JPH0681112A - Production of titanium sheet and titanium alloy sheet excellent in coating suitability - Google Patents

Abstract

PURPOSE:To improve coating suitability, to prevent galvanic corrosion, and to improve ornamental property, etc., by adhesively coating the surface of a titanium (alloy) sheet with a material excellent in coating adhesion, such as tin and zinc, so that prescribed dispersion index is obtained and then thermally spraying a material different from a base material onto the surface of the above sheet. CONSTITUTION:The surface of a titanium (alloy) sheet is dispersedly and adhesively coated with a material selected from iron, tin, zinc, and ceramics and excellent in coating adhesion by using a physical process so that dispersion index is regulated to >=1000. The dispersion index (Index) is represented by Index =[(the number of <20-mum grains) + (the number of 20- to 50-mum grains)X4+(the number of 50- to 100-mum grains)X25+(the number of >100-mum grains)X100]/(measuring area, 1mmX1mm). Subsequently, a metal or ceramics different from a base material is melted and sprayed and allowed to adhere to the surface of the titanium (alloy) sheet, previously coated dispersedly and adhesively as mentioned above, by which the coating adhesion of the titanium (alloy) sheet can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a titanium plate and a titanium alloy plate having excellent paintability. Hereinafter, in the present invention, the plate is used to include a band,
Hereinafter, these are collectively referred to as a titanium plate.

[0002]

2. Description of the Related Art Since titanium and titanium alloys have excellent corrosion resistance, there is no need for coating corrosion protection. But,
Various improvements have been made from the viewpoint of decorativeness, and an anodic oxidation method and a plating method have been disclosed. For example, Japanese Patent Laid-Open No. 62-1029
No. 7 discloses a barrier type in which titanium or a titanium alloy is subjected to direct current electrolytic treatment in an electrolytic solution containing an electrodeposition resin and an acid capable of forming a barrier type anodic oxide film, with the titanium or titanium alloy as an anode. A method for simultaneously forming an anodized film and an electrodeposition coating film is disclosed. Further, Japanese Patent Laid-Open No. 62-10299 discloses a method for forming a colored film of titanium or a titanium alloy.

Further, as a plating method, Japanese Patent Laid-Open No. 61-8
In Japanese Patent No. 7893, titanium or titanium alloy is finished to a required surface roughness by a mechanical method, and then aluminum is deposited by dry plating to a thickness of 20 to 30 μm, and then aluminum is pretreated by a conventional method to perform copper and gold plating. A surface treatment method is disclosed. In addition, JP-A-6
No. 1-110793 discloses nickel-plated titanium or titanium alloy material, fluorine ions and nickel,
Manufacture of electrolytic nickel plating on titanium or titanium alloy wires in an aqueous solution of an inorganic acid or an inorganic mixed acid containing heavy metal ions such as copper, zinc, iron, etc., which are relatively easy to plate, and then electrolytic nickel plating A method is disclosed.

Further, Japanese Patent Laid-Open No. 63-310993 discloses a method of treating a titanium-based material with a treatment liquid containing a fluoride, then ruthenium strike plating, and then further plating with a noble metal. ing. Further, in JP-A-64-36788, titanium hydride is obtained by immersing a titanium material in a fluoride solution containing ammonium hydrogen fluoride 0.2 to 0.4% and a water-soluble reducing agent for 1 to 4 minutes. A method is disclosed in which (TiH ₂ ) is formed, then nickel plating is performed, and then heat treatment at 200 ° C. or higher is performed, and then a precious metal is plated. Further, in JP-A-3-47991, in a solution having a composition of about 4 to 6% by volume of 70% hydrofluoric acid and 94 to 96% by volume of hydrochloric acid of 36 to 38% concentration,
There is disclosed a method including a step of etching the surface of the composition, and performing a cathode plating of a nickel layer on the etched surface.

However, the above example does not disclose a method for coating a titanium plate. In addition, these electrochemical surface treatment methods applied to a titanium plate or titanium alloy to improve the plating property in strong acid require special equipment and many steps, and the control of the solution must be strict. It is difficult to continuously process the titanium coil because it has to be
The titanium plate or titanium alloy plate manufactured by such a process becomes very expensive and not practical. The conventional anodic oxidation method and plating method improve the decorativeness of the surface by means of chemical reaction such as electrolysis, and solve the original problem that it is difficult to paint like titanium or titanium alloy. Has not been done.

Further, as a technique for improving corrosion resistance and abrasion resistance by melting a metal or ceramics which is completely different from a base material to steel or the like as a base material, thermal spraying is one of surface modification techniques. Although it has been established, the sprayed surface has pores, and when used for structural members such as marine structures and building materials panels, the iron of the base material rusts, solutes on the plate surface and creates a pattern on the panel surface, which is aesthetically pleasing. Unfavorably, in the structure, the original problem that the base material causes crevice corrosion and pitting corrosion is not solved. On the other hand, the corrosion resistance of titanium and titanium alloys is good in the natural world,
There is a drawback that fingerprints are likely to be attached during handling, and although the board surface is dull finished, it is not perfect, and fingerprints and other patterns are attached to the board surface when it is used for building materials, etc. There is a problem.

[0007]

SUMMARY OF THE INVENTION In the present invention, a titanium plate, which has been difficult to coat as described above, is provided with a predetermined dispersion index (Index) of a material of iron, tin, zinc or ceramics having excellent coating adhesion. As a result, a method for producing a titanium plate with improved coating adhesion by closely coating the surface is provided.By using a steel manufacturing facility and continuously treating a large amount in a short time, it is possible to reduce the cost of coating. An object of the present invention is to produce a superior titanium plate and to obtain a titanium plate excellent in corrosion resistance and wear resistance by a method of melting a metal or ceramics completely different from the base material and continuously treating it with a spraying device.

[0008]

The gist of the present invention is that at least one material selected from iron (including impurities), tin, zinc, and ceramics is used as a dispersion index (defined by the formula (1)). (Titanium plate and titanium having excellent coatability, characterized in that a metal or ceramics completely different from the base material is melted and sprayed onto the surface of a titanium or titanium alloy plate that is dispersion-adhered to have an Index value of 1000 or more. Alloy plate manufacturing method.

Dispersion index (Index) = {(number less than 20 μm) + (number greater than 20 μm and less than 50 μm) ×
4+ (number exceeding 50 μm and less than 100 μm) × 25 +
(Number exceeding 100 μm) × 100} / (measured area 1
mm × 1mm) ‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥‥ (1 of this invention, since the titanium plate can be coated according to the present invention, the case where titanium serves as the cathode is prevented from being corroded by dissimilar metals, or during electrical protection. It can be expected to prevent the absorption of hydrogen by titanium and the required anticorrosion current of titanium at the time of electric protection, and the variation of the surface color can be increased in terms of decorativeness.

[0010]

In the present invention, materials such as iron, tin, zinc, and ceramics, which have excellent coating adhesion, are dispersed on the surface of the titanium plate by the dispersion index (Ind).
ex), the coating adhesion was improved by coating 1000 or more. That is, titanium and titanium alloys have excellