JP5354165B2 - Method for producing galvanized steel sheet - Google Patents

Method for producing galvanized steel sheet Download PDF

Info

Publication number
JP5354165B2
JP5354165B2 JP2008319131A JP2008319131A JP5354165B2 JP 5354165 B2 JP5354165 B2 JP 5354165B2 JP 2008319131 A JP2008319131 A JP 2008319131A JP 2008319131 A JP2008319131 A JP 2008319131A JP 5354165 B2 JP5354165 B2 JP 5354165B2
Authority
JP
Japan
Prior art keywords
steel sheet
zinc
aqueous solution
galvanized steel
oxide layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2008319131A
Other languages
Japanese (ja)
Other versions
JP2009203547A (en
Inventor
洋一 牧水
浩志 梶山
栄 藤田
直人 吉見
雅彦 多田
弘之 増岡
克弥 星野
正泰 名越
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
JFE Steel Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to JP2008319131A priority Critical patent/JP5354165B2/en
Application filed by JFE Steel Corp filed Critical JFE Steel Corp
Priority to US13/129,504 priority patent/US20110226387A1/en
Priority to CN2009801454920A priority patent/CN102216493A/en
Priority to PCT/JP2009/058426 priority patent/WO2010070942A1/en
Priority to EP09833249.7A priority patent/EP2366812B1/en
Priority to CA2742354A priority patent/CA2742354C/en
Priority to KR1020117010906A priority patent/KR20110073573A/en
Priority to TW098113978A priority patent/TWI516638B/en
Publication of JP2009203547A publication Critical patent/JP2009203547A/en
Application granted granted Critical
Publication of JP5354165B2 publication Critical patent/JP5354165B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C2/00Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
    • C23C2/26After-treatment
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C22/00Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
    • C23C22/05Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
    • C23C22/06Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
    • C23C22/48Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 not containing phosphates, hexavalent chromium compounds, fluorides or complex fluorides, molybdates, tungstates, vanadates or oxalates
    • C23C22/53Treatment of zinc or alloys based thereon
    • CCHEMISTRY; METALLURGY
    • C23COATING 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
    • C23CCOATING 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
    • C23C8/00Solid 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
    • C23C8/02Pretreatment of the material to be coated

Description

本発明は、プレス成形時の摺動抵抗が小さく優れたプレス成形性を有する亜鉛系めっき鋼板を安定して製造する方法および優れたプレス成形性を有する亜鉛系めっき鋼板に関するものである。   The present invention relates to a method for stably producing a zinc-based plated steel sheet having a small sliding resistance during press forming and having excellent press formability, and a zinc-based plated steel sheet having excellent press formability.

亜鉛系めっき鋼板は、自動車車体用途を中心に広範な分野で広く利用されている。そのような用途での亜鉛系めっき鋼板は、プレス成形を施されて使用に供される。しかし、亜鉛系めっき鋼板は、冷延鋼板に比べてプレス成形性が劣るという欠点を有する。これはプレス金型での亜鉛系めっき鋼板の摺動抵抗が冷延鋼板に比べて大きいことが原因である。すなわち、金型とビードでの摺動抵抗が大きい部分で亜鉛系めっき鋼板がプレス金型に流入しにくくなり、鋼板の破断が起こりやすい。   Zinc-based galvanized steel sheets are widely used in a wide range of fields centering on automobile body applications. Zinc-based plated steel sheets for such applications are subjected to press forming and used. However, the zinc-based plated steel sheet has a drawback that the press formability is inferior to that of the cold-rolled steel sheet. This is because the sliding resistance of the galvanized steel sheet in the press die is larger than that of the cold-rolled steel sheet. That is, the galvanized steel sheet is less likely to flow into the press mold at a portion where the sliding resistance between the mold and the bead is large, and the steel sheet tends to break.

ここで、亜鉛系めっき鋼板の中でも特に、溶融亜鉛めっき処理後合金化処理を施す合金化溶融亜鉛めっき鋼板は合金化処理を施さない溶融亜鉛めっき鋼板と比較して溶接性および塗装性に優れることから、自動車車体用途としてはより好適に用いられている。   Here, among galvanized steel sheets, alloyed hot dip galvanized steel sheets that are subjected to alloying after hot dip galvanizing are superior in weldability and paintability compared to hot dip galvanized steel sheets that are not subjected to alloying. Therefore, it is more suitably used for automobile body applications.

合金化溶融亜鉛めっき鋼板は、鋼板に亜鉛めっきを施した後、加熱処理を行い、鋼板中のFeとめっき層中のZnが拡散し合金化反応が生じることにより、Fe−Zn合金相を形成させたものである。このFe−Zn合金相は、通常、Γ相、δ相、ζ相からなる皮膜であり、Fe濃度が低くなるに従い、すなわち、Γ相→δ1相→ζ相の順で、硬度ならびに融点が低下する傾向がある。このため、摺動性の観点からは、高硬度で、融点が高く凝着の起こりにくい高Fe濃度の皮膜が有効であり、プレス成形性を重視する合金化溶融亜鉛めっき鋼板は、皮膜中の平均Fe濃度を高めに製造されている。 An alloyed hot-dip galvanized steel sheet is formed by galvanizing the steel sheet and then heat-treating to form an Fe-Zn alloy phase by diffusion of Fe in the steel sheet and Zn in the plating layer to cause an alloying reaction. It has been made. This Fe-Zn alloy phase is usually a film composed of a Γ phase, a δ 1 phase, and a ζ phase. As the Fe concentration decreases, that is, in the order of Γ phase → δ 1 phase → ζ phase, hardness and melting point Tends to decrease. For this reason, from the viewpoint of slidability, a coating with high hardness, high melting point and high Fe concentration is effective, and alloyed hot-dip galvanized steel sheet, which emphasizes press formability, Manufactured with high average Fe concentration.

しかしながら、高Fe濃度の皮膜では、めっき−鋼板界面に硬くて脆いΓ相が形成されやすく、加工時に界面から剥離する現象、いわゆるパウダリングが生じやすい問題を有している。   However, a coating film having a high Fe concentration has a problem that a hard and brittle Γ phase is easily formed at the plating-steel plate interface, and a phenomenon of peeling from the interface during processing, that is, so-called powdering is likely to occur.

上記の問題を解決する方法として、特許文献1および特許文献2には、亜鉛系めっき鋼板の表面に電解処理、浸漬処理、塗布酸化処理、または加熱処理を施すことにより、ZnOを主体とする酸化膜を形成させて溶接性、加工性を向上させる技術が開示されている。   As a method for solving the above problem, Patent Document 1 and Patent Document 2 disclose that oxidation of ZnO is mainly performed by subjecting the surface of a zinc-based plated steel sheet to electrolytic treatment, immersion treatment, coating oxidation treatment, or heat treatment. A technique for improving weldability and workability by forming a film is disclosed.

しかしながら、特許文献1および2の技術を合金化溶融亜鉛めっき鋼板に適用した場合、合金化溶融めっき鋼板はAl酸化物が存在することにより、表面の反応性が劣る、そして表面の凹凸が大きいためにプレス成形性の改善効果を安定して得ることはできない。即ち、表面の反応性が低いため、電解処理、浸漬処理、塗布酸化処理及び加熱処理等を行っても、所定の皮膜を表面に形成することは困難であり、反応性の低い部分、すなわち、Al酸化物量が多い部分では膜厚が薄くなってしまう。また、表面の凹凸が大きいため、プレス成型時にプレス金型と直接接触するのは表面の凸部となるが、凸部のうち膜厚の薄い部分と金型との接触部での摺動抵抗が大きくなり、プレス成形性の改善効果が十分には得られない。
そこで、特許文献3では、鋼板を溶融亜鉛めっき後、加熱処理により合金化し、さらに調質圧延を施した後に、pH緩衝作用を有する酸性溶液と接触させ、1〜30秒保持し、水洗することで、めっき表層に酸化物層を形成させる技術を開示している。
同じく合金化処理を施さない溶融亜鉛めっき鋼板の表面平坦部に均一に酸化物層を形成させる手法として、特許文献4では、調質圧延後の溶融亜鉛めっき鋼板をpH緩衝作用を有する酸性溶液と接触させ、その後、鋼板表面に酸性溶液の液膜が形成された状態で所定時間保持した後水洗、乾燥する方法が開示している。
特開昭53-60332号公報 特開平2−190483号公報 特開2003−306781号公報 特開2004−3004号公報
However, when the techniques of Patent Documents 1 and 2 are applied to an alloyed hot dip galvanized steel sheet, the surface of the alloyed hot dip galvanized steel sheet is inferior due to the presence of Al oxide, and the surface irregularities are large. In addition, the effect of improving the press formability cannot be obtained stably. That is, since the surface reactivity is low, it is difficult to form a predetermined film on the surface even when electrolytic treatment, immersion treatment, coating oxidation treatment, heat treatment, and the like are performed. The film thickness is reduced in the portion where the amount of Al oxide is large. In addition, since the surface irregularities are large, it is the surface protrusions that come into direct contact with the press die during press molding, but the sliding resistance at the contact portion between the thin part of the protrusions and the mold As a result, the effect of improving press formability cannot be sufficiently obtained.
So, in patent document 3, after hot-dip galvanizing and alloying by heat processing, and also performing temper rolling, it is made to contact with the acidic solution which has pH buffer action, hold | maintain for 1 to 30 seconds, and wash with water. Thus, a technique for forming an oxide layer on the plating surface layer is disclosed.
Similarly, as a method for uniformly forming an oxide layer on a surface flat portion of a hot dip galvanized steel sheet that is not subjected to alloying treatment, Patent Document 4 discloses that an galvanized steel sheet after temper rolling is treated with an acidic solution having a pH buffering action. The method of making it contact, and then washing | cleaning and drying after hold | maintaining for a predetermined time in the state in which the liquid film of the acidic solution was formed in the steel plate surface is disclosed.
JP-A-53-60332 Japanese Patent Laid-Open No. 2-190483 Japanese Patent Laid-Open No. 2003-306781 Japanese Patent Laid-Open No. 2004-3004

上記特許文献3および4に開示されている技術を適用した場合、従来の製造条件においては良好なプレス成形性を得ることができる。しかし、近年では、生産性向上のためにより短時間でより厚い酸化膜を生成させる製造方法の開発が望まれており、このような条件で行った場合、特許文献3、4に開示される技術では十分な酸化膜が形成されず、良好なプレス成形性が得られないことがある。   When the techniques disclosed in Patent Documents 3 and 4 are applied, good press formability can be obtained under conventional manufacturing conditions. However, in recent years, it has been desired to develop a manufacturing method for generating a thicker oxide film in a shorter time in order to improve productivity, and the techniques disclosed in Patent Documents 3 and 4 are performed under such conditions. In such a case, a sufficient oxide film is not formed, and good press formability may not be obtained.

本発明は、かかる事情に鑑み、優れたプレス成形性を有する亜鉛系めっき鋼板を短時間でも安定的に製造することが可能な製造方法および優れたプレス成形性を有する亜鉛系めっき鋼板を提供することを目的とする。   In view of such circumstances, the present invention provides a production method capable of stably producing a galvanized steel sheet having excellent press formability even in a short time and a galvanized steel sheet having excellent press formability. For the purpose.

本発明者らは、上記の課題を解決すべく、鋭意研究を重ねた。その結果、以下の知見を得た。   The inventors of the present invention have made extensive studies to solve the above problems. As a result, the following knowledge was obtained.

特許文献3および4の技術に使われる酸性溶液は、亜鉛の溶解を促進する目的でpH緩衝作用を有している。そのため、pHの上昇が遅らされ、酸化物層の形成が遅れていることが考えられる。そして、酸化物層を形成する亜鉛をめっき皮膜から溶出した亜鉛で補うために、酸化膜の生成時間に亜鉛の溶出時間が含まれる。その結果、短時間で厚い酸化膜を生成させることが困難になっていると考えられる。   The acidic solution used in the techniques of Patent Documents 3 and 4 has a pH buffering action for the purpose of promoting the dissolution of zinc. Therefore, it is considered that the increase in pH is delayed and the formation of the oxide layer is delayed. And in order to make up for the zinc which forms an oxide layer with the zinc eluted from the plating film, the elution time of zinc is included in the generation time of the oxide film. As a result, it is considered difficult to form a thick oxide film in a short time.

そこで、本発明者らは酸化膜を生成させる水溶液中に亜鉛イオンを予め含有させることによって亜鉛の溶出時間を省略してより短時間で酸化膜を生成させる技術を考案した。しかしながら、単に水溶液中に亜鉛イオンを予め含有させるだけでは酸化膜の形成は促進されなかった。特に、特許文献3および4の実施例に示されるpH2では処理液中に亜鉛を含有させても酸化膜の形成は促進されなかった。   Accordingly, the present inventors have devised a technique for generating an oxide film in a shorter time by omitting the zinc elution time by previously containing zinc ions in an aqueous solution for generating an oxide film. However, the formation of the oxide film was not promoted simply by previously containing zinc ions in the aqueous solution. In particular, at pH 2 shown in Examples of Patent Documents 3 and 4, formation of an oxide film was not promoted even when zinc was contained in the treatment liquid.

この理由は、特許文献3および4の技術では、亜鉛が溶出する際に同時に起こる水素イオンの還元で表面近傍のpHが上昇して亜鉛酸化物が生成しやすい環境になっているのに対して、単に水溶液中に亜鉛イオンを含有させただけでは表面近傍のpHの上昇が起こらず亜鉛酸化物が生成しやすい環境が形成されないためであると考えられる。   The reason for this is that, in the techniques of Patent Documents 3 and 4, the reduction of hydrogen ions that occurs simultaneously with the elution of zinc increases the pH in the vicinity of the surface and makes it easy to generate zinc oxide. It is considered that simply adding zinc ions in the aqueous solution does not increase the pH in the vicinity of the surface and does not form an environment in which zinc oxide is easily generated.

そこで、本発明者等は、水溶液のpHを亜鉛酸化物が生成しやすいpH4〜6とする技術を考案した。そして、処理液のpHを4〜6とすることで、めっき皮膜の亜鉛がわずかに溶出して起こる表面pHの微小な上昇により亜鉛が水酸化物として生成することを見出した。   Therefore, the present inventors have devised a technique for adjusting the pH of the aqueous solution to pH 4 to 6 at which zinc oxide is easily generated. And it discovered that zinc was produced | generated as a hydroxide by the slight raise of the surface pH which occurs when the pH of a process liquid shall be 4-6 and zinc of a plating film elutes slightly.

本発明は、以上の知見に基づきなされたものであり、その要旨は以下の通りである。
[1]鋼板に亜鉛系めっきを施した後、鋼板を水溶液に接触処理し、接触処理終了後1〜60秒間保持した後、水洗・乾燥を行うことにより、鋼板表面に酸化物層を形成する亜鉛系めっき鋼板の製造方法において、
鋼板を接触処理する前記水溶液は、亜鉛イオン濃度として5〜100g/lの範囲で亜鉛イオンを含有し、pHが4〜6であり、液温が20〜70℃であることを特徴とする亜鉛系めっき鋼板の製造方法。
[2]前記[1]において、前記水溶液中には、亜鉛の硫酸塩を含むことを特徴とする亜鉛系めっき鋼板の製造方法。
[3]前記[1]または[2]において、前記水溶液に接触後に鋼板表面に形成する液膜が5〜30g/m2であることを特徴とする亜鉛系めっき鋼板の製造方法。
[4]前記[1]〜[3]のいずれかに記載の亜鉛系めっき鋼板の製造方法により製造され、金属成分としては亜鉛を主体として含む酸化物層を鋼板表面に平均厚さ10nm以上形成したことを特徴とする亜鉛系めっき鋼板。
The present invention has been made based on the above findings, and the gist thereof is as follows.
[1] After the zinc plating is applied to the steel sheet, the steel sheet is contact-treated with an aqueous solution, held for 1 to 60 seconds after completion of the contact treatment, and then washed with water and dried to form an oxide layer on the steel sheet surface. In the method for producing a zinc-based plated steel sheet,
The aqueous solution for contact-treating a steel sheet contains zinc ions in a zinc ion concentration range of 5 to 100 g / l, has a pH of 4 to 6, and a liquid temperature of 20 to 70 ° C. Manufacturing method of a galvanized steel sheet.
[2] The method for producing a galvanized steel sheet according to [1], wherein the aqueous solution contains zinc sulfate.
[3] The method for producing a zinc-based plated steel sheet according to [1] or [2], wherein a liquid film formed on the steel sheet surface after contact with the aqueous solution is 5 to 30 g / m 2 .
[4] Manufactured by the method for producing a galvanized steel sheet according to any one of [1] to [3] above, an oxide layer mainly containing zinc as a metal component is formed on the steel sheet surface with an average thickness of 10 nm or more A galvanized steel sheet characterized by that.

なお、本発明において、亜鉛系めっき鋼板とは、亜鉛を主成分とする皮膜を表面に形成させためっき鋼板であり、溶融亜鉛めっき鋼板(略してGI鋼板と称す)、合金化溶融亜鉛めっき鋼板(略してGA鋼板と称す)、電気亜鉛めっき鋼板(略してEG鋼板と称す)、蒸着亜鉛めっき鋼板やFe、Al、Ni、MgCo等の合金元素を含有する合金亜鉛めっき鋼板等が含まれる。   In the present invention, the galvanized steel sheet is a galvanized steel sheet on which a coating containing zinc as a main component is formed, a hot dip galvanized steel sheet (referred to as GI steel sheet for short), an alloyed hot dip galvanized steel sheet. (Abbreviated as GA steel plate), electrogalvanized steel plate (abbreviated as EG steel plate), vapor-deposited galvanized steel plate, alloy galvanized steel plate containing alloy elements such as Fe, Al, Ni, MgCo and the like.

本発明によれば、短時間の製造条件においても、省スペースで、プレス成形時の摺動抵抗が小さく優れたプレス成形性を有する亜鉛系めっき鋼板を安定して製造できる。そして、例えば、成形荷重が高く型かじりを生じやすい高強度亜鉛系めっき鋼板を製造するに際しても、プレス成形時の摺動抵抗が小さく、優れたプレス成形性を有することができる。   ADVANTAGE OF THE INVENTION According to this invention, the zinc-plated steel plate which has the excellent press-formability with small sliding resistance at the time of press molding, and excellent press-formability can be manufactured stably also in short-time manufacturing conditions. For example, when producing a high-strength galvanized steel sheet that has a high forming load and is likely to cause mold galling, the sliding resistance during press forming is small, and excellent press formability can be achieved.

本発明は、鋼板に亜鉛系めっきを施した後、鋼板を水溶液に接触処理し、接触処理終了後1〜60秒間保持した後、水洗・乾燥を行うことにより、亜鉛系めっき鋼板表面に酸化物層を形成するに際し、前記水溶液として、亜鉛イオン濃度として5〜100g/lの範囲で亜鉛イオンを含有し、pHが4〜6であり、液温が20〜70℃とする。このように、鋼板を接触処理する水溶液として、所定の濃度の亜鉛イオンを含み、pHと液温を規定した水溶液とすることは、本発明において、重要な要件であり、特徴である。これにより、良好なプレス成形性を確保するために十分な酸化物層を短時間で形成させることができる。
なお、接触処理終了後とは、浸漬処理の場合は浸漬工程を終了した後を、スプレー処理の場合はスプレー工程が終了した後を、ロール塗布の場合は塗布工程が終了した後を示すものである。
In the present invention, after zinc plating is applied to the steel sheet, the steel sheet is contact-treated with an aqueous solution, and after the contact treatment is completed, the oxide is formed on the surface of the zinc-based plated steel sheet by washing and drying after holding for 1 to 60 seconds. In forming the layer, the aqueous solution contains zinc ions in the range of 5 to 100 g / l as the zinc ion concentration, the pH is 4 to 6, and the liquid temperature is 20 to 70 ° C. As described above, it is an important requirement and feature in the present invention that an aqueous solution containing a predetermined concentration of zinc ions and having a defined pH and liquid temperature is used as an aqueous solution for contact-treating a steel sheet. Thereby, a sufficient oxide layer can be formed in a short time to ensure good press moldability.
The term “after contact treatment” means that after the immersion process is completed in the case of immersion treatment, after the spray process is completed in the case of spray treatment, and after the application step is completed in the case of roll coating. is there.

鋼板を接触処理する水溶液として、亜鉛イオンを含有する水溶液を使用することにより、亜鉛の溶出時間を省略することが可能となる。この時、亜鉛イオンは亜鉛イオン濃度として、5〜100g/lの範囲とする。亜鉛イオン濃度が5g/l未満であると、十分な亜鉛が供給されずに酸化物層の形成がおこらなくなる。一方、100g/lを超えると形成される酸化物層に含まれる硫酸濃度が高くなり、その後に行われる化成処理工程で酸化物が溶解したときに処理液を汚染することが懸念される。   By using an aqueous solution containing zinc ions as the aqueous solution for contact-treating the steel sheet, it is possible to omit the elution time of zinc. At this time, zinc ion is made into the range of 5-100 g / l as a zinc ion density | concentration. When the zinc ion concentration is less than 5 g / l, sufficient zinc is not supplied and the oxide layer is not formed. On the other hand, when the concentration exceeds 100 g / l, the concentration of sulfuric acid contained in the formed oxide layer becomes high, and there is a concern that the treatment liquid is contaminated when the oxide is dissolved in the chemical conversion treatment step performed thereafter.

