JPH0533312B2 - - Google Patents
Info
- Publication number
- JPH0533312B2 JPH0533312B2 JP61215548A JP21554886A JPH0533312B2 JP H0533312 B2 JPH0533312 B2 JP H0533312B2 JP 61215548 A JP61215548 A JP 61215548A JP 21554886 A JP21554886 A JP 21554886A JP H0533312 B2 JPH0533312 B2 JP H0533312B2
- Authority
- JP
- Japan
- Prior art keywords
- hot
- sio
- plating layer
- corrosion resistance
- dip galvanized
- 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 - Lifetime
Links
- 238000011282 treatment Methods 0.000 claims description 29
- 238000007747 plating Methods 0.000 claims description 28
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical compound [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 claims description 26
- 229910001335 Galvanized steel Inorganic materials 0.000 claims description 18
- 239000008397 galvanized steel Substances 0.000 claims description 18
- 238000005260 corrosion Methods 0.000 claims description 17
- 230000007797 corrosion Effects 0.000 claims description 17
- 238000012545 processing Methods 0.000 claims description 13
- 239000007864 aqueous solution Substances 0.000 claims description 11
- 239000000243 solution Substances 0.000 claims description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 9
- PAZHGORSDKKUPI-UHFFFAOYSA-N lithium metasilicate Chemical compound [Li+].[Li+].[O-][Si]([O-])=O PAZHGORSDKKUPI-UHFFFAOYSA-N 0.000 claims description 9
- 229910052912 lithium silicate Inorganic materials 0.000 claims description 9
- 229910000831 Steel Inorganic materials 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 8
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 8
- 238000002844 melting Methods 0.000 claims description 6
- 239000007921 spray Substances 0.000 claims description 6
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 5
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 5
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims description 5
- 239000002131 composite material Substances 0.000 claims description 4
- 239000007788 liquid Substances 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- -1 oxalate ions Chemical class 0.000 claims description 4
- 229910052744 lithium Inorganic materials 0.000 claims description 3
- 238000000034 method Methods 0.000 description 18
- 239000010410 layer Substances 0.000 description 16
- 238000005507 spraying Methods 0.000 description 9
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- 238000002845 discoloration Methods 0.000 description 4
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 239000011701 zinc Substances 0.000 description 4
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 3
- 238000005452 bending Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910000611 Zinc aluminium Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- HXFVOUUOTHJFPX-UHFFFAOYSA-N alumane;zinc Chemical compound [AlH3].[Zn] HXFVOUUOTHJFPX-UHFFFAOYSA-N 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005034 decoration Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052909 inorganic silicate Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 description 1
