JPS63247332A - Zinc alloy for iridescent colored galvanization and its using method - Google Patents

Abstract

PURPOSE:To form an iridescent colored galvanized film in which gold, purple, blue and green colors are mingled by immersing a member to be galvanized in specific ratios of Zn-Mn of Zn-Mn-Cu molten alloy galvanizing bath, galvanizing the same and subjecting said member to a hot-water cooling treatment. CONSTITUTION:The iron steel member to be galvanized subjected to a descaling treatment by degreasing, cleaning and pickling is immersed in the galvanizing bath of 450-550 deg.C in which 0.1-0.8wt.% Mn is added and melted, or including Mn, 0.05-1.0wt.% Cu is added and melted thereto to form a galvanized film by the molten Zn of the surface of the member, and after that, is applied to the hot-water cooling in which the member is immersed in hot water of 40-60 deg.C for 3-30sec. In this way, the iridescent colored galvanized film in which gold, purple, blue and green colors are mingled can be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a coloring hot-dip galvanizing technology for the surface of steel materials, and in particular gold, purple, blue, and green colors not found in conventional coloring. The present invention relates to a method of forming an iridescent colored hot-dip galvanized coating containing a mixture of the above and the like, and a zinc alloy therefor.

Hot-dip galvanized steel materials, which are plated using hot-dip zinc, are widely used for corrosion-resistant purposes in a wide range of fields, including components and facilities in sectors such as architecture, civil engineering, agriculture, fisheries, chemical plants, and power transmission. .

By the way, in recent years, steel towers, lighting poles, guardrails,
For facilities such as temporary structures for various works and exhibitions, exterior panels, etc., we use colored hot-dip galvanizing, which has a more aesthetically pleasing color that matches the surrounding environment, rather than conventional hot-dip galvanized materials that exhibit a metallic color. It has become a trap so that the material is requested. As aesthetic awareness increases, demand for colored hot-dip galvanized materials is expected to increase in the future in a wide range of fields including architecture, civil engineering, plants, power transmission, transportation, agriculture, fisheries, and more.

The conventional coloring method for hot-dip galvanized rA is to color the plated steel by painting, but since Zn in the plating film of hot-dip galvanized steel is active, the oil component of the paint The fatty acids gradually decompose with alkaline to form zinc soap. Therefore,
There is a drawback that the paint film used for coloring does not adhere to the surface of the plating film and peels off.

Therefore, in order to prevent such defects, conventionally, steel is plated with molten zinc, and the plated steel obtained is then exposed to the atmosphere for 1 to 3 weeks to further coat the plated film with Zn(OH). It was necessary to perform the complicated operations of forming corrosion products such as ZnO1ZnCO3 and ZnC1z, then cleaning the surface of the plated steel, and then applying a coating for coloring. Apart from the painting method, a coloring method is known that utilizes the coloring effect of an oxide film during hot-dip galvanizing. For example, Tokuko Sho 46-4200
No. 7 discloses a coloring method using a hot-dip galvanizing bath to which one or more of titanium, manganese, vanadium, etc. is added. However, it was found that the color tone of the colored hot-dip galvanizing obtained according to the technique disclosed herein was generally very pale, the color quickly faded over time, and the coating was likely to peel off. It was not possible to accurately control the color development of the desired color, and the tones often became blurred.

Under these circumstances, the applicant of the present application has worked to establish a colored hot-dip galvanizing technology that produces vivid colors by increasing the amount of additives, and has achieved many results. Nowadays, it is possible to freely produce a wide variety of hues such as golden yellow, purple, blue, yellow, dark red, and green by combining component control and plating and post-processing conditions. If the conventional hue can be made richer and the aesthetics and decoration, as well as the artistry, can be further improved, the scope of colored hot-dip galvanizing will be further expanded. For example, various exhibition halls,
Highly decorative materials would be appropriate for temporary pedestals and exterior panels at amusement parks. It is thought that decorativeness will become important in the future for guardrails and civil engineering and construction sites around the city.

SUMMARY OF THE INVENTION In view of these issues, the present inventors went beyond simply coloring the conventional hot-dip galvanized materials with a metallic color, and developed an epoch-making color development that breaks the conventional image of exterior color.
We conceived of an iridescent colored plating that is a mixture of gold, purple, blue, and green, and succeeded in creating that color.

As a result of research into a method for forming a zinc alloy and plating suitable for the simultaneous development of specific hues necessary for iridescent color development, the present invention has developed the following: 1) 0.1 to 0.8 vt%Mn or (L 1
An iridescent-colored zinc alloy for hot-dip galvanizing containing a mixture of gold, purple, blue, green, etc., containing ~0.8 wt%Mn and α05~tOvrt%Co, and the remainder consisting of Zn and inevitable impurities, and 2) (L1~0.8wt%Mn or α1~0.8w
Hot-dip plating is applied to a steel material at a bath temperature of 450 to 550°C using a zinc alloy plating bath containing t%Mn and α05 to tOwt%Cu, with the remainder consisting of Zn and unavoidable impurities. To provide a method for forming an iridescent colored hot-dip galvanized plating in which gold, purple, blue, green, etc. are mixed, which is characterized by cooling.