安定な亜鉛化合物を酸化物層として形成させるためには、亜鉛イオンを硫酸塩として添加するのが好ましい。硫酸塩として添加した場合、形成される酸化物層に硫酸イオンが取り込まれ、酸化物層を安定させる効果があると思われる。   In order to form a stable zinc compound as an oxide layer, it is preferable to add zinc ions as sulfates. When added as a sulfate, sulfate ions are taken into the oxide layer to be formed, which seems to have an effect of stabilizing the oxide layer.

また、前述した通り、単に処理液中に亜鉛イオンを予め含有させるだけでは酸化膜の形成は促進されない。そこで、本発明では、pHを亜鉛酸化物が生成しやすいpH4〜6とする必要がある。処理液のpHを4〜6とすれば、めっき皮膜の亜鉛がわずかに溶出して起こる表面pHの微小な上昇により亜鉛が水酸化物として生成する。これらの結果として、亜鉛溶出時間を省略し、かつ、亜鉛酸化物の生成が可能となる。pHが6を超える場合には水溶液中で亜鉛イオンは沈殿(水酸化物の形成)し、鋼板表面に酸化物として形成されなくなる。また、 pHが4未満の場合は、上に記したように、pH上昇の遅延による酸化物層の形成の阻害となる。   Further, as described above, the formation of the oxide film is not promoted simply by previously containing zinc ions in the treatment liquid. Therefore, in the present invention, it is necessary to adjust the pH to pH 4 to 6 where zinc oxide is easily generated. If the pH of the treatment liquid is 4 to 6, zinc is generated as a hydroxide by a slight increase in surface pH caused by slight elution of zinc in the plating film. As a result of these, zinc elution time can be omitted and zinc oxide can be produced. When the pH exceeds 6, zinc ions precipitate (form hydroxide) in the aqueous solution and are no longer formed as oxides on the steel sheet surface. On the other hand, when the pH is less than 4, as described above, the formation of the oxide layer is hindered due to the delay of the pH increase.

水溶液の温度については、20〜70℃とする。酸化物層の形成反応は、水溶液への接触後、所定時間保持する際に生じるため、保持時の板温を20〜70℃の範囲に制御することは有効である。20℃未満であると、酸化物層の生成反応に長時間を有し、生産性の低下を招く。一方、70℃を超える場合には、反応は比較的すばやく進行するが、逆に鋼板表面に処理ムラを発生しやすくなる。   About the temperature of aqueous solution, it shall be 20-70 degreeC. Since the formation reaction of the oxide layer occurs when it is held for a predetermined time after contact with the aqueous solution, it is effective to control the plate temperature at the time of holding in the range of 20 to 70 ° C. If it is lower than 20 ° C., the reaction for forming the oxide layer takes a long time, resulting in a decrease in productivity. On the other hand, when the temperature exceeds 70 ° C., the reaction proceeds relatively quickly, but on the contrary, processing unevenness is likely to occur on the steel sheet surface.

特許文献3および4で用いられる水溶液は酸性であることと、pH緩衝作用を有することを特徴としている。しかし、本発明は亜鉛イオンを含む水溶液を使用するため、水溶液のpHが高くして亜鉛の溶解を十分に起こさなくても、十分な酸化物層を形成させることができる。また、pHの上昇が速やかに起こった方が酸化物の形成には有利であると思われる。ゆえに、pH緩衝作用は必ずしも必須ではない。   The aqueous solutions used in Patent Documents 3 and 4 are characterized by being acidic and having a pH buffering action. However, since the present invention uses an aqueous solution containing zinc ions, a sufficient oxide layer can be formed even if the pH of the aqueous solution is high and zinc does not sufficiently dissolve. Moreover, it seems that it is advantageous for the formation of the oxide that the pH rises rapidly. Therefore, pH buffering is not always essential.

本発明では、鋼板表面に接触する水溶液中には亜鉛を含有していれば、摺動性に優れた酸化物層を安定して形成できるため、水溶液中にその他の金属イオンや無機化合物などを不純物として、あるいは故意に含有していても本発明の効果が損なわれるものではない。そして、N、P、B、Cl、Na、Mn、Ca、Mg、Ba、Sr、Siなどが酸化物層中に取り込まれても、本発明の効果が損なわれない限り適用可能である。   In the present invention, if zinc is contained in the aqueous solution in contact with the steel sheet surface, an oxide layer excellent in slidability can be stably formed. Therefore, other metal ions, inorganic compounds, and the like are added to the aqueous solution. Even if it contains as an impurity or deliberately, the effect of this invention is not impaired. Even if N, P, B, Cl, Na, Mn, Ca, Mg, Ba, Sr, Si, or the like is incorporated into the oxide layer, it is applicable as long as the effect of the present invention is not impaired.

亜鉛系めっき鋼板を以上からなる水溶液に接触させた後に、その水溶液が薄い液膜状で鋼板表面に存在することが望ましい。これは、鋼板表面に存在する水溶液の量が多いと、亜鉛の溶解が生じても水溶液のpHが上昇しにくく、酸化物層を形成するまでに長時間を有するためである。この観点から、鋼板表面に形成する水溶液膜の量は、30g/m以下に調整することが好ましく有効である。また、液膜の乾燥を防ぐ目的で5g/m2以上の液膜量が適している。以上より、好ましくは、前記水溶液に接触後に鋼板表面に形成する液膜は5〜30g/m2とする。なお、水溶液膜量の調整は、絞りロール、エアワイピング等で行うことができる。 After the galvanized steel sheet is brought into contact with the aqueous solution comprising the above, it is desirable that the aqueous solution exists in the form of a thin liquid film on the steel sheet surface. This is because if the amount of the aqueous solution existing on the surface of the steel sheet is large, the pH of the aqueous solution is unlikely to rise even if zinc is dissolved, and it takes a long time to form the oxide layer. From this viewpoint, it is preferable and effective to adjust the amount of the aqueous film formed on the steel sheet surface to 30 g / m 2 or less. A liquid film amount of 5 g / m 2 or more is suitable for the purpose of preventing the liquid film from drying. As mentioned above, Preferably, the liquid film formed on the steel plate surface after contact with the aqueous solution is 5 to 30 g / m 2 . The amount of the aqueous film can be adjusted by a squeeze roll, air wiping or the like.

また、水溶液に浸漬後、水洗までの時間(水洗までの保持時間)は、1〜60秒間とする。水洗までの時間が1秒未満であると、十分な酸化物層が形成される前に、水溶液が洗い流されるため、摺動性の向上効果が得られない。一方、60秒を超えた場合の保持時間では生産性を落としてしまう。短時間でも安定的に製造することを本発明の目的とするため、本発明の効果を十分に発揮する点から保持時間は60秒以下とする。   Moreover, after being immersed in aqueous solution, the time to water washing (holding time to water washing) shall be 1 to 60 seconds. If the time until washing with water is less than 1 second, the aqueous solution is washed out before the sufficient oxide layer is formed, so that the effect of improving the slidability cannot be obtained. On the other hand, productivity is reduced in the holding time when it exceeds 60 seconds. Since it is an object of the present invention to manufacture stably even in a short time, the holding time is set to 60 seconds or less from the viewpoint of sufficiently exerting the effects of the present invention.

以上より、本発明のめっき鋼板の表面には、金属成分として亜鉛を主体として含み、平均厚さが10nm以上の酸化物層が得られることになる。
なお、亜鉛を主体とするとは、金属成分としては亜鉛を50質量%以上含むことである。
As described above, an oxide layer containing zinc as a main component and having an average thickness of 10 nm or more is obtained on the surface of the plated steel sheet of the present invention.
The phrase “mainly composed of zinc” means that the metal component contains 50% by mass or more of zinc.