- 229910052745 lead Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- 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
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/60—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using alkaline aqueous solutions with pH greater than 8
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
- Coating With Molten Metal (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Description
（産業上の利用分野）
本発明は溶融めつき後機械的処理加工を施した
り、クロメート処理を施しても表面が灰黒色に変
色しにくい耐食性、耐機械的加工性に優れた溶融
めつき鋼板の製造方法に関する。
（従来技術）
溶融亜鉛めつき鋼板、溶融アルミニウムめつき
鋼板などの溶融めつき鋼板の用途は従来屋根や壁
などが主であつたが、近年は耐久材としての需要
が益々高まり、内装、器物など高度の外観、形状
および加工性を必要とする方面に用途が拡大して
きている。このため溶融めつき鋼板の製造に際し
ては、品質向上を目的とする種々の後処理方法が
検討されている。例えばめつき後付着量を調整し
た直後の未凝固めつき層に霧状水滴を吹付けて急
冷することによりスパングルをミニマイズド化し
て外観を向上させたり、めつき層の凝固後に種々
の機械的処理加工（例えばレベラー、スキンパ
ス）を施して、外観、形状および加工性などを向
上させたりする方法などである。
（発明が解決しようとする問題点）
しかしながらこのようにスパングルをミニマイ
ズド化したものに機械的処理加工を施したり、耐
食性や塗膜密着性改善のためにクロメート処理を
施すと、通常の保管状態でも数箇月という比較的
短期間に表面が灰黒色（以下黒変という）に変色
し、銀白色の外観が失われてしまう。
このため黒変を軽くもしくは目立たないように
するには非クロム酸系の後処理を使用すればよい
のであるが、非クロム酸系の後処理は一般に処理
費が高く、機械的処理加工にも弱いという欠点が
ある。
例えば本発明者らは先に耐黒変性、耐食性を兼
ね備えた非クロム酸系の後処理方法として、Ni、
Co、Feイオンを１種または２種以上含む処理液
で溶融めつき鋼板を予め表面調整して、それらの
金属をめつき層表面に置換析出させた後、無機系
シリケート処理剤の処理液を塗布して乾燥するこ
とによりシリケート皮膜を形成する方法を提案し
たが、この方法は工程が複雑になるので、複雑で
ある。また皮膜はガラス質のシリケート皮膜が単
にめつき層表面に付着しているのに過ぎないの
で、皮膜の付着力は弱く、ロールフオーミング、
プレスまたは折曲げなどの加工によりしごきを受
けたりすると、皮膜は容易に破壊、剥脱してしま
う。このため黒変発生を抑制するには後処理方法
を安価で、機械的処理加工に耐えるものにする必
要があつた。
（問題点を解決するための手段）
そこで本発明者らは安価で、機械的加工に耐え
る後処理方法を検討した結果、めつき層が溶融状
態にあるうちにめつき層表面にシリカゾル、アル
ミナゾル、リチウムシリケートの１種または２種
以上を含む水系溶液を吹付け、めつき層表層にめ
つき層と一体になつたガラス質皮膜を形成する方
法およびそのガラス質皮膜の上にクロメート処理
を施して、クロメート皮膜を形成する方法を開発
した。
本発明はこの後処理方法を溶融めつき鋼板製造
の際利用して耐食性、耐機械的加工性に優れた溶
融めつき鋼板を製造するもので、鋼板に溶融めつ
きを施して、めつき付着量を調整した後、めつき
層が溶融状態にあるうちにめつき層表面にシリカ
ゾル、アルミナゾル、リチウムシリケートの１種
または２種以上を含む水系溶液を吹付け、めつき
層表層にSiO2、Al2O3、Li2SiO3の単独または混
合物からなる複合酸化皮膜を形成し、また前記水
系溶液の吹付け後クロメート処理を施して酸化皮
膜の上にクロメート皮膜を形成するのである。
この方法によれば水系溶液の吹付けは従来連続
溶融めつき設備にスパングルをミニマイズド化す
るのに設置してある吹付け装置を使用して行えば
よいので、工程は従来のミニマイズドスパングル
の溶融めつき鋼板製造と同じである。従つて工程
的には安価である。また、水系溶液はめつき層が
溶融状態にあるとき吹付けるのであるから、
SiO2、Al2O3、Li2SiO3などのガラス質皮膜はめ
つき層と一体になり、耐機械的加工に優れてい
る。
本発明で水系溶液に含ませるシリカゾル、アル
ミナゾル、リチウムシリケートは市販のものでよ
く、例えば日産化学工業(株)製のスノーテツクス
Ｏ、スノーテツクスＣ、アルミナゾル200、リチ
ウムシリケートLSS35、リチウムシリケート
LSS45などを使用すればよい。溶液の濃度や温度
などはとくに限定はない。
溶液の溶融めつき鋼板への吹付けはめつき層が
溶融状態にあるうちに行うのであるが、その吹付
け量は金属換算で付着量が0.2〜200mg／m2になる
ようにする。0.2mg／m2未満であると、耐食性、
黒変防止効果が不十分であり、200mg／m2を越え
て付着させても、必要以上に生成した酸化皮膜の
大部分が鋼板加工後の際破壊されて脱落し、製造
コストが高くなる。
本発明では以上のようにして処理液を吹着け
て、めつき層表層にSiO2、Al2O3、Li2SiO3の単
独または混合物からなる複合酸化皮膜を形成した
後、さらにクロメート処理を施し、酸化皮膜の上
にクロメート皮膜を形成する。クロメート処理を
施すのは、金属酸化物皮膜を形成しただけでも黒
変防止も含めて長期間耐食性を発揮するが、さら
に耐食性を向上させるとともに、塗膜密着性をも
付与さるためである。
使用するクロメート処理液としては、無水クロ
ム酸を主体に溶解したもので、Cr3+／（Cr3+＋
Cr6+）＝０〜0.6に調整したものが最も望ましい。
Cr3+とCr6+とがこのような組成のクロメート処理
液は公知のクロメート処理液として知られている
が、本発明の場合そのまま使用するには問題があ
る場合がある。これは公知のクロメート処理液の
ほとんどのものには反応促進剤や亜鉛表面を適度
にエツチングするエツチング成分が添加されてい
るため、それらにより亜鉛が溶解されて、金属酸
化物皮膜も脱落し、耐黒変性効果が失なわれるの
で、好ましくない。このため本発明で使用するク
ロメート処理液としてはF-、Cl-、SO4 2-、
NO3 -、PO4 3-、CH3COO-、しゆう酸イオンなど
の陰イオンからなるエツチング成分を含有しない
ものを使用するのが好ましい。
