JP2020007585A - HOT-DIP Al-Si BASED PLATED STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - Google Patents
HOT-DIP Al-Si BASED PLATED STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME Download PDFInfo
- Publication number
- JP2020007585A JP2020007585A JP2018127468A JP2018127468A JP2020007585A JP 2020007585 A JP2020007585 A JP 2020007585A JP 2018127468 A JP2018127468 A JP 2018127468A JP 2018127468 A JP2018127468 A JP 2018127468A JP 2020007585 A JP2020007585 A JP 2020007585A
- Authority
- JP
- Japan
- Prior art keywords
- steel sheet
- dip
- hot
- less
- plated steel
- 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.)
- Granted
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 59
- 239000010959 steel Substances 0.000 title claims abstract description 59
- 229910018125 Al-Si Inorganic materials 0.000 title claims abstract description 40
- 229910018520 Al—Si Inorganic materials 0.000 title claims abstract description 40
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title abstract description 5
- 238000007747 plating Methods 0.000 claims abstract description 40
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 16
- 239000000956 alloy Substances 0.000 claims abstract description 16
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 8
- 229910052802 copper Inorganic materials 0.000 claims abstract description 8
- 229910052742 iron Inorganic materials 0.000 claims abstract description 8
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 8
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 8
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 8
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 8
- 238000001816 cooling Methods 0.000 claims description 13
- 239000012535 impurity Substances 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 238000002441 X-ray diffraction Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 abstract description 26
- 239000010410 layer Substances 0.000 description 32
- 238000006243 chemical reaction Methods 0.000 description 22
- 239000011248 coating agent Substances 0.000 description 19
- 238000000576 coating method Methods 0.000 description 19
- 230000007797 corrosion Effects 0.000 description 19
- 238000005260 corrosion Methods 0.000 description 19
- 239000000203 mixture Substances 0.000 description 12
- 239000013078 crystal Substances 0.000 description 6
- 238000004070 electrodeposition Methods 0.000 description 6
- 238000011156 evaluation Methods 0.000 description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000007654 immersion Methods 0.000 description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 5
- 239000011701 zinc Substances 0.000 description 5
- 238000010422 painting Methods 0.000 description 4
- 230000000007 visual effect Effects 0.000 description 4
- 230000008961 swelling Effects 0.000 description 3
- LRXTYHSAJDENHV-UHFFFAOYSA-H zinc phosphate Chemical compound [Zn+2].[Zn+2].[Zn+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O LRXTYHSAJDENHV-UHFFFAOYSA-H 0.000 description 3
- 229910000165 zinc phosphate Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000010960 cold rolled steel Substances 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011737 fluorine Substances 0.000 description 2
- 229910052731 fluorine Inorganic materials 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 238000000550 scanning electron microscopy energy dispersive X-ray spectroscopy Methods 0.000 description 2
- 238000012764 semi-quantitative analysis Methods 0.000 description 2
- 238000010008 shearing Methods 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000004035 construction material Substances 0.000 description 1
- SOCTUWSJJQCPFX-UHFFFAOYSA-N dichromate(2-) Chemical compound [O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O SOCTUWSJJQCPFX-UHFFFAOYSA-N 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000002828 fuel tank Substances 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Abstract
Description
本発明は、溶融Ａｌ-Ｓｉ系めっき鋼板及びその製造方法に関する。 The present invention relates to a hot-dip Al-Si plated steel sheet and a method for producing the same.
耐食性に優れる溶融Ａｌ-Ｓｉ系めっき鋼板は、長期間屋外に曝される屋根や壁等の建材分野を中心に需要が伸び、近年は自動車分野においても優れた耐熱性を活かしてマフラーや燃料タンク等の特定部品で使用されている。特に自動車分野においては、地球温暖化対策の一環として、車体を軽量化することによって燃費を向上させることによりＣＯ２排出量を削減することが求められている。このため、現在、高強度鋼板の使用による軽量化と鋼板の耐食性向上によるゲージダウンとが強く望まれている。 Demand for hot-dip Al-Si coated steel sheets with excellent corrosion resistance is growing, mainly in the field of construction materials such as roofs and walls exposed outdoors for a long time. In recent years, they have also taken advantage of their excellent heat resistance in the automotive field as well as mufflers and fuel tanks. Used in specific parts such as. In particular, in the field of automobiles, as a part of measures against global warming, it is required to reduce the CO 2 emission by improving the fuel efficiency by reducing the weight of the vehicle body. For this reason, it is now strongly desired to reduce the weight by using a high-strength steel sheet and to reduce the gauge by improving the corrosion resistance of the steel sheet.
