WO2012165644A1 - Molten zn-al-based alloy-plated steel sheet having excellent corrosion resistance and workability, and method for producing same - Google Patents
Molten zn-al-based alloy-plated steel sheet having excellent corrosion resistance and workability, and method for producing same Download PDFInfo
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- WO2012165644A1 WO2012165644A1 PCT/JP2012/064344 JP2012064344W WO2012165644A1 WO 2012165644 A1 WO2012165644 A1 WO 2012165644A1 JP 2012064344 W JP2012064344 W JP 2012064344W WO 2012165644 A1 WO2012165644 A1 WO 2012165644A1
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
- C23C2/06—Zinc or cadmium or alloys based thereon
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/34—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the shape of the material to be treated
- C23C2/36—Elongated material
- C23C2/40—Plates; Strips
Definitions
- the present invention relates to a hot-dip Zn-Al alloy-plated steel sheet suitable for uses such as architecture, civil engineering, and home appliances and a method for producing the same, and particularly relates to improvement of workability and improvement of corrosion resistance of a processed part.
- hot-dip Zn-based plated steel sheets have been widely used in fields such as building materials, home appliances, and automobiles.
- the hot-dip Zn-based plated steel sheet used in such applications is mainly required to have excellent corrosion resistance.
- a hot-dip Zn-based plated steel sheet is formed into a predetermined shape and used as a member such as a roof, wall or structure.
- it is required to be excellent in workability, and further to be excellent in corrosion resistance of a processed part.
- it is often used without painting, and in that case, it is required to have excellent appearance uniformity and blackening resistance.
- Patent Document 1 proposes a hot-dip Zn-Al alloy-plated steel sheet having a beautiful plated appearance with metallic luster and excellent blackening resistance.
- the steel sheet is immersed in a molten Zn-Al alloy plating bath, then pulled up from the plating bath, and cooled at a cooling rate of up to 250 ° C within a range of 1 to 15 ° C / s.
- the surface of the steel sheet contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.1%, and the balance is molten Zn-- consisting of Zn and inevitable impurities.
- Patent Document 2 describes a technique related to a hot-dip Zn-based plated steel sheet having excellent corrosion resistance.
- the plated steel sheet described in Patent Document 2 contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.2% in mass% on the steel sheet surface.
- a plated steel sheet having a molten Zn—Al-based alloy plating layer containing Zn and inevitable impurities, and further having a Ni concentrated layer at the interface between the plating layer and the base steel sheet.
- Patent Document 1 blackening resistance is mainly improved by using a plating layer having a Zn—Al—Mg composition containing Ni.
- Patent Document 1 does not mention anything about the amount of Fe in the plating layer.
- the plating is performed when processing such as bending is performed. Cracks are likely to occur in the layer. It is conceivable that the plating layer becomes thin at the site where the crack occurs, and the underlying steel sheet is exposed in some cases.
- Patent Document 1 In the plated steel plate manufactured by the technique described in Patent Document 1, there is a problem that the workability is lowered and the corrosion resistance of the processed portion is naturally lowered. Moreover, according to the technique described in patent document 2, it is supposed that the plated steel plate excellent in workability and the process part corrosion resistance will be obtained. However, Patent Document 2 does not mention anything about the amount of Fe in the plating layer. For this reason, similarly to the plated steel sheet manufactured by the technique described in Patent Document 1, when the Fe in the plating bath is excessively taken into the plating layer and subjected to processing such as bending, the plating layer Cracks are likely to occur, and the workability is lowered and the corrosion resistance of the machined part is lowered.
- Patent Document 2 discloses that the penetration temperature of the steel sheet into the plating bath is 450 to 600 ° C., the plating bath temperature is 400 to 550 ° C., and the temperature is controlled to an appropriate temperature according to the plate thickness and line speed.
- An object of this invention is to provide the hot-dip Zn-Al type alloy plating steel plate which is excellent in corrosion resistance and workability which combines the outstanding corrosion resistance and the outstanding workability, and its manufacturing method.
- the present inventors diligently studied various factors affecting the corrosion resistance and workability of a hot-dip Zn-Al alloy-plated steel sheet. As a result, in order to improve the adhesion and corrosion resistance of the plating layer, and further the corrosion resistance after processing, the present inventors have changed the plating bath composition to a plating of a Zn—Al—Mg alloy plating composition containing an appropriate amount of Ni.
- the bath temperature of the plating bath is set to an appropriate range of temperature, and when the steel plate serving as the substrate is invaded into the plating bath, the temperature of the invading steel plate (plate temperature) is within the appropriate range, and It was conceived that the temperature should be adjusted to be higher than the bath temperature of the plating bath.
- the present inventors have found that a Ni-concentrated layer can be formed at an appropriate thickness at the interface between the plating layer and the steel plate (base steel plate) as the substrate.
- the present inventors need to adjust the amount of Fe contained in the plating layer to 2.0 g / m 2 or less per unit area of the plating layer in order to stably improve the workability of the plating layer. I found out.
- the inventors of the present invention have found that Fe contained in the plating layer is one in which Fe in the plating bath is solidified and taken into the plating layer, and the amount of Fe in the plating layer is adjusted to a desired value or less. Found that the Fe concentration in the plating bath may be adjusted appropriately, specifically, 0.05% or less by mass%.
- the present invention has been completed based on such findings and further studies. That is, the gist of the present invention is as follows.
- the steel sheet to be the substrate contains, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, the balance Zn and inevitable impurities Manufacturing of a molten Zn-Al alloy-plated steel sheet that forms a molten Zn-Al-based alloy plating layer on the surface of the steel sheet by intrusion into a hot-dip Zn-Al-based alloy plating bath having a composition consisting of
- the molten Zn—Al alloy plating bath is a plating bath prepared by adjusting Fe to 0.10% or less, and the temperature of the molten Zn—Al alloy plating bath is set to 420 to 520.
- the temperature of the steel sheet penetrating into the molten Zn—Al alloy plating bath is a temperature in the range of 420 to 600 ° C. and equal to or higher than the temperature of the molten Zn—Al alloy plating bath. Corrosion resistance and workability characterized by adjusting Method for producing a molten Zn-Al alloy coated steel sheet excellent.
- the corrosion resistance is improved and the workability is improved, and the effect of being able to easily and inexpensively manufacture a molten Zn-Al alloy-plated steel sheet having both excellent corrosion resistance and excellent workability. Play. Moreover, according to this invention, there exists an effect that the adhesiveness of a plating layer improves.
- molten Zn-Al type alloy plating steel plate (henceforth this invention plating steel plate) is demonstrated.
- the steel plate used as the substrate is infiltrated into a molten Zn-Al alloy plating bath using, for example, a continuous hot-dip Zn plating production facility, and then pulled up and cooled, and a molten Zn-Al alloy is applied to the steel plate surface.
- a plating layer is formed.
- the type and composition of the steel plate used as the substrate are not particularly limited, and can be appropriately selected from known hot-rolled steel plates and cold-rolled steel plates according to the application.
- a steel plate as a substrate is heated to a desired heating temperature using, for example, a continuous hot-dip Zn plating manufacturing facility.
- the heating temperature may be appropriately determined according to the steel sheet to be used, and is not particularly limited. However, in the present invention, when the steel sheet enters the plating bath, it is necessary to adjust the steel plate temperature (plate temperature) to a desired temperature, and at least the desired steel plate temperature (plate temperature) when entering the plating bath. It is necessary to set the heating temperature to ensure the above.
- the steel sheet heated to a predetermined temperature enters a molten Zn—Al alloy plating bath maintained at a predetermined composition and bath temperature, and forms a molten Zn—Al alloy plating layer on the surface.
- the composition of the hot-dip Zn—Al-based alloy plating bath into which the steel sheet penetrates is, in mass%, Al: 3-6%, Mg: 0.2-1.0%, Ni: 0.01-0.10%. And a composition comprising the balance Zn and inevitable impurities.
- the plating bath described above is a plating bath in which Fe is further adjusted to 0.10% or less.
- the reason for limiting the composition of the plating bath is as follows. In addition, the mass% about a composition is described only with%.
- Al 3-6% If the Al contained in the plating bath is less than 3%, the Fe—Al-based alloy layer is easily formed thick at the interface between the obtained plating layer and the underlying steel plate (substrate), and the workability of the plating layer is reduced. On the other hand, when Al is contained in a large amount exceeding 6%, the sacrificial anticorrosive action of Zn in the plating layer is reduced, and the corrosion resistance of the plated steel plate end face portion and the like is lowered. On the other hand, if Al in the plating bath exceeds 6%, top dross mainly composed of Al is likely to be generated, and the appearance properties of the obtained plating layer are deteriorated.
- Mg 0.2 to 1.0% Mg is contained in the plating bath in order to improve the corrosion resistance of the formed plating layer, in particular, the blackening resistance.
- Mg content in the plating bath is less than 0.2%, the effect of improving the corrosion resistance of the resulting plating layer is small.
- Mg in the plating bath is limited to the range of 0.2 to 1.0%.
- Ni 0.01 to 0.10% Ni is contained in the plating bath in order to improve the corrosion resistance of the resulting plating layer. However, if Ni is less than 0.01%, the effect of improving the corrosion resistance is small.
- Ni is contained in a large amount exceeding 0.10%, the surface of the obtained plating layer is excessively activated and easily corroded, and white rust is likely to appear at the initial stage.
- Ni in the plating bath is limited to a range of 0.01 to 0.10%.
- the balance other than the above consists of Zn and unavoidable impurities.
- Fe is further adjusted by mass% to 0.10% or less.
- mass% There is no particular addition of Fe in the plating bath.
- the Fe content contained in the plating bath is taken into the plating layer when the plating bath attached to the steel plate surface solidifies to form a plating layer.
- the alloy phase is formed thick, so that the workability of the plating layer is lowered.
- the bath temperature of the plating bath adjusted to the above composition is adjusted to a temperature in the range of 420 ° C. to 520 ° C.
- the bath temperature of the plating bath is less than 420 ° C., the bath temperature is too low, the viscosity of the plating bath increases, and the predetermined plating treatment cannot be performed.
- the bath temperature of the plating bath is limited to a temperature in the range of 420 ° C. to 520 ° C.
- substrate is penetrate
- the temperature (plate temperature) of the steel sheet entering the plating bath is adjusted to a temperature in the range of 420 to 600 ° C.
- the intruding steel plate temperature is lower than the plating bath temperature, the plating bath temperature gradually decreases, which increases the viscosity of the plating bath and hinders operation.
- the bath temperature of the plating bath gradually increases.
- the temperature (plate temperature) of the steel sheet entering the plating bath is limited to a temperature in the range of 420 to 600 ° C. and higher than the bath temperature of the plating bath.
- the plating bath having the above composition is set to a bath temperature in the above range, and the temperature (plate temperature) of the steel sheet entering the plating bath is a temperature in the range of 420 to 600 ° C.
- the bath temperature of the plating bath Adjusts to the above. Thereby, diffusion of the alloy element occurs at the interface between the plating bath and the steel sheet surface, and the formation of an appropriate Ni concentrated layer at the interface between the plating layer and the steel sheet (substrate) is promoted.
- the formation of the Ni concentrated layer can improve the corrosion resistance even when a scratch that reaches the substrate occurs in the plating layer or when a crack occurs in the plating layer due to processing.
- the Ni concentrated layer thickness can be controlled to an appropriate range of 0.05 to 1 ⁇ m. The steel sheet that has entered the plating bath is then pulled up from the plating bath and cooled.
- the plated steel sheet of the present invention produced by the above-described process has, on at least one surface, mass%, Al: 3.0 to 6.0%, Mg: 0.2 to 1.0%, Ni: 0.01. It has a molten Zn-Al alloy plating layer containing the balance Zn and unavoidable impurities, containing ⁇ 0.10%, Fe adjusted to 2.0 g / m 2 or less, and the interface between the plating layer and the steel plate And a hot-dip Zn—Al-based alloy-plated steel sheet having a Ni enriched layer having a thickness of 0.05 to 1 ⁇ m.