本発明の製造方法は溶融めつき鋼板が溶融亜鉛
系、溶融アルミニウム系、溶融亜鉛−アルミニウ
ム系合金であつても、またそれらにMg、Si、希
土類元素などを添加したものであつても黒変を抑
制できる。
以下実施例により本発明を説明する。
（実施例）
実施例 １
重量％で、Al 0.17％、Pb 0.30％、Fe 0.03％、
残部Znおよび不可避的不純物からなるめつき浴
で鋼板を溶融めつきした後、気体絞り法によりめ
つき付着量を200〜250ｇ／m2に調整し、第１表に
示す塩の水溶液を２〜３Kg／cm2の圧縮空気で霧化
して吹付け、溶融亜鉛めつき鋼板を製造した。そ
の後この鋼板の一部をCrO3 20ｇ／、温度40℃
の無水クロム酸水溶液中に５秒間浸漬して、クロ
メート処理を施した。
次にこれらのクロメート未処理と処理の溶融亜
鉛めつき鋼板より試験片を採取して、その一部を
温度50±１℃、相対湿度98％以上の雰囲気中にク
ロメート未処理のものは１日間、またクロメート
処理のものは30日間放置することにより黒変促進
試験を行い、また残りの試験片には4t曲げおよび
エリクセン６mm押出加工を施した後、JIS Ｚ
2371に規定された塩水噴霧試験に準じて耐食性促
進試験を実施した。塩水噴霧試験はクロメート未
処理のものの場合８時間、クロメート処理のもの
の場合100時間実施した。この第１表にこの促進
試験結果を示す。なお第１表における耐食性促進
試験のフラツト部は4t曲げおよびエリクセン６mm
押出加工を施さない部分であり、加工部はこれら
の加工を施した部分である。
なお黒変、耐食性の判定は次の基準により行つ
た。
(1) 黒変促進試験
◎ 黒変せず
○ 極く薄く灰色化した
△ 黒変の面積が全体の30％未満
× 黒変の面積が全体の30％以上
(2) 耐食性促進試験
◎ 錆が発生せず
○ 錆の発生面積が10％未満
△ 錆の発生面積が全体の10〜30％未満
× 錆の発生面積が全体の30％以上
(Industrial Application Field) The present invention is a hot-dip galvanized steel sheet that has excellent corrosion resistance and mechanical processability, and the surface does not easily change color to grayish black even if subjected to mechanical treatment or chromate treatment after hot-dip galvanization. Relating to a manufacturing method. (Prior art) Hot-dip galvanized steel sheets, hot-dip aluminum-plated steel sheets, and other hot-dip galvanized steel sheets have traditionally been used mainly for roofs and walls, but in recent years demand as durable materials has increased, and they have been used for interior decorations and utensils. Applications are expanding to areas that require a high degree of appearance, shape, and workability. For this reason, when producing hot-dip galvanized steel sheets, various post-treatment methods are being considered for the purpose of improving quality. For example, spraying atomized water droplets on the unsolidified plating layer immediately after adjusting the coating amount after plating and rapidly cooling it minimizes spangles and improves the appearance, or various mechanical treatments can be applied after the plating layer solidifies. These methods include applying processing (for example, leveler, skin pass) to improve the appearance, shape, workability, etc. (Problem to be solved by the invention) However, if spangles are minimized in this way and subjected to mechanical processing or chromate treatment to improve corrosion resistance and paint film adhesion, even under normal storage conditions, Within a relatively short period of several months, the surface turns grayish-black (hereinafter referred to as black discoloration) and loses its silvery white appearance. For this reason, non-chromate-based post-treatments can be used to make the blackening lighter or less noticeable, but non-chromate-based post-treatments are generally expensive and are not suitable for mechanical processing. It has the disadvantage of being weak. For example, the present inventors previously proposed a non-chromic acid post-treatment method that combines blackening resistance and corrosion resistance.