しかしながら、溶融Ａｌ-Ｓｉ系めっき鋼板を自動車分野、特に外板パネル等の車体に用いようとした場合、化成処理性が劣るため、亜鉛めっき鋼板と比べ塗装後耐食性が劣位となるという課題があった。 However, when the hot-dip Al-Si plated steel sheet is used in the automobile field, particularly in a vehicle body such as an outer panel, there is a problem that the corrosion resistance after coating is inferior to that of the galvanized steel sheet due to poor chemical conversion property. Was.
本発明は、上記課題に鑑みてなされたものであって、その目的は、化成処理性を向上させることにより塗装後耐食性を改善可能な溶融Ａｌ-Ｓｉ系めっき鋼板及びその製造方法を提供することにある。 The present invention has been made in view of the above problems, and an object of the present invention is to provide a hot-dip Al-Si plated steel sheet capable of improving post-coating corrosion resistance by improving chemical conversion treatment properties and a method for producing the same. It is in.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板は、鋼板の表面に形成された、少なくともＡｌ，Ｓｉ，及びＦｅを含有する界面合金層と、前記界面合金層の表面に形成された、少なくともＡｌ，Ｓｉ，及びＣｕを含有するめっき層と、を有し、前記めっき層のＳｉ含有率が原子％濃度で１％以上１３％以下の範囲内にあることを特徴とする。 The hot-dip Al-Si-based plated steel sheet according to the present invention includes an interface alloy layer containing at least Al, Si, and Fe formed on the surface of the steel sheet, and at least Al, Si formed on the surface of the interface alloy layer. And a plating layer containing Si and Cu, wherein the Si content of the plating layer is in the range of 1% to 13% in atomic% concentration.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板は、上記発明において、前記めっき層のＣｕ含有率が原子％濃度で０．０５％以上３％以下の範囲内にあることを特徴とする。 The hot-dip Al-Si-based plated steel sheet according to the present invention is characterized in that, in the above invention, the Cu content of the plating layer is in the range of 0.05% to 3% in atomic% concentration.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板は、上記発明において、前記めっき層がＭｇ，Ｃａ，Ｔｉ，Ｍｎ，Ｚｎの中から選ばれる１種以上の元素をそれぞれの原子％濃度の合計で１０％以下の範囲内含有することを特徴とする。 In the hot-dip Al—Si-based plated steel sheet according to the present invention, in the above-mentioned invention, the plating layer may contain at least one element selected from Mg, Ca, Ti, Mn, and Zn in a total of 10% in atomic percent. % Or less.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板は、上記発明において、Ｘ線回折で得られるＡｌ相［１１１］の回折強度｛Ｉ（Ａｌ）｝に対するＡｌ２Ｃｕ相［２２２］の回折強度｛Ｉ（Ａｌ２Ｃｕ）｝のメインピーク強度の比率Ｙ＝Ｉ（Ａｌ２Ｃｕ）／Ｉ（Ａｌ）が０．０２以下であることを特徴とする。 The hot-dip Al—Si-based plated steel sheet according to the present invention according to the above invention, wherein the diffraction intensity ΔI of the Al 2 Cu phase [222] relative to the diffraction intensity {I (Al)} of the Al phase [111] obtained by X-ray diffraction. (Al 2 Cu)} The main peak intensity ratio Y = I (Al 2 Cu) / I (Al) is 0.02 or less.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法は、本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法であって、いずれも原子％濃度でＳｉ：１％以上１３％以下、Ｆｅ：２％以下、Ｃｕ：０．０５％以上３％以下、Ｍｇ，Ｃａ，Ｔｉ，Ｍｎ，Ｚｎの中から選ばれる１種以上の元素を合計で１０％以下の範囲内含有し、残部がＡｌ及び不可避的不純物からなり、温度が６４０℃以上６６０℃以下の範囲内にある溶融金属浴に前記鋼板を浸漬した後、６１０℃から５００℃までの平均冷却速度を１０℃／ｓ以上として急速冷却を施すステップを含むことを特徴とする。 The method for producing a hot-dip Al-Si-coated steel sheet according to the present invention is a method for manufacturing a hot-dip Al-Si-coated steel sheet according to the present invention. : 2% or less, Cu: 0.05% or more and 3% or less, containing at least one element selected from Mg, Ca, Ti, Mn, and Zn in a total amount of 10% or less, with the balance being Al After immersing the steel sheet in a molten metal bath consisting of unavoidable impurities and having a temperature in the range of 640 ° C or more and 660 ° C or less, rapid cooling at an average cooling rate of 610 ° C to 500 ° C of 10 ° C / s or more is performed. The step is performed.
本発明によれば、化成処理性を向上可能な溶融Ａｌ-Ｓｉ系めっき鋼板及びその製造方法を提供することができる。 ADVANTAGE OF THE INVENTION According to this invention, the hot-dip Al-Si type | system | group steel plate which can improve chemical conversion processability and its manufacturing method can be provided.