- the reason for limiting the composition of the molten Zn—Al-based alloy plating layer is the same as the reason for limiting the plating bath composition described above, and is therefore omitted.
- the adhesion amount of a hot-dip Zn-Al type alloy plating layer is preferably about 30 to 300 g / m 2 per side.
- the adhesion amount of the plating layer is less than 30 g / m 2 , the plating layer thickness is insufficient and desired corrosion resistance cannot be maintained.
- the plated steel sheet of the present invention has a Ni concentrated layer at the interface between the plating layer and the base steel sheet (substrate). Thereby, even when the crack which reaches a base steel plate (board
- the thickness of the Ni concentrated layer is in the range of 0.05 to 1.0 ⁇ m.
- the thickness of the Ni-concentrated layer is less than 0.05 ⁇ m, the reaction between the plating layer and the base steel plate (substrate) is insufficient, so that the plating adhesion is insufficient.
- the thickness of the Ni concentrated layer formed at the interface between the plating layer and the base steel plate (substrate) is limited to a range of 0.05 to 1.0 ⁇ m.
- the Ni-enriched layer is formed by an alloying reaction between Ni in the plating bath and Fe on the steel plate surface, and appropriately manages the plating bath temperature, the steel plate, and the intrusion plate temperature as described above.
- the thickness of the Ni concentrated layer can be adjusted within a predetermined range.
- a cold-rolled steel plate (plate thickness: 0.5 mm, unannealed) was used as a substrate, and the substrate was heated to the steel plate temperature (sheet temperature) at the time of entry shown in Table 1 when entering the plating bath. Then, the molten Zn—Al alloy plating layer having the adhesion amount shown in Table 2 is formed on the surface of the substrate by infiltrating into a molten Zn—Al alloy plating bath having various compositions and bath temperatures shown in Table 1, pulling up and cooling. Formed. About the obtained molten Zn-Al type alloy plated steel plate, the plating layer was first melt
- the test method was as follows. (1) Microstructure observation of plated layer cross section A specimen for structural observation is collected from the obtained molten Zn-Al alloy-plated steel sheet, the cross section in the plate thickness direction is polished, and a scanning electron microscope (magnification: 2000 times) is used. Then, the structure of the cross section of the plating layer was observed with 10 fields of view or more, Ni was analyzed, the presence or absence of the Ni concentrated layer and the thickness thereof were measured, and the average thickness was calculated.
- Ni-enriched layer refers to a region where a Ni peak is detected by an energy dispersive X-ray analyzer of a scanning electron microscope.
- Evaluation ⁇ Crack generation strain amount is 20% or more Evaluation ⁇ : Crack generation strain amount is 10% or more and less than 20% Evaluation ⁇ : Crack generation strain amount is 5% or more and less than 10% Evaluation ⁇ : Crack generation strain amount is less than 5% (3) Corrosion resistance test of processed part After giving 1R-180 degree bending to the obtained hot-dip Zn-Al system alloy plating steel plate, a salt spray test was carried out based on a rule of JISZ 2371. The salt spray conditions were: spray solution: 5% saline, temperature: 35 ° C., test time: 1000 h. After the test, the surface of the test piece was visually observed to determine the occurrence rate of red rust (area ratio), and the corrosion resistance of the processed part was evaluated. The evaluation criteria were as follows.
- Each of the examples of the present invention is a hot-dip Zn-Al alloy-plated steel sheet excellent in workability and corrosion resistance of the processed part. On the other hand, in the comparative examples that are out of the scope of the present invention, the workability is lowered, the processed portion corrosion resistance is lowered, or both are lowered.
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Abstract
A molten Zn-Al-based alloy plating layer is formed on the surface of a steel sheet by dipping a steel sheet in a molten Zn-Al-based alloy plating bath, which contains, in terms of mass %, 3 to 6% of Al, 0.2 to 1.0% of Mg and 0.01 to 0.10% of Ni and in which the content of Fe is adjusted to 0.10% or less, and then withdrawing and cooling the steel sheet. Here, by adjusting so that the bath temperature of the plating bath is 420 to 520°C and the temperature of the steel sheet dipped into the plating bath is 420 to 600°C and not lower than the bath temperature of the plating bath, a molten Zn-Al-based alloy-plated steel sheet is formed which has excellent workability and corrosion resistance, which has an Fe content in the plating layer of 2.0 g/m2 or lower and which has a Ni-enriched layer having a thickness of 0.05 to 1.0 μm at the interface of the steel sheet and the plating layer.
Description
本発明は、建築、土木、家電等の用途に好適な、溶融Ｚｎ−Ａｌ系合金めっき鋼板およびその製造方法に係り、とくに加工性の向上、および加工部の耐食性の向上に関するものである。
The present invention relates to a hot-dip Zn-Al alloy-plated steel sheet suitable for uses such as architecture, civil engineering, and home appliances and a method for producing the same, and particularly relates to improvement of workability and improvement of corrosion resistance of a processed part.
従来から、建材、家電、自動車等の分野では、溶融Ｚｎ系めっき鋼板が広く利用されている。このような用途で使用される溶融Ｚｎ系めっき鋼板には、主として耐食性に優れることが要求されている。しかし、例えば、建築分野では、溶融Ｚｎ系めっき鋼板を所定形状に成形加工して、屋根、壁あるいは構造体などの部材として使用しており、このような用途向けの溶融Ｚｎ系めっき鋼板には、耐食性に優れていることに加えて、加工性に優れること、さらには加工部の耐食性に優れることが要求されている。また、例えば、建材や家電分野では、無塗装で使用されることも多く、その場合には、外観の均一性や耐黒変性にも優れていることが要求されている。
このような要求に対し、例えば、特許文献１には、金属光沢をもつ美麗なめっき外観と、優れた耐黒変性を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板が提案されている。特許文献１に記載された技術では、鋼板を溶融Ｚｎ−Ａｌ系合金めっき浴に浸漬した後、該めっき浴から引き上げて、２５０℃までの冷却速度で１~１５℃／ｓの範囲で冷却し、鋼板表面に、Ａｌ：１．０~１０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．００５~０．１％を含み、残部がＺｎおよび不可避的不純物からなる溶融Ｚｎ−Ａｌ系合金めっき層を形成し、金属光沢をもつ美麗なめっき外観と、優れた耐黒変性を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板を得るとしている。また、特許文献１に記載された技術では、めっき後の冷却速度を上記した特定の範囲に制御することにより、ＭｇとＮｉの相乗作用によりめっき最表層部へのＮｉの濃化が促進されるとしている。
また、特許文献２には、耐食性に優れた溶融Ｚｎ系めっき鋼板に関する技術が記載されている。特許文献２に記載されためっき鋼板は、鋼板表面に、質量％で、Ａｌ：１．０~１０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．００５~０．２％を含み、残部がＺｎおよび不可避的不純物からなる溶融Ｚｎ−Ａｌ系合金めっき層を有し、さらにめっき層と下地鋼板との界面にＮｉ濃化層を有するめっき鋼板である。これにより、加工性に優れためっき層となり、加工部でのクラックの発生が抑えられ下地鋼板の腐食が抑制されて、優れた加工部耐食性を有するめっき鋼板となるとしている。 Conventionally, hot-dip Zn-based plated steel sheets have been widely used in fields such as building materials, home appliances, and automobiles. The hot-dip Zn-based plated steel sheet used in such applications is mainly required to have excellent corrosion resistance. However, for example, in the construction field, a hot-dip Zn-based plated steel sheet is formed into a predetermined shape and used as a member such as a roof, wall or structure. In addition to being excellent in corrosion resistance, it is required to be excellent in workability, and further to be excellent in corrosion resistance of a processed part. In addition, for example, in the field of building materials and home appliances, it is often used without painting, and in that case, it is required to have excellent appearance uniformity and blackening resistance.
In response to such a demand, for example, Patent Document 1 proposes a hot-dip Zn-Al alloy-plated steel sheet having a beautiful plated appearance with metallic luster and excellent blackening resistance. In the technique described in Patent Document 1, the steel sheet is immersed in a molten Zn-Al alloy plating bath, then pulled up from the plating bath, and cooled at a cooling rate of up to 250 ° C within a range of 1 to 15 ° C / s. The surface of the steel sheet contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.1%, and the balance is molten Zn-- consisting of Zn and inevitable impurities. An Al-based alloy plating layer is formed to obtain a hot-dip Zn-Al-based alloy-plated steel sheet having a beautiful plating appearance with metallic luster and excellent blackening resistance. Further, in the technique described in Patent Document 1, by concentrating the cooling rate after plating to the specific range described above, the concentration of Ni in the outermost layer portion of the plating is promoted by the synergistic action of Mg and Ni. It is said.
Patent Document 2 describes a technique related to a hot-dip Zn-based plated steel sheet having excellent corrosion resistance. The plated steel sheet described in Patent Document 2 contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.2% in mass% on the steel sheet surface. In addition, a plated steel sheet having a molten Zn—Al-based alloy plating layer containing Zn and inevitable impurities, and further having a Ni concentrated layer at the interface between the plating layer and the base steel sheet. Thereby, it becomes the plated layer excellent in workability, generation | occurrence | production of the crack in a process part is suppressed, corrosion of a base steel plate is suppressed, and it is supposed that it will become a plated steel plate which has the outstanding process part corrosion resistance.
このような要求に対し、例えば、特許文献１には、金属光沢をもつ美麗なめっき外観と、優れた耐黒変性を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板が提案されている。特許文献１に記載された技術では、鋼板を溶融Ｚｎ−Ａｌ系合金めっき浴に浸漬した後、該めっき浴から引き上げて、２５０℃までの冷却速度で１~１５℃／ｓの範囲で冷却し、鋼板表面に、Ａｌ：１．０~１０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．００５~０．１％を含み、残部がＺｎおよび不可避的不純物からなる溶融Ｚｎ−Ａｌ系合金めっき層を形成し、金属光沢をもつ美麗なめっき外観と、優れた耐黒変性を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板を得るとしている。また、特許文献１に記載された技術では、めっき後の冷却速度を上記した特定の範囲に制御することにより、ＭｇとＮｉの相乗作用によりめっき最表層部へのＮｉの濃化が促進されるとしている。
また、特許文献２には、耐食性に優れた溶融Ｚｎ系めっき鋼板に関する技術が記載されている。特許文献２に記載されためっき鋼板は、鋼板表面に、質量％で、Ａｌ：１．０~１０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．００５~０．２％を含み、残部がＺｎおよび不可避的不純物からなる溶融Ｚｎ−Ａｌ系合金めっき層を有し、さらにめっき層と下地鋼板との界面にＮｉ濃化層を有するめっき鋼板である。これにより、加工性に優れためっき層となり、加工部でのクラックの発生が抑えられ下地鋼板の腐食が抑制されて、優れた加工部耐食性を有するめっき鋼板となるとしている。 Conventionally, hot-dip Zn-based plated steel sheets have been widely used in fields such as building materials, home appliances, and automobiles. The hot-dip Zn-based plated steel sheet used in such applications is mainly required to have excellent corrosion resistance. However, for example, in the construction field, a hot-dip Zn-based plated steel sheet is formed into a predetermined shape and used as a member such as a roof, wall or structure. In addition to being excellent in corrosion resistance, it is required to be excellent in workability, and further to be excellent in corrosion resistance of a processed part. In addition, for example, in the field of building materials and home appliances, it is often used without painting, and in that case, it is required to have excellent appearance uniformity and blackening resistance.