After preparing the surface of a hot-dip galvanized steel sheet in advance with a treatment solution containing one or more types of Co and Fe ions and displacing and depositing these metals on the surface of the plating layer, a treatment solution containing an inorganic silicate treatment agent is applied. A method of forming a silicate film by coating and drying has been proposed, but this method is complicated because the steps are complicated. In addition, since the film is simply a glassy silicate film attached to the surface of the plating layer, the adhesion of the film is weak and roll forming occurs.
If the film is subjected to stress through processing such as pressing or bending, the film will easily break and peel off. Therefore, in order to suppress the occurrence of blackening, it was necessary to use a post-processing method that was inexpensive and resistant to mechanical processing. (Means for solving the problem) The present inventors investigated a post-treatment method that is inexpensive and resistant to mechanical processing, and found that silica sol and alumina sol were applied to the surface of the plating layer while it was in a molten state. , a method of spraying an aqueous solution containing one or more types of lithium silicates to form a glassy film on the surface of the plating layer that is integrated with the plating layer, and a method of performing chromate treatment on the glassy film. We developed a method to form a chromate film. The present invention utilizes this post-treatment method during the production of hot-dip galvanized steel sheets to produce hot-dip galvanized steel sheets with excellent corrosion resistance and mechanical workability. After adjusting the amount, while the plating layer is in a molten state, an aqueous solution containing one or more of silica sol, alumina sol, and lithium silicate is sprayed onto the surface of the plating layer to coat the surface of the plating layer with SiO 2 , A composite oxide film consisting of Al 2 O 3 and Li 2 SiO 3 alone or in combination is formed, and after the aqueous solution is sprayed, a chromate treatment is performed to form a chromate film on the oxide film. According to this method, the spraying of the aqueous solution can be carried out using the spraying equipment installed in the conventional continuous melting and melting equipment for minimizing spangles, so the process is similar to that of conventional continuous melting and melting It is the same as galvanized steel sheet manufacturing. Therefore, the process is inexpensive. In addition, since the aqueous solution is sprayed when the plating layer is in a molten state,
A glassy coating made of SiO 2 , Al 2 O 3 , Li 2 SiO 3 , etc. is integrated with the plating layer and has excellent mechanical processing resistance. The silica sol, alumina sol, and lithium silicate to be included in the aqueous solution in the present invention may be commercially available products, such as Snowtex O, Snowtex C, Alumina Sol 200, Lithium Silicate LSS35, and Lithium Silicate manufactured by Nissan Chemical Industries, Ltd.