以下、本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板及びその製造方法について説明する。なお、以下の説明において、めっき層及びめっき浴の組成を示す各元素の含有量の単位はいずれも「原子％濃度（ａｔ％）」であり、以下、特に断らない限り単に「％」で示す。 Hereinafter, a hot-dip Al-Si-based plated steel sheet and a method for manufacturing the same according to the present invention will be described. In the following description, the unit of the content of each element indicating the composition of the plating layer and the plating bath is “atomic% concentration (at%)”, and hereinafter, simply indicated by “%” unless otherwise specified. .
〔溶融Ａｌ-Ｓｉめっき鋼板の構成〕
まず、本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板の構成について説明する。
[Configuration of hot-dip Al-Si plated steel sheet]
First, the configuration of the hot-dip Al-Si plated steel sheet according to the present invention will be described.
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板は、鋼板と、鋼板の表面に形成された、少なくともＡｌ，Ｓｉ，及びＦｅを含有する界面合金層と、界面合金層の表面に形成された、少なくともＡｌ，Ｓｉ，及びＣｕを含有するめっき層と、を有している。 The hot-dip Al-Si-based plated steel sheet according to the present invention includes: a steel sheet; an interface alloy layer containing at least Al, Si, and Fe formed on the surface of the steel sheet; and at least an interface alloy layer formed on the surface of the interface alloy layer. And a plating layer containing Al, Si, and Cu.
めっき層のＳｉ含有率は１％以上１３％以下の範囲内にある。Ｓｉ含有率が１％未満である場合、Ｆｅ−Ａｌ界面合金層の成長を抑制できない。一方、Ｓｉ含有率が１３％超である場合には、Ｆｅ−Ａｌ界面合金層の成長を抑制する効果が飽和する。 The Si content of the plating layer is in the range of 1% or more and 13% or less. If the Si content is less than 1%, the growth of the Fe—Al interface alloy layer cannot be suppressed. On the other hand, when the Si content is more than 13%, the effect of suppressing the growth of the Fe—Al interface alloy layer saturates.
めっき層のＣｕ含有率は０．０５％以上３％以下の範囲内にある。Ｃｕをめっき層に含有することで、化成処理時にめっき層の表面に電位勾配が生じ、局所的にｐＨが上昇し化成結晶の生成を促進できる。Ｃｕ含有率が０．０５％未満である場合、十分な化成処理性改善効果が得られない。一方、Ｃｕ含有率が３％超である場合には、Ａｌ２Ｃｕ相の析出量が急激に増加し、耐食性が低下する。 The Cu content of the plating layer is in the range of 0.05% or more and 3% or less. When Cu is contained in the plating layer, a potential gradient is generated on the surface of the plating layer during the chemical conversion treatment, and the pH is locally increased to promote the formation of chemical conversion crystals. If the Cu content is less than 0.05%, a sufficient effect of improving the chemical conversion treatment property cannot be obtained. On the other hand, when the Cu content is more than 3%, the precipitation amount of the Al 2 Cu phase sharply increases, and the corrosion resistance decreases.
めっき層はＭｇ，Ｃａ，Ｔｉ，Ｍｎ，Ｚｎの中から選ばれる１種以上の元素を合計で１０％以下の範囲内含有することもできる。これらの元素を含有することで、めっき層の組織が微細化し、化成処理性の改善とより優れた耐食性とを高度に両立できる。 The plating layer may contain at least one element selected from Mg, Ca, Ti, Mn, and Zn in a range of 10% or less in total. By containing these elements, the structure of the plating layer becomes finer, and it is possible to achieve a high degree of compatibility between improvement in chemical conversion treatment and more excellent corrosion resistance.
Ｘ線回折で得られるＡｌ相［１１１］の回折強度｛Ｉ（Ａｌ）｝に対するＡｌ２Ｃｕ相［２２２］の回折強度｛Ｉ（Ａｌ２Ｃｕ）｝のメインピーク強度の比率Ｙ＝Ｉ（Ａｌ２Ｃｕ）／Ｉ（Ａｌ）は０．０２以下である。比率Ｙが０．０２超であることは、Ａｌ２Ｃｕ相がめっき層の表層に過剰に析出していることを示し、化成処理性に優れた合金組成であっても耐食性に劣った皮膜となる可能性がある。比率Ｙと製造パラメータの相関は明らかでないが、浴中Ｃｕ量の増大及びめっき後の冷却速度の低下により増大する傾向にある。 Ratio of main peak intensity of diffraction intensity {I (Al 2 Cu)} of Al 2 Cu phase [222] to diffraction intensity {I (Al)} of Al phase [111] obtained by X-ray diffraction Y = I (Al) 2 Cu) / I (Al) is 0.02 or less. When the ratio Y is more than 0.02, it indicates that the Al 2 Cu phase is excessively precipitated on the surface layer of the plating layer, and a film having poor corrosion resistance even with an alloy composition having excellent chemical conversion property. Could be. Although the correlation between the ratio Y and the production parameter is not clear, it tends to increase due to an increase in the amount of Cu in the bath and a decrease in the cooling rate after plating.
〔溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法〕
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法は、本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板を製造する際、Ｓｉ：１％以上１３％以下、Ｆｅ：２％以下、Ｃｕ：０．０５％以上３％以下、Ｍｇ，Ｃａ，Ｔｉ，Ｍｎ，Ｚｎの中から選ばれる１種以上の元素を合計で１０％以下の範囲内含有し、残部がＡｌ及び不可避的不純物からなり、温度が６４０℃以上６６０℃以下の範囲内にある溶融金属浴に鋼板を浸漬した後、６１０℃から５００℃までの平均冷却速度を１０℃／ｓ以上として急速冷却を施すステップを含む。
[Method of manufacturing hot-dip Al-Si-based plated steel sheet]
The method for producing a hot-dip Al-Si-based coated steel sheet according to the present invention is characterized in that when manufacturing the hot-dip Al-Si-based coated steel sheet according to the present invention, Si: 1% or more and 13% or less, Fe: 2% or less, Cu: 0 0.05% or more and 3% or less, containing at least one element selected from Mg, Ca, Ti, Mn and Zn in a total amount of 10% or less, with the balance being Al and unavoidable impurities. After the steel sheet is immersed in a molten metal bath having a temperature in the range of 640 ° C. or more and 660 ° C. or less, rapid cooling is performed at an average cooling rate from 610 ° C. to 500 ° C. of 10 ° C./s or more.
次に、本発明の実施例について説明する。 Next, examples of the present invention will be described.
（サンプル１〜４３）
サンプルとなる全ての溶融Ａｌ-Ｓｉ系めっき鋼板について、常法で製造した板厚０．８ｍｍの冷延鋼板を下地鋼板として用い、溶融めっき設備において、めっき浴の浴温を６６０℃、浸入温度を６８０℃、ラインスピード６０ｍｐｍ、浸漬時間２秒で、めっき浴の組成を種々の条件に変化させ、各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板を製造した。なお、めっき浴の組成は、サンプルの製造に用いためっき浴から約２ｇを採取し、化学分析によって確認した。各サンプルのめっき浴の組成を以下の表１に示す。また、めっき浴浸漬後の窒素ガスによる冷却の６１０℃から５００℃までの冷却速度を以下の表１に示す。さらに、界面合金層及びめっき層の組成については、各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板から任意の３断面を剪断加工により切り出し、カーボン樹脂に埋め込んだ上でＳＥＭ−ＥＤＸ観察を行い、界面合金層及びめっき層のうち、任意の５点でＥＤＸにより測定した半定量分析値の平均値を用いた。各サンプルの界面合金層及びめっき層の組成を以下の表１に示す。
(Samples 1 to 43)
For all the hot-dip Al-Si plated steel sheets to be used as samples, a cold-rolled steel sheet with a thickness of 0.8 mm manufactured by a conventional method is used as a base steel sheet. At 680 ° C., a line speed of 60 mpm, and an immersion time of 2 seconds, the composition of the plating bath was changed to various conditions to produce a hot-dip Al-Si-based plated steel sheet of each sample. The composition of the plating bath was confirmed by collecting about 2 g from the plating bath used for producing the sample and performing chemical analysis. The composition of the plating bath for each sample is shown in Table 1 below. Table 1 below shows the cooling rate from 610 ° C. to 500 ° C. of cooling by nitrogen gas after immersion in the plating bath. Furthermore, regarding the composition of the interfacial alloy layer and the plating layer, three arbitrary cross sections were cut out from the molten Al-Si-based plated steel sheet of each sample by shearing, embedded in carbon resin, and observed by SEM-EDX. The average value of the semi-quantitative analysis values measured by EDX at five arbitrary points among the layer and the plating layer was used. Table 1 shows the compositions of the interface alloy layer and the plating layer of each sample.
各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板の比率Ｙ、化成処理性、裸耐食性、及び塗装後耐食性を以下に示す方法により評価した。 The ratio Y of the hot-dip Al-Si-plated steel sheet of each sample, the chemical conversion property, the bare corrosion resistance, and the corrosion resistance after painting were evaluated by the following methods.
１．比率Ｙ
Ａｌ相［１１１］の回折強度｛Ｉ（Ａｌ）｝に対するＡｌ２Ｃｕ相［２２２］の回折強度｛Ｉ（Ａｌ２Ｃｕ）｝のメインピーク強度の比率Ｙ＝Ｉ（Ａｌ２Ｃｕ）／Ｉ（Ａｌ）は、Ｃｕ−Ｋα線を使用したＸ線回折装置により回折図形を測定して判定した。
1. Ratio Y
The ratio of the diffraction intensity {I (Al)} of the Al phase [111] to the main peak intensity of the diffraction intensity {I (Al 2 Cu)} of the Al 2 Cu phase [222] Y = I (Al 2 Cu) / I ( Al) was determined by measuring a diffraction pattern with an X-ray diffractometer using Cu-Kα rays.
