋状のスケール模様になった表面欠陥で、Ｓｉ含有鋼板に特有の表面欠陥である。 In the prior art, an oxide scale is inevitably generated on the surface of the steel sheet by atmospheric oxidation in a process from winding up by a slab heating furnace to a winder. Moreover, when Si containing steel slab is used, there exists a problem which a red scale wrinkle generate | occur | produces. Red scale soot is where Fe oxide scale is locally generated for some reason during slab heating, and where Fe 2 SiO 4 (firelite) is generated at the iron interface and generation of Fe oxide scale is suppressed. This is a surface defect in which the Fe oxide scale is stretched by hot rolling to form a streak scale pattern, and is a surface defect peculiar to a Si-containing steel sheet.

本発明では、図１に示すように、スラブ加熱炉２〜巻取り機５までの間は、囲いを設けて外気を遮断して酸素が混入しない設備とされ、この囲い内の雰囲気を鉄が酸化しない非酸化性雰囲気に制御する。   In the present invention, as shown in FIG. 1, a space is provided between the slab heating furnace 2 and the winder 5 so as to prevent the outside air from being mixed by providing an enclosure, and the atmosphere in the enclosure is made of iron. Control to a non-oxidizing atmosphere that does not oxidize.

鉄が酸化しない非酸化性雰囲気は、好ましくはＮ２雰囲気である。Ｈｅ、Ａｒ雰囲気でも構わないがコストアップとなるので好ましくない。 The non-oxidizing atmosphere in which iron is not oxidized is preferably an N 2 atmosphere. A He or Ar atmosphere may be used, but this is not preferable because it increases costs.

さらに、Ｎ２雰囲気にＨ２を１〜１０ｖｏｌ％含有させ、露点を−４０℃〜＋２０℃の範囲内とすることが好ましい。Ｈ２を１ｖｏｌ％以上含有させ、かつ露点を＋２０℃以下とすることで、雰囲気に万が一外気が混入して鋼表面が酸化しても生成した鉄酸化物を還元できるため、テンパーカラーのない美麗な外観を得ることができる。露点は、２０℃を超えると鉄が酸化し、−４０℃未満は制御が困難でコストアップとなるので、−４０℃〜２０℃が好ましい。Ｈ２が１ｖｏｌ％未満では鋼表面に生成した鉄酸化物を還元できなくなる。Ｈ２％は鉄酸化物還元の点からは高い方が有利であるが、１０％を超えるとコストアップになる。従って、Ｈ２は１〜１０ｖｏｌ％が好ましい。雰囲気の露点制御は、露点を上げる場合は加湿ガスを吹き込むことで、露点を下げる場合は水分を低減した乾燥Ｎ２を導入するか、雰囲気の水分を吸収除去することで可能である。 Further, by containing 1～10Vol% of H 2 in N 2 atmosphere, it is preferable that the dew point in the range of -40 ℃ ~ + 20 ℃. By containing 1 vol% or more of H 2 and having a dew point of + 20 ° C. or less, the iron oxide produced can be reduced even if outside air is mixed into the atmosphere and the steel surface is oxidized. Can be obtained. When the dew point exceeds 20 ° C., iron is oxidized. When the dew point is less than −40 ° C., control is difficult and the cost is increased. If H 2 is less than 1 vol%, the iron oxide produced on the steel surface cannot be reduced. Higher H 2 % is advantageous from the viewpoint of iron oxide reduction, but if it exceeds 10%, the cost increases. Therefore, H2 is preferably 1 to 10 vol%. The dew point of the atmosphere can be controlled by blowing a humidified gas when raising the dew point, and when reducing the dew point, introducing dry N 2 with reduced moisture or absorbing and removing moisture in the atmosphere.

雰囲気を上記のように制御する以外のスラブ加熱工程から巻取り工程まので製造条件は通常の方法でよい。   The manufacturing conditions may be normal methods from the slab heating step to the winding step other than controlling the atmosphere as described above.

なお、スラブ製造工程で形成される酸化スケールはスラブ加熱炉に装入する前に、研削等の手法で除去しておくことが必要である。   Note that the oxide scale formed in the slab manufacturing process needs to be removed by a technique such as grinding before being charged into the slab heating furnace.

本発明では、スラブ加熱工程から巻取り工程までの雰囲気を鉄が酸化しない非酸化性雰囲気に制御することで、鋼板表面の酸化スケールの生成が抑制され、巻取り機に巻き取られた鋼板表面には酸化スケールがないので、酸化スケールを除去するための酸洗を行うことなくそのまま白皮材として出荷できる表面状態が得られる。酸化スケールの生成を抑制する作用が奏される鋼スラブの成分組成は特に限定されない。   In the present invention, by controlling the atmosphere from the slab heating process to the winding process to a non-oxidizing atmosphere in which iron is not oxidized, the generation of oxide scale on the steel sheet surface is suppressed, and the steel sheet surface wound by the winder Since there is no oxide scale, a surface state can be obtained that can be shipped as a white skin material without performing pickling to remove the oxide scale. The component composition of the steel slab in which the effect | action which suppresses the production | generation of an oxide scale is show | played is not specifically limited.

鋼中にＳｉを添加したＳｉ含有鋼は、スラブ加熱時に加熱雰囲気を非酸化性雰囲気に制御してＦｅ酸化スケールが生成しないようにすると同時にスラブ表層に固溶するＳｉを内部酸化させることで、地鉄界面にＦｅ２ＳｉＯ４（ファイアライト）が生成しないため、熱延鋼板には赤スケール疵が発生しない。また、Ｍｎ、Ａｌなどの易酸化性元素が添加されている場合は、スラブ加熱時に、Ｍｎ、Ａｌなどの易酸化性元素が内部酸化される。 Si-containing steel added with Si in the steel, by controlling the heating atmosphere to a non-oxidizing atmosphere at the time of slab heating to prevent the formation of Fe oxide scale, and at the same time, internally oxidizing Si dissolved in the slab surface layer, Since Fe 2 SiO 4 (firelight) is not generated at the base iron interface, red scale defects do not occur on the hot-rolled steel sheet. When an easily oxidizable element such as Mn or Al is added, the easily oxidizable element such as Mn or Al is internally oxidized during slab heating.

