JPS6363626B2 - - Google Patents
Info
- Publication number
- JPS6363626B2 JPS6363626B2 JP60136378A JP13637885A JPS6363626B2 JP S6363626 B2 JPS6363626 B2 JP S6363626B2 JP 60136378 A JP60136378 A JP 60136378A JP 13637885 A JP13637885 A JP 13637885A JP S6363626 B2 JPS6363626 B2 JP S6363626B2
- Authority
- JP
- Japan
- Prior art keywords
- bath
- zinc
- hot
- aluminum
- dip galvanizing
- 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.)
- Expired
Links
- 239000011701 zinc Substances 0.000 claims description 25
- 238000005246 galvanizing Methods 0.000 claims description 22
- 229910052725 zinc Inorganic materials 0.000 claims description 19
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 18
- 229910001297 Zn alloy Inorganic materials 0.000 claims description 14
- FJMNNXLGOUYVHO-UHFFFAOYSA-N aluminum zinc Chemical compound [Al].[Zn] FJMNNXLGOUYVHO-UHFFFAOYSA-N 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 11
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 9
- 239000011777 magnesium Substances 0.000 claims description 8
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 5
- 229910052749 magnesium Inorganic materials 0.000 claims description 5
- 238000007747 plating Methods 0.000 description 14
- 238000005260 corrosion Methods 0.000 description 10
- 230000007797 corrosion Effects 0.000 description 10
- 239000010408 film Substances 0.000 description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 230000004907 flux Effects 0.000 description 6
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- JIAARYAFYJHUJI-UHFFFAOYSA-L zinc dichloride Chemical compound [Cl-].[Cl-].[Zn+2] JIAARYAFYJHUJI-UHFFFAOYSA-L 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 3
- 235000019270 ammonium chloride Nutrition 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 235000015067 sauces Nutrition 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 235000005074 zinc chloride Nutrition 0.000 description 2
- 239000011592 zinc chloride Substances 0.000 description 2
- 229910018137 Al-Zn Inorganic materials 0.000 description 1
- 229910018573 Al—Zn Inorganic materials 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000000460 chlorine Substances 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005238 degreasing Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005554 pickling Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Landscapes
- Coating With Molten Metal (AREA)
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明はボルトのねじ山等のように凹凸を有す
る鉄鋼製品の表面処理に最適であり、めつき厚が
薄くかつ耐食性に優れた亜鉛めつきを行うことが
可能な溶融亜鉛めつき方法に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention is ideal for surface treatment of iron and steel products with unevenness such as bolt threads, and is a zinc plate with a thin plating thickness and excellent corrosion resistance. The present invention relates to a hot-dip galvanizing method that allows galvanizing.
［背景技術及び解決すべき事項］
一般的にねじ山を有するボルト等の表面処理に
は亜鉛めつきが広く用いられている。電気亜鉛め
つきは膜厚が薄く耐食性が悪い。又溶融亜鉛めつ
きの場合にはJISH―8641に規定する条件を満足
するためにはこの場合のめつき膜厚は50μm以上
であることが必要であり、この膜厚が薄過ぎると
防錆効果が不充分である。また厚過ぎると、ボル
トのねじ山、外径を大きくし、ナツトとの螺合が
不完全になるので、めつき後にねじ山外径を所望
量だけ削りとる等の作業が必要になる。[Background Art and Issues to be Solved] Generally, galvanizing is widely used for surface treatment of threaded bolts and the like. Electrogalvanizing has a thin film and poor corrosion resistance. In addition, in the case of hot-dip galvanizing, in order to satisfy the conditions specified in JISH-8641, the plating film thickness in this case must be 50 μm or more, and if this film thickness is too thin, the rust prevention effect will be reduced. It is insufficient. If it is too thick, the thread and outer diameter of the bolt will be increased and the threading with the nut will be incomplete, so it will be necessary to remove the outer diameter of the thread by the desired amount after plating.