You can use something like LSS45. There are no particular limitations on the concentration or temperature of the solution. The spraying of the solution onto the hot-dip galvanized steel plate is carried out while the galvanized layer is in a molten state, and the spraying amount is set so that the coating amount is 0.2 to 200 mg/m 2 in terms of metal. If it is less than 0.2mg/ m2 , corrosion resistance,
The blackening prevention effect is insufficient, and even if the amount exceeds 200 mg/m 2 , most of the oxide film produced in excess of the necessary amount will be destroyed and fall off after processing the steel sheet, increasing manufacturing costs. In the present invention, after spraying the treatment liquid as described above to form a composite oxide film consisting of SiO 2 , Al 2 O 3 , and Li 2 SiO 3 alone or in combination on the surface layer of the plating layer, a chromate treatment is further performed. to form a chromate film on top of the oxide film. The reason why chromate treatment is applied is that the mere formation of a metal oxide film provides long-term corrosion resistance, including prevention of blackening, but it also improves corrosion resistance and provides paint film adhesion. The chromate treatment solution used is one in which chromic anhydride is mainly dissolved, and Cr 3+ / (Cr 3+ +
Cr 6+ )=0 to 0.6 is most desirable.
A chromate treatment solution having such a composition of Cr 3+ and Cr 6+ is known as a known chromate treatment solution, but there may be problems in using it as is in the present invention. This is because most of the known chromate treatment solutions contain a reaction accelerator and an etching component that moderately etches the zinc surface, which dissolves the zinc and removes the metal oxide film, making it resistant to corrosion. This is not preferred because the blackening effect is lost. Therefore, the chromate treatment liquid used in the present invention includes F - , Cl - , SO 4 2- ,
It is preferable to use a material that does not contain etching components consisting of anions such as NO 3 - , PO 4 3- , CH 3 COO - , and oxalate ions. The manufacturing method of the present invention is applicable to hot-dip galvanized steel sheets, even if they are molten zinc-based, molten aluminum-based, molten zinc-aluminum-based alloys, or those to which Mg, Si, rare earth elements, etc. have been added. can be suppressed. The present invention will be explained below with reference to Examples. (Example) Example 1 In weight%, Al 0.17%, Pb 0.30%, Fe 0.03%,
After melt-plating a steel plate in a plating bath consisting of the remaining Zn and unavoidable impurities, the plating coating amount was adjusted to 200 to 250 g/ m2 by the gas squeezing method, and an aqueous solution of the salt shown in Table 1 was added to the plating bath. A hot-dip galvanized steel sheet was produced by atomizing and spraying with 3 kg/cm 2 of compressed air. After that, a part of this steel plate was treated with 20g of CrO 3 at a temperature of 40°C.
Chromate treatment was performed by immersing the sample in an aqueous chromic acid anhydride solution for 5 seconds. Next, test specimens were taken from these hot-dip galvanized steel sheets, untreated and treated with chromate, and some of them were placed in an atmosphere with a temperature of 50 ± 1°C and a relative humidity of 98% or higher for 1 day. In addition, the chromate-treated specimen was left to stand for 30 days to perform a blackening acceleration test, and the remaining specimens were subjected to 4t bending and Erichsen 6mm extrusion processing, and then JIS Z
An accelerated corrosion resistance test was conducted in accordance with the salt spray test specified in 2371. The salt spray test was conducted for 8 hours for the non-chromate treated samples and for 100 hours for the chromate treated samples. Table 1 shows the results of this accelerated test. In addition, the flat part of the corrosion resistance accelerated test in Table 1 is 4t bending and Erichsen 6mm.