Ｓｉ、Ｍｎ、Ａｌなどの易酸化性元素が内部酸化された熱延鋼板を酸洗し、または酸洗後さらに冷間圧延し、酸洗した熱延鋼板または冷間圧延した冷延鋼板をめっきの母材鋼板とすると、ＣＧＬの焼鈍過程で、内部酸化したＳｉ、Ｍｎ、Ａｌ等の易酸化性元素が鋼板表面に移動することがないので、Ｓｉ、Ｍｎ、Ａｌ等の易酸化性元素の外部酸化に起因するめっき不良が発生せず、また赤スケール疵に起因する外観不良も発生しない。   Pickled hot-rolled steel sheets that have been internally oxidized with easily oxidizable elements such as Si, Mn, Al, etc., or cold-rolled after pickling, and plated pickled hot-rolled steel sheets or cold-rolled cold-rolled steel sheets In the CGL annealing process, the oxidizable elements such as Si, Mn, and Al that are internally oxidized do not move to the steel plate surface during the annealing process of CGL. No plating defects due to external oxidation occur, and no appearance defects due to red scale defects occur.

赤スケール疵、テンパーカラーの発生を防止し、またＣＧＬでＳｉ等の易酸化性元素が外部酸化してめっき性を阻害するのを防止する点から、鋼中にＳｉを添加した鋼スラブは下記の成分組成が好ましい。なお、成分に関する「％」表示は特に断らない限り質量％を意味するものとする。   Steel slabs with Si added to the steel from the point of preventing red scale wrinkles and temper color and preventing oxidizable elements such as Si from externally oxidizing in CGL and inhibiting plating properties. The component composition is preferred. Unless otherwise specified, “%” in relation to ingredients means mass%.

Ｃ：０．０１〜０．１５％
鋼の高強度化のために０．０１％以上含有させる。０．１５％を超えると溶接性が劣化するため、上限を０．１５％に規定する。 C: 0.01 to 0.15%
In order to increase the strength of steel, it is contained by 0.01% or more. If it exceeds 0.15%, the weldability deteriorates, so the upper limit is defined as 0.15%.

Ｓｉ：０．１〜１．８％
Ｓｉは鋼の高強度化に有効な元素である。Ｓｉ量が０．１％未満では、本発明によらずとも赤スケール疵が発生しない。Ｓｉ量が１．８％を超えると、本発明法をもってしてもスラブ加熱工程でＳｉを十分に内部酸化できず、固溶Ｓｉが残存し、Ｓｉが表層で選択酸化してテンパーカラーが発生する。またＣＧＬの焼鈍過程で残存した固溶Ｓｉが選択外部酸化してめっき不良となる。そのため１．８％以下に規定する。 Si: 0.1 to 1.8%
Si is an element effective for increasing the strength of steel. If the Si amount is less than 0.1%, red scale wrinkles do not occur regardless of the present invention. If the amount of Si exceeds 1.8%, even with the method of the present invention, Si cannot be sufficiently internally oxidized in the slab heating process, so that solid solution Si remains, and Si is selectively oxidized on the surface layer to generate a temper color. To do. Further, the solid solution Si remaining in the CGL annealing process is selectively externally oxidized to cause plating defects. Therefore, it is defined as 1.8% or less.

Ｍｎ：１．０〜２．７％
鋼を高強度化するにはＭｎを添加することがより効果的である。Ｍｎ量が１．０％未満では本発明によらずとも外観不良が発生しない。Ｍｎ量が２．７％を超えると、スラブ加熱工程でＭｎを十分に内部酸化できず、固溶Ｍｎが残存し、Ｍｎが表層で選択酸化してテンパーカラーが発生する。またＣＧＬの焼鈍過程で残存した残存した固溶Ｍｎが選択外部酸化してめっき不良となる。そのため２．７％以下に規定する。 Mn: 1.0 to 2.7%
In order to increase the strength of steel, it is more effective to add Mn. If the amount of Mn is less than 1.0%, the appearance defect does not occur regardless of the present invention. If the amount of Mn exceeds 2.7%, Mn cannot be sufficiently internally oxidized in the slab heating process, so that solid solution Mn remains, Mn is selectively oxidized on the surface layer, and a temper color is generated. Further, the remaining solid solution Mn remaining in the CGL annealing process is selectively externally oxidized to cause plating failure. Therefore, it is specified as 2.7% or less.

Ａｌ：０．０１〜１．５％
下限は不可避的に混入する量である。Ａｌは残留γ相安定化効果があり、機械特性向上のために添加することができる。そのためには、０．１％以上含有させることが好ましい。Ａｌ量が１．５％を超えると、スラブ加熱工程でＡｌを十分に内部酸化できず、固溶Ａｌが残存し、Ａｌが表層で選択酸化してテンパーカラーが発生する。またＣＧＬの焼鈍過程で残存した固溶Ａｌが選択外部酸化してめっき不良となる。そのため１．５％以下に規定する。 Al: 0.01 to 1.5%
The lower limit is an amount inevitably mixed. Al has an effect of stabilizing the residual γ phase and can be added to improve mechanical properties. For that purpose, it is preferable to make it contain 0.1% or more. When the amount of Al exceeds 1.5%, Al cannot be sufficiently oxidized internally in the slab heating process, so that solid solution Al remains, Al is selectively oxidized on the surface layer, and a temper color is generated. Further, the solid solution Al remaining in the annealing process of CGL is selectively externally oxidized, resulting in poor plating. Therefore, it is specified to be 1.5% or less.

Ｐ：０．００５〜０．０２５％
Ｐは不可避的に含有される元素であり、一方セメンタイトの析出を遅延させ変態の進行を遅らせるため、０．００５％以上含有させる。０．０２５％を超えると、溶接性が劣化するだけでなく、スラブ加熱工程で内部酸化しきれずにＣＧＬの焼鈍過程で酸化して表面品質が劣化するため、０．０２５％以下に規定する。 P: 0.005-0.025%
P is an element inevitably contained. On the other hand, P is contained in an amount of 0.005% or more in order to delay the precipitation of cementite and delay the progress of transformation. If it exceeds 0.025%, not only the weldability is deteriorated, but also the internal quality is not completely oxidized in the slab heating step, but the surface quality is deteriorated by oxidation in the annealing process of CGL.

Ｓ：０．０１％以下
Ｓは不可避的に含有される元素である。下限は規定しないが、多量に含有されると溶接性が劣化するだけでなく焼鈍時にＳが表面に析出して外観が劣化するため０．０１％以下に規定する。 S: 0.01% or less S is an element inevitably contained. The lower limit is not specified, but if it is contained in a large amount, not only the weldability deteriorates but also S precipitates on the surface during annealing and the appearance deteriorates, so it is specified to be 0.01% or less.

残部はＦｅおよび不可避的不純物である。なお、これらの成分元素に加えて、鋼板の機械特性を上昇させるために、必要であれば、Ｃｒ：０．０５〜１．０％、Ｍｏ：０．０５〜１．０％、Ｎｂ：０．００５〜０．０５％、Ｔｉ：０．００５〜０．０５％、Ｃｕ：０．０５〜１．０％、Ｎｉ：０．０５〜１．０％、Ｂ：０．００１〜０．００５％から選ばれる１種以上の元素を添加しても良い。なお、Ｃｒ、Ｍｏ、Ｎｂ、Ｃｕ、Ｎｉは単独もしくは２種以上の複合添加でＳｉの内部酸化を促進し、選択外部酸化を抑制する効果を有するため、これら元素は機械特性改善のためでなく、Ｓｉの内部酸化を促進させるために添加しても良い。   The balance is Fe and inevitable impurities. In addition to these component elements, Cr: 0.05 to 1.0%, Mo: 0.05 to 1.0%, Nb: 0 if necessary to increase the mechanical properties of the steel sheet. 0.005-0.05%, Ti: 0.005-0.05%, Cu: 0.05-1.0%, Ni: 0.05-1.0%, B: 0.001-0.005 One or more elements selected from% may be added. Note that Cr, Mo, Nb, Cu, and Ni have the effect of accelerating the internal oxidation of Si and suppressing the selective external oxidation when added alone or in combination of two or more, so these elements are not for improving mechanical properties. , May be added to promote internal oxidation of Si.

上記元素を添加する場合の限定理由を説明する。   The reason for limitation when adding the above elements will be described.

Ｃｒは０．０５％未満では焼き入れ性やＳｉの内部酸化を促進する効果が得られにくく、１．０％超えではかえってＣｒが選択外部酸化するため、めっき性が劣化する。そのため、Ｃｒは０．０５〜１．０％に規定する。   If Cr is less than 0.05%, it is difficult to obtain the effect of promoting hardenability and internal oxidation of Si, and if it exceeds 1.0%, Cr is selectively externally oxidized, so that the plating property is deteriorated. Therefore, Cr is specified to be 0.05 to 1.0%.

Ｍｏは０．０５％未満では強度調整の効果やＮｂ、Ｎｉ、Ｃｕとの複合添加時におけるＳｉの内部酸化を促進する効果が得られにくく、１．０％超えではコストアップを招く。そのため、Ｍｏは０．０５〜１．０％に規定する。   If Mo is less than 0.05%, it is difficult to obtain the effect of adjusting the strength and the effect of promoting internal oxidation of Si at the time of composite addition with Nb, Ni, and Cu, and if it exceeds 1.0%, the cost increases. Therefore, Mo is specified to be 0.05 to 1.0%.

Ｎｂは０．００５％未満では強度調整の効果やＭｏとの複合添加時におけるＳｉの内部酸化を促進する効果が得られにくく、０．０５％超えではコストアップを招く。そのため、Ｎｂは０．００５〜０．０５％に規定する。   If Nb is less than 0.005%, the effect of adjusting the strength and the effect of promoting the internal oxidation of Si at the time of composite addition with Mo are difficult to obtain, and if it exceeds 0.05%, the cost increases. Therefore, Nb is specified to be 0.005 to 0.05%.

Ｔｉは０．００５％未満では強度調整の効果が得られにくく、０．０５％超えではめっき性の劣化を招く。そのため、Ｔｉは０．００５〜０．０５％に規定する。   When Ti is less than 0.005%, the effect of adjusting the strength is difficult to obtain, and when it exceeds 0.05%, the plating property is deteriorated. Therefore, Ti is specified to be 0.005 to 0.05%.

Ｃｕは０．０５％未満では残留γ相形成促進効果やＮｉやＭｏとの複合添加時におけるＳｉの内部酸化を促進する効果が得られにくく、１．０％超えではコストアップを招く。そのため、Ｃｕは０．０５〜１．０％に規定する。   If Cu is less than 0.05%, it is difficult to obtain the effect of promoting the formation of residual γ phase and the effect of promoting the internal oxidation of Si at the time of composite addition with Ni or Mo, and if it exceeds 1.0%, the cost increases. Therefore, Cu is specified to be 0.05 to 1.0%.

Ｎｉは０．０５％未満では残留γ相形成促進効果やＣｕやＭｏとの複合添加時におけるＳｉの内部酸化を促進する効果が得られにくく、１．０％超えではコストアップを招く。そのため、Ｎｉは０．０５〜１．０％に規定する。   If Ni is less than 0.05%, it is difficult to obtain the effect of promoting the formation of residual γ phase and the effect of promoting the internal oxidation of Si at the time of composite addition with Cu or Mo, and if it exceeds 1.0%, the cost increases. Therefore, Ni is specified to be 0.05 to 1.0%.

Ｂは０．００１％未満では焼き入れ促進効果が得られにくく、０．００５％超えではめっき性が劣化する。そのため、Ｂは０．００１〜０．００５％に規定する。
但し言うまでもなく機械的特性改善上添加する必要がないと判断される場合は添加する必要はない。 When B is less than 0.001%, it is difficult to obtain the effect of promoting quenching, and when it exceeds 0.005%, the plateability deteriorates. Therefore, B is specified to be 0.001 to 0.005%.
However, needless to say, it is not necessary to add when it is judged that it is not necessary to improve the mechanical properties.

上記の成分組成を有する鋼スラブを用いて熱延鋼板を製造する際に、スラブ加熱工程から巻取り工程までを、外気を遮断して酸素が混入しない非酸化性の制御雰囲気下におくことで、鋼板表層のＳｉ、Ｍｎ、Ａｌ等の易酸化性元素を内部酸化させることができる。すなわち、酸素が混入するとＦｅより酸化し易いＳｉ、Ｍｎ、Ａｌのような易酸化性元素は選択外部酸化されて内部酸化しないが、酸素が混入しない非酸化性雰囲気にすると、雰囲気中のＨ２Ｏから供給されたＯが酸素供給源となり、Ｆｅが酸化せずに鋼中に固溶しているＳｉ、Ｍｎ、Ａｌのような易酸化性元素が内部酸化される。その結果、赤スケール疵、テンパーカラーの発生を防止できる。 When manufacturing a hot-rolled steel sheet using a steel slab having the above composition, by placing the slab heating process through the winding process in a non-oxidizing control atmosphere that blocks outside air and does not mix oxygen. In addition, oxidizable elements such as Si, Mn, and Al on the steel sheet surface layer can be internally oxidized. That is, oxidizable elements such as Si, Mn, and Al, which are more easily oxidized than Fe when oxygen is mixed, are selectively externally oxidized and are not internally oxidized. However, if a non-oxidizing atmosphere in which oxygen is not mixed is used, H 2 in the atmosphere O supplied from O serves as an oxygen supply source, and oxidizable elements such as Si, Mn, and Al dissolved in the steel without oxidizing Fe are internally oxidized. As a result, generation of red scale wrinkles and temper colors can be prevented.

巻取り機に巻き取った熱延鋼板は、表面に熱間圧延工程の途中で生成した極薄い酸化皮膜が存在するので、めっきの母材鋼板とするときは、熱間圧延工程の後、通常の酸洗処理によって酸洗し、表面の酸化皮膜を完全に除去する。酸洗した熱延鋼板、または酸洗した熱延鋼板を常法で冷間圧延した冷延鋼板をめっきの母材鋼板とし、この母材鋼板をＣＧＬに装入する。   Since the hot-rolled steel sheet wound up by the winder has a very thin oxide film formed on the surface during the hot rolling process, when it is used as a base metal sheet for plating, it is usually after the hot rolling process. The pickling treatment is performed to completely remove the oxide film on the surface. A pickled hot-rolled steel sheet or a cold-rolled steel sheet obtained by cold rolling a pickled hot-rolled steel sheet by a conventional method is used as a base steel sheet for plating, and the base steel sheet is charged into the CGL.

前記の母材鋼板（Ｓｉ含有高強度鋼板）は、熱間圧延工程でＳｉ、Ｍｎ、Ａｌのような易酸化性元素が内部酸化されており、赤スケール疵もないので、ＣＧＬでは、加熱炉の形式に係わらず、ＤＦＦ（直火型）、ＮＯＦ（無酸化型）、オールラジアントチューブ型のいずれの加熱炉で加熱しても、内部酸化したＳｉ、Ｍｎ、Ａｌ等の易酸化性元素の酸化物は鋼板表面に拡散しないので、良好なめっき性を確保でき、また赤スケール疵に起因する外観不良がなく、良好な外観が得られる。ＣＧＬの加熱炉の条件は通常の条件でよい。   The base steel plate (Si-containing high-strength steel plate) has an internal oxidation of easily oxidizable elements such as Si, Mn, and Al in the hot rolling process, and there is no red scale soot. Regardless of the type, any of the oxidizable elements such as Si, Mn, Al, etc. that are internally oxidized even if heated in any heating furnace of DFF (direct flame type), NOF (non-oxidation type), or all radiant tube type Since the oxide does not diffuse on the surface of the steel sheet, good plating properties can be ensured, and there is no poor appearance due to red scale wrinkles, and a good appearance can be obtained. The conditions for the CGL heating furnace may be normal conditions.

めっき付着量は片面あたり２０〜１２０ｇ／ｍ２が好ましい。２０ｇ／ｍ２未満は耐食性の確保が困難になり、１２０ｇ／ｍ２超えは耐めっき剥離性が劣化する。また合金化溶融亜鉛めっき鋼板はめっき層のＦｅ含有量は７〜１５％が好ましい。７％未満は合金化ムラの発生、耐フレーキング性の劣化が起こり、１５％超えは耐めっき剥離性が劣化する。 The plating adhesion amount is preferably 20 to 120 g / m 2 per side. If it is less than 20 g / m 2, it becomes difficult to ensure corrosion resistance, and if it exceeds 120 g / m 2, the plating peel resistance deteriorates. The alloyed hot-dip galvanized steel sheet preferably has a Fe content of 7 to 15% in the plating layer. If it is less than 7%, unevenness in alloying occurs and flaking resistance deteriorates, and if it exceeds 15%, the plating peel resistance deteriorates.

溶融亜鉛めっき条件、合金化処理条件は通常の方法でよい。   The hot dip galvanizing conditions and alloying treatment conditions may be ordinary methods.

表１に示す化学成分と残部がＦｅ及び不可避的不純物からなる厚さ２００ｍｍの軟鋼スラブを準備し、下記の条件でスラブ加熱工程〜巻取り工程までを行う熱延鋼板製造のラボ試験を行った。すなわち、スラブを加熱炉で加熱した後、粗圧延機および仕上圧延機で圧延を行い厚さ３ｍｍのストリップとし、巻取り機で巻き取った。加熱炉のスラブ加熱温度は１２５０℃、仕上圧延の仕上げ温度は９００℃、巻取り温度は５５０℃とした。加熱炉〜巻取り機までの雰囲気を表２に記載の雰囲気に制御した。巻き取ったコイルを冷却した後巻き戻し、外観を評価した。外観は、色調を目視観察し、テンパーカラーの発生がなく、従来の白皮材と同等の外観を有するものを「白色」、従来の黒皮材と同等の黒色の外観をするものを「黒色」、テンパーカラーが発生し、薄褐色に変色した外観を有するものを「薄褐色」と評価した。評価が「白色」の熱延鋼板は、スケール除去の酸洗を行うことなく白皮材として出荷可能な外観である。評価が「薄褐色」、「黒色」の熱延鋼板は、白皮材として出荷するには、スケール除去の酸洗を行う必要がある外観である。   A 200 mm thick mild steel slab consisting of the chemical components shown in Table 1 and the balance consisting of Fe and inevitable impurities was prepared, and a lab test for hot-rolled steel sheet manufacturing was carried out under the following conditions from the slab heating step to the winding step. . That is, after the slab was heated in a heating furnace, it was rolled with a roughing mill and a finishing mill to form a strip having a thickness of 3 mm, and wound with a winder. The slab heating temperature of the heating furnace was 1250 ° C., the finishing temperature of finish rolling was 900 ° C., and the winding temperature was 550 ° C. The atmosphere from the heating furnace to the winder was controlled to the atmosphere shown in Table 2. After winding the coil, it was rewound and the appearance was evaluated. Appearance is observing the color tone, temper color is not generated, “white” is the one that has the same appearance as the conventional white skin material, and “black” is the one that has the same black appearance as the conventional black skin material. "A temper color was generated, and the appearance having a pale brown color was evaluated as" light brown ". The hot-rolled steel sheet having an evaluation of “white” has an appearance that can be shipped as a white skin material without performing pickling for removing the scale. The hot-rolled steel sheets with “light brown” and “black” evaluations have an appearance that needs to be pickled for descaling in order to ship as a white skin material.

Figure 2011224584
Figure 2011224584

Figure 2011224584
Figure 2011224584

結果を表２に示す。表２から明らかなように、雰囲気を本発明範囲内に制御した発明例の熱延鋼板は、そのまま白皮材として出荷できる美麗な外観が得られている。これに対して、雰囲気が本発明範囲外の比較例の熱延鋼板は、そのまま白皮材として出荷できる美麗な外観が得られていない。   The results are shown in Table 2. As is apparent from Table 2, the hot rolled steel sheet of the inventive example in which the atmosphere is controlled within the scope of the present invention has a beautiful appearance that can be shipped as a white skin material as it is. On the other hand, the hot rolled steel sheet of the comparative example whose atmosphere is outside the scope of the present invention does not have a beautiful appearance that can be shipped as a white skin material as it is.

Ｓｉ含有鋼スラブを用いて熱延鋼板の製造実験を行った結果を説明する。
表３に示す化学成分と残部がＦｅ及び不可避的不純物からなる厚さ３００ｍｍの鋼スラブを準備し、下記の条件でスラブ加熱工程〜巻取り工程までを行う熱延鋼板製造のラボ試験を行った。すなわち、スラブを加熱炉で加熱した後、粗圧延機及び仕上圧延機で圧延を行い厚さ３ｍｍのストリップとし、巻取り機で巻き取った。加熱炉のスラブ加熱温度は１２５０℃、仕上圧延の仕上げ温度は９００℃、巻取り温度は５５０℃とした。加熱炉〜巻取り機までの雰囲気を表４に記載の雰囲気に制御した。巻き取ったコイルを冷却した後巻き戻し、外観を目視観察し、色調と赤スケール疵の有無を評価した。色調は実施例１と同様の評価を行った。白皮材として出荷可能な外観であるか否かの判断基準も実施例１と同様である。 The result of having conducted the manufacture experiment of a hot-rolled steel plate using Si content steel slab is explained.
A steel slab having a thickness of 300 mm consisting of the chemical components shown in Table 3 and the balance consisting of Fe and unavoidable impurities was prepared, and a laboratory test for hot-rolled steel sheet manufacturing was performed under the following conditions from the slab heating step to the winding step. . That is, after the slab was heated in a heating furnace, the slab was rolled with a roughing mill and a finishing mill to form a strip having a thickness of 3 mm and wound with a winder. The slab heating temperature of the heating furnace was 1250 ° C., the finishing temperature of finish rolling was 900 ° C., and the winding temperature was 550 ° C. The atmosphere from the heating furnace to the winder was controlled to the atmosphere shown in Table 4. After winding the coil, it was rewound and the appearance was visually observed to evaluate the color tone and the presence of red scale wrinkles. The color tone was evaluated in the same manner as in Example 1. The criteria for determining whether or not the appearance can be shipped as a white skin material is the same as in the first embodiment.

Figure 2011224584
Figure 2011224584

Figure 2011224584
Figure 2011224584

結果を表４に示す。表４から明らかなように、本発明の請求項４又は請求項５で規定する鋼スラブを用いて本発明法で雰囲気制御をして熱延鋼板を製造した発明例の熱延鋼板は、そのまま白皮材として出荷できる程度の美麗な外観が得られており、赤スケール疵の発生もない。これに対して、雰囲気が本発明範囲外の比較例の熱延鋼板は、そのまま白皮材として出荷できる美麗な外観が得られていない。   The results are shown in Table 4. As is apparent from Table 4, the hot-rolled steel sheet of the invention example in which a hot-rolled steel sheet was manufactured by controlling the atmosphere by the method of the present invention using the steel slab defined in claim 4 or claim 5 of the present invention was used as it was. A beautiful appearance that can be shipped as a white skin material is obtained, and there is no occurrence of red scale wrinkles. On the other hand, the hot rolled steel sheet of the comparative example whose atmosphere is outside the scope of the present invention does not have a beautiful appearance that can be shipped as a white skin material as it is.

実施例２で作成した熱延鋼板を酸洗して熱間圧延で生成した酸化皮膜を除去し、一部は酸洗ままの熱延鋼板とし、一部は酸洗後さらに圧下率５０％で冷間圧延を施して冷延鋼板とした。前記で作製した熱延鋼板と冷延鋼板を、オールラジアント型ＣＧＬシミュレータで、８５０℃で焼鈍した後溶融亜鉛めっきし、一部はさらに合金化処理した。溶融亜鉛めっき後合金化処理を行う溶融亜鉛めっき鋼板（ＧＡ）は０．１４％Ａｌ含有Ｚｎ浴、溶融亜鉛めっき後合金化処理を行わない溶融亜鉛めっき鋼板（ＧＩ）は０．１８％Ａｌ含有Ｚｎ浴を用いた。めっき付着量はガスワイピングにより片面あたり５０ｇ／ｍ２に調節した。溶融亜鉛めっき方法、合金化処理方法は通常の方法で実施した。 The hot-rolled steel sheet prepared in Example 2 was pickled and the oxide film formed by hot rolling was removed, and part of the hot-rolled steel sheet was pickled as it was, and part of the hot-rolled steel sheet was pickled at 50% after pickling. Cold rolling was performed to obtain a cold rolled steel sheet. The hot-rolled steel sheet and cold-rolled steel sheet produced above were annealed at 850 ° C. with an all-radiant CGL simulator, and then hot-dip galvanized, and a part thereof was further alloyed. Hot-dip galvanized steel sheet (GA) that is alloyed after hot dip galvanizing Zn bath containing 0.14% Al Hot-dip galvanized steel sheet (GI) that is not subjected to alloying treatment after hot dip galvanizing contains 0.18% Al A Zn bath was used. The plating adhesion amount was adjusted to 50 g / m 2 per side by gas wiping. The hot dip galvanizing method and the alloying method were carried out by ordinary methods.

前記で製造しためっき鋼板の外観を観察し、赤スケール疵に起因する欠陥の発生有無、不めっきの有無を観察し、赤スケール疵に起因する欠陥、不めっきの少なくとも一方が認められるものを外観が不良、いずれも認められないものを外観が美麗と評価した。   Observe the appearance of the plated steel plate produced above, observe the presence or absence of defects due to red scale wrinkles, the presence or absence of non-plating, and the appearance with at least one of defects due to red scale wrinkles and non-plating is observed However, the appearance was evaluated as being beautiful.

Figure 2011224584
Figure 2011224584

調査結果を表５に示す。表５から明らかなように、本発明の請求項４又は請求項５で規定する鋼スラブを用いて本発明法で製造された発明例の溶融亜鉛めっき鋼板は、Ｓｉ、Ｍｎ、Ａｌ添加鋼であっても良好な外観のめっき鋼板が得られている。一方、本発明の請求項４又は請求項５で規定する成分組成範囲を外れる鋼スラブを使用して製造した溶融亜鉛めっき鋼板、または本発明法を外れる雰囲気条件で製造された溶融亜鉛めっき鋼板は、赤スケール疵または不めっきが発生し、外観が劣る。   The survey results are shown in Table 5. As apparent from Table 5, the hot-dip galvanized steel sheet of the inventive example manufactured by the method of the present invention using the steel slab defined in claim 4 or claim 5 of the present invention is Si, Mn, Al-added steel. Even if it exists, the plated steel plate of a favorable external appearance is obtained. On the other hand, a hot-dip galvanized steel sheet manufactured using a steel slab that deviates from the component composition range specified in claim 4 or claim 5 of the present invention, or a hot-dip galvanized steel sheet manufactured under an atmospheric condition that deviates from the method of the present invention, , Red scale wrinkles or non-plating occurs, and the appearance is poor.

本発明によれば、酸化スケールを除去する酸洗工程を行わなくても「白皮材」として出荷できる熱延鋼板を製造することができる。Ｓｉ含有熱延鋼板では、Ｓｉ、Ｍｎ、Ａｌ等の易酸化性元素が内部酸化されているため、赤スケール疵の発生、テンパーカラーの発生のない美麗な外観のＳｉ含有熱延鋼板を製造することができる。このＳｉ含有熱延鋼板を溶融亜鉛鋼板の母材鋼板とすると、ＣＧＬの焼鈍時にＳｉ、Ｍｎ、Ａｌ等の易酸化性元素が選択外部酸化されることがなくなるので、Ｓｉ、Ｍｎ、Ａｌ等の易酸化性元素の選択外部酸化に起因する不めっきの発生を防止でき、また赤スケール疵に起因する外観不良がなく、美麗な外観の溶融亜鉛めっき鋼板を製造することができる。   According to the present invention, it is possible to manufacture a hot-rolled steel sheet that can be shipped as a “white skin material” without performing a pickling process for removing oxide scale. In Si-containing hot-rolled steel sheets, oxidizable elements such as Si, Mn, Al, etc. are internally oxidized, so that a beautiful-looking Si-containing hot-rolled steel sheet that does not generate red scale wrinkles or temper color is produced. be able to. When this Si-containing hot-rolled steel sheet is used as a base steel sheet of a hot-dip galvanized steel sheet, oxidizable elements such as Si, Mn, and Al are not selectively externally oxidized during CGL annealing. Selection of an easily oxidizable element It is possible to prevent the occurrence of non-plating due to external oxidation, and it is possible to produce a hot-dip galvanized steel sheet having a beautiful appearance without appearance defects due to red scale wrinkles.