２．化成処理性
市販の化成処理薬剤（日本パーカライジング株式会社製パルボンドＳＸ−３５）を用いて、浴温：３５℃、フリーフッ素濃度：２００質量ｐｐｍ、処理時間：１２０秒の条件で鋼板の化成処理を行った後、そのめっき鋼板の表面を走査型電子顕微鏡にて１０００倍で１０視野観察した。結晶の形態については、面積率９８％以上の均一な化成結晶が１０視野全てにおいて生成しているものを優（◎）、面積率９８％未満の視野が１視野認められるものを良（○）、面積率９８％未満の視野が２視野認められるものを可（△）とし、面積率９８％未満の視野が３視野以上認められるものを不可（×）として評価した。なお、ここでいう隙間とは、均一な化成結晶が生成していない箇所のことを指し、反射電子像を２値化することにより空隙の面積率を算出した。また、結晶の付着量は、化成処理試験後の試料３点を２０ｇ／Ｌの重クロム酸アンモニウム水溶液に１５分間浸漬し、浸漬前後の重量差から試験片面積当たりの値として算出した。３点すべてにおいて結晶の付着量が２．０ｇ／ｍ２以上のものを優(◎)、１．８ｇ／ｍ２以上２．０ｇ／ｍ２未満のものを良(○)、１．５ｇ／ｍ２以上１．８ｇ／ｍ２未満のものを可(△)、１．５ｇ／ｍ２未満のものが１点でも認められるものを不可(×)として評価した。
2. Chemical conversion treatment Using a commercially available chemical conversion chemical (PALBOND SX-35 manufactured by Nippon Parkerizing Co., Ltd.), the steel plate was subjected to chemical conversion under the conditions of bath temperature: 35 ° C, free fluorine concentration: 200 mass ppm, and treatment time: 120 seconds. After performing, the surface of the plated steel sheet was observed with a scanning electron microscope at a magnification of 1000 at 10 fields of view. Regarding the morphology of the crystals, excellent (◎) means that a uniform chemical conversion crystal having an area ratio of 98% or more is generated in all 10 visual fields, and good (○) means that one visual field having an area ratio of less than 98% is recognized. The case where two visual fields having an area ratio of less than 98% were recognized was evaluated as acceptable (△), and the case where three or more visual fields having an area ratio of less than 98% were observed was evaluated as unacceptable (x). Here, the gap refers to a place where a uniform chemical conversion crystal is not generated, and the area ratio of the gap is calculated by binarizing the reflected electron image. Further, the amount of attached crystals was calculated by immersing three samples after the chemical conversion test in a 20 g / L ammonium bichromate aqueous solution for 15 minutes, and calculating the value per test piece area from the weight difference before and after immersion. At all three points, those having a crystal adhesion amount of 2.0 g / m 2 or more are excellent (◎), those having 1.8 g / m 2 or more and less than 2.0 g / m 2 are good ((), and 1.5 g / m 2. m 2 or more 1.8 g / m 2 less soluble ones (△), of less than 1.5 g / m 2 was evaluated as bad (×) those observed even at one point.
３．裸耐食性
各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板について、ＪＩＳ Ｚ２３７１−２０００に準拠した塩水噴霧試験を行った。各サンプルの赤錆が発生するまでの時間を測定し、以下の基準により裸耐食性を評価した。評価結果を以下の表１に示す。
3. Bare corrosion resistance A salt spray test based on JIS Z2371-2000 was performed on the hot-dip Al-Si-based plated steel sheet of each sample. The time until red rust of each sample was measured, and the bare corrosion resistance was evaluated according to the following criteria. The evaluation results are shown in Table 1 below.
◎：赤錆発生時間≧６００時間
○：３００時間≦赤錆発生時間＜６００時間
△：１５０時間≦赤錆発生時間＜３００時間
×：赤錆発生時間＜１５０時間
：: Red rust occurrence time ≧ 600 hours ○: 300 hours ≦ Red rust occurrence time <600 hours Δ: 150 hours ≦ Red rust occurrence time <300 hours ×: Red rust occurrence time <150 hours
４．塗装後耐食性
各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板について、それぞれ７０ｍｍ×８０ｍｍのサイズに剪断後、自動車外板用塗装処理と同様に、化成処理としてリン酸亜鉛処理を行った後、電着塗装を施した。ここで、リン酸亜鉛処理及び電着塗装は、以下の条件で行った。
4. Corrosion resistance after painting The molten Al-Si plated steel sheet of each sample was sheared to a size of 70 mm x 80 mm, and subjected to zinc phosphate treatment as a chemical conversion treatment in the same manner as coating treatment for automobile outer panels, followed by electrodeposition coating Was given. Here, the zinc phosphate treatment and the electrodeposition coating were performed under the following conditions.
