JPS63192890A - Surface treated steel sheet having superior corrosion resistance and suitability to coating by electrodeposition - Google Patents
Surface treated steel sheet having superior corrosion resistance and suitability to coating by electrodepositionInfo
- Publication number
- JPS63192890A JPS63192890A JP2520787A JP2520787A JPS63192890A JP S63192890 A JPS63192890 A JP S63192890A JP 2520787 A JP2520787 A JP 2520787A JP 2520787 A JP2520787 A JP 2520787A JP S63192890 A JPS63192890 A JP S63192890A
- Authority
- JP
- Japan
- Prior art keywords
- steel sheet
- corrosion resistance
- coating
- electrodeposition
- suitability
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 26
- 238000005260 corrosion Methods 0.000 title claims abstract description 26
- 230000007797 corrosion Effects 0.000 title claims abstract description 26
- 239000010959 steel Substances 0.000 title claims abstract description 26
- 239000011248 coating agent Substances 0.000 title claims abstract description 17
- 238000000576 coating method Methods 0.000 title claims abstract description 17
- 238000004070 electrodeposition Methods 0.000 title claims abstract description 12
- 238000007747 plating Methods 0.000 claims abstract description 17
- 229910000640 Fe alloy Inorganic materials 0.000 claims abstract description 12
- 238000009713 electroplating Methods 0.000 abstract description 5
- 229910019142 PO4 Inorganic materials 0.000 description 12
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 12
- 239000010452 phosphate Substances 0.000 description 12
- 239000010410 layer Substances 0.000 description 10
- 239000013078 crystal Substances 0.000 description 9
- 229910052827 phosphophyllite Inorganic materials 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 5
- 239000007921 spray Substances 0.000 description 4
- 239000011701 zinc Substances 0.000 description 4
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000003973 paint Substances 0.000 description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000004580 weight loss Effects 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 240000008564 Boehmeria nivea Species 0.000 description 1
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 229910000645 Hg alloy Inorganic materials 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 125000002091 cationic group Chemical group 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000003017 phosphorus Chemical class 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- YWYZEGXAUVWDED-UHFFFAOYSA-N triammonium citrate Chemical compound [NH4+].[NH4+].[NH4+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O YWYZEGXAUVWDED-UHFFFAOYSA-N 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 1
- 229910000368 zinc sulfate Inorganic materials 0.000 description 1
- 239000011686 zinc sulphate Substances 0.000 description 1
- 235000009529 zinc sulphate Nutrition 0.000 description 1
Landscapes
- Electroplating Methods And Accessories (AREA)
- Chemical Treatment Of Metals (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は裸耐食性に優れ、かつ緻密なリン酸塩結晶皮膜
の形成により電着ｍｉｉ性が優れたＺｎ−Ｆｅ系合金電
気めっき鋼板に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a Zn-Fe alloy electroplated steel sheet that has excellent bare corrosion resistance and excellent electrodepositability due to the formation of a dense phosphate crystal film.
（従米扶術）
Ｚｎ−Ｆｅｉｋ舎会め−）き鋼板は純亜鉛めっき鋼板よ
りめっき層の亜鉛腐食溶解速度が遅く、耐食性に優れて
いるので、従来上り高度の耐食性を必要とする自動車車
体などに使用されている。このめっき鋼板は電気めっき
法皇雌は溶融めっき法によりｗ造されでい７１ ｆｊｔ
−め。鋒層頗虚けＦｅ含有率が重量％で１θ〜３０％の
ものである。これはＦｅ含有率が１０％未満であると、
Ｆｅによる亜鉛腐食溶解速度抑制効果が不十分なため、
塗装しても塗膜を透過侵入して（るＨ、０やＣ１イオン
などによりＺｎＯや’１ｎ（Ｏｉｌ）ｔなどの腐食生成
物を形成して、短期間に！１１１７クレ（ブリスター）
を発生させ、塗ＩＮ＠離が生じやすくなり、逆に３０％
を越えると鋼板の裸耐食性が劣り、赤錆が発生しやすく
なると同時にめっき層の加工性が者しく悪くなるためで
ある。Zn-Feikshakai) coated steel sheets have a slower zinc corrosion dissolution rate in the plating layer than pure galvanized steel sheets, and have excellent corrosion resistance, so they can be used in automobile bodies, etc., which conventionally require a high degree of corrosion resistance. used in This plated steel sheet can be manufactured by electroplating and hot-dip plating.71 fjt
-Me. The Fe content in the front layer is 1θ to 30% by weight. This means that if the Fe content is less than 10%,
Because the effect of Fe on inhibiting zinc corrosion dissolution rate is insufficient,
Even if it is painted, it will penetrate through the paint film and form corrosion products such as ZnO and '1n(Oil)t due to H, 0 and C1 ions, resulting in blister formation in a short period of time.