This is the part that is not subjected to extrusion processing, and the processed part is the part that has been subjected to these processes. The black discoloration and corrosion resistance were judged based on the following criteria. (1) Accelerated blackening test ◎ No blackening ○ Very thin graying △ Blackening area is less than 30% of the whole × Blackening area is 30% or more of the whole (2) Accelerated corrosion resistance test ◎ Rust No occurrence ○ Rust occurrence area is less than 10% △ Rust occurrence area is 10 to less than 30% of the whole × Rust occurrence area is 30% or more of the whole
【表】【table】
【表】
実施例 ２
第２表に示すような組成のめつき浴で鋼板を溶
融めつきして、めつき付着量を調整した後、シリ
カゾル、アルミナゾル、リチウムシリケートのい
ずれか１種を50wt％含む水系溶液を吹付け、し
かる後に実施例１同様にクロメート処理して溶融
めつき鋼板を製造した。その後この鋼板より試験
片を採取して、その一部を温度50±１℃、相対湿
度98％以上の雰囲気中に30日間放置することによ
り黒変促進試験を行つた。また採取した残りの試
験片には実施例１と同様の加工を施して、同様に
塩水噴霧試験を８時間、100時間実施した。第２
表に水系溶液の種類と黒変および耐食性の判定結
果を示す。なお黒変と耐食性の判定基準は実施例
１と同じである。[Table] Example 2 After melt-plating a steel plate in a plating bath with the composition shown in Table 2 and adjusting the amount of plating, 50 wt% of any one of silica sol, alumina sol, and lithium silicate was added. A hot-dip galvanized steel sheet was produced by spraying an aqueous solution containing the same, followed by chromate treatment in the same manner as in Example 1. Thereafter, a test piece was taken from this steel plate, and a part thereof was left in an atmosphere with a temperature of 50±1°C and a relative humidity of 98% or more for 30 days to perform a blackening acceleration test. Further, the remaining test pieces taken were processed in the same manner as in Example 1, and similarly subjected to salt spray tests for 8 hours and 100 hours. Second
The table shows the types of aqueous solutions and the judgment results for blackening and corrosion resistance. Note that the criteria for determining black discoloration and corrosion resistance are the same as in Example 1.
【表】【table】
【表】
（発明の効果）
以上のごとく本発明法は非クロム酸系の後処理
であるが、スパングルをミニマイズド化した溶融
めつき鋼板にクロメート処理を施しても、また機
械的加工を施しても黒変の発生を抑制することが
できる。また本発明法はシリカゾル、アルミナゾ
ル、リチウムシリケートなどを含む水系溶液を溶
融めつき直後のめつき層表面に吹付けるだけであ
るので、工程は簡単で、従来のミニマイズドスパ
ングル溶融めつき鋼板と変わらず、安価である。
さらに生成する被膜はめつき層と一体になつた酸
化物皮膜であるので、機械的加工に対して優れて
いる。[Table] (Effects of the invention) As described above, the method of the present invention is a non-chromic acid post-treatment, but even if a hot-dip galvanized steel sheet with minimized spangles is subjected to chromate treatment or mechanical processing is It is also possible to suppress the occurrence of black discoloration. In addition, the process of the present invention is simple, as it simply sprays an aqueous solution containing silica sol, alumina sol, lithium silicate, etc. onto the surface of the plating layer immediately after melt-welding, and it is different from the conventional minimized spangle hot-dip galvanized steel sheet. First, it is inexpensive.
Furthermore, since the resulting film is an oxide film integrated with the plating layer, it is excellent against mechanical processing.