溶融亜鉛めつきは耐食性は優れているが、被膜
厚の均一さに欠け、被膜精度が悪い。 Hot-dip galvanizing has excellent corrosion resistance, but lacks uniformity in coating thickness and poor coating precision.
このため従来、薄肉の亜鉛被膜を形成する目的
で480℃〜560℃の溶融亜鉛めつき浴に被めつき物
を浸漬する高温溶融亜鉛めつきも採用されている
が、亜鉛被膜が薄くなるので、これに応じて耐食
性も低下する。 For this reason, high-temperature hot-dip galvanizing, in which the object to be coated is immersed in a hot-dip galvanizing bath at 480°C to 560°C, has been used in the past to form a thin zinc coating, but the zinc coating becomes thinner. , Corrosion resistance also decreases accordingly.
溶融亜鉛浴に少量のアルミニウム（Al）、又は
これにマグネシウム（Mg）を少量加え、被めつ
き物の表面にアルミニウム亜鉛合金めつきを施す
方法も用いられている（一例として特開昭59―
166664号）。これによつて単に亜鉛めつきを施す
場合に比べてより耐食性に優れためつき膜を形成
することが可能ではあるが、このめつき膜厚は
5μm程度である。 Another method is to add a small amount of aluminum (Al) or magnesium (Mg) to a molten zinc bath and apply an aluminum-zinc alloy plating to the surface of the object to be plated (for example, Japanese Patent Application Laid-Open No. 1983-1999)
No. 166664). This makes it possible to form a plating film with better corrosion resistance than when simply galvanizing, but the thickness of this plating film is
It is about 5 μm.
さらに前記のように溶融亜鉛めつき浴にアルミ
ニウムを含ませてめつきを行う場合には、溶融亜
鉛浴内のアルミニウムと塩化亜鉛、塩化アンモニ
ウムの塩素が結合してフラツクスを破壊し不めつ
き状態となる箇所もあるため、特殊フラツクス
（一例として特開昭58−136759号に開示されてい
る）を用いる必要がある。しかしこの特殊フラツ
クスを用いた場合にもさらにめつきの耐食性を向
上するために溶融亜鉛浴にMgを入れた場合には
不めつきが発生しやすい。 Furthermore, when plating is performed by impregnating aluminum in the hot-dip galvanizing bath as described above, the aluminum in the hot-dip galvanizing bath combines with the chlorine of zinc chloride and ammonium chloride to destroy the flux, resulting in an unspotted state. Therefore, it is necessary to use a special flux (as disclosed in Japanese Patent Application Laid-Open No. 136759/1983). However, even when this special flux is used, if Mg is added to the molten zinc bath to further improve the corrosion resistance of the plating, failure is likely to occur.
本発明は上記事実を考慮し、耐食性に優れ、か
つ膜厚の薄い亜鉛めつき層が施された被めつき物
を得ることが可能な溶融亜鉛めつき方法を提供す
ることを目的としている。 The present invention has been made in consideration of the above facts, and an object of the present invention is to provide a hot-dip galvanizing method capable of obtaining a galvanized object having excellent corrosion resistance and a thin galvanized layer.
［発明の概要］
本発明に係る溶融亜鉛めつき方法では、被めつ
き物を500〜600℃の溶融亜鉛浴に浸漬し、これか
ら取り出した後に直ちに450℃以下の溶融アルミ
亜鉛合金浴に浸漬することを特徴としている。[Summary of the invention] In the hot-dip galvanizing method according to the present invention, the object to be plated is immersed in a molten zinc bath at 500 to 600°C, and after being taken out from there, it is immediately immersed in a molten aluminum-zinc alloy bath at 450°C or less. It is characterized by
すなわち本発明では被めつき物を脱脂、酸洗し
た後にフラツクス槽へ浸漬し、この被めつき物を
500〜600℃の比較的高温の溶融亜鉛めつき浴に浸
漬する。この溶融亜鉛めつき浴は一般的に行われ
る溶融亜鉛めつきの温度（440℃〜480℃）に比較
してかなり高く、これによつて薄くて均一なFe
―Zn合金層を安定して形成させることができる。
この溶融亜鉛浴の温度はさらに好ましくは530℃
〜560℃である。 That is, in the present invention, the coated material is degreased and pickled, and then immersed in a flux bath.