This causes coating in@ separation to occur easily, and conversely, it increases by 30%
This is because, if it exceeds this value, the bare corrosion resistance of the steel sheet will be poor, red rust will easily occur, and at the same time, the workability of the plating layer will deteriorate significantly.
（発明が解決しようとする間ｊｌｆｌ、１しかしながら
めっき層のＦｅ含有率が上記のような組成でもめっき鋼
板の裸耐食性はまだ不十分で未塗装で使用する場合に問
題があった。(While the invention was trying to solve this problem, there was a problem when the plated steel sheet was used without coating because the bare corrosion resistance of the plated steel sheet was still insufficient even if the Fe content of the plated layer was as above.)
またＺｎ−Ｆｅ系合金めっき鋼板を自動車車体に使用す
る場合、リン酸塩処理を施して電着塗装するが、リン酸
塩処理で形成される皮膜は一般に結晶が針状で粗大なホ
バイト［１Ｉｏｐｉｔｅ Ｚｎ１（ＰＯ＜）ｔ ＊４
）１．０１系のものより結晶の緻密なホスホフイライ）
［Ｐｈｏｓｐｈｏｐｈｉｌｉｔｅ ＺｎＪｅ（Ｐａ
ｎ）ｘ ６４ＨｔＯＪ系のものの方が！Ｉｋ膜密着性に
優れでいる。Furthermore, when Zn-Fe alloy plated steel sheets are used for automobile bodies, they are subjected to phosphate treatment and then electrodeposited, but the film formed by phosphate treatment is generally composed of coarse hovite [1Iopite] with needle-like crystals. Zn1(PO<)t *4
) Phosphophile with denser crystals than those of the 1.01 series)
[Phosphophilite ZnJe(Pa
n) x 64HtOJ type is better! Excellent Ik film adhesion.
しかし従来の＃ｌ板はＦｅ含有率が低いため、リン酸塩
皮膜はホスホフィライト結晶のものにならず、ホバイト
結晶のものが主であった。このため電着塗装時の耐クレ
ーター性が劣り、またａ装しても塗膜二次密着性や耐食
性などが劣るという欠点があった。However, since the conventional #l plate has a low Fe content, the phosphate film was not made of phosphophyllite crystals, but was mainly made of hovite crystals. For this reason, there were drawbacks such as poor crater resistance during electrodeposition coating, and poor secondary coating adhesion and corrosion resistance even when coated with A.
リン酸塩皮膜の結晶を主にホスホフィライトのものにす
るには、Ｆｅ含有率を高めればよいのであるが、Ｆｅ含
有率を高めると上記のように種々の問題が生じる。この
ためめっき屑表屓にさらにＦｅＰ。In order to make the crystals of the phosphate film mainly composed of phosphophyllite, it is sufficient to increase the Fe content, but increasing the Fe content causes various problems as described above. For this reason, FeP is added to the surface of the plating scrap.