Claims (1)
調整した後、めつき層が溶融状態にあるうちにめ
つき層表面にシリカゾル、アルミナゾル、リチウ
ムシリケートの１種または２種以上を含む水系溶
液を吹付け、めつき層表層にSiO2、Al2O3、
Li2SiO3の単独または混合物からなる複合酸化皮
膜を形成することを特徴とする耐食性、耐加工性
に優れた溶融めつき鋼板の製造方法。 ２ 鋼板に溶融めつきを施して、めつき付着量を
調整した後、めつき層が溶融状態にあるうちにめ
つき層表面にシリカゾル、アルミナゾル、リチウ
ムシリケートの１種または２種以上を含む水系溶
液を吹付け、めつき層表層にSiO2、Al2O3、
Li2SiO3の単独または混合物からなる複合酸化皮
膜を形成し、しかる後にクロメート処理液で処理
して前記酸化物皮膜の上にクロメート皮膜を形成
することを特徴とする耐食性、耐加工性に優れた
溶融めつき鋼板の製造方法。 ３ クロメート処理液として、無水クロム酸を主
体に溶解したもので、Cr3+／（Cr3+＋Cr6+）＝０
〜0.6で、かつF-、Cl-、SO4 2-、NO3 -、PO4 3-、
CH3COO-およびしゆう酸イオンを含有しないも
のであることを特徴とする特許請求の範囲第２項
に記載の耐食性、耐加工性に優れた溶融めつき鋼
板の製造方法。[Claims] 1. After hot-melting a steel plate and adjusting the amount of plating, one of silica sol, alumina sol, lithium silicate, or one of silica sol, alumina sol, lithium silicate, or Spray an aqueous solution containing two or more of SiO 2 , Al 2 O 3 , and
A method for producing a hot-dip galvanized steel sheet with excellent corrosion resistance and workability, characterized by forming a composite oxide film consisting of Li 2 SiO 3 alone or in a mixture. 2. After hot-melting a steel plate and adjusting the amount of plating deposited, an aqueous system containing one or more of silica sol, alumina sol, and lithium silicate is applied to the surface of the plating layer while the plating layer is in a molten state. Spray the solution to coat the surface of the plating layer with SiO 2 , Al 2 O 3 ,
A composite oxide film consisting of Li 2 SiO 3 alone or in a mixture is formed, and then treated with a chromate treatment liquid to form a chromate film on the oxide film. Excellent corrosion resistance and processing resistance. A method for producing hot-dip galvanized steel sheets. 3 The chromate treatment liquid is mainly dissolved in chromic anhydride, and Cr 3+ / (Cr 3+ + Cr 6+ ) = 0
~0.6, and F - , Cl - , SO 4 2- , NO 3 - , PO 4 3- ,
The method for producing a hot-dip galvanized steel sheet with excellent corrosion resistance and workability according to claim 2, characterized in that it does not contain CH 3 COO - and oxalate ions.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21554886A JPS6372887A (en) | 1986-09-12 | 1986-09-12 | Production of hot dip coated steel sheet having excellent corrosion resistance and working resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21554886A JPS6372887A (en) | 1986-09-12 | 1986-09-12 | Production of hot dip coated steel sheet having excellent corrosion resistance and working resistance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6372887A JPS6372887A (en) | 1988-04-02 |
| JPH0533312B2 true JPH0533312B2 (en) | 1993-05-19 |
Family
ID=16674254
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21554886A Granted JPS6372887A (en) | 1986-09-12 | 1986-09-12 | Production of hot dip coated steel sheet having excellent corrosion resistance and working resistance |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6372887A (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2655060A1 (en) * | 1989-11-28 | 1991-05-31 | Allstars Sah | Process and compositions for improving the corrosion resistance of metals and alloys |
| FR2837218B1 (en) * | 2002-03-18 | 2005-02-18 | Dacral Sa | METAL SUBSTRATE COATING COMPOSITION |
| BE1015823A3 (en) | 2003-12-17 | 2005-09-06 | Ct Rech Metallurgiques Asbl | Process for coating a surface by metal layer ultrafine. |
| JP5196916B2 (en) * | 2007-08-30 | 2013-05-15 | 日本パーカライジング株式会社 | Method for surface modification treatment of hot-dip galvanized steel and surface-modified hot-dip metal-plated steel |
| JP5752880B2 (en) * | 2009-11-04 | 2015-07-22 | 日鉄住金鋼板株式会社 | Surface-treated plated steel sheet and manufacturing method thereof |
| DE102011001140A1 (en) * | 2011-03-08 | 2012-09-13 | Thyssenkrupp Steel Europe Ag | Flat steel product, method for producing a flat steel product and method for producing a component |
| JP5356616B1 (en) * | 2012-11-27 | 2013-12-04 | 日新製鋼株式会社 | Method for producing hot-dip Zn alloy-plated steel sheet |
| CN113244881A (en) * | 2021-06-25 | 2021-08-13 | 桂林理工大学 | Method for preparing lithium orthosilicate material by taking KIT-6 as silicon source, modification and application thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50116331A (en) * | 1974-02-26 | 1975-09-11 | ||
| JPS5194429A (en) * | 1975-02-19 | 1976-08-19 | BISAISUPANGURUYO JUAENMETSUKIKOZAINO SEIZOHO |
-
1986
- 1986-09-12 JP JP21554886A patent/JPS6372887A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50116331A (en) * | 1974-02-26 | 1975-09-11 | ||
| JPS5194429A (en) * | 1975-02-19 | 1976-08-19 | BISAISUPANGURUYO JUAENMETSUKIKOZAINO SEIZOHO |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6372887A (en) | 1988-04-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3962501A (en) | Method for coating of corrosion-resistant molten alloy | |
| JPH0321627B2 (en) | ||
| EP0365682B1 (en) | Hot-dip zinc-aluminum alloy coated steel sheet for prepainted steel sheet, process for producing the same and prepainted steel sheet | |
| JPH0533312B2 (en) | ||
| JP3872621B2 (en) | Galvanized steel sheet for automobile bodies | |
| JPH073417A (en) | Highly corrosion resistant galvannealed steel sheet | |
| JPS63297576A (en) | Manufacture of hot-dipped steel sheet excellent in darkish discoloration resistance | |
| KR102018015B1 (en) | Dryinplace corrosionresistant coating for zinc or zincalloy coated substrates | |
| JP2003268518A (en) | Original sheet for coating having excellent workability | |
| JP2566203B2 (en) | Method for producing hot-dip galvanized steel sheet with excellent resistance to blackening | |
| CA2173696C (en) | Zincate-treated article of al-mg-si base alloy and method of manufacturing the same | |
| JPH07331403A (en) | Production of high strength galvannealed steel sheet | |
| JP2001020049A (en) | HOT DIP Zn-Al-Mg PLATED STEEL EXCELLENT IN CORROSION RESISTANCE UNDER NONCOATING AND AFTER COATING AND ITS PRODUCTION | |
| JP2747554B2 (en) | Aluminum / zinc alloy-plated steel sheet and method for producing the same | |
| JPS6250474A (en) | Steel sheet coated with zinc or zinc alloy by hot dipping and having superior blackening eresistance | |
| KR960005024B1 (en) | Method for manufacturing a molten zinc coating steel plate with an excellent corrosion resistant minispangle | |
| JP2001279414A (en) | HOT DIP Zn-Al ALLOY COATED BLACK COLOR STEEL SHEET | |
| JPH042758A (en) | Production of hot-dip zinc alloy coated steel sheet excellent in press formability and corrosion resistance after coating | |
| JPH01222065A (en) | Surface treatment for hot dipped steel sheet | |
| JPH04235266A (en) | Manufacture of alloying galvannealed steel sheet excellent in workability and corrosion resistance | |
| JPS6365088A (en) | Production of hot-dipped steel sheet having excellent blackening resistance | |
| KR960011012B1 (en) | Method for producing a zero-spangle galvanized steel plate with an excellent brightness | |
| JP2772697B2 (en) | Anti-corrosion steel sheet for automobiles with excellent low-temperature chipping resistance and perforation corrosion resistance | |
| JP2000178705A (en) | Hot-dip galvanized steel sheet excellent in darkish discoloration resistance, and its manufacture | |
| KR100286681B1 (en) | Method for manufacturing zero-spangle hot dipped galvanized steel sheet with superior corrosion resistance |