Immerse in a hot-dip galvanizing bath at a relatively high temperature of 500-600℃. The temperature of this hot-dip galvanizing bath is considerably higher than that of conventional hot-dip galvanizing (440°C to 480°C), which allows for thin and uniform galvanizing.
- A Zn alloy layer can be formed stably.
The temperature of this molten zinc bath is more preferably 530°C.
~560℃.
溶融亜鉛浴から取り出した被めつき物は直ち
に、即ち被めつき物の温度が大きく低下しないで
かつ表面のFe―Zn合金層の外側の純亜鉛層が酸
化しない間に溶融アルミ亜鉛合金浴に浸漬する。
この溶融アルミ亜鉛合金浴は450℃以下であり、
好ましくは400℃〜450℃とする。この溶融アルミ
亜鉛合金浴の温度が高いと、被めつき物の表面に
形成された合金層が剥離する原因となり、またこ
の温度が低いと合金層の外側に形成されているア
ルミ亜鉛層のタレ切り性が悪くなつて膜厚が厚く
なる。 The coated object taken out from the molten zinc bath is immediately transferred to the molten aluminum-zinc alloy bath before the temperature of the coated object drops significantly and the pure zinc layer outside the Fe-Zn alloy layer on the surface is not oxidized. Soak.
This molten aluminum zinc alloy bath is below 450℃,
Preferably the temperature is 400°C to 450°C. If the temperature of this molten aluminum-zinc alloy bath is high, the alloy layer formed on the surface of the object to be plated will peel off, and if this temperature is low, the aluminum-zinc layer formed on the outside of the alloy layer will sag. Cutting performance becomes worse and the film becomes thicker.
この溶融アルミ亜鉛合金浴には少なくとも５％
程度のアルミニウムを含めることが好ましく、さ
らに好ましくは亜鉛に対して0.2〜2.0％程度のマ
グネシウムを含めることによりアルミニウム及び
マグネシウムをFe―Zn層へ拡散させ、このFe―
Zn層とAl―Zn乃至はAl―Mg―Znの合金の入れ
替わりにより、全体としてAl乃至はAl―Mgを含
んだ合金めつき被膜を形成して耐食性を向上させ
る。 The molten aluminum-zinc alloy bath contains at least 5%
It is preferable to include about 0.2 to 2.0% of aluminum, and more preferably about 0.2 to 2.0% of magnesium to zinc, so that aluminum and magnesium are diffused into the Fe--Zn layer.
By replacing the Zn layer with an alloy of Al--Zn or Al--Mg--Zn, an alloy plating film containing Al or Al--Mg is formed as a whole, improving corrosion resistance.
必要に応じて溶融アルミ亜鉛合金浴から取り出
した被めつき物は遠心分離機等でタレ切りを行つ
て、めつき層の膜厚を調整し、その後冷却してめ
つきを完了する。 If necessary, the plated material taken out from the molten aluminum-zinc alloy bath is drained using a centrifuge or the like to adjust the thickness of the plating layer, and then cooled to complete the plating.