の電気めっきを施して表層のＦｅ含有率を高める方法が
提案されている。しかしこの方法はめっき工程が２工程
になるので、製造コストの上昇を招いてしまう。A method of increasing the Fe content of the surface layer by electroplating has been proposed. However, since this method requires two plating steps, the manufacturing cost increases.
以上のようなことがらＺｎ−Ｆｅ系合金電気めっき鋼板
の場合、加工性が従来と同等以上で、１工程でめっ８′
ｃき、しがも裸耐食性が向上し、かつリン酸塩処理した
場合の結晶がホスホフィライト主成分になりで電着塗装
性の優れたものにする必要があった。As mentioned above, in the case of Zn-Fe alloy electroplated steel sheets, the workability is equal to or better than conventional ones, and it is possible to plate 8' in one process.
However, it was necessary to improve the bare corrosion resistance, and when treated with a phosphate, the crystals become phosphophyllite as a main component, so it was necessary to have excellent electrodeposition coating properties.
（間Ｉｇ息を解決するための手段）
本発明者らは上記条件を充たすＺｎ−ＦｅＰ、合金めっ
き鋼板を開発すべく、種々検討した結果、めっき層にＭ
、を微！添加すると裸耐食性が向上し、かつリン酸塩結
晶もＪｌ密なホスホフィライトが主成分のものになり、
裸耐食性、電着塗装性に優れた鋼板が得られることを見
出し、本発明を完成したのである。すなわち本発明は重
量％でＦｅ含有率が１０〜３０％であるＺｎ−Ｆｅ系合
金Ｔｉ気めっき＃ｇ板のめっき層にＭｇを０．０５〜２
％添加することにより裸耐食性、１を着塗装性を向上さ
せたのである。(Means for solving the problem of Ig breath) The present inventors conducted various studies in order to develop a Zn-FeP and alloy-plated steel sheet that satisfies the above conditions.
, fine! When added, bare corrosion resistance is improved, and the phosphate crystals are mainly composed of Jl-dense phosphophyllite.
They discovered that a steel plate with excellent bare corrosion resistance and electrodeposition coating properties could be obtained, and completed the present invention. That is, in the present invention, 0.05 to 2% Mg is added to the plating layer of a Zn-Fe alloy Ti plating #g plate having an Fe content of 10 to 30% by weight.
By adding 1%, bare corrosion resistance and 1% paintability were improved.
本発明でめっき層のＦｅ含有率を１０〜３０％にしたの
は、従来のＺｎ−Ｆｅ系合金めっき鋼板の場合と同理由
であるが、Ｈ，添加量を０．０５〜２％にしたのは、０
．０５％未満であると裸耐食性改善効果が小さく、２％
を越える量含有させるとリン＃塩処理性が劣化し、加工
性も悪化するからである。In the present invention, the Fe content in the plating layer is set to 10 to 30% for the same reason as in the case of conventional Zn-Fe alloy plated steel sheets, but the amount of H added is set to 0.05 to 2%. is 0
．． If it is less than 0.05%, the effect of improving bare corrosion resistance is small;
This is because if it is contained in an amount exceeding this amount, the phosphorus salt treatment properties will deteriorate and the processability will also deteriorate.
鋼板にＮ、を添加したＺｎ−Ｆｅ系合金を電気めっきす
るのには、例えばＺｎ”濃度１０〜５０９／ｅ。For electroplating a Zn-Fe alloy containing N on a steel plate, the Zn'' concentration is, for example, 10 to 509/e.
ＦｅＮ濃度２０−７０９／ｅ、Ｍ ｇ ％濃度５〜２０
９／ｇ％ｐＨ６以下のめっき浴で電流密度１０〜２００
＾／ｄａ”、好ましくは５０＾／ｄｍ’以上、鋼板とめ
っ！液との相対流速０．５ｍ／ｓｅｃ以上で行えば得ら
れる。FeN concentration 20-709/e, Mg% concentration 5-20
9/g% Current density 10-200 in plating bath with pH 6 or less
^/dm', preferably 50^/dm' or more, and the relative flow rate between the steel plate and the liquid is 0.5 m/sec or more.
（作用）
添付図面はＺｎ−２０％Ｆｅ合金電気めっト鋼板のめっ
き層にＭ「を添加した場合のＮＨ添加量と塩水噴霧試験
（４８時間）による腐食減量を示したものであるが、Ｎ
、を添加すると裸耐食性が向上する。(Function) The attached drawing shows the amount of NH added and the corrosion loss in a salt spray test (48 hours) when M is added to the plating layer of a Zn-20% Fe alloy electroplated steel sheet. N
, improves bare corrosion resistance.
（実施例）
冷［、ＩＩＩＮの表面を常法により清浄化した後、下記
のめりｂ浴、めっ終条件でＺｎ−Ｆｅ系またはＺｎ −
Ｆｅ−Ｈｇ系合金を電気めっきした。なおめっき層のＦ
ｅお上りＨ８量はそれぞれＦｅ５０＜ ・７ｔｌｚＯお
よびＭ、０粉末の添加量により１Ｍ整した。(Example) After cleaning the surface of cold [, IIIN by a conventional method, Zn-Fe-based or Zn -
A Fe-Hg alloy was electroplated. Furthermore, the F of the plating layer
eThe amount of H8 was adjusted to 1M by adding the amount of Fe50<・7tlzO and M,0 powder, respectively.
浴組成 ＺｎＳＯ４・７Ｌ０ １２（１
９／ ｅＦｅＳＯ，−７８，０２００−２８０９／ｅＨ
ｇＯ５＝５０９／ｅ
ＮａｚＳＯｎ ８０９／ｅ酒石
ＩＩ Ｏ，５９ｉＡ 苧
リ −八 Ｃａ／）
ポリビニルアルコール ０．５９／ｅｐｔ＋
５
浴温 ５０℃
電流密度 ４０〜１５０＾／ｄ−２
めっき後は一部のものを裸耐食性試験し、他のものには
リン酸塩処理、電着塗装を行い、リン酸塩処理性および
電着塗装性を調査した。ｆＩＳ１表にこの結果を示す、
なおこれらの調査は次のような試験により行った。Bath composition ZnSO4・7L0 12(1
9/eFeSO,-78,0200-2809/eH
gO5=509/e NazSON 809/e Tarase II O,59iA Ramie
Li-8 Ca/) Polyvinyl alcohol 0.59/ept+
5 Bath temperature: 50°C Current density: 40-150^/d-2 After plating, some parts were subjected to a bare corrosion resistance test, and others were subjected to phosphate treatment and electrodeposition coating, and phosphate treatment properties and Electrodeposition coating properties were investigated. This result is shown in fIS1 table,
These investigations were conducted using the following tests.
（１）裸耐食性試験
塩水噴霧試験を２４時間行って赤錆発生面積を求めると
ともに、試験片を５％クエン酸アンモニウムに浸漬して
赤錆を溶解させ、試験前後の腐食減量を求めた。(1) Bare Corrosion Resistance Test A salt spray test was conducted for 24 hours to determine the area where red rust occurred, and the test piece was immersed in 5% ammonium citrate to dissolve the red rust, and the corrosion weight loss before and after the test was determined.
（２）リン酸塩処理性試験
日本パーカーライノング（株）製のリン酸塩処理剤８７
３００７で処理して、結晶のホスホフィライト状態を電
子顕微鏡で観察した。(2) Phosphate treatment test Phosphate treatment agent 87 manufactured by Nippon Parker Linong Co., Ltd.
3007, and the phosphophyllite state of the crystals was observed using an electron microscope.
（３）電着塗装性試験
上記りンａＩ塩処理剤で２−０〜２−５９／ｍ”の虚腔
を形成した後、日本ペイント（株）製カチオン電着塗料
Ｕ−１００を乾燥塗膜厚で２０μｍ塗装し、塗膜クレー
タ−の発生状態を観察した。(3) Electrodeposition coating property test After forming a void of 2-0 to 2-59/m" with the above phosphorus aI salt treatment agent, dry coating with cationic electrodeposition paint U-100 manufactured by Nippon Paint Co., Ltd. The coating was applied to a film thickness of 20 μm, and the occurrence of coating film craters was observed.
その後−この塗装鋼板にめっき層に達するスクラッチを
カッターナイフで入れて、塩水噴霧試験を１０′００時
間行った後、スクラッチ部をテーピング剥離して耐食性
を調査するとともに、スクラッチ部以外の部分にゴバン
目（２ｍｍ間隔で１００個）をカッターナイフで入れて
、テーピング剥離により塗膜剥離状況（耐水二次密着性
）を調査した。Afterwards, scratches reaching the plating layer were made on this painted steel plate using a cutter knife, and a salt spray test was conducted for 10'00 hours.The scratched area was peeled off with tape to investigate corrosion resistance, and the area other than the scratched area was Eyes (100 pieces at 2 mm intervals) were made with a cutter knife, and the state of paint film peeling (water resistant secondary adhesion) was investigated by taping and peeling.
以上のごとく本発明のめっき鋼板は従来のＺｎ −Ｆｅ
系合金めっき鋼板より裸耐食性に優れており、またリン
酸塩処理性が優れていることから、電着塗装性も向上す
る。さらに１工程でめっきで終るので、コスト上昇を招
かない。As described above, the plated steel sheet of the present invention is different from the conventional Zn-Fe plated steel sheet.
It has better bare corrosion resistance than alloy-plated steel sheets, and has better phosphate treatment properties, so it also improves electrodeposition coating properties. Furthermore, since plating is completed in one step, there is no increase in costs.
添付図面はＺｎ−２０％Ｆｅ合金電気めっき鋼板のめっ
外層にＭｇを添加した場合のＭｇ添加量と塩水噴霧試験
による腐食減量との関係を示すグラフである。The attached drawing is a graph showing the relationship between the amount of Mg added and the corrosion weight loss in a salt spray test when Mg is added to the outer plating layer of a Zn-20% Fe alloy electroplated steel sheet.
Claims (1)
合金電気めっき鋼板のめっき層にＭｇを０．０５〜２％
添加したことを特徴とする耐食性および電着塗装性に優
れた表面処理鋼板。Adding 0.05 to 2% Mg to the plating layer of a Zn-Fe alloy electroplated steel sheet with an Fe content of 10 to 30% by weight
A surface-treated steel sheet with excellent corrosion resistance and electrodeposition coating properties.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2520787A JPS63192890A (en) | 1987-02-05 | 1987-02-05 | Surface treated steel sheet having superior corrosion resistance and suitability to coating by electrodeposition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2520787A JPS63192890A (en) | 1987-02-05 | 1987-02-05 | Surface treated steel sheet having superior corrosion resistance and suitability to coating by electrodeposition |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63192890A true JPS63192890A (en) | 1988-08-10 |
Family
ID=12159508
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2520787A Pending JPS63192890A (en) | 1987-02-05 | 1987-02-05 | Surface treated steel sheet having superior corrosion resistance and suitability to coating by electrodeposition |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63192890A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013151734A (en) * | 2011-12-26 | 2013-08-08 | Nippon Steel & Sumitomo Metal Corp | Electrogalvanized steel sheet for high image clarity coating substrate excellent in corrosion resistance after coating and enamel hair resistance, and method for producing the same |
-
1987
- 1987-02-05 JP JP2520787A patent/JPS63192890A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013151734A (en) * | 2011-12-26 | 2013-08-08 | Nippon Steel & Sumitomo Metal Corp | Electrogalvanized steel sheet for high image clarity coating substrate excellent in corrosion resistance after coating and enamel hair resistance, and method for producing the same |
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