リン酸亜鉛処理：市販の化成処理薬剤（日本パーカライジング株式会社製パルボンドＳＸ−３５）を用いて、浴温：３５℃、フリーフッ素濃度：２００質量ｐｐｍ、処理時間：１２０秒の条件で溶融Ａｌ-Ｓｉ系めっき鋼板の化成処理を行った。 Zinc phosphate treatment: Using a commercially available chemical conversion treatment agent (Palbond SX-35 manufactured by Nippon Parkerizing Co., Ltd.), bath Al temperature: 35 ° C., free fluorine concentration: 200 mass ppm, treatment time: 120 sec. A chemical conversion treatment was performed on the Si-based plated steel sheet.
電着塗装：関西ペイント社製の電着塗料：ＧＴ−１００を用いて、膜厚が１５μｍとなるように電圧を調整して電着塗装を施した。 Electrodeposition coating: Electrodeposition coating was performed by adjusting the voltage so that the film thickness became 15 μm using an electrodeposition coating material manufactured by Kansai Paint Co., Ltd .: GT-100.
化成処理及び電着塗装後、評価面の端部７．５及び非評価面（背面）をテープでシール処理を行った後、評価面の中央にカッターナイフで溶融Ａｌ-Ｓｉ系めっき鋼板の地鉄に到達する深さまで、長さ６０ｍｍ、中心角６０°のクロスカット傷を加えたものを、塗装後耐食性の評価用サンプルとして用いた。 After the chemical conversion treatment and the electrodeposition coating, the edge 7.5 of the evaluation surface and the non-evaluation surface (back surface) are sealed with a tape, and the center of the evaluation surface is ground with a cutter knife using a molten Al-Si-based plated steel sheet. A cross-cut flaw having a length of 60 mm and a central angle of 60 ° until the depth reaching the iron was used as a sample for evaluating corrosion resistance after painting.
上記評価用サンプルを用いて、ＳＡＥ Ｊ２３３４に規定されたサイクルで腐食促進試験を実施した。腐食促進試験を湿潤状態からスタートし、６０サイクル後まで行った後、傷部からの塗膜膨れが最大である部分の塗膜膨れ幅（最大塗膜膨れ幅：傷部を中央にした片側の最大塗膜膨れ幅）を測定し、塗装後耐食性を以下の基準で評価した。評価結果を以下の表１に示す。 Using the sample for evaluation, a corrosion acceleration test was performed in a cycle specified in SAE J2334. After the corrosion promotion test was started from the wet state and was performed up to 60 cycles, the coating swelling width of the portion where the coating swelling from the scratch was the largest (maximum coating swelling width: one side with the scratch at the center) The maximum coating blister width was measured, and the corrosion resistance after coating was evaluated according to the following criteria. The evaluation results are shown in Table 1 below.
◎：最大塗膜膨れ幅≦２．０ｍｍ
○：２．０ｍｍ＜最大塗膜膨れ幅≦３．０ｍｍ
△：３．０ｍｍ＜最大塗膜膨れ幅≦４．０ｍｍ
×：最大塗膜膨れ幅＞４．０ｍｍ
◎: maximum coating blister width ≦ 2.0 mm
：: 2.0 mm <maximum coating blister width ≦ 3.0 mm
Δ: 3.0 mm <maximum swollen film width ≦ 4.0 mm
×: Maximum coating swollen width> 4.0 mm
以下の表１に示すように、比較例では化成処理性が不足しているか、あるいはＡｌ２Ｃｕ相が過剰となりいずれも塗装後耐食性に不足があった。これに対して、本発明例は化成処理性及び塗装後耐食性共に優れていた。これにより、本発明によれば、溶融Ａｌ−Ｓｉ系めっき鋼板の化成処理性を向上させることにより塗装後耐食性を改善できることが確認された。 As shown in Table 1 below, in the comparative examples, the chemical conversion treatment property was insufficient, or the Al 2 Cu phase was excessive and the corrosion resistance after coating was insufficient in all cases. On the other hand, the examples of the present invention were excellent in both chemical conversion property and corrosion resistance after painting. Thereby, according to the present invention, it was confirmed that the corrosion resistance after coating can be improved by improving the chemical conversion treatment property of the hot-dip Al-Si-based plated steel sheet.