In response to such a demand, for example, Patent Document 1 proposes a hot-dip Zn-Al alloy-plated steel sheet having a beautiful plated appearance with metallic luster and excellent blackening resistance. In the technique described in Patent Document 1, the steel sheet is immersed in a molten Zn-Al alloy plating bath, then pulled up from the plating bath, and cooled at a cooling rate of up to 250 ° C within a range of 1 to 15 ° C / s. The surface of the steel sheet contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.1%, and the balance is molten Zn-- consisting of Zn and inevitable impurities. An Al-based alloy plating layer is formed to obtain a hot-dip Zn-Al-based alloy-plated steel sheet having a beautiful plating appearance with metallic luster and excellent blackening resistance. Further, in the technique described in Patent Document 1, by concentrating the cooling rate after plating to the specific range described above, the concentration of Ni in the outermost layer portion of the plating is promoted by the synergistic action of Mg and Ni. It is said.
Patent Document 2 describes a technique related to a hot-dip Zn-based plated steel sheet having excellent corrosion resistance. The plated steel sheet described in Patent Document 2 contains Al: 1.0 to 10%, Mg: 0.2 to 1.0%, Ni: 0.005 to 0.2% in mass% on the steel sheet surface. In addition, a plated steel sheet having a molten Zn—Al-based alloy plating layer containing Zn and inevitable impurities, and further having a Ni concentrated layer at the interface between the plating layer and the base steel sheet. Thereby, it becomes the plated layer excellent in workability, generation | occurrence | production of the crack in a process part is suppressed, corrosion of a base steel plate is suppressed, and it is supposed that it will become a plated steel plate which has the outstanding process part corrosion resistance.
特許文献１に記載された技術では、Ｎｉを含有するＺｎ−Ａｌ−Ｍｇ系組成のめっき層とすることにより、主として耐黒変性が向上するとしている。しかし、特許文献１には、めっき層中のＦｅ量についてはなんの言及もない。例えば、めっき浴中に含まれるＦｅが過剰にめっき層中に取り込まれ、めっき層と基板との界面に厚く合金相が形成された場合には、曲げ等の加工を施された際に、めっき層にクラックが発生しやすくなる。クラックが生じた部位では、めっき層が薄くなり、場合によっては下地の鋼板が露出することが考えられる。このため、特許文献１に記載された技術で製造されためっき鋼板では、加工性が低下し、加工部の耐食性が、当然に、低下するという問題があった。
また、特許文献２に記載された技術によれば、加工性に優れ、また加工部耐食性に優れためっき鋼板が得られるとしている。しかし、特許文献２には、めっき層中のＦｅ量についてなんの言及もない。このため、特許文献１に記載された技術で製造されためっき鋼板と同様に、めっき浴中のＦｅが過剰にめっき層中に取り込まれ、例えば曲げ等の加工を施された際に、めっき層にクラックが発生しやすくなり、加工性が低下するとともに、加工部の耐食性が低下するという問題がある。
また、特許文献２には、めっき浴への鋼板の侵入板温４５０~６００℃、めっき浴温度４００~５５０℃の範囲で、板厚、ライン速度に応じてそれらを適正温度に制御する、との記載があるだけで、具体的な製造方法についての明確な記載もなく不明のままである。特許文献２には、しかも製造方法について効果の確認もなされていない。
本発明は、優れた耐食性と優れた加工性とを兼備する、耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板およびその製造方法を提供することを目的とする。 In the technique described in Patent Document 1, blackening resistance is mainly improved by using a plating layer having a Zn—Al—Mg composition containing Ni. However, Patent Document 1 does not mention anything about the amount of Fe in the plating layer. For example, if the Fe contained in the plating bath is excessively taken into the plating layer and a thick alloy phase is formed at the interface between the plating layer and the substrate, the plating is performed when processing such as bending is performed. Cracks are likely to occur in the layer. It is conceivable that the plating layer becomes thin at the site where the crack occurs, and the underlying steel sheet is exposed in some cases. For this reason, in the plated steel plate manufactured by the technique described in Patent Document 1, there is a problem that the workability is lowered and the corrosion resistance of the processed portion is naturally lowered.
Moreover, according to the technique described in patent document 2, it is supposed that the plated steel plate excellent in workability and the process part corrosion resistance will be obtained. However, Patent Document 2 does not mention anything about the amount of Fe in the plating layer. For this reason, similarly to the plated steel sheet manufactured by the technique described in Patent Document 1, when the Fe in the plating bath is excessively taken into the plating layer and subjected to processing such as bending, the plating layer Cracks are likely to occur, and the workability is lowered and the corrosion resistance of the machined part is lowered.
Further, Patent Document 2 discloses that the penetration temperature of the steel sheet into the plating bath is 450 to 600 ° C., the plating bath temperature is 400 to 550 ° C., and the temperature is controlled to an appropriate temperature according to the plate thickness and line speed. However, there is no clear description about a specific manufacturing method, and it remains unclear. In Patent Document 2, the effect of the manufacturing method is not confirmed.
An object of this invention is to provide the hot-dip Zn-Al type alloy plating steel plate which is excellent in corrosion resistance and workability which combines the outstanding corrosion resistance and the outstanding workability, and its manufacturing method.
また、特許文献２に記載された技術によれば、加工性に優れ、また加工部耐食性に優れためっき鋼板が得られるとしている。しかし、特許文献２には、めっき層中のＦｅ量についてなんの言及もない。このため、特許文献１に記載された技術で製造されためっき鋼板と同様に、めっき浴中のＦｅが過剰にめっき層中に取り込まれ、例えば曲げ等の加工を施された際に、めっき層にクラックが発生しやすくなり、加工性が低下するとともに、加工部の耐食性が低下するという問題がある。
また、特許文献２には、めっき浴への鋼板の侵入板温４５０~６００℃、めっき浴温度４００~５５０℃の範囲で、板厚、ライン速度に応じてそれらを適正温度に制御する、との記載があるだけで、具体的な製造方法についての明確な記載もなく不明のままである。特許文献２には、しかも製造方法について効果の確認もなされていない。
本発明は、優れた耐食性と優れた加工性とを兼備する、耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板およびその製造方法を提供することを目的とする。 In the technique described in Patent Document 1, blackening resistance is mainly improved by using a plating layer having a Zn—Al—Mg composition containing Ni. However, Patent Document 1 does not mention anything about the amount of Fe in the plating layer. For example, if the Fe contained in the plating bath is excessively taken into the plating layer and a thick alloy phase is formed at the interface between the plating layer and the substrate, the plating is performed when processing such as bending is performed. Cracks are likely to occur in the layer. It is conceivable that the plating layer becomes thin at the site where the crack occurs, and the underlying steel sheet is exposed in some cases. For this reason, in the plated steel plate manufactured by the technique described in Patent Document 1, there is a problem that the workability is lowered and the corrosion resistance of the processed portion is naturally lowered.
Moreover, according to the technique described in patent document 2, it is supposed that the plated steel plate excellent in workability and the process part corrosion resistance will be obtained. However, Patent Document 2 does not mention anything about the amount of Fe in the plating layer. For this reason, similarly to the plated steel sheet manufactured by the technique described in Patent Document 1, when the Fe in the plating bath is excessively taken into the plating layer and subjected to processing such as bending, the plating layer Cracks are likely to occur, and the workability is lowered and the corrosion resistance of the machined part is lowered.
Further, Patent Document 2 discloses that the penetration temperature of the steel sheet into the plating bath is 450 to 600 ° C., the plating bath temperature is 400 to 550 ° C., and the temperature is controlled to an appropriate temperature according to the plate thickness and line speed. However, there is no clear description about a specific manufacturing method, and it remains unclear. In Patent Document 2, the effect of the manufacturing method is not confirmed.
An object of this invention is to provide the hot-dip Zn-Al type alloy plating steel plate which is excellent in corrosion resistance and workability which combines the outstanding corrosion resistance and the outstanding workability, and its manufacturing method.
本発明者らは、上記した目的を達成するために、溶融Ｚｎ−Ａｌ系合金めっき鋼板の耐食性、加工性に及ぼす各種要因について、鋭意研究した。その結果、本発明者らは、めっき層の密着性、耐食性、さらに加工後の耐食性を向上させるには、めっき浴組成を、Ｎｉを適正量含有するＺｎ−Ａｌ−Ｍｇ系合金めっき組成のめっき浴としたうえで、該めっき浴の浴温を適正範囲の温度とし、該めっき浴に、基板となる鋼板を侵入させる際に、侵入する鋼板の温度（板温）を適正範囲内でかつ、めっき浴の浴温以上に調整することがよいことに想到した。これにより、本発明者らは、めっき層と基板である鋼板（下地鋼板）との界面にＮｉ濃化層を、適正厚さに形成することができることを見出した。
さらに、本発明者らは、めっき層の加工性を安定して向上させるためには、めっき層に含まれるＦｅ量を、めっき層の単位面積当たり２．０ｇ／ｍ２以下に調整する必要があることを見出した。そして、本発明者らは、めっき層に含まれるＦｅは、めっき浴中のＦｅが凝固してめっき層に取り込まれたものであり、めっき層中のＦｅ量を所望の値以下に調整するには、めっき浴のＦｅ濃度を適切に、具体的には質量％で０．０５％以下に、調整すればよいことを見出した。
本発明は、このような知見に基づき、さらに検討を加えて完成されたものである。すなわち、本発明の要旨は次のとおりである。
（１）基板となる鋼板を、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含み、残部Ｚｎおよび不可避的不純物からなる組成を有する溶融Ｚｎ−Ａｌ系合金めっき浴に、侵入させ、引き上げ、冷却して、前記鋼板の表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法であって、前記溶融Ｚｎ−Ａｌ系合金めっき浴を、Ｆｅを０．１０％以下に調整してなるめっき浴としたうえで、該溶融Ｚｎ−Ａｌ系合金めっき浴の温度を４２０~５２０℃の範囲の温度とし、該溶融Ｚｎ−Ａｌ系合金めっき浴中に侵入する前記鋼板の温度を４２０~６００℃の範囲の温度で、かつ前記溶融Ｚｎ−Ａｌ系合金めっき浴の温度以上となるように調整することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法。
（２）基板である鋼板の少なくとも一方の表面に、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含有し、残部Ｚｎおよび不可避的不純物からなる組成の溶融Ｚｎ−Ａｌ系合金めっき層を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板であって、前記溶融Ｚｎ−Ａｌ系合金めっき層が、Ｆｅを２．０ｇ／ｍ２以下に調整してなるめっき層であり、前記溶融Ｚｎ−Ａｌ系合金めっき層と前記鋼板の界面に、厚さ：０．０５~１．０μｍのＮｉ濃化層を有することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板。 In order to achieve the above-mentioned object, the present inventors diligently studied various factors affecting the corrosion resistance and workability of a hot-dip Zn-Al alloy-plated steel sheet. As a result, in order to improve the adhesion and corrosion resistance of the plating layer, and further the corrosion resistance after processing, the present inventors have changed the plating bath composition to a plating of a Zn—Al—Mg alloy plating composition containing an appropriate amount of Ni. In the bath, the bath temperature of the plating bath is set to an appropriate range of temperature, and when the steel plate serving as the substrate is invaded into the plating bath, the temperature of the invading steel plate (plate temperature) is within the appropriate range, and It was conceived that the temperature should be adjusted to be higher than the bath temperature of the plating bath. As a result, the present inventors have found that a Ni-concentrated layer can be formed at an appropriate thickness at the interface between the plating layer and the steel plate (base steel plate) as the substrate.
Furthermore, the present inventors need to adjust the amount of Fe contained in the plating layer to 2.0 g / m 2 or less per unit area of the plating layer in order to stably improve the workability of the plating layer. I found out. The inventors of the present invention have found that Fe contained in the plating layer is one in which Fe in the plating bath is solidified and taken into the plating layer, and the amount of Fe in the plating layer is adjusted to a desired value or less. Found that the Fe concentration in the plating bath may be adjusted appropriately, specifically, 0.05% or less by mass%.