［発明の実施例］
実施例 １
M10の鉄製ボルト（JISB0205による）を第１
図に示される如く、脱脂槽１０へ浸漬し、水洗後
に酸洗槽１２へ浸漬し、フラツクス槽１４（塩化
亜鉛、塩化アンモニウム）へ浸漬し、取出して乾
燥させた後に、540℃に加熱した溶融亜鉛浴１６
に30秒浸漬させ、これを取り出した後に引き続き
５％のアルミニウムを含む溶融亜鉛浴１８に30秒
浸漬して取り出し、遠心分離によつてタレ切りを
行い水冷しめつき層を安定させた。[Embodiments of the invention] Example 1 M10 iron bolts (according to JISB0205) were
As shown in the figure, it was immersed in a degreasing tank 10, washed with water, immersed in a pickling tank 12, immersed in a flux tank 14 (zinc chloride, ammonium chloride), taken out and dried, and then heated to 540°C. Zinc bath 16
After taking it out, it was subsequently immersed in a molten zinc bath 18 containing 5% aluminum for 30 seconds and taken out, and the water-cooled tightening layer was stabilized by removing the sauce by centrifugation.
この実施例によつて第２図に示される如く、ボ
ルトねじ山２０の外周へそれぞれAlが拡散され
たFe―Al―Zn層２２とAl―Zn層２４とからなる
めつき層が形成され、めつき膜厚は約15μmであ
り、ナツトとの螺合も円滑であつた。 According to this embodiment, as shown in FIG. 2, a plating layer consisting of an Fe--Al--Zn layer 22 and an Al--Zn layer 24 in which Al is diffused is formed on the outer periphery of the bolt thread 20. The plating film thickness was about 15 μm, and the screwing with the nut was smooth.
またこのボルトをJISZ―2371に規定する塩水
噴霧試験方法で試験を行つた結果、480時間（20
日間）を経過しても赤錆の発生がなく、他のめつ
きに比較して著しく優れた耐食性を得ることがで
きた。 In addition, this bolt was tested using the salt spray test method specified in JISZ-2371, and the result was 480 hours (20 hours).
No red rust occurred even after several days, and significantly superior corrosion resistance was achieved compared to other platings.
実施例 ２
第１実施例と同様の手順でフラツクスを塗布し
たM10の鉄製ボルトを540℃に加熱した溶融亜鉛
浴に30秒浸漬させ、これを取り出した後に引き続
いて５％のアルミニウム及び１％のマグネシウム
を含む溶融亜鉛浴に30秒浸漬し、引き出した後に
遠心分離によりタレ切りを行つて水冷した。Example 2 An M10 iron bolt coated with flux was immersed in a molten zinc bath heated to 540°C for 30 seconds in the same manner as in the first example, and after being taken out, 5% aluminum and 1% aluminum were added. It was immersed in a molten zinc bath containing magnesium for 30 seconds, taken out, centrifuged to remove any sauce, and cooled in water.
このボルトは第１実施例と同程度の膜厚であ
り、前記実施例１と同様の塩水噴霧試験に従つて
試験を行つたところ、720時間（30日間）を経過
しても赤錆の発生はなかつた。 This bolt has a film thickness similar to that of the first example, and when tested according to the same salt spray test as in the first example, no red rust occurred even after 720 hours (30 days). Nakatsuta.
［発明の効果］
以上説明した如く本発明に係る溶融亜鉛めつき
方法では、被めつき物を500〜600℃の溶融亜鉛浴
に浸漬し、これから取り出した後に直ちに450℃
以下の溶融アルミ亜鉛合金浴に浸漬するので、薄
くかつ耐食性に優れた被めつき物を得ることが可
能となる優れた効果を有する。[Effects of the Invention] As explained above, in the hot-dip galvanizing method according to the present invention, the object to be plated is immersed in a molten zinc bath at 500 to 600°C, and immediately after being taken out from the bath, it is heated to 450°C.
Since it is immersed in the following molten aluminum-zinc alloy bath, it has the excellent effect of making it possible to obtain a coated object that is thin and has excellent corrosion resistance.