なお、本発明における酸化物層とは、金属成分として亜鉛を主体として含んだ酸化物及び/又は水酸化物などからなる層のことである。この酸化物層の平均厚さが10nm以上であることが必要である。酸化物層の平均厚さが10nm未満に薄くなると摺動抵抗を低下させる効果が不十分となる。一方、亜鉛を必須成分として含む酸化物層の平均厚さが100nmを越えると、プレス加工中に皮膜が破壊し摺動抵抗が上昇し、また溶接性が低下する傾向にあるため好ましくない。   The oxide layer in the present invention is a layer made of an oxide and / or hydroxide mainly containing zinc as a metal component. The average thickness of the oxide layer needs to be 10 nm or more. When the average thickness of the oxide layer is reduced to less than 10 nm, the effect of reducing the sliding resistance becomes insufficient. On the other hand, if the average thickness of the oxide layer containing zinc as an essential component exceeds 100 nm, the coating is broken during press working, the sliding resistance is increased, and the weldability tends to be lowered.

なお、亜鉛系めっき鋼板を亜鉛を含む水溶液に接触処理させる方法には特に制限はなく、めっき鋼板を水溶液に浸漬する方法、めっき鋼板に水溶液をスプレーする方法、塗布ロールを介して水溶液をめっき鋼板に塗布する方法等があり、最終的に薄い液膜状で鋼板表面に存在することが望ましい。   In addition, there is no restriction | limiting in particular in the method of making a zinc-based plated steel plate contact process with the aqueous solution containing zinc, the method of immersing a plated steel plate in aqueous solution, the method of spraying aqueous solution on a plated steel plate, and plating aqueous solution through a coating roll It is desirable that the film is finally formed in a thin liquid film form on the surface of the steel sheet.

また本発明に係る合金化溶融亜鉛めっき鋼板を製造するに関しては、めっき浴中にAlが添加されていることが必要であるが、Al以外の添加元素成分は特に限定されない。すなわち、Alの他にPb、Sb、Si、Sn、Mg、Mn、Ni、Ti、Li、Cuなどが含有または添加されていても、本発明の効果が損なわれない限り適用可能である。   In addition, for producing the galvannealed steel sheet according to the present invention, it is necessary that Al be added to the plating bath, but the additive element components other than Al are not particularly limited. That is, even if Pb, Sb, Si, Sn, Mg, Mn, Ni, Ti, Li, Cu, etc. are contained or added in addition to Al, they are applicable as long as the effect of the present invention is not impaired.

次に、本発明を実施例により更に詳細に説明する。
板厚0.8mmの冷延鋼板上に、片面当たりの付着量が45g/m、Al濃度が0.20質量%の溶融亜鉛めっきを施した後に、調質圧延を行ったGI鋼板を作製した。また、板厚0.8mmの冷延鋼板上に、常法の合金化溶融亜鉛めっき法により、片面当たりのめっき付着量が45g/m、Fe濃度が10質量%、Al濃度が0.20質量%のめっき皮膜を形成し、更に調質圧延を行ったGA鋼板を作製した。また、板厚0.8mmの冷延鋼板上に、常法の電気亜鉛めっき法により、片面当たりのめっき付着量が30g/m2のめっき皮膜を有するEG鋼板を作成した。
引き続き、図1に示す構成の処理設備を用いて酸化物層を形成した。まず、上記により得られたGI鋼板、GA鋼板およびEG鋼板を、溶液槽2で、表1に示す処理液組成、温度およびpHが異なる水溶液に浸漬した。次いで、絞りロール3で鋼板表面の液膜量を調整した。液膜量の調整は、絞りロールの圧力を変化させることで行った。次いで、洗浄槽5、洗浄槽6を空通しし、洗浄槽7で50℃の温水を鋼板にスプレーして洗浄し、ドライヤ8で乾燥し、めっき表面に酸化物層を形成した。
Next, the present invention will be described in more detail with reference to examples.
On a cold-rolled steel sheet having a thickness of 0.8 mm, a GI steel sheet that was subjected to temper rolling after hot dip galvanizing with an adhesion amount per side of 45 g / m 2 and an Al concentration of 0.20% by mass was produced. . Further, on a cold-rolled steel sheet having a thickness of 0.8 mm, the amount of plating adhesion per side is 45 g / m 2 , the Fe concentration is 10% by mass, and the Al concentration is 0.20% by a conventional alloying hot dip galvanizing method. % Plating film was formed, and a GA steel sheet was further subjected to temper rolling. Further, an EG steel sheet having a plating film with a coating amount of 30 g / m 2 per one side was prepared on a cold-rolled steel sheet having a thickness of 0.8 mm by a conventional electrogalvanizing method.
Subsequently, an oxide layer was formed using a processing facility having the configuration shown in FIG. First, the GI steel sheet, GA steel sheet, and EG steel sheet obtained as described above were immersed in aqueous solutions having different treatment liquid compositions, temperatures, and pH values shown in Table 1 in the solution tank 2. Next, the amount of liquid film on the steel sheet surface was adjusted with the drawing roll 3. The liquid film amount was adjusted by changing the pressure of the squeeze roll. Next, the cleaning tank 5 and the cleaning tank 6 were evacuated, and the cleaning tank 7 was sprayed with 50 ° C. hot water to be washed, dried with a dryer 8, and an oxide layer was formed on the plating surface.

溶液槽2で浸漬処理を行う水溶液は、 亜鉛イオンを添加する目的で硫酸亜鉛七水和物を所定量添加した水溶液を使用した。 なお、一部、比較のために酢酸ナトリウム20g/Lを含んだ溶液を硫酸でpHを調整した溶液も用いた。   The aqueous solution to be dipped in the solution tank 2 was an aqueous solution to which a predetermined amount of zinc sulfate heptahydrate was added for the purpose of adding zinc ions. For comparison, a solution containing 20 g / L of sodium acetate with a pH adjusted with sulfuric acid was also used for comparison.

水洗までの保持時間は、絞りロール3で液膜量の調整を行い、洗浄槽7で洗浄開始するまでの時間であり、ラインスピードを変化させることで調整するとともに、一部、絞りロール3出側のシャワー水洗装置4を用いて絞り直後に鋼板を洗浄するものも作製した。   The holding time until water washing is the time until the liquid film amount is adjusted with the squeezing roll 3 and the cleaning is started in the cleaning tank 7, and is adjusted by changing the line speed. What washed the steel plate immediately after squeezing using the shower water washing apparatus 4 of the side was also produced.

次に、以上のように作製した鋼板について、自動車用外板として十分な外観を有するか判定するとともに、プレス成形性を簡易的に評価する手法として摩擦係数の測定、および実際の成形性をより詳細にシミュレートする目的で球頭張出試験を実施した。なお、測定方法は以下の通りである。   Next, regarding the steel sheet produced as described above, it is determined whether it has a sufficient appearance as an automobile outer plate, and as a method for simply evaluating the press formability, the measurement of the friction coefficient and the actual formability are further improved. A ball head overhang test was conducted for the purpose of simulating in detail. The measuring method is as follows.

(1)プレス成形性評価試験(摩擦係数測定試験)
プレス成形性を評価するために、各供試材の摩擦係数を以下のようにして測定した。
図2は摩擦係数測定装置を示す概略正面図である。同図に示すように、供試材から採取した摩擦係数測定用試料11が試料台12に固定され、試料台12は、水平移動可能なスライドテーブル13の上面に固定されている。スライドテーブル13の下面には、これに接したローラ14を有する上下動可能なスライドテーブル支持台15が設けられ、これを押し上げることによりビード16による摩擦係数測定用試料11への押し付け荷重Nを測定するための第1ロードセル17がスライドテーブル支持台15に取り付けられている。上記押し付け力を作用させた状態でスライドテーブル13を水平方向へ移動させるための摺動抵抗力Fを測定するために第2ロードセル18が、スライドテーブル13の一方の端部に取り付けられている。なお、潤滑油としてスギムラ化学社製のプレス用洗浄油プレトンR352Lを摩擦係数測定用試料11の表面に塗布して試験を行った。
(1) Press formability evaluation test (Friction coefficient measurement test)
In order to evaluate the press formability, the friction coefficient of each test material was measured as follows.
FIG. 2 is a schematic front view showing the friction coefficient measuring apparatus. As shown in the figure, a friction coefficient measurement sample 11 collected from a test material is fixed to a sample table 12, and the sample table 12 is fixed to the upper surface of a slide table 13 that can move horizontally. On the lower surface of the slide table 13, there is provided a slide table support base 15 having a roller 14 in contact with the slide table 13 and capable of moving up and down. By pushing up the slide table support base 15, a pressing load N applied to the friction coefficient measurement sample 11 by the bead 16 is measured. A first load cell 17 is attached to the slide table support base 15. A second load cell 18 is attached to one end of the slide table 13 in order to measure the sliding resistance force F for moving the slide table 13 in the horizontal direction with the pressing force applied. In addition, the cleaning oil Preton R352L for press manufactured by Sugimura Chemical Co., Ltd. was applied to the surface of the friction coefficient measurement sample 11 as a lubricant, and the test was performed.

図3、4は使用したビードの形状・寸法を示す概略斜視図である.ビード16の下面が試料11の表面に押し付けられた状態で摺動する。図3に示すビード16の形状は幅10mm、試料の摺動方向長さ12mm、摺動方向両端の下部は曲率4.5mmRの曲面で構成され、試料が押し付けられるビード下面は幅10mm、摺動方向長さ3mmの平面を有する。図4に示すビード16の形状は幅10mm、試料の摺動方向長さ69mm、摺動方向両端の下部は曲率4.5mmRの曲面で構成され、試料が押し付けられるビード下面は幅10mm、摺動方向長さ60mmの平面を有する。   Figures 3 and 4 are schematic perspective views showing the shape and dimensions of the beads used. The bottom surface of the bead 16 slides while being pressed against the surface of the sample 11. The bead 16 shown in FIG. 3 has a width of 10 mm, a length of 12 mm in the sliding direction of the sample, and a lower portion at both ends of the sliding direction is formed by a curved surface having a curvature of 4.5 mm. It has a plane with a direction length of 3 mm. The bead 16 shown in FIG. 4 has a width of 10 mm, a length of 69 mm in the sliding direction of the sample, and a lower portion at both ends of the sliding direction is formed by a curved surface having a curvature of 4.5 mm. It has a plane with a direction length of 60 mm.

摩擦係数測定試験は下に示す2条件で行った。
[条件1]
図3に示すビードを用い、押し付け荷重N:400kgf、試料の引き抜き速度(スライドテーブル13の水平移動速度):100cm/minとした。
[条件2]
図4に示すビードを用い、押し付け荷重N:400kgf、試料の引き抜き速度(スライドテーブル13の水平移動速度):20cm/minとした。
供試材とビードとの間の摩擦係数μは、式:μ=F/Nで算出した。
The friction coefficient measurement test was performed under the following two conditions.
[Condition 1]
The bead shown in FIG. 3 was used, the pressing load N was 400 kgf, and the sample drawing speed (horizontal moving speed of the slide table 13) was 100 cm / min.
[Condition 2]
The bead shown in FIG. 4 was used, the pressing load N was 400 kgf, and the sample drawing speed (horizontal moving speed of the slide table 13) was 20 cm / min.
The coefficient of friction μ between the specimen and the bead was calculated by the formula: μ = F / N.

(2)球頭張出試験
200×200mmサイズの供試材に対して、150mmφのポンチを使用して、液圧バルジ試験機により張出成形を行い、破断が生じた際の最大成形高さを測定した。この際、材料の流入を阻止する目的で100Tonのしわ押さえ力をかけ、ポンチが接触する面にのみ潤滑油を塗布した。使用した潤滑油は、前述した摩擦係数測定試験と同様のものである。
(3)酸化物層の厚さ(酸化膜厚)の測定
膜厚が96nmの熱酸化SiO2膜が形成されたSiウエハを参照物質として用い、蛍光X線分析装置でO・Kα X線を測定することで、SiO2換算の酸化層の平均厚さを求めた。分析面積は30mmφである。
(2) Ball head overhang test
A 200 × 200 mm size test material was stretched by a hydraulic bulge tester using a 150 mmφ punch, and the maximum molding height when a fracture occurred was measured. At this time, a wrinkle holding force of 100 Ton was applied for the purpose of preventing the inflow of the material, and the lubricating oil was applied only to the surface in contact with the punch. The used lubricating oil is the same as that in the friction coefficient measurement test described above.
(3) Measurement of oxide layer thickness (oxide film thickness) Using a Si wafer with a thermally oxidized SiO2 film with a film thickness of 96 nm as the reference material, measure O / Kα X-rays with a fluorescent X-ray analyzer. Thus, the average thickness of the oxide layer in terms of SiO 2 was obtained. The analysis area is 30 mmφ.

以上より得られた試験結果を表1および図5に示す。   The test results obtained above are shown in Table 1 and FIG.

表1に示す試験結果から下記事項が明らかとなった。
(1)No.1、47および60は溶液による処理を行っていないため、平坦部に摺動性を向上させるのに十分な酸化膜が形成されず、摩擦係数が高い。
(2)No.2〜4、No.48〜50およびNo.61〜63はpH緩衝作用を有する酸性溶液を用いた比較例である。30秒以上では摩擦係数が低く、最大形成高さも高くなっているものの、10秒の処理では十分な摩擦係数の低下および最大成形高さの向上を満たしていない。
(3) No.5〜7は、pH緩衝作用を有する酸性溶液を用いた比較例である。高い摩擦係数を示している。
(4)No.8〜10、No.51〜53およびNo.64〜66は、亜鉛イオンを含有しているが、その量が本発明の範囲よりも少ない比較例である。30秒以上では摩擦係数が低く、最大形成高さも高くなっているものの、10秒の処理では十分な摩擦係数の低下および最大成形高さの向上を満たしていない。
(5) No.11〜13、No.54〜56およびNo.67〜69は、は、亜鉛イオンを含有した溶液での処理を行った本発明例であり、摩擦係数が低下し、最大成形高さも増加している。また、No.14〜16およびNo.44〜46はNo.11〜13と同一の処理条件で液中の亜鉛イオン濃度を増加させた本発明例である。摩擦係数が低位安定化し、最大成形高さもさらに増加している。同様に、No.57〜59およびNo.70〜72はNo.54〜56と同一の処理条件で液中の亜鉛イオン濃度を増加させた本発明例である。摩擦係数が低位安定化し、最大成形高さもさらに増加している。
(6) No.17〜22は、鋼板表面に溶液膜を形成し、水洗を施すまでの時間を変化させた例である。保持なく水洗を行ったNo.17ではわずかに摩擦係数が低下するのみであるのに対して、1秒以上の保持時間となる No.18〜22は、摩擦係数は低下し、張出性も安定向上している。
(7)No.23〜40は、処理液温度を変化させた例であるが、処理液温度の低いNo.23〜25は、それ以外の例と比較して、摩擦係数および最大成形高さの向上効果が十分でない。一方、No.32〜34は、処理液温度の高い例であり、摩擦係数や最大成形高さの向上効果は十分であるが、処理ムラが多く見られ、自動車用外板として良好な外観を示していなかった。
(8)No.35〜40は、No.20〜22に対して、液膜形成量を変化させた本発明例である。水洗までの保持時間が同一のもので比較すると、液膜量が多い場合には、十分な摩擦係数の低下および最大成形高さの向上が得られているものの、液膜量が少ない場合に比べるとやや摩擦係数が高く最大成形高さも低くなっている。
(9)No.41〜43はpHが本発明の範囲よりも低い処理液を用いた比較例であるが、No.20〜22と比較して摩擦係数の低下の効果は認められず、最大成形高さの向上も見られない。
From the test results shown in Table 1, the following matters were clarified.
(1) No. Since 1, 47 and 60 are not treated with a solution, an oxide film sufficient to improve the slidability is not formed on the flat portion, and the coefficient of friction is high.
(2) No. 2-4, No. 48-50 and No. 61 to 63 are comparative examples using an acidic solution having a pH buffering action. Although the friction coefficient is low and the maximum formation height is high at 30 seconds or more, the treatment for 10 seconds does not satisfy a sufficient decrease in the friction coefficient and an improvement in the maximum molding height.
(3) No. 5 to 7 are comparative examples using an acidic solution having a pH buffering action. It shows a high coefficient of friction.
(4) No. 8-10, No. 51-53 and no. 64 to 66 are comparative examples which contain zinc ions but whose amount is less than the range of the present invention. Although the friction coefficient is low and the maximum formation height is high at 30 seconds or more, the treatment for 10 seconds does not satisfy a sufficient decrease in the friction coefficient and an improvement in the maximum molding height.
(5) No. 11-13, No. 54-56 and no. Nos. 67 to 69 are examples of the present invention in which the treatment with a solution containing zinc ions was performed, the friction coefficient was lowered, and the maximum molding height was also increased. No. 14-16 and no. 44 to 46 are No. It is the example of this invention which increased the zinc ion density | concentration in a liquid on the same process conditions as 11-13. The friction coefficient is stabilized at a low level, and the maximum molding height is further increased. Similarly, no. 57-59 and no. 70-72 is No. It is the example of this invention which increased the zinc ion density | concentration in a liquid on the process conditions same as 54-56. The friction coefficient is stabilized at a low level, and the maximum molding height is further increased.
(6) No. Examples 17 to 22 are examples in which the time until the solution film is formed on the steel plate surface and the water washing is changed is changed. No. washed with water without holding. In No. 17, the friction coefficient is only slightly lowered, but the holding time of 1 second or longer is obtained. In 18 to 22, the friction coefficient is lowered and the overhang property is stably improved.
(7) No. Nos. 23 to 40 are examples in which the treatment liquid temperature was changed. 23 to 25 are not sufficient in improving the friction coefficient and the maximum molding height as compared with the other examples. On the other hand, No. Nos. 32 to 34 are examples of high processing liquid temperatures, and although the effect of improving the friction coefficient and the maximum molding height is sufficient, many processing irregularities were seen and did not show a good appearance as an automobile outer plate .
(8) No. 35 to 40 are No. This is an example of the present invention in which the liquid film formation amount is changed with respect to 20-22. When compared with the same holding time until washing, when the amount of liquid film is large, a sufficient reduction in the coefficient of friction and improvement in the maximum molding height are obtained, but compared with the case where the amount of liquid film is small Slightly higher coefficient of friction and lower maximum molding height.
(9) No. 41-43 is a comparative example using a treatment liquid having a pH lower than the range of the present invention, but the effect of lowering the friction coefficient is not observed compared with No. 20-22, and the maximum molding height is improved. Also not seen.

図5は、酸化膜厚への亜鉛イオン濃度の影響を示す図である。図5によれば、亜鉛の濃度が5g/l以上であれば保持時間が短い場合(例えば、10秒)でも酸化膜厚が十分に厚く形成され、保持時間が短い場合に酸化膜厚が薄くなるという本発明の課題が解決されていることがわかる。   FIG. 5 is a diagram showing the influence of the zinc ion concentration on the oxide film thickness. According to FIG. 5, when the zinc concentration is 5 g / l or more, the oxide film thickness is sufficiently thick even when the holding time is short (for example, 10 seconds), and the oxide film thickness is thin when the holding time is short. It can be seen that the problem of the present invention is solved.

プレス成形性に優れることから、自動車車体用途を中心に広範な分野で適用できる。   Since it is excellent in press formability, it can be applied in a wide range of fields, mainly for automobile body applications.

実施例で使用した酸化物層形成処理設備の要部を示す図。The figure which shows the principal part of the oxide layer formation processing equipment used in the Example. 摩擦係数測定装置を示す概略正面図。The schematic front view which shows a friction coefficient measuring apparatus. 図2中のビード形状・寸法を示す概略斜視図。The schematic perspective view which shows the bead shape and dimension in FIG. 図2中のビード形状・寸法を示す概略斜視図。The schematic perspective view which shows the bead shape and dimension in FIG. 酸化膜厚への亜鉛イオン濃度の影響を示す図である。(実施例1)It is a figure which shows the influence of the zinc ion concentration on an oxide film thickness. Example 1

符号の説明Explanation of symbols

1 洗浄槽
2 溶液槽
3 絞りロール
4 シャワー水洗装置
5 洗浄槽
6 洗浄槽
7 洗浄槽
8 ドライヤ
S 鋼板
11 摩擦係数測定用試料
12 試料台
13 スライドテーブル
14 ローラ
15 スライドテーブル支持台
16 ビード
17 第1ロードセル
18 第2ロードセル
19 レール
N 押付荷重
F 摺動抵抗力
DESCRIPTION OF SYMBOLS 1 Washing tank 2 Solution tank 3 Squeezing roll 4 Shower water washing apparatus 5 Washing tank 6 Washing tank 7 Washing tank 8 Dryer S Steel plate 11 Friction coefficient measurement sample 12 Sample stand 13 Slide table 14 Roller 15 Slide table support stand 16 Bead 17 First Load cell 18 Second load cell 19 Rail N Pressing load F Sliding resistance

Claims (3)