Hot-dip zinc alloy plating is carried out by dissolving a zinc alloy in a plating bath and immersing the steel material to be plated therein. To obtain an iridescent colored plating, it is necessary to perform plating under specific conditions using a molten zinc alloy bath having a specific composition range.

Zinc alloys are prepared by adding certain alloying additives to zinc bullion. In the present invention, the zinc ingot used for the molten zinc alloy is mainly distilled zinc ingot (purity 9a, 5% or more) specified by JIS H2107g.
Examples include the purest zinc ingot (9999% purity) and special zinc ingot.The impurities unavoidably contained in these zinc ingots are, for example, Pbt2vt% in one type of distilled zinc ingot.
Hereinafter, Cd (L1vt% or less, F@CLO20wt% or less), but in the present invention, it is preferable to use a zinc base metal in which the total content of these impurities is less than t5vt%.

According to the present invention, the zinc ingot K (1) 01~α8 t%, preferably 12~a8w
t%M! L or (2) α1 to 8wt%, preferably α2 to α8w
A molten zinc alloy bath containing tOwt% Mn and α05 to tOwt% Cu − is used.

If the Mn content in the plating bath is less than 11 wt%, the oxide film is not formed yet, resulting in a pale color tone and a 0.0% Mn content in the plating bath.
If it exceeds 8wt%, the hue will be 1! It becomes difficult to align the plated material, and the wettability of the plating material worsens. Mn content is α2vt
% or more, the iridescent color will be more stable and easier to develop. α0
Addition of 5 to 1.0 wt% Cu improves the dripping of the plating solution and is effective in preventing peeling of the oxide film.

Hot-dip plating is performed using the above-described hot-dip zinc alloy bath at a bath temperature of 450 to 550°C. The soaking time is about 1 to 3 minutes. After dipping, the plated material is cooled in hot water. Hot water cooling is 40
This is done by immersion in warm water at ~60°C for 3-30 seconds. If the composition and processing conditions are outside the above specified ranges, the desired iridescent coloring cannot be obtained.

If the material to be plated was too thin, it was difficult to obtain an iridescent color, probably because the cooling rate was faster. 16℃ 1m
It is preferable to use a material to be plated having a thickness greater than or equal to the above thickness.

Before plating, the material to be plated is subjected to conventional pretreatment. That is, the material to be plated is degreased using an alkaline bath, scale removed by pickling, etc., and then coated with, for example, ZnCl2.
-KF-based bath solution Flux treatment is carried out by short immersion in a flux solution such as ZnCl2-NH4C1 solution.

With these simple operations, an iridescent colored plating with a mixture of gold, purple, blue, and green can be obtained. This plating material also maintains corrosion resistance and can be widely used in fields that require good appearance and corrosion resistance.

Example Width 50ssX Length 100tllX Thickness 16~&0IEl
Place the 5S411'J board with dimensions B in an alkaline bath at 80°C.
After immersing for 0 minutes to degrease, wash with hot water, then 10%
The scale was removed by immersing it in a hydrochloric acid solution for 300 minutes at room temperature. Next, after washing this steel plate with hot water, 35% ZnC1g-NH,C
1 solution at 60° C. for 1 minute to perform flux treatment. The thus pretreated steel plates were plated by immersing them in a plating bath having a composition as shown in Table 1 at a temperature of 450 to 550° C. for 1 minute, and then cooling with hot water. Hot water cooling is
This was carried out by immersion in 40°C warm water for 5 seconds.

The results are shown in Table 1.

Table 1 Peeling of oxide film; No O generation, X generation, sapping removal;
O Good The material is expected to have applications in a wide range of fields and in areas where it has not been used before.

Claims (1)

[Claims] 1) 0.1 to 0.8 wt% Mn or 0.1 to 0.8
An iridescent colored zinc alloy for hot-dip galvanizing containing a mixture of gold, purple, blue, green, etc., containing wt% Mn and 0.05 to 1.0 wt% Cu, with the remainder consisting of Zn and inevitable impurities. 2) 0.1-0.8wt%Mn or 0.1-0.8
Using a zinc alloy plating bath containing wt% Mn and 0.05 to 1.0 wt% Cu, with the balance consisting of Zn and unavoidable impurities, hot-dip plating is applied to steel materials at a bath temperature of 450 to 550°C. A method for forming an iridescent colored hot-dip galvanized plating with a mixture of gold, purple, blue, green, etc., which is characterized by cooling with hot water.