１ スラブ
２ スラブ加熱炉
３ 粗圧延機
４ 仕上げ圧延機
５ 巻取り機
６ 熱延鋼板 DESCRIPTION OF SYMBOLS 1 Slab 2 Slab heating furnace 3 Rough rolling mill 4 Finish rolling mill 5 Winding machine 6 Hot-rolled steel sheet

Claims (7)

鋼スラブをスラブ加熱炉にて加熱するスラブ加熱工程、加熱した鋼スラブを粗圧延機及び仕上圧延機で熱間圧延してストリップとする工程、ストリップを巻取り機に巻き取る巻取り工程を行う熱延鋼板の製造方法において、スラブ加熱工程〜巻取り工程までの工程の雰囲気を非酸化性雰囲気にすることを特徴とする熱延鋼板の製造方法。   A slab heating process in which a steel slab is heated in a slab heating furnace, a process in which the heated steel slab is hot-rolled with a roughing mill and a finishing mill to form a strip, and a winding process in which the strip is wound around a winder are performed. In the manufacturing method of a hot-rolled steel sheet, the process atmosphere from a slab heating process to a winding process is made into a non-oxidizing atmosphere, The manufacturing method of the hot-rolled steel sheet characterized by the above-mentioned. 前記非酸化性雰囲気はＮ２雰囲気であることを特徴とする請求項１に記載の熱延鋼板の製造方法。 The method for producing a hot-rolled steel sheet according to claim 1, wherein the non-oxidizing atmosphere is an N 2 atmosphere. 前記非酸化性雰囲気は、さらにＨ２を１〜１０ｖｏｌ％含み、かつ露点が−４０℃〜＋２０℃であることを特徴とする請求項２に記載の熱延鋼板の製造方法。 The method for producing a hot-rolled steel sheet according to claim 2, wherein the non-oxidizing atmosphere further contains 1 to 10 vol% of H2, and has a dew point of -40 ° C to + 20 ° C. 前記鋼スラブは、質量％で、Ｃ：０．０１〜０．１５％、Ｓｉ：０．１〜１．８％、Ｍｎ：１．０〜２．７％、Ａｌ：０．０１〜１．５％、Ｐ：０．００５〜０．０２５％、Ｓ：０．０１％以下を含むことを特徴とする請求項２または３に記載の熱延鋼板の製造方法。   The said steel slab is the mass%, C: 0.01-0.15%, Si: 0.1-1.8%, Mn: 1.0-2.7%, Al: 0.01-1. The method for producing a hot-rolled steel sheet according to claim 2 or 3, comprising 5%, P: 0.005 to 0.025%, and S: 0.01% or less. 前記鋼スラブは、さらに、質量％で、Ｃｒ：０．０５〜１．０％、Ｍｏ：０．０５〜１．０％、Ｎｂ：０．００５〜０．０５％、Ｔｉ：０．００５〜０．０５％、Ｃｕ：０．０５〜１．０％、Ｎｉ：０．０５〜１．０％、Ｂ：０．００１〜０．００５％から選ばれる１種以上の元素を含むことを特徴とする請求項４に記載の熱延鋼板の製造方法。   The steel slab is further in mass%, Cr: 0.05 to 1.0%, Mo: 0.05 to 1.0%, Nb: 0.005 to 0.05%, Ti: 0.005. It contains one or more elements selected from 0.05%, Cu: 0.05 to 1.0%, Ni: 0.05 to 1.0%, B: 0.001 to 0.005% The method for producing a hot-rolled steel sheet according to claim 4. 請求項４又は５に記載の方法で製造した熱延鋼板を酸洗して酸化スケールを除去し、またはさらに冷間圧延し、その後、溶融亜鉛めっきすることを特徴とする溶融亜鉛めっき鋼板の製造方法。   The hot-rolled steel sheet manufactured by the method according to claim 4 or 5 is pickled to remove the oxide scale, or further cold-rolled, and then hot-dip galvanized to produce a hot-dip galvanized steel sheet Method. 請求項６に記載の方法で製造した溶融亜鉛めっき鋼板をさらに合金化処理することを特徴とする溶融亜鉛めっき鋼板の製造方法。   A method for producing a hot dip galvanized steel sheet, characterized by further alloying the hot dip galvanized steel sheet produced by the method according to claim 6.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101490563B1 (en) 2012-12-21 2015-02-05 주식회사 포스코 Ultra-high strenth galvinized steel sheet having execellent galvanized properties and method for manufacturing the same
JP2017002366A (en) * 2015-06-11 2017-01-05 新日鐵住金株式会社 Hot rolled steel sheet excellent in cold workability and manufacturing method thereof
RU2618958C2 (en) * 2012-03-23 2017-05-11 Зальцгиттер Флахшталь Гмбх Improved steel without slag, method of manufacturing details without scale of this steel and method of obtaining hot-rolled steel strip
JP2018503740A (en) * 2014-12-22 2018-02-08 ポスコＰｏｓｃｏ Hot-rolled steel sheet for high-strength galvanized steel sheet with excellent surface quality and manufacturing method thereof

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6111522B2 (en) * 2012-03-02 2017-04-12 Ｊｆｅスチール株式会社 High-strength hot-dip galvanized steel sheet and manufacturing method thereof
JP5884202B2 (en) * 2013-01-24 2016-03-15 Ｊｆｅスチール株式会社 Hot-rolled steel sheet for high-strength line pipe
KR20150025952A (en) * 2013-08-30 2015-03-11 현대제철 주식회사 High strength plated hot-rolled steel sheet and method of manufacturing the same
CN103978035B (en) * 2014-04-28 2016-09-07 雷光瑞 The processing method of hot-rolled steel
KR101672102B1 (en) 2014-12-22 2016-11-02 주식회사 포스코 Hot rolled steel sheet for hot galvanized iron having high surface quality and high strength, and method for producing the same
CN107419177A (en) * 2017-08-07 2017-12-01 武汉钢铁有限公司 Tensile strength for automobile is the hot rolling acid-cleaning steel and its manufacture method of 540MPa levels
CN109881096A (en) * 2019-03-15 2019-06-14 本钢板材股份有限公司 A kind of 800MPa grades of one-side electroplating zinc phase-change induced plastic steel plate and preparation method thereof
CN115608802A (en) * 2022-09-30 2023-01-17 攀钢集团攀枝花钢铁研究院有限公司 Hot working method of boron-containing steel acid pickling plate

Family Cites Families (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1968442A (en) * 1931-09-05 1934-07-31 Emerson L Clark Process of heating and rolling steel in an inert gas inclosure
US2310451A (en) * 1940-06-17 1943-02-09 American Rolling Mill Co Process of coating metal articles with molten metal and of preparing metal articles for hot coating
US4296919A (en) * 1980-08-13 1981-10-27 Nippon Steel Corporation Apparatus for continuously producing a high strength dual-phase steel strip or sheet
JPS5832506A (en) * 1981-08-21 1983-02-25 Kawasaki Steel Corp Slightly oxidative hot rolling method
JPS5997710A (en) * 1982-11-29 1984-06-05 Kawasaki Steel Corp Cooling method of hot rolled steel strip
JPS61123403A (en) * 1984-11-19 1986-06-11 Kawasaki Steel Corp Method for suppressing scale formation of hot-rolled steel strip
FR2664617B1 (en) * 1990-07-16 1993-08-06 Lorraine Laminage PROCESS FOR COATING ALUMINUM BY HOT TEMPERING OF A STEEL STRIP AND STEEL STRIP OBTAINED BY THIS PROCESS.
JPH04266401A (en) * 1991-02-20 1992-09-22 Sumitomo Metal Ind Ltd Manufacture of hot rolled steel sheet with thin scale
CN1041641C (en) * 1993-06-29 1999-01-13 日本钢管株式会社 Surface treated steel sheet and method therefor
JPH07126747A (en) * 1993-11-05 1995-05-16 Sumitomo Metal Ind Ltd Production of si-containing steel plate excellent in hot dip galvanizing suitability
TW275649B (en) * 1993-11-22 1996-05-11 Nippon Steel Corp
CN1044585C (en) * 1994-07-08 1999-08-11 孟庆连 Method for continuously making metal composite sheet or composite coil
JPH08309406A (en) * 1995-05-15 1996-11-26 Hitachi Ltd Continuous casting direct-coupled hot rolling system
US5948121A (en) * 1995-11-30 1999-09-07 Novo Nordisk A/S Laccases with improved dyeing properties
BE1011131A6 (en) * 1997-04-28 1999-05-04 Centre Rech Metallurgique Method of coating a steel strip by hot-dip galvanising
CN1117884C (en) * 1998-09-29 2003-08-13 川崎制铁株式会社 High strength thin steel sheet, high strength alloyed hot-dip zinc-coated steel sheet, and method for producing them
JP2001140021A (en) * 1999-11-18 2001-05-22 Kawasaki Steel Corp Method of manufacturing high strength galvanized steel sheet and galvanized steel sheet excellent in coating stickiness
EP1227167B1 (en) * 2000-01-24 2006-01-18 JFE Steel Corporation Hot dip zinc plated steel sheet and method for producing the same
JP2002192309A (en) * 2000-12-28 2002-07-10 Ishikawajima Harima Heavy Ind Co Ltd Equipment for manufacturing thin steel plate and using method thereof
WO2002057503A1 (en) * 2001-01-19 2002-07-25 Kawasaki Steel Corporation Grain-oriented magnetic steel sheet having no undercoat film comprising forsterite as primary component and having good magnetic characteristics
JP4085583B2 (en) * 2001-02-27 2008-05-14 Ｊｆｅスチール株式会社 High-strength cold-rolled galvanized steel sheet and method for producing the same
JP4718782B2 (en) 2003-02-06 2011-07-06 新日本製鐵株式会社 Alloyed hot-dip galvanized steel sheet and method for producing the same
JP3997931B2 (en) * 2003-03-04 2007-10-24 Ｊｆｅスチール株式会社 Method for producing high-tensile hot-dip galvanized steel sheet
JP4464720B2 (en) 2003-04-10 2010-05-19 新日本製鐵株式会社 High-strength hot-dip galvanized steel sheet and manufacturing method thereof
JP4192051B2 (en) * 2003-08-19 2008-12-03 新日本製鐵株式会社 Manufacturing method and equipment for high-strength galvannealed steel sheet
WO2006038736A1 (en) * 2004-10-07 2006-04-13 Jfe Steel Corporation Hot dip zinc plated steel sheet and method for production thereof
JP4741376B2 (en) 2005-01-31 2011-08-03 新日本製鐵株式会社 High-strength galvannealed steel sheet with good appearance, manufacturing method and manufacturing equipment thereof
BRPI0610540B1 (en) * 2005-04-20 2017-01-17 Nippon Steel & Sumitomo Metal Corp Annealed steel sheet production method after hot dip galvanization
BRPI0617390B1 (en) * 2005-10-14 2017-12-05 Nippon Steel & Sumitomo Metal Corporation METHOD OF CONTINUOUS CUTTING AND COATING BY HOT IMMERSION AND CONTINUOUS CUTTING AND COATING SYSTEM BY HOT IMMERSION OF STEEL PLATES CONTAINING Si
JP4964494B2 (en) * 2006-05-09 2012-06-27 新日本製鐵株式会社 High-strength steel sheet excellent in hole expansibility and formability and method for producing the same
JP5315795B2 (en) * 2008-05-30 2013-10-16 Ｊｆｅスチール株式会社 High-strength hot-dip galvanized steel sheet, high-strength alloyed hot-dip galvanized steel sheet, and a method for producing the same

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2618958C2 (en) * 2012-03-23 2017-05-11 Зальцгиттер Флахшталь Гмбх Improved steel without slag, method of manufacturing details without scale of this steel and method of obtaining hot-rolled steel strip
KR101490563B1 (en) 2012-12-21 2015-02-05 주식회사 포스코 Ultra-high strenth galvinized steel sheet having execellent galvanized properties and method for manufacturing the same
JP2018503740A (en) * 2014-12-22 2018-02-08 ポスコＰｏｓｃｏ Hot-rolled steel sheet for high-strength galvanized steel sheet with excellent surface quality and manufacturing method thereof
JP2017002366A (en) * 2015-06-11 2017-01-05 新日鐵住金株式会社 Hot rolled steel sheet excellent in cold workability and manufacturing method thereof

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CA2794658A1 (en) 2011-10-20
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