〔溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法〕
本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板の製造方法は、本発明に係る溶融Ａｌ-Ｓｉ系めっき鋼板を製造する際、Ｓｉ：１％以上１３％以下、Ｆｅ：２％以下、Ｃｕ：０．０５％以上３％以下、Ｍｇ，Ｃａ，Ｔｉ，Ｍｎ，Ｚｎの中から選ばれる１種以上の元素を合計で１０％以下の範囲内含有し、残部がＡｌ及び不可避的不純物からなり、温度が６４０℃以上６６０℃以下の範囲内にある溶融金属浴に鋼板を浸漬した後、鋼板を取り出し、６１０℃から５００℃までの平均冷却速度を１０℃／ｓ以上として急速冷却を施すステップを含む。
[Method of manufacturing hot-dip Al-Si-based plated steel sheet]
The method for producing a hot-dip Al-Si-based coated steel sheet according to the present invention is characterized in that when manufacturing the hot-dip Al-Si-based coated steel sheet according to the present invention, Si: 1% or more and 13% or less, Fe: 2% or less, Cu: 0 0.05% or more and 3% or less, containing at least one element selected from Mg, Ca, Ti, Mn and Zn in a total amount of 10% or less, with the balance being Al and unavoidable impurities. Immersing the steel sheet in a molten metal bath having a temperature in the range of 640 ° C. or more and 660 ° C. or less, removing the steel sheet, and performing rapid cooling at an average cooling rate of 610 ° C. to 500 ° C. of 10 ° C./s or more. .
（サンプル１〜４３）
サンプルとなる全ての溶融Ａｌ-Ｓｉ系めっき鋼板について、常法で製造した板厚０．８ｍｍの冷延鋼板を下地鋼板として用い、溶融めっき設備において、めっき浴の浴温を６６０℃、鋼板の浸入温度を６８０℃、ラインスピード６０ｍｐｍ、浸漬時間２秒で、めっき浴の組成を種々の条件に変化させ、各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板を製造した。なお、めっき浴の組成は、サンプルの製造に用いためっき浴から約２ｇを採取し、化学分析によって確認した。各サンプルのめっき浴の組成を以下の表１に示す。また、めっき浴浸漬後の窒素ガスによる冷却の６１０℃から５００℃までの冷却速度を以下の表１に示す。さらに、界面合金層及びめっき層の組成については、各サンプルの溶融Ａｌ-Ｓｉ系めっき鋼板から任意の３断面を剪断加工により切り出し、カーボン樹脂に埋め込んだ上でＳＥＭ−ＥＤＸ観察を行い、界面合金層及びめっき層のうち、任意の５点でＥＤＸにより測定した半定量分析値の平均値を用いた。各サンプルの界面合金層及びめっき層の組成を以下の表１に示す。
(Samples 1 to 43)
For all the hot-dip Al-Si plated steel sheets to be used as samples, a cold-rolled steel sheet with a thickness of 0.8 mm manufactured by a conventional method is used as a base steel sheet. The infiltration temperature was 680 ° C., the line speed was 60 mpm, and the immersion time was 2 seconds. The composition of the plating bath was changed to various conditions, and molten Al—Si-based plated steel sheets of each sample were manufactured. The composition of the plating bath was confirmed by collecting about 2 g of the plating bath used for producing the sample and performing chemical analysis. The composition of the plating bath for each sample is shown in Table 1 below. Table 1 below shows the cooling rate from 610 ° C. to 500 ° C. of cooling by nitrogen gas after plating bath immersion. Furthermore, regarding the composition of the interfacial alloy layer and the plating layer, three arbitrary cross sections were cut out from the molten Al-Si-based plated steel sheet of each sample by shearing, embedded in carbon resin, and observed by SEM-EDX. The average value of the semi-quantitative analysis values measured by EDX at five arbitrary points among the layer and the plating layer was used. Table 1 shows the compositions of the interface alloy layer and the plating layer of each sample.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018127468A JP6922857B2 (en) | 2018-07-04 | 2018-07-04 | Fused Al-Si plated steel sheet and its manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018127468A JP6922857B2 (en) | 2018-07-04 | 2018-07-04 | Fused Al-Si plated steel sheet and its manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2020007585A true JP2020007585A (en) | 2020-01-16 |
| JP6922857B2 JP6922857B2 (en) | 2021-08-18 |
Family
ID=69150844
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018127468A Active JP6922857B2 (en) | 2018-07-04 | 2018-07-04 | Fused Al-Si plated steel sheet and its manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6922857B2 (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0364438A (en) * | 1989-07-31 | 1991-03-19 | Kawasaki Steel Corp | Manufacture of hot dip aluminized chromium-containing steel sheet |
| JPH04107217A (en) * | 1990-08-24 | 1992-04-08 | Kobe Steel Ltd | Production of hot rolled and surface treated steel sheet having high tensile strength |
| JPH06207262A (en) * | 1993-01-06 | 1994-07-26 | Sky Alum Co Ltd | Far infrared ray radiation member and manufacture thereof |
| JP2004143506A (en) * | 2002-10-23 | 2004-05-20 | Nippon Steel Corp | Hot dip plated steel sheet having excellent appearance quality, and production method for the hot dip plated steel sheet |