The present invention has been completed based on such findings and further studies. That is, the gist of the present invention is as follows.
(1) The steel sheet to be the substrate contains, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, the balance Zn and inevitable impurities Manufacturing of a molten Zn-Al alloy-plated steel sheet that forms a molten Zn-Al-based alloy plating layer on the surface of the steel sheet by intrusion into a hot-dip Zn-Al-based alloy plating bath having a composition consisting of In this method, the molten Zn—Al alloy plating bath is a plating bath prepared by adjusting Fe to 0.10% or less, and the temperature of the molten Zn—Al alloy plating bath is set to 420 to 520. The temperature of the steel sheet penetrating into the molten Zn—Al alloy plating bath is a temperature in the range of 420 to 600 ° C. and equal to or higher than the temperature of the molten Zn—Al alloy plating bath. Corrosion resistance and workability characterized by adjusting Method for producing a molten Zn-Al alloy coated steel sheet excellent.
(2) On at least one surface of a steel plate as a substrate, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, A molten Zn-Al alloy-plated steel sheet having a molten Zn-Al-based alloy plated layer having a composition comprising the balance Zn and inevitable impurities, wherein the molten Zn-Al-based alloy plated layer contains 2.0 g / m of Fe. It is a plating layer adjusted to 2 or less, and has a Ni-concentrated layer having a thickness of 0.05 to 1.0 μm at the interface between the molten Zn—Al-based alloy plating layer and the steel plate. Hot-dip Zn-Al alloy-plated steel sheet with excellent corrosion resistance and workability.
さらに、本発明者らは、めっき層の加工性を安定して向上させるためには、めっき層に含まれるＦｅ量を、めっき層の単位面積当たり２．０ｇ／ｍ２以下に調整する必要があることを見出した。そして、本発明者らは、めっき層に含まれるＦｅは、めっき浴中のＦｅが凝固してめっき層に取り込まれたものであり、めっき層中のＦｅ量を所望の値以下に調整するには、めっき浴のＦｅ濃度を適切に、具体的には質量％で０．０５％以下に、調整すればよいことを見出した。
本発明は、このような知見に基づき、さらに検討を加えて完成されたものである。すなわち、本発明の要旨は次のとおりである。
（１）基板となる鋼板を、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含み、残部Ｚｎおよび不可避的不純物からなる組成を有する溶融Ｚｎ−Ａｌ系合金めっき浴に、侵入させ、引き上げ、冷却して、前記鋼板の表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法であって、前記溶融Ｚｎ−Ａｌ系合金めっき浴を、Ｆｅを０．１０％以下に調整してなるめっき浴としたうえで、該溶融Ｚｎ−Ａｌ系合金めっき浴の温度を４２０~５２０℃の範囲の温度とし、該溶融Ｚｎ−Ａｌ系合金めっき浴中に侵入する前記鋼板の温度を４２０~６００℃の範囲の温度で、かつ前記溶融Ｚｎ−Ａｌ系合金めっき浴の温度以上となるように調整することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法。
（２）基板である鋼板の少なくとも一方の表面に、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含有し、残部Ｚｎおよび不可避的不純物からなる組成の溶融Ｚｎ−Ａｌ系合金めっき層を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板であって、前記溶融Ｚｎ−Ａｌ系合金めっき層が、Ｆｅを２．０ｇ／ｍ２以下に調整してなるめっき層であり、前記溶融Ｚｎ−Ａｌ系合金めっき層と前記鋼板の界面に、厚さ：０．０５~１．０μｍのＮｉ濃化層を有することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板。 In order to achieve the above-mentioned object, the present inventors diligently studied various factors affecting the corrosion resistance and workability of a hot-dip Zn-Al alloy-plated steel sheet. As a result, in order to improve the adhesion and corrosion resistance of the plating layer, and further the corrosion resistance after processing, the present inventors have changed the plating bath composition to a plating of a Zn—Al—Mg alloy plating composition containing an appropriate amount of Ni. In the bath, the bath temperature of the plating bath is set to an appropriate range of temperature, and when the steel plate serving as the substrate is invaded into the plating bath, the temperature of the invading steel plate (plate temperature) is within the appropriate range, and It was conceived that the temperature should be adjusted to be higher than the bath temperature of the plating bath. As a result, the present inventors have found that a Ni-concentrated layer can be formed at an appropriate thickness at the interface between the plating layer and the steel plate (base steel plate) as the substrate.
Furthermore, the present inventors need to adjust the amount of Fe contained in the plating layer to 2.0 g / m 2 or less per unit area of the plating layer in order to stably improve the workability of the plating layer. I found out. The inventors of the present invention have found that Fe contained in the plating layer is one in which Fe in the plating bath is solidified and taken into the plating layer, and the amount of Fe in the plating layer is adjusted to a desired value or less. Found that the Fe concentration in the plating bath may be adjusted appropriately, specifically, 0.05% or less by mass%.
The present invention has been completed based on such findings and further studies. That is, the gist of the present invention is as follows.
(1) The steel sheet to be the substrate contains, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, the balance Zn and inevitable impurities Manufacturing of a molten Zn-Al alloy-plated steel sheet that forms a molten Zn-Al-based alloy plating layer on the surface of the steel sheet by intrusion into a hot-dip Zn-Al-based alloy plating bath having a composition consisting of In this method, the molten Zn—Al alloy plating bath is a plating bath prepared by adjusting Fe to 0.10% or less, and the temperature of the molten Zn—Al alloy plating bath is set to 420 to 520. The temperature of the steel sheet penetrating into the molten Zn—Al alloy plating bath is a temperature in the range of 420 to 600 ° C. and equal to or higher than the temperature of the molten Zn—Al alloy plating bath. Corrosion resistance and workability characterized by adjusting Method for producing a molten Zn-Al alloy coated steel sheet excellent.
(2) On at least one surface of a steel plate as a substrate, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, A molten Zn-Al alloy-plated steel sheet having a molten Zn-Al-based alloy plated layer having a composition comprising the balance Zn and inevitable impurities, wherein the molten Zn-Al-based alloy plated layer contains 2.0 g / m of Fe. It is a plating layer adjusted to 2 or less, and has a Ni-concentrated layer having a thickness of 0.05 to 1.0 μm at the interface between the molten Zn—Al-based alloy plating layer and the steel plate. Hot-dip Zn-Al alloy-plated steel sheet with excellent corrosion resistance and workability.
本発明によれば、耐食性が向上するとともに加工性も向上し、優れた耐食性と優れた加工性とを兼備する、溶融Ｚｎ−Ａｌ系合金めっき鋼板を容易に、しかも安価に製造できるという効果を奏する。また、本発明によれば、めっき層の密着性が向上するという効果もある。
According to the present invention, the corrosion resistance is improved and the workability is improved, and the effect of being able to easily and inexpensively manufacture a molten Zn-Al alloy-plated steel sheet having both excellent corrosion resistance and excellent workability. Play. Moreover, according to this invention, there exists an effect that the adhesiveness of a plating layer improves.
まず、本発明溶融Ｚｎ−Ａｌ系合金めっき鋼板（以下、本発明めっき鋼板ともいう）の製造方法について説明する。
基板とする鋼板を、例えば、連続式溶融Ｚｎめっき製造設備を利用して、溶融Ｚｎ−Ａｌ系合金めっき浴中に侵入させたのち、引き上げ、冷却して、鋼板表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する。
基板として使用する鋼板は、その種類、組成について、とくに限定する必要はなく、用途に応じて、公知の熱延鋼板、冷延鋼板のなかから適宜選択することができる。
まず、基板である鋼板は、例えば、連続式溶融Ｚｎめっき製造設備を用いて、所望の加熱温度まで加熱される。加熱温度は、使用する鋼板に応じて、適宜決定すればよく、とくに限定する必要はない。ただし、本発明では、鋼板をめっき浴に侵入する際に、鋼板温度（板温）を所望の温度に調整する必要があり、少なくともめっき浴に侵入する際の、所望の鋼板温度（板温）を確保できる加熱温度とする必要がある。
ついで、所定の温度に加熱した鋼板は、所定の組成、浴温に保持された溶融Ｚｎ−Ａｌ系合金めっき浴に侵入し、表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する。
鋼板が侵入する、溶融Ｚｎ−Ａｌ系合金めっき浴の組成は、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含み、残部Ｚｎおよび不可避的不純物からなる組成とする。なお、本発明では、上記しためっき浴は、さらにＦｅを０．１０％以下に調整しためっき浴とする。
めっき浴の組成限定の理由は次のとおりである。なお、組成についての質量％は単に％で記す。
Ａｌ：３~６％
めっき浴中に含まれるＡｌが、３％未満では、得られるめっき層と下地鋼板（基板）との界面にＦｅ−Ａｌ系合金層が厚く形成しやすく、めっき層の加工性が低下する。一方、Ａｌが６％を超えて多量に含有されると、めっき層におけるＺｎの犠牲防食作用が小さくなり、めっき鋼板端面部等の耐食性が低下する。まためっき浴中のＡｌが６％を超えると、Ａｌを主体としたトップドロスが発生しやすくなり、得られるめっき層の外観性状が低下する。また、得られるめっき層の耐黒変性が低下し、またＺｎ−Ａｌ−Ｍｇの三元共晶の形成が多くなり、めっき層の加工性が低下する。このため、めっき浴中のＡｌは３~６％の範囲に限定した。
Ｍｇ：０．２~１．０％
形成されるめっき層の耐食性、とくに耐黒変性向上のために、Ｍｇをめっき浴中に含有させる。めっき浴中のＭｇ含有量が０．２％未満では、得られるめっき層の耐食性の向上効果が少ない。一方、Ｍｇが１．０％を超えると、得られるめっき層中にＺｎ−Ａｌ−Ｍｇ系３元共晶の形成が多くなりすぎて、めっき層の加工性が低下する。このようなことから、めっき浴中のＭｇは０．２~１．０％の範囲に限定した。
Ｎｉ：０．０１~０．１０％
Ｎｉは、得られるめっき層の耐食性向上のために、めっき浴中に含有させるが、Ｎｉが０．０１％未満では耐食性の向上効果が少ない。一方、Ｎｉが０．１０％を超えて多量に含有されると、得られるめっき層の表面が過剰に活性化され、腐食しやすくなり、初期に白錆が出やすくなる。このため、めっき浴中のＮｉは０．０１~０．１０％の範囲に限定した。
上記した以外の残部は、Ｚｎおよび不可避的不純物からなる。
なお、本発明で使用するめっき浴は、さらにＦｅを質量％で、０．１０％以下に調整する。めっき浴中には、Ｆｅ分はとくに添加していない。ただし、めっき浴に浸漬した鋼板から、めっき処理時にＦｅ分が溶け出して、めっき浴中に存在する。めっき浴中に含まれたＦｅ分は、鋼板表面に付着しためっき浴が凝固しめっき層を形成する際にめっき層中に取り込まれる。めっき層中に多量のＦｅが取り込まれると、合金相が厚く形成されるため、めっき層の加工性が低下する。本発明者らの検討によれば、このようなめっき層の加工性低下を抑制するためには、めっき層中に含まれるＦｅ量を所定値（２．０ｇ／ｍ２）以下に調整する必要がある。めっき層中に含まれるＦｅをこのような所定値以下に制御するためには、めっき浴のＦｅ濃度を０．１０％以下に、適切に管理することが重要となる。なお、めっき層中のＦｅ量は、めっき層厚さに依存することから、ここでは、単位面積当たりの含有量（ｇ／ｍ２）で表示することにする。
本発明では、上記したような組成に調整されためっき浴の浴温を４２０℃~５２０℃の範囲の温度に調整する。めっき浴の浴温が４２０℃未満では、浴温が低すぎて、めっき浴の粘性が大きくなり、所定のめっき処理ができなくなる。一方、５２０℃を超えて高温となると、めっき浴の酸化が著しくなり、ドロスの発生が著しくなる。このため、めっき浴の浴温は４２０℃~５２０℃の範囲の温度に限定した。
このような組成、浴温に調整されためっき浴に、基板となる鋼板を侵入させる。
本発明では、めっき浴に侵入する鋼板の温度（板温）を、４２０~６００℃の範囲で、かつめっき浴の浴温以上の温度に調整する。侵入する鋼板の板温が、めっき浴浴温未満では、めっき浴の浴温が次第に低下していくため、めっき浴の粘性が大きくなり操業に支障をきたす。一方、６００℃を超えると、めっき浴の浴温が次第に上昇する。このため、めっき浴に侵入する鋼板の温度（板温）は、４２０~６００℃の範囲でかつ、めっき浴の浴温以上の温度に限定した。
本発明では、上記した組成のめっき浴を上記した範囲の浴温とし、さらにめっき浴に侵入する鋼板の温度（板温）を、４２０~６００℃の範囲の温度で、かつめっき浴の浴温以上となるように調整する。これにより、めっき浴と鋼板表面との界面で合金元素の拡散が生じ、めっき層と鋼板（基板）との界面に適切なＮｉ濃化層の形成が促進される。Ｎｉ濃化層の形成により、めっき層に基板に到達するような傷が生じた場合にも、あるいは加工によりめっき層にクラックが生じた場合にも、耐食性を向上できる。上記した範囲で、めっき浴組成、浴温、及び、侵入する鋼板の板温を調整することにより、Ｎｉ濃化層厚さを、適切な０．０５~１μｍの範囲に制御できる。
めっき浴に侵入した鋼板はついで、めっき浴から引き上げられ、冷却される。
上記した工程で製造される本発明めっき鋼板は、少なくとも一方の表面に、質量％で、Ａｌ：３．０~６．０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含有し、Ｆｅを２．０ｇ／ｍ２以下に調整した、残部Ｚｎおよび不可避的不純物からなる組成の溶融Ｚｎ−Ａｌ系合金めっき層を有し、めっき層と鋼板の界面に、厚さ：０．０５~１μｍのＮｉ濃化層を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板である。
溶融Ｚｎ−Ａｌ系合金めっき層の組成限定理由は、上記しためっき浴組成の限定理由と同じであるため、省略する。なお、溶融Ｚｎ−Ａｌ系合金めっき層の付着量は、通常通り、使途に応じて設定すればよく、とくに限定する必要はない。ただし、溶融Ｚｎ−Ａｌ系合金めっき層の付着量は、片面あたり３０~３００ｇ／ｍ２程度とすることが好ましい。めっき層の付着量が３０ｇ／ｍ２未満では、めっき層厚さが不足し、所望の耐食性を維持できなくなる。一方、３００ｇ／ｍ２を超えると、めっき層厚さが厚くなりすぎて、めっき層が剥離しやすくなる。
本発明めっき鋼板は、めっき層と下地鋼板（基板）との界面にＮｉ濃化層を有する。これにより、めっき層に下地鋼板（基板）に到達するような傷が入った場合や、あるいは、加工によってめっき層にクラックが生じた場合であっても、めっき層の耐食性を維持できる。Ｎｉ濃化層の厚さは、０．０５~１．０μｍの範囲とする。Ｎｉ濃化層の厚さが、０．０５μｍ未満では、めっき層と下地鋼板（基板）との反応が不十分であるため、めっき密着性が不足する。一方、１．０μｍを超えて厚く成長すると、めっき層の加工性が低下する。このようなことから、めっき層と下地鋼板（基板）との界面に形成されるＮｉ濃化層の厚さを０．０５~１．０μｍの範囲に限定した。
なお、Ｎｉ濃化層は、めっき浴中のＮｉと鋼板表面のＦｅとの合金化反応によって形成されるものであり、めっき浴温と鋼板および侵入板温を、上記したように適切に管理することによって、Ｎｉ濃化層の厚さを所定の範囲内に調整することができる。 First, the manufacturing method of this invention molten Zn-Al type alloy plating steel plate (henceforth this invention plating steel plate) is demonstrated.
The steel plate used as the substrate is infiltrated into a molten Zn-Al alloy plating bath using, for example, a continuous hot-dip Zn plating production facility, and then pulled up and cooled, and a molten Zn-Al alloy is applied to the steel plate surface. A plating layer is formed.
The type and composition of the steel plate used as the substrate are not particularly limited, and can be appropriately selected from known hot-rolled steel plates and cold-rolled steel plates according to the application.
First, a steel plate as a substrate is heated to a desired heating temperature using, for example, a continuous hot-dip Zn plating manufacturing facility. The heating temperature may be appropriately determined according to the steel sheet to be used, and is not particularly limited. However, in the present invention, when the steel sheet enters the plating bath, it is necessary to adjust the steel plate temperature (plate temperature) to a desired temperature, and at least the desired steel plate temperature (plate temperature) when entering the plating bath. It is necessary to set the heating temperature to ensure the above.
Next, the steel sheet heated to a predetermined temperature enters a molten Zn—Al alloy plating bath maintained at a predetermined composition and bath temperature, and forms a molten Zn—Al alloy plating layer on the surface.
The composition of the hot-dip Zn—Al-based alloy plating bath into which the steel sheet penetrates is, in mass%, Al: 3-6%, Mg: 0.2-1.0%, Ni: 0.01-0.10%. And a composition comprising the balance Zn and inevitable impurities. In the present invention, the plating bath described above is a plating bath in which Fe is further adjusted to 0.10% or less.
The reason for limiting the composition of the plating bath is as follows. In addition, the mass% about a composition is described only with%.
Al: 3-6%
If the Al contained in the plating bath is less than 3%, the Fe—Al-based alloy layer is easily formed thick at the interface between the obtained plating layer and the underlying steel plate (substrate), and the workability of the plating layer is reduced. On the other hand, when Al is contained in a large amount exceeding 6%, the sacrificial anticorrosive action of Zn in the plating layer is reduced, and the corrosion resistance of the plated steel plate end face portion and the like is lowered. On the other hand, if Al in the plating bath exceeds 6%, top dross mainly composed of Al is likely to be generated, and the appearance properties of the obtained plating layer are deteriorated. Further, the blackening resistance of the obtained plating layer is reduced, and the formation of Zn—Al—Mg ternary eutectic is increased, so that the workability of the plating layer is lowered. For this reason, Al in the plating bath is limited to a range of 3 to 6%.
Mg: 0.2 to 1.0%
Mg is contained in the plating bath in order to improve the corrosion resistance of the formed plating layer, in particular, the blackening resistance. When the Mg content in the plating bath is less than 0.2%, the effect of improving the corrosion resistance of the resulting plating layer is small. On the other hand, when Mg exceeds 1.0%, the formation of Zn—Al—Mg ternary eutectic in the obtained plating layer becomes excessive, and the workability of the plating layer is lowered. For these reasons, Mg in the plating bath is limited to the range of 0.2 to 1.0%.
Ni: 0.01 to 0.10%
Ni is contained in the plating bath in order to improve the corrosion resistance of the resulting plating layer. However, if Ni is less than 0.01%, the effect of improving the corrosion resistance is small. On the other hand, when Ni is contained in a large amount exceeding 0.10%, the surface of the obtained plating layer is excessively activated and easily corroded, and white rust is likely to appear at the initial stage. For this reason, Ni in the plating bath is limited to a range of 0.01 to 0.10%.
The balance other than the above consists of Zn and unavoidable impurities.
In the plating bath used in the present invention, Fe is further adjusted by mass% to 0.10% or less. There is no particular addition of Fe in the plating bath. However, from the steel sheet immersed in the plating bath, the Fe content is dissolved out during the plating process and exists in the plating bath. The Fe content contained in the plating bath is taken into the plating layer when the plating bath attached to the steel plate surface solidifies to form a plating layer. When a large amount of Fe is taken into the plating layer, the alloy phase is formed thick, so that the workability of the plating layer is lowered. According to the study by the present inventors, in order to suppress such a decrease in workability of the plating layer, it is necessary to adjust the amount of Fe contained in the plating layer to a predetermined value (2.0 g / m 2 ) or less. There is. In order to control the Fe contained in the plating layer to such a predetermined value or less, it is important to appropriately manage the Fe concentration of the plating bath to 0.10% or less. Since the amount of Fe in the plating layer depends on the thickness of the plating layer, the content per unit area (g / m 2 ) is displayed here.
In the present invention, the bath temperature of the plating bath adjusted to the above composition is adjusted to a temperature in the range of 420 ° C. to 520 ° C. If the bath temperature of the plating bath is less than 420 ° C., the bath temperature is too low, the viscosity of the plating bath increases, and the predetermined plating treatment cannot be performed. On the other hand, when the temperature is higher than 520 ° C., oxidation of the plating bath becomes remarkable and dross generation becomes remarkable. Therefore, the bath temperature of the plating bath is limited to a temperature in the range of 420 ° C. to 520 ° C.
The steel plate used as a board | substrate is penetrate | invaded into the plating bath adjusted to such a composition and bath temperature.
In the present invention, the temperature (plate temperature) of the steel sheet entering the plating bath is adjusted to a temperature in the range of 420 to 600 ° C. and higher than the bath temperature of the plating bath. If the intruding steel plate temperature is lower than the plating bath temperature, the plating bath temperature gradually decreases, which increases the viscosity of the plating bath and hinders operation. On the other hand, when it exceeds 600 ° C., the bath temperature of the plating bath gradually increases. For this reason, the temperature (plate temperature) of the steel sheet entering the plating bath is limited to a temperature in the range of 420 to 600 ° C. and higher than the bath temperature of the plating bath.
In the present invention, the plating bath having the above composition is set to a bath temperature in the above range, and the temperature (plate temperature) of the steel sheet entering the plating bath is a temperature in the range of 420 to 600 ° C. and the bath temperature of the plating bath. Adjust to the above. Thereby, diffusion of the alloy element occurs at the interface between the plating bath and the steel sheet surface, and the formation of an appropriate Ni concentrated layer at the interface between the plating layer and the steel sheet (substrate) is promoted. The formation of the Ni concentrated layer can improve the corrosion resistance even when a scratch that reaches the substrate occurs in the plating layer or when a crack occurs in the plating layer due to processing. By adjusting the plating bath composition, the bath temperature, and the plate temperature of the invading steel plate within the above range, the Ni concentrated layer thickness can be controlled to an appropriate range of 0.05 to 1 μm.
The steel sheet that has entered the plating bath is then pulled up from the plating bath and cooled.
The plated steel sheet of the present invention produced by the above-described process has, on at least one surface, mass%, Al: 3.0 to 6.0%, Mg: 0.2 to 1.0%, Ni: 0.01. It has a molten Zn-Al alloy plating layer containing the balance Zn and unavoidable impurities, containing ~ 0.10%, Fe adjusted to 2.0 g / m 2 or less, and the interface between the plating layer and the steel plate And a hot-dip Zn—Al-based alloy-plated steel sheet having a Ni enriched layer having a thickness of 0.05 to 1 μm.
The reason for limiting the composition of the molten Zn—Al-based alloy plating layer is the same as the reason for limiting the plating bath composition described above, and is therefore omitted. In addition, what is necessary is just to set the adhesion amount of a hot-dip Zn-Al type alloy plating layer according to a use as usual, and does not need to specifically limit it. However, the adhesion amount of the molten Zn—Al-based alloy plating layer is preferably about 30 to 300 g / m 2 per side. When the adhesion amount of the plating layer is less than 30 g / m 2 , the plating layer thickness is insufficient and desired corrosion resistance cannot be maintained. On the other hand, if it exceeds 300 g / m 2 , the plating layer thickness becomes too thick, and the plating layer is easily peeled off.