第１図は本発明の実施例に係る溶融亜鉛めつき
方法を実施する手順を示す説明図、第２図は第１
実施例によつてめつきを施したボルトねじ山の拡
大断面図である。
１６……溶融亜鉛浴、１８……溶融アルミ亜鉛
浴、２０……ボルトねじ山、２２……Fe―Al―
Zn層、２４……Al―Zn層。
FIG. 1 is an explanatory diagram showing the procedure for carrying out the hot-dip galvanizing method according to the embodiment of the present invention, and FIG.
FIG. 2 is an enlarged sectional view of a bolt thread plated according to an embodiment. 16... Molten zinc bath, 18... Molten aluminum zinc bath, 20... Bolt thread, 22... Fe-Al-
Zn layer, 24...Al-Zn layer.
Claims (1)
し、これから取り出した後に直ちに450℃以下の
溶融アルミ亜鉛合金浴に浸漬することを特徴とし
た溶融亜鉛めつき方法。 ２ 前記溶融亜鉛浴は530℃〜560℃、溶融アルミ
亜鉛合金浴は400℃〜450℃であることを特徴とし
た前記特許請求の範囲第１項に記載の溶融亜鉛め
つき方法。 ３ 前記溶融アルミ亜鉛合金浴は３〜７％のアル
ミが含まれていることを特徴とした前記特許請求
の範囲第１項又は第２項に記載の溶融亜鉛めつき
方法。 ４ 前記溶融アルミ亜鉛合金浴には0.2〜2.0％の
マグネシウムが含まれることを特徴とした前記特
許請求の範囲第１項〜第３項のいずれか一項に記
載の溶融亜鉛めつき方法。[Scope of Claims] 1. Hot-dip galvanizing characterized by immersing the object to be plated in a molten zinc bath at 500 to 600°C, and after taking it out from there, immediately immersing it in a molten aluminum-zinc alloy bath at 450°C or lower. Method. 2. The hot dip galvanizing method according to claim 1, wherein the temperature of the molten zinc bath is 530°C to 560°C, and the temperature of the molten aluminum zinc alloy bath is 400°C to 450°C. 3. The hot-dip galvanizing method according to claim 1 or 2, wherein the molten aluminum-zinc alloy bath contains 3 to 7% aluminum. 4. The hot-dip galvanizing method according to any one of claims 1 to 3, wherein the molten aluminum-zinc alloy bath contains 0.2 to 2.0% magnesium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13637885A JPS61295361A (en) | 1985-06-21 | 1985-06-21 | Hot dip galvanizing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13637885A JPS61295361A (en) | 1985-06-21 | 1985-06-21 | Hot dip galvanizing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61295361A JPS61295361A (en) | 1986-12-26 |
| JPS6363626B2 true JPS6363626B2 (en) | 1988-12-08 |
Family
ID=15173756
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13637885A Granted JPS61295361A (en) | 1985-06-21 | 1985-06-21 | Hot dip galvanizing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61295361A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01263255A (en) * | 1988-04-14 | 1989-10-19 | Nippon Aen Kogyo Kk | Aluminum-zinc alloy hot dipping method with high coating weight |
| JPH07109556A (en) * | 1993-10-08 | 1995-04-25 | Shinko Kosen Kogyo Kk | Alloy layer coated steel wire and its production |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5230233A (en) * | 1975-09-02 | 1977-03-07 | Nippon Kokan Kk | Melttplating method of aluminummzing alloy |
| JPS5735672A (en) * | 1980-08-11 | 1982-02-26 | Nippon Mining Co Ltd | Galvanizing method providing high corrosion resistance |
-
1985
- 1985-06-21 JP JP13637885A patent/JPS61295361A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5230233A (en) * | 1975-09-02 | 1977-03-07 | Nippon Kokan Kk | Melttplating method of aluminummzing alloy |
| JPS5735672A (en) * | 1980-08-11 | 1982-02-26 | Nippon Mining Co Ltd | Galvanizing method providing high corrosion resistance |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61295361A (en) | 1986-12-26 |
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