鋼板に亜鉛系めっきを施した後、水溶液に接触処理し、接触処理終了後1〜60秒間保持し、次いで水洗・乾燥を行うことにより、鋼板表面に酸化物層を形成する亜鉛系めっき鋼板の製造方法において、亜鉛系めっき鋼板を接触処理する前記水溶液は、亜鉛イオン濃度として5〜100g/Lの範囲で亜鉛イオンを含有し、pHが4〜6であり、液温が20〜70℃であることを特徴とする亜鉛系めっき鋼板の製造方法。 After applying zinc-based plating to the steel sheet, contact treatment with the aqueous solution, holding for 1 to 60 seconds after completion of the contact treatment , and then washing with water and drying, thereby forming an oxide layer on the steel sheet surface. In the production method, the aqueous solution for contact-treating a zinc-based plated steel sheet contains zinc ions in a range of 5 to 100 g / L as a zinc ion concentration, has a pH of 4 to 6, and a liquid temperature of 20 to 70 ° C. A method for producing a zinc-based plated steel sheet, comprising: 前記水溶液中には、亜鉛の硫酸塩を含むことを特徴とする請求項1に記載の亜鉛系めっき鋼板の製造方法。   The method for producing a galvanized steel sheet according to claim 1, wherein the aqueous solution contains a sulfate of zinc. 前記水溶液に接触後に鋼板表面に形成する液膜が5〜30g/mであることを特徴とする請求項1または2に記載の亜鉛系めっき鋼板の製造方法。 Method for manufacturing a galvanized steel sheet according to claim 1 or 2 liquid film formed on the surface of the steel sheet after contacting the aqueous solution characterized in that it is a 5 to 30 g / m 2.
JP2008319131A 2008-01-30 2008-12-16 Method for producing galvanized steel sheet Active JP5354165B2 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
JP2008319131A JP5354165B2 (en) 2008-01-30 2008-12-16 Method for producing galvanized steel sheet
CN2009801454920A CN102216493A (en) 2008-12-16 2009-04-22 Galvanized steel sheet and method for manufacturing the same
PCT/JP2009/058426 WO2010070942A1 (en) 2008-12-16 2009-04-22 Galvanized steel sheet and method for manufacturing the same
EP09833249.7A EP2366812B1 (en) 2008-12-16 2009-04-22 Method for manufacturing a galvanized steel sheet
US13/129,504 US20110226387A1 (en) 2008-01-30 2009-04-22 Galvanized steel sheet and method for manufacturing the same
CA2742354A CA2742354C (en) 2008-12-16 2009-04-22 Galvanized steel sheet and method for manufacturing the same
KR1020117010906A KR20110073573A (en) 2008-12-16 2009-04-22 Galvanized steel sheet and method for manufacturing the same
TW098113978A TWI516638B (en) 2008-12-16 2009-04-28 Galvanized steel sheet and manufacturing method thereof

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2008018438 2008-01-30
JP2008018438 2008-01-30
JP2008319131A JP5354165B2 (en) 2008-01-30 2008-12-16 Method for producing galvanized steel sheet

Publications (2)

Publication Number Publication Date
JP2009203547A JP2009203547A (en) 2009-09-10
JP5354165B2 true JP5354165B2 (en) 2013-11-27

Family

ID=41146100

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2008319131A Active JP5354165B2 (en) 2008-01-30 2008-12-16 Method for producing galvanized steel sheet

Country Status (2)

Country Link
US (1) US20110226387A1 (en)
JP (1) JP5354165B2 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102011001140A1 (en) * 2011-03-08 2012-09-13 Thyssenkrupp Steel Europe Ag Flat steel product, method for producing a flat steel product and method for producing a component
JP5962168B2 (en) * 2012-04-20 2016-08-03 Jfeスチール株式会社 Manufacturing method of high-lubrication hot-dip galvanized steel sheet with excellent appearance
JP6256407B2 (en) * 2015-04-13 2018-01-10 Jfeスチール株式会社 Steel sheet and manufacturing method thereof
EP3368616A4 (en) * 2015-10-29 2019-03-13 Electric Power Research Institute, Inc. Methods for creating a zinc-metal oxide layer in metal components for corrosion resistance
WO2019073273A1 (en) 2017-10-12 2019-04-18 Arcelormittal Metal sheet treatment method and metal sheet treated with this method
WO2019073274A1 (en) 2017-10-12 2019-04-18 Arcelormittal Metal sheet treatment method and metal sheet treated with this method
CN114807801B (en) * 2022-04-24 2023-11-24 唐山裕宁实业有限公司 Steel structure surface galvanization equipment for steel structure processing

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3346338B2 (en) * 1999-05-18 2002-11-18 住友金属工業株式会社 Galvanized steel sheet and method for producing the same
KR100603427B1 (en) * 2000-04-24 2006-07-20 제이에프이 스틸 가부시키가이샤 Galvannealed Sheet Steel
JP3807341B2 (en) * 2002-04-18 2006-08-09 Jfeスチール株式会社 Method for producing galvannealed steel sheet
KR100707255B1 (en) * 2003-04-18 2007-04-13 제이에프이 스틸 가부시키가이샤 Hot-dip galvanized steel sheet having excellent press formability and method for producing the same
FR2864552B1 (en) * 2003-12-24 2006-07-21 Usinor SURFACE TREATMENT WITH HYDROXYSULFATE
MX2008013860A (en) * 2006-05-02 2008-11-14 Jfe Steel Corp Process for producing alloyed hot-dip zinc-plated steel sheet and alloyed hot-dip zinc-plated steel sheet.
JP5239570B2 (en) * 2007-09-04 2013-07-17 Jfeスチール株式会社 Galvanized steel sheet

Also Published As

Publication number Publication date
JP2009203547A (en) 2009-09-10
US20110226387A1 (en) 2011-09-22

Similar Documents

Publication Publication Date Title
JP3807341B2 (en) Method for producing galvannealed steel sheet
JP5044976B2 (en) Method for producing alloyed hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet
JP5354165B2 (en) Method for producing galvanized steel sheet
JP2010077456A (en) Hot-dip galvanized steel sheet and method for manufacturing the same
JP4655788B2 (en) Method for producing alloyed hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet
WO2010070942A1 (en) Galvanized steel sheet and method for manufacturing the same
JP4517887B2 (en) Method for producing hot dip galvanized steel sheet and hot dip galvanized steel sheet
JP5347295B2 (en) Zinc-based plated steel sheet and method for producing the same
JP4529592B2 (en) Process for producing alloyed hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet.
JP5044924B2 (en) Method for producing alloyed hot-dip galvanized steel sheet and alloyed hot-dip galvanized steel sheet
JP5593601B2 (en) Alloyed hot-dip galvanized steel sheet and method for producing the same
JP4525252B2 (en) Method for producing galvannealed steel sheet
WO2010070943A1 (en) Galvanized steel sheet and method for manufacturing the same
JP5386842B2 (en) Zinc-based plated steel sheet and method for producing the same
JP4826486B2 (en) Method for producing galvannealed steel sheet
JP5434036B2 (en) Zn-Al-based plated steel sheet and method for producing the same
JP4998658B2 (en) Method for producing galvannealed steel sheet
JP5354166B2 (en) Method for producing galvanized steel sheet
JP5163218B2 (en) Method for producing galvanized steel sheet
JP4604712B2 (en) Method for producing hot dip galvanized steel sheet and hot dip galvanized steel sheet
JP5163217B2 (en) Method for producing galvanized steel sheet
JP5927995B2 (en) Method for producing galvanized steel sheet
JP5961967B2 (en) Method for producing hot-dip galvanized steel sheet

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20110824

RD03 Notification of appointment of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7423

Effective date: 20120321

RD04 Notification of resignation of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7424

Effective date: 20120327

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20130514

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20130711

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20130731

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20130813

R150 Certificate of patent or registration of utility model

Ref document number: 5354165

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250