The plated steel sheet of the present invention has a Ni concentrated layer at the interface between the plating layer and the base steel sheet (substrate). Thereby, even when the crack which reaches a base steel plate (board | substrate) enters into a plating layer, or when a crack arises in a plating layer by processing, the corrosion resistance of a plating layer can be maintained. The thickness of the Ni concentrated layer is in the range of 0.05 to 1.0 μm. When the thickness of the Ni-concentrated layer is less than 0.05 μm, the reaction between the plating layer and the base steel plate (substrate) is insufficient, so that the plating adhesion is insufficient. On the other hand, when it grows thick exceeding 1.0 micrometer, the workability of a plating layer will fall. For this reason, the thickness of the Ni concentrated layer formed at the interface between the plating layer and the base steel plate (substrate) is limited to a range of 0.05 to 1.0 μm.
The Ni-enriched layer is formed by an alloying reaction between Ni in the plating bath and Fe on the steel plate surface, and appropriately manages the plating bath temperature, the steel plate, and the intrusion plate temperature as described above. Thus, the thickness of the Ni concentrated layer can be adjusted within a predetermined range.
基板とする鋼板を、例えば、連続式溶融Ｚｎめっき製造設備を利用して、溶融Ｚｎ−Ａｌ系合金めっき浴中に侵入させたのち、引き上げ、冷却して、鋼板表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する。
基板として使用する鋼板は、その種類、組成について、とくに限定する必要はなく、用途に応じて、公知の熱延鋼板、冷延鋼板のなかから適宜選択することができる。
まず、基板である鋼板は、例えば、連続式溶融Ｚｎめっき製造設備を用いて、所望の加熱温度まで加熱される。加熱温度は、使用する鋼板に応じて、適宜決定すればよく、とくに限定する必要はない。ただし、本発明では、鋼板をめっき浴に侵入する際に、鋼板温度（板温）を所望の温度に調整する必要があり、少なくともめっき浴に侵入する際の、所望の鋼板温度（板温）を確保できる加熱温度とする必要がある。
ついで、所定の温度に加熱した鋼板は、所定の組成、浴温に保持された溶融Ｚｎ−Ａｌ系合金めっき浴に侵入し、表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する。
鋼板が侵入する、溶融Ｚｎ−Ａｌ系合金めっき浴の組成は、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含み、残部Ｚｎおよび不可避的不純物からなる組成とする。なお、本発明では、上記しためっき浴は、さらにＦｅを０．１０％以下に調整しためっき浴とする。
めっき浴の組成限定の理由は次のとおりである。なお、組成についての質量％は単に％で記す。
Ａｌ：３~６％
めっき浴中に含まれるＡｌが、３％未満では、得られるめっき層と下地鋼板（基板）との界面にＦｅ−Ａｌ系合金層が厚く形成しやすく、めっき層の加工性が低下する。一方、Ａｌが６％を超えて多量に含有されると、めっき層におけるＺｎの犠牲防食作用が小さくなり、めっき鋼板端面部等の耐食性が低下する。まためっき浴中のＡｌが６％を超えると、Ａｌを主体としたトップドロスが発生しやすくなり、得られるめっき層の外観性状が低下する。また、得られるめっき層の耐黒変性が低下し、またＺｎ−Ａｌ−Ｍｇの三元共晶の形成が多くなり、めっき層の加工性が低下する。このため、めっき浴中のＡｌは３~６％の範囲に限定した。
Ｍｇ：０．２~１．０％
形成されるめっき層の耐食性、とくに耐黒変性向上のために、Ｍｇをめっき浴中に含有させる。めっき浴中のＭｇ含有量が０．２％未満では、得られるめっき層の耐食性の向上効果が少ない。一方、Ｍｇが１．０％を超えると、得られるめっき層中にＺｎ−Ａｌ−Ｍｇ系３元共晶の形成が多くなりすぎて、めっき層の加工性が低下する。このようなことから、めっき浴中のＭｇは０．２~１．０％の範囲に限定した。
Ｎｉ：０．０１~０．１０％
Ｎｉは、得られるめっき層の耐食性向上のために、めっき浴中に含有させるが、Ｎｉが０．０１％未満では耐食性の向上効果が少ない。一方、Ｎｉが０．１０％を超えて多量に含有されると、得られるめっき層の表面が過剰に活性化され、腐食しやすくなり、初期に白錆が出やすくなる。このため、めっき浴中のＮｉは０．０１~０．１０％の範囲に限定した。
上記した以外の残部は、Ｚｎおよび不可避的不純物からなる。
なお、本発明で使用するめっき浴は、さらにＦｅを質量％で、０．１０％以下に調整する。めっき浴中には、Ｆｅ分はとくに添加していない。ただし、めっき浴に浸漬した鋼板から、めっき処理時にＦｅ分が溶け出して、めっき浴中に存在する。めっき浴中に含まれたＦｅ分は、鋼板表面に付着しためっき浴が凝固しめっき層を形成する際にめっき層中に取り込まれる。めっき層中に多量のＦｅが取り込まれると、合金相が厚く形成されるため、めっき層の加工性が低下する。本発明者らの検討によれば、このようなめっき層の加工性低下を抑制するためには、めっき層中に含まれるＦｅ量を所定値（２．０ｇ／ｍ２）以下に調整する必要がある。めっき層中に含まれるＦｅをこのような所定値以下に制御するためには、めっき浴のＦｅ濃度を０．１０％以下に、適切に管理することが重要となる。なお、めっき層中のＦｅ量は、めっき層厚さに依存することから、ここでは、単位面積当たりの含有量（ｇ／ｍ２）で表示することにする。
本発明では、上記したような組成に調整されためっき浴の浴温を４２０℃~５２０℃の範囲の温度に調整する。めっき浴の浴温が４２０℃未満では、浴温が低すぎて、めっき浴の粘性が大きくなり、所定のめっき処理ができなくなる。一方、５２０℃を超えて高温となると、めっき浴の酸化が著しくなり、ドロスの発生が著しくなる。このため、めっき浴の浴温は４２０℃~５２０℃の範囲の温度に限定した。
このような組成、浴温に調整されためっき浴に、基板となる鋼板を侵入させる。
本発明では、めっき浴に侵入する鋼板の温度（板温）を、４２０~６００℃の範囲で、かつめっき浴の浴温以上の温度に調整する。侵入する鋼板の板温が、めっき浴浴温未満では、めっき浴の浴温が次第に低下していくため、めっき浴の粘性が大きくなり操業に支障をきたす。一方、６００℃を超えると、めっき浴の浴温が次第に上昇する。このため、めっき浴に侵入する鋼板の温度（板温）は、４２０~６００℃の範囲でかつ、めっき浴の浴温以上の温度に限定した。
本発明では、上記した組成のめっき浴を上記した範囲の浴温とし、さらにめっき浴に侵入する鋼板の温度（板温）を、４２０~６００℃の範囲の温度で、かつめっき浴の浴温以上となるように調整する。これにより、めっき浴と鋼板表面との界面で合金元素の拡散が生じ、めっき層と鋼板（基板）との界面に適切なＮｉ濃化層の形成が促進される。Ｎｉ濃化層の形成により、めっき層に基板に到達するような傷が生じた場合にも、あるいは加工によりめっき層にクラックが生じた場合にも、耐食性を向上できる。上記した範囲で、めっき浴組成、浴温、及び、侵入する鋼板の板温を調整することにより、Ｎｉ濃化層厚さを、適切な０．０５~１μｍの範囲に制御できる。
めっき浴に侵入した鋼板はついで、めっき浴から引き上げられ、冷却される。
上記した工程で製造される本発明めっき鋼板は、少なくとも一方の表面に、質量％で、Ａｌ：３．０~６．０％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含有し、Ｆｅを２．０ｇ／ｍ２以下に調整した、残部Ｚｎおよび不可避的不純物からなる組成の溶融Ｚｎ−Ａｌ系合金めっき層を有し、めっき層と鋼板の界面に、厚さ：０．０５~１μｍのＮｉ濃化層を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板である。
溶融Ｚｎ−Ａｌ系合金めっき層の組成限定理由は、上記しためっき浴組成の限定理由と同じであるため、省略する。なお、溶融Ｚｎ−Ａｌ系合金めっき層の付着量は、通常通り、使途に応じて設定すればよく、とくに限定する必要はない。ただし、溶融Ｚｎ−Ａｌ系合金めっき層の付着量は、片面あたり３０~３００ｇ／ｍ２程度とすることが好ましい。めっき層の付着量が３０ｇ／ｍ２未満では、めっき層厚さが不足し、所望の耐食性を維持できなくなる。一方、３００ｇ／ｍ２を超えると、めっき層厚さが厚くなりすぎて、めっき層が剥離しやすくなる。
本発明めっき鋼板は、めっき層と下地鋼板（基板）との界面にＮｉ濃化層を有する。これにより、めっき層に下地鋼板（基板）に到達するような傷が入った場合や、あるいは、加工によってめっき層にクラックが生じた場合であっても、めっき層の耐食性を維持できる。Ｎｉ濃化層の厚さは、０．０５~１．０μｍの範囲とする。Ｎｉ濃化層の厚さが、０．０５μｍ未満では、めっき層と下地鋼板（基板）との反応が不十分であるため、めっき密着性が不足する。一方、１．０μｍを超えて厚く成長すると、めっき層の加工性が低下する。このようなことから、めっき層と下地鋼板（基板）との界面に形成されるＮｉ濃化層の厚さを０．０５~１．０μｍの範囲に限定した。
なお、Ｎｉ濃化層は、めっき浴中のＮｉと鋼板表面のＦｅとの合金化反応によって形成されるものであり、めっき浴温と鋼板および侵入板温を、上記したように適切に管理することによって、Ｎｉ濃化層の厚さを所定の範囲内に調整することができる。 First, the manufacturing method of this invention molten Zn-Al type alloy plating steel plate (henceforth this invention plating steel plate) is demonstrated.
The steel plate used as the substrate is infiltrated into a molten Zn-Al alloy plating bath using, for example, a continuous hot-dip Zn plating production facility, and then pulled up and cooled, and a molten Zn-Al alloy is applied to the steel plate surface. A plating layer is formed.
The type and composition of the steel plate used as the substrate are not particularly limited, and can be appropriately selected from known hot-rolled steel plates and cold-rolled steel plates according to the application.
First, a steel plate as a substrate is heated to a desired heating temperature using, for example, a continuous hot-dip Zn plating manufacturing facility. The heating temperature may be appropriately determined according to the steel sheet to be used, and is not particularly limited. However, in the present invention, when the steel sheet enters the plating bath, it is necessary to adjust the steel plate temperature (plate temperature) to a desired temperature, and at least the desired steel plate temperature (plate temperature) when entering the plating bath. It is necessary to set the heating temperature to ensure the above.
Next, the steel sheet heated to a predetermined temperature enters a molten Zn—Al alloy plating bath maintained at a predetermined composition and bath temperature, and forms a molten Zn—Al alloy plating layer on the surface.
The composition of the hot-dip Zn—Al-based alloy plating bath into which the steel sheet penetrates is, in mass%, Al: 3-6%, Mg: 0.2-1.0%, Ni: 0.01-0.10%. And a composition comprising the balance Zn and inevitable impurities. In the present invention, the plating bath described above is a plating bath in which Fe is further adjusted to 0.10% or less.
The reason for limiting the composition of the plating bath is as follows. In addition, the mass% about a composition is described only with%.
Al: 3-6%
If the Al contained in the plating bath is less than 3%, the Fe—Al-based alloy layer is easily formed thick at the interface between the obtained plating layer and the underlying steel plate (substrate), and the workability of the plating layer is reduced. On the other hand, when Al is contained in a large amount exceeding 6%, the sacrificial anticorrosive action of Zn in the plating layer is reduced, and the corrosion resistance of the plated steel plate end face portion and the like is lowered. On the other hand, if Al in the plating bath exceeds 6%, top dross mainly composed of Al is likely to be generated, and the appearance properties of the obtained plating layer are deteriorated. Further, the blackening resistance of the obtained plating layer is reduced, and the formation of Zn—Al—Mg ternary eutectic is increased, so that the workability of the plating layer is lowered. For this reason, Al in the plating bath is limited to a range of 3 to 6%.
Mg: 0.2 to 1.0%
Mg is contained in the plating bath in order to improve the corrosion resistance of the formed plating layer, in particular, the blackening resistance. When the Mg content in the plating bath is less than 0.2%, the effect of improving the corrosion resistance of the resulting plating layer is small. On the other hand, when Mg exceeds 1.0%, the formation of Zn—Al—Mg ternary eutectic in the obtained plating layer becomes excessive, and the workability of the plating layer is lowered. For these reasons, Mg in the plating bath is limited to the range of 0.2 to 1.0%.
Ni: 0.01 to 0.10%
Ni is contained in the plating bath in order to improve the corrosion resistance of the resulting plating layer. However, if Ni is less than 0.01%, the effect of improving the corrosion resistance is small. On the other hand, when Ni is contained in a large amount exceeding 0.10%, the surface of the obtained plating layer is excessively activated and easily corroded, and white rust is likely to appear at the initial stage. For this reason, Ni in the plating bath is limited to a range of 0.01 to 0.10%.
The balance other than the above consists of Zn and unavoidable impurities.
In the plating bath used in the present invention, Fe is further adjusted by mass% to 0.10% or less. There is no particular addition of Fe in the plating bath. However, from the steel sheet immersed in the plating bath, the Fe content is dissolved out during the plating process and exists in the plating bath. The Fe content contained in the plating bath is taken into the plating layer when the plating bath attached to the steel plate surface solidifies to form a plating layer. When a large amount of Fe is taken into the plating layer, the alloy phase is formed thick, so that the workability of the plating layer is lowered. According to the study by the present inventors, in order to suppress such a decrease in workability of the plating layer, it is necessary to adjust the amount of Fe contained in the plating layer to a predetermined value (2.0 g / m 2 ) or less. There is. In order to control the Fe contained in the plating layer to such a predetermined value or less, it is important to appropriately manage the Fe concentration of the plating bath to 0.10% or less. Since the amount of Fe in the plating layer depends on the thickness of the plating layer, the content per unit area (g / m 2 ) is displayed here.
In the present invention, the bath temperature of the plating bath adjusted to the above composition is adjusted to a temperature in the range of 420 ° C. to 520 ° C. If the bath temperature of the plating bath is less than 420 ° C., the bath temperature is too low, the viscosity of the plating bath increases, and the predetermined plating treatment cannot be performed. On the other hand, when the temperature is higher than 520 ° C., oxidation of the plating bath becomes remarkable and dross generation becomes remarkable. Therefore, the bath temperature of the plating bath is limited to a temperature in the range of 420 ° C. to 520 ° C.
The steel plate used as a board | substrate is penetrate | invaded into the plating bath adjusted to such a composition and bath temperature.
In the present invention, the temperature (plate temperature) of the steel sheet entering the plating bath is adjusted to a temperature in the range of 420 to 600 ° C. and higher than the bath temperature of the plating bath. If the intruding steel plate temperature is lower than the plating bath temperature, the plating bath temperature gradually decreases, which increases the viscosity of the plating bath and hinders operation. On the other hand, when it exceeds 600 ° C., the bath temperature of the plating bath gradually increases. For this reason, the temperature (plate temperature) of the steel sheet entering the plating bath is limited to a temperature in the range of 420 to 600 ° C. and higher than the bath temperature of the plating bath.
In the present invention, the plating bath having the above composition is set to a bath temperature in the above range, and the temperature (plate temperature) of the steel sheet entering the plating bath is a temperature in the range of 420 to 600 ° C. and the bath temperature of the plating bath. Adjust to the above. Thereby, diffusion of the alloy element occurs at the interface between the plating bath and the steel sheet surface, and the formation of an appropriate Ni concentrated layer at the interface between the plating layer and the steel sheet (substrate) is promoted. The formation of the Ni concentrated layer can improve the corrosion resistance even when a scratch that reaches the substrate occurs in the plating layer or when a crack occurs in the plating layer due to processing. By adjusting the plating bath composition, the bath temperature, and the plate temperature of the invading steel plate within the above range, the Ni concentrated layer thickness can be controlled to an appropriate range of 0.05 to 1 μm.
The steel sheet that has entered the plating bath is then pulled up from the plating bath and cooled.
The plated steel sheet of the present invention produced by the above-described process has, on at least one surface, mass%, Al: 3.0 to 6.0%, Mg: 0.2 to 1.0%, Ni: 0.01. It has a molten Zn-Al alloy plating layer containing the balance Zn and unavoidable impurities, containing ~ 0.10%, Fe adjusted to 2.0 g / m 2 or less, and the interface between the plating layer and the steel plate And a hot-dip Zn—Al-based alloy-plated steel sheet having a Ni enriched layer having a thickness of 0.05 to 1 μm.
The reason for limiting the composition of the molten Zn—Al-based alloy plating layer is the same as the reason for limiting the plating bath composition described above, and is therefore omitted. In addition, what is necessary is just to set the adhesion amount of a hot-dip Zn-Al type alloy plating layer according to a use as usual, and does not need to specifically limit it. However, the adhesion amount of the molten Zn—Al-based alloy plating layer is preferably about 30 to 300 g / m 2 per side. When the adhesion amount of the plating layer is less than 30 g / m 2 , the plating layer thickness is insufficient and desired corrosion resistance cannot be maintained. On the other hand, if it exceeds 300 g / m 2 , the plating layer thickness becomes too thick, and the plating layer is easily peeled off.
The plated steel sheet of the present invention has a Ni concentrated layer at the interface between the plating layer and the base steel sheet (substrate). Thereby, even when the crack which reaches a base steel plate (board | substrate) enters into a plating layer, or when a crack arises in a plating layer by processing, the corrosion resistance of a plating layer can be maintained. The thickness of the Ni concentrated layer is in the range of 0.05 to 1.0 μm. When the thickness of the Ni-concentrated layer is less than 0.05 μm, the reaction between the plating layer and the base steel plate (substrate) is insufficient, so that the plating adhesion is insufficient. On the other hand, when it grows thick exceeding 1.0 micrometer, the workability of a plating layer will fall. For this reason, the thickness of the Ni concentrated layer formed at the interface between the plating layer and the base steel plate (substrate) is limited to a range of 0.05 to 1.0 μm.
The Ni-enriched layer is formed by an alloying reaction between Ni in the plating bath and Fe on the steel plate surface, and appropriately manages the plating bath temperature, the steel plate, and the intrusion plate temperature as described above. Thus, the thickness of the Ni concentrated layer can be adjusted within a predetermined range.
冷延鋼板（板厚：０．５ｍｍ、未焼鈍）を基板とし、該基板を、めっき浴に侵入する際に、表１に示す侵入時の鋼板温度（板温）となるように、加熱したのち、表１に示す各種組成、浴温の溶融Ｚｎ−Ａｌ系合金めっき浴に侵入させ、引き上げ、冷却して、基板表面に、表２に示す付着量の溶融Ｚｎ−Ａｌ系合金めっき層を形成した。得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板について、まず、めっき層を溶解して、常法により、めっき層の成分を分析した。また、得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板について、めっき層の断面の組織観察、加工性試験、及び、加工部の耐食性試験を実施した。試験方法は次のとおりとした。
（１）めっき層断面の組織観察
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板から組織観察用試験片を採取し、板厚方向断面を研磨し、走査型電子顕微鏡（倍率：２０００倍）を用いて、１０視野以上で、めっき層断面の組織を観察し、Ｎｉを分析して、Ｎｉ濃化層の有無と、その厚さを測定し、平均厚さを算出した。なお、「Ｎｉ濃化層」とは、走査型電子顕微鏡のエネルギー分散型Ｘ線分析装置でＮｉのピークが検出される領域をいうものとする。
（２）加工性試験
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板から試験片ＪＩＳ５号引張試験片を採取して、引張試験を実施した。試験中に、目視でめっき層表面を観察し、めっき層表面にクラックが確認できる歪量（クラック発生歪量）を求め、めっき鋼板の加工性を評価した。評価基準は下記のとおりとした。
評価◎：クラック発生歪量が２０％以上
評価○：クラック発生歪量が１０％以上２０％未満
評価△：クラック発生歪量が５％以上１０％未満
評価×：クラック発生歪量が５％未満
（３）加工部の耐食性試験
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板に１Ｒ−１８０°曲げを付与したのち、ＪＩＳＺ ２３７１の規定に準拠して塩水噴霧試験を実施した。塩水噴霧条件は、噴霧液：５％食塩水、温度：３５℃、試験時間：１０００ｈとした。試験後、試験片表面を目視で観察し、赤錆発生率（面積率）を求め、加工部の耐食性を評価した。評価の基準は次のとおりとした。
評点○：赤錆発生なし
評価△：赤錆発生率１~５０％
評点×：赤錆発生率５１％以上
得られた結果を表２に示す。
本発明例はいずれも、加工性、加工部耐食性に優れた溶融Ｚｎ−Ａｌ系合金めっき鋼板となっている。一方、本発明の範囲を外れる比較例は、加工性が低下しているか、加工部耐食性が低下しているか、あるいは両者とも低下している。
A cold-rolled steel plate (plate thickness: 0.5 mm, unannealed) was used as a substrate, and the substrate was heated to the steel plate temperature (sheet temperature) at the time of entry shown in Table 1 when entering the plating bath. Then, the molten Zn—Al alloy plating layer having the adhesion amount shown in Table 2 is formed on the surface of the substrate by infiltrating into a molten Zn—Al alloy plating bath having various compositions and bath temperatures shown in Table 1, pulling up and cooling. Formed. About the obtained molten Zn-Al type alloy plated steel plate, the plating layer was first melt | dissolved and the component of the plating layer was analyzed by the conventional method. Moreover, about the obtained hot-dip Zn-Al type alloy plated steel sheet, the structure observation of the cross section of the plating layer, the workability test, and the corrosion resistance test of the processed part were performed. The test method was as follows.
(1) Microstructure observation of plated layer cross section A specimen for structural observation is collected from the obtained molten Zn-Al alloy-plated steel sheet, the cross section in the plate thickness direction is polished, and a scanning electron microscope (magnification: 2000 times) is used. Then, the structure of the cross section of the plating layer was observed with 10 fields of view or more, Ni was analyzed, the presence or absence of the Ni concentrated layer and the thickness thereof were measured, and the average thickness was calculated. The “Ni-enriched layer” refers to a region where a Ni peak is detected by an energy dispersive X-ray analyzer of a scanning electron microscope.
(2) Workability test A test piece JIS No. 5 tensile test piece was sampled from the obtained molten Zn-Al alloy-plated steel sheet and subjected to a tensile test. During the test, the surface of the plating layer was visually observed, the amount of strain (crack generation strain amount) at which cracks could be confirmed on the surface of the plating layer was determined, and the workability of the plated steel sheet was evaluated. The evaluation criteria were as follows.
Evaluation ◎: Crack generation strain amount is 20% or more Evaluation ○: Crack generation strain amount is 10% or more and less than 20% Evaluation Δ: Crack generation strain amount is 5% or more and less than 10% Evaluation ×: Crack generation strain amount is less than 5% (3) Corrosion resistance test of processed part After giving 1R-180 degree bending to the obtained hot-dip Zn-Al system alloy plating steel plate, a salt spray test was carried out based on a rule of JISZ 2371. The salt spray conditions were: spray solution: 5% saline, temperature: 35 ° C., test time: 1000 h. After the test, the surface of the test piece was visually observed to determine the occurrence rate of red rust (area ratio), and the corrosion resistance of the processed part was evaluated. The evaluation criteria were as follows.
Rating ○: No red rust evaluation △: Red rust occurrence rate 1-50%
Score x: Table 2 shows the results obtained for a red rust occurrence rate of 51% or more.
Each of the examples of the present invention is a hot-dip Zn-Al alloy-plated steel sheet excellent in workability and corrosion resistance of the processed part. On the other hand, in the comparative examples that are out of the scope of the present invention, the workability is lowered, the processed portion corrosion resistance is lowered, or both are lowered.
（１）めっき層断面の組織観察
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板から組織観察用試験片を採取し、板厚方向断面を研磨し、走査型電子顕微鏡（倍率：２０００倍）を用いて、１０視野以上で、めっき層断面の組織を観察し、Ｎｉを分析して、Ｎｉ濃化層の有無と、その厚さを測定し、平均厚さを算出した。なお、「Ｎｉ濃化層」とは、走査型電子顕微鏡のエネルギー分散型Ｘ線分析装置でＮｉのピークが検出される領域をいうものとする。
（２）加工性試験
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板から試験片ＪＩＳ５号引張試験片を採取して、引張試験を実施した。試験中に、目視でめっき層表面を観察し、めっき層表面にクラックが確認できる歪量（クラック発生歪量）を求め、めっき鋼板の加工性を評価した。評価基準は下記のとおりとした。
評価◎：クラック発生歪量が２０％以上
評価○：クラック発生歪量が１０％以上２０％未満
評価△：クラック発生歪量が５％以上１０％未満
評価×：クラック発生歪量が５％未満
（３）加工部の耐食性試験
得られた溶融Ｚｎ−Ａｌ系合金めっき鋼板に１Ｒ−１８０°曲げを付与したのち、ＪＩＳＺ ２３７１の規定に準拠して塩水噴霧試験を実施した。塩水噴霧条件は、噴霧液：５％食塩水、温度：３５℃、試験時間：１０００ｈとした。試験後、試験片表面を目視で観察し、赤錆発生率（面積率）を求め、加工部の耐食性を評価した。評価の基準は次のとおりとした。
評点○：赤錆発生なし
評価△：赤錆発生率１~５０％
評点×：赤錆発生率５１％以上
得られた結果を表２に示す。
(1) Microstructure observation of plated layer cross section A specimen for structural observation is collected from the obtained molten Zn-Al alloy-plated steel sheet, the cross section in the plate thickness direction is polished, and a scanning electron microscope (magnification: 2000 times) is used. Then, the structure of the cross section of the plating layer was observed with 10 fields of view or more, Ni was analyzed, the presence or absence of the Ni concentrated layer and the thickness thereof were measured, and the average thickness was calculated. The “Ni-enriched layer” refers to a region where a Ni peak is detected by an energy dispersive X-ray analyzer of a scanning electron microscope.
(2) Workability test A test piece JIS No. 5 tensile test piece was sampled from the obtained molten Zn-Al alloy-plated steel sheet and subjected to a tensile test. During the test, the surface of the plating layer was visually observed, the amount of strain (crack generation strain amount) at which cracks could be confirmed on the surface of the plating layer was determined, and the workability of the plated steel sheet was evaluated. The evaluation criteria were as follows.
Evaluation ◎: Crack generation strain amount is 20% or more Evaluation ○: Crack generation strain amount is 10% or more and less than 20% Evaluation Δ: Crack generation strain amount is 5% or more and less than 10% Evaluation ×: Crack generation strain amount is less than 5% (3) Corrosion resistance test of processed part After giving 1R-180 degree bending to the obtained hot-dip Zn-Al system alloy plating steel plate, a salt spray test was carried out based on a rule of JISZ 2371. The salt spray conditions were: spray solution: 5% saline, temperature: 35 ° C., test time: 1000 h. After the test, the surface of the test piece was visually observed to determine the occurrence rate of red rust (area ratio), and the corrosion resistance of the processed part was evaluated. The evaluation criteria were as follows.
Rating ○: No red rust evaluation △: Red rust occurrence rate 1-50%
Score x: Table 2 shows the results obtained for a red rust occurrence rate of 51% or more.
Claims (2)
- 基板となる鋼板を、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含み、残部Ｚｎおよび不可避的不純物からなる組成を有する溶融Ｚｎ−Ａｌ系合金めっき浴に、侵入させ、引き上げ、冷却して、前記鋼板の表面に溶融Ｚｎ−Ａｌ系合金めっき層を形成する溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法であって、
前記溶融Ｚｎ−Ａｌ系合金めっき浴を、Ｆｅを０．１％以下に調整してなるめっき浴としたうえで、該溶融Ｚｎ−Ａｌ系合金めっき浴の温度を４２０~５２０℃の範囲の温度とし、該溶融Ｚｎ−Ａｌ系合金めっき浴中に侵入する前記鋼板の温度を４２０~６００℃の範囲の温度で、かつ前記溶融Ｚｎ−Ａｌ系合金めっき浴の温度以上となるように調整することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板の製造方法。 The steel sheet used as the substrate contains, in mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, and the balance consisting of the balance Zn and inevitable impurities. A hot-dip Zn-Al alloy-plated steel sheet is formed by forming a molten Zn-Al alloy-plated layer on the surface of the steel sheet by intrusion into a molten Zn-Al-based alloy plating bath having And
The molten Zn-Al alloy plating bath is a plating bath prepared by adjusting Fe to 0.1% or less, and the temperature of the molten Zn-Al alloy plating bath is a temperature in the range of 420 to 520 ° C. And adjusting the temperature of the steel sheet penetrating into the molten Zn-Al alloy plating bath to a temperature in the range of 420 to 600 ° C. and higher than the temperature of the molten Zn—Al alloy plating bath. The manufacturing method of the hot dip Zn-Al system alloy plating steel plate which is excellent in corrosion resistance and workability characterized by these. - 基板である鋼板の少なくとも一方の表面に、質量％で、Ａｌ：３~６％、Ｍｇ：０．２~１．０％、Ｎｉ：０．０１~０．１０％を含有し、残部Ｚｎおよび不可避的不純物からなる組成の溶融Ｚｎ−Ａｌ系合金めっき層を有する溶融Ｚｎ−Ａｌ系合金めっき鋼板であって、
前記溶融Ｚｎ−Ａｌ系合金めっき層が、Ｆｅを２．０ｇ／ｍ２以下に調整してなるめっき層であり、前記溶融Ｚｎ−Ａｌ系合金めっき層と前記鋼板の界面に、厚さ：０．０５~１．０μｍのＮｉ濃化層を有することを特徴とする耐食性と加工性に優れる溶融Ｚｎ−Ａｌ系合金めっき鋼板。 At least one surface of a steel plate as a substrate contains, by mass%, Al: 3 to 6%, Mg: 0.2 to 1.0%, Ni: 0.01 to 0.10%, the balance Zn and A hot-dip Zn-Al-based alloy-plated steel sheet having a hot-dip Zn-Al-based alloy plating layer having a composition comprising inevitable impurities,
The molten Zn—Al-based alloy plating layer is a plating layer obtained by adjusting Fe to 2.0 g / m 2 or less, and the thickness is 0 at the interface between the molten Zn—Al-based alloy plating layer and the steel plate. A hot-dip Zn-Al alloy-plated steel sheet excellent in corrosion resistance and workability, characterized by having a Ni-enriched layer of .05 to 1.0 μm.
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| KR1020137029051A KR101598677B1 (en) | 2011-05-30 | 2012-05-29 | Molten zn-al-based alloy-plated steel sheet having excellent corrosion resistance and workability, and method for producing same |
| AU2012263323A AU2012263323B2 (en) | 2011-05-30 | 2012-05-29 | Molten Zn-Al-based alloy-plated steel sheet having excellent corrosion resistance and workability, and method for producing same |
| CN201280026450.7A CN103562430B (en) | 2011-05-30 | 2012-05-29 | The melting Zn-Al system alloy plating steel plate of erosion resistance and excellent in workability and manufacture method thereof |
| SG2013084314A SG194952A1 (en) | 2011-05-30 | 2012-05-29 | Molten zn-al-based alloy-plated steel sheet having excellent corrosion resistance and workability, and method for producing same |
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| JP2011120550A JP5649179B2 (en) | 2011-05-30 | 2011-05-30 | Hot-dip Zn-Al alloy-plated steel sheet with excellent corrosion resistance and workability and method for producing the same |
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| WO2015052572A1 (en) * | 2013-10-09 | 2015-04-16 | ArcelorMittal Investigación y Desarrollo, S.L. | Sheet metal having a znaimg coating and improved flexibility and corresponding production method |
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| WO2016162982A1 (en) * | 2015-04-08 | 2016-10-13 | 新日鐵住金株式会社 | Zn-Al-Mg-PLATED STEEL SHEET AND METHOD FOR MANUFACTURING Zn-Al-Mg-PLATED STEEL SHEET |
| WO2017057638A1 (en) * | 2015-09-29 | 2017-04-06 | 新日鐵住金株式会社 | Mg-containing zn-alloy-coated steel material |
| HUE063186T2 (en) * | 2017-03-17 | 2023-12-28 | Nippon Steel Corp | Coated steel sheet |
| KR102297298B1 (en) * | 2019-12-06 | 2021-09-03 | 주식회사 포스코 | Galvanizing steel sheet having excelent bendability and corrosion resistance, and manufacturing method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0688178A (en) * | 1992-09-04 | 1994-03-29 | Sumitomo Metal Ind Ltd | Method for removing dross |
| JP2001262303A (en) * | 2000-03-21 | 2001-09-26 | Kawasaki Steel Corp | Method for producing alloyed galvanized steel sheet and galvannealed steel sheet excellent in hot dip metal coated property |
| JP2010255084A (en) * | 2009-04-28 | 2010-11-11 | Jfe Galvanizing & Coating Co Ltd | HOT-DIP Zn COATED STEEL SHEET |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2005146339A (en) * | 2003-11-14 | 2005-06-09 | Nisshin Steel Co Ltd | HOT DIP Al-CONTAINING GALVANNEALED STEEL SHEET HAVING EXCELLENT BLACKENING RESISTANCE |
| JP5101249B2 (en) * | 2006-11-10 | 2012-12-19 | Ｊｆｅ鋼板株式会社 | Hot-dip Zn-Al alloy-plated steel sheet and method for producing the same |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0688178A (en) * | 1992-09-04 | 1994-03-29 | Sumitomo Metal Ind Ltd | Method for removing dross |
| JP2001262303A (en) * | 2000-03-21 | 2001-09-26 | Kawasaki Steel Corp | Method for producing alloyed galvanized steel sheet and galvannealed steel sheet excellent in hot dip metal coated property |
| JP2010255084A (en) * | 2009-04-28 | 2010-11-11 | Jfe Galvanizing & Coating Co Ltd | HOT-DIP Zn COATED STEEL SHEET |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015052572A1 (en) * | 2013-10-09 | 2015-04-16 | ArcelorMittal Investigación y Desarrollo, S.L. | Sheet metal having a znaimg coating and improved flexibility and corresponding production method |
| WO2015052546A1 (en) * | 2013-10-09 | 2015-04-16 | ArcelorMittal Investigación y Desarrollo, S.L. | Sheet metal having a znaimg coating and improved flexibility and corresponding production method |
| CN105829568A (en) * | 2013-10-09 | 2016-08-03 | 安赛乐米塔尔公司 | Sheet metal having a ZnAlMg coating and improved flexibility and corresponding production method |
| EA030933B1 (en) * | 2013-10-09 | 2018-10-31 | Арселормиттал | METAL SHEET HAVING A ZnAlMg COATING AND IMPROVED FLEXIBILITY AND CORRESPONDING MANUFACTURING PROCESS |
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| AU2012263323A1 (en) | 2013-11-21 |
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| KR101598677B1 (en) | 2016-02-29 |
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| CN103562430B (en) | 2015-11-25 |
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