| JP2007107050A (en) * | 2005-10-13 | 2007-04-26 | Nippon Steel Corp | HOT DIP Al BASED PLATED STEEL SHEET HAVING EXCELLENT WORKABILITY AND METHOD FOR PRODUCING THE SAME |
-
2018
- 2018-07-04 JP JP2018127468A patent/JP6922857B2/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0364438A (en) * | 1989-07-31 | 1991-03-19 | Kawasaki Steel Corp | Manufacture of hot dip aluminized chromium-containing steel sheet |
| JPH04107217A (en) * | 1990-08-24 | 1992-04-08 | Kobe Steel Ltd | Production of hot rolled and surface treated steel sheet having high tensile strength |
| JPH06207262A (en) * | 1993-01-06 | 1994-07-26 | Sky Alum Co Ltd | Far infrared ray radiation member and manufacture thereof |
| JP2004143506A (en) * | 2002-10-23 | 2004-05-20 | Nippon Steel Corp | Hot dip plated steel sheet having excellent appearance quality, and production method for the hot dip plated steel sheet |
| JP2007107050A (en) * | 2005-10-13 | 2007-04-26 | Nippon Steel Corp | HOT DIP Al BASED PLATED STEEL SHEET HAVING EXCELLENT WORKABILITY AND METHOD FOR PRODUCING THE SAME |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6922857B2 (en) | 2021-08-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107250418B (en) | Hot-dip Al-Zn-Mg-Si-coated steel sheet and method for producing same | |
| JP6368730B2 (en) | Molten Al-Zn-Mg-Si plated steel sheet and method for producing the same | |
| EP2578719B1 (en) | Hot-dip aluminum alloy plated steel having excellent shear cut edge corrosion resistance and processed part corrosion resistance, and method of manufacturing the same | |
| JP6645273B2 (en) | Hot-dip Al-Zn-Mg-Si plated steel sheet and method for producing the same | |
| US10822685B2 (en) | Hot-dip Al alloy coated steel sheet and method of producing same | |
| CN110392744A (en) | Coated steel sheet | |
| JP7401827B2 (en) | Hot-dip Zn-based plated steel sheet | |
| JP5991379B2 (en) | Al-Zn plated steel sheet | |
| JP2013248645A (en) | Hot press-formed member having high strength and high corrosion resistance | |
| WO2020213680A1 (en) | Plated steel material | |
| JP4461866B2 (en) | Hot-dip Zn-Al alloy-plated steel sheet excellent in corrosion resistance and bending workability and manufacturing method thereof | |
| JP6922857B2 (en) | Fused Al-Si plated steel sheet and its manufacturing method | |
| JP6922858B2 (en) | Fused Al-Zn-based plated steel sheet and its manufacturing method | |
| JPS63243295A (en) | Rust preventive steel sheet having superior corrosion resistance | |
| JP2004277839A (en) | Zinc based metal-coated steel | |
| TWI690604B (en) | HOT DIP Sn-Zn TYPE ALLOY PLATED STEEL SHEET, AND MANUFACTURING METHOD THEREFOR | |
| JP2018016887A (en) | Production method of hot press molding member | |
| JP4537894B2 (en) | Hot Sn-Zn plated steel sheet with good corrosion resistance and weldability | |
| JP2636589B2 (en) | Zinc-nickel-chromium alloy electroplated steel sheet with excellent corrosion resistance, plating adhesion and chemical conversion treatment | |
| JPH0611919B2 (en) | Cold rolled steel sheet with excellent corrosion resistance after painting | |
| JP2020122204A (en) | Al-BASED PLATED SHEET STEEL AND MANUFACTURING METHOD THEREOF | |
| Britton et al. | THE EFFECT OF ANTIMONY ADDITIONS ON THE MICROSTRUCTURE AND PERFORMANCE OF AUTOMOTIVE ZN-MG-AL STEEL COATINGS | |
| JP2002212753A (en) | Aluminum alloy material having excellent phosphate treatability and production method therefor | |
| JPH06235085A (en) | Zn-cr base surface-back different plating rust preventive steel sheet excellent in corrosion resistance | |
| JP2001303290A (en) | Al-Mg-Si-Cu BASED ALLOY PLATE EXCELLENT IN PHOSPHATE PROCESSABILITY AND AFTER COATING CORROSION RESISTANCE AND ITS MANUFACTURING METHOD |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190227 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20200220 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20201120 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20201208 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20210113 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20210525 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20210611 |
|
| 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: 20210629 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20210712 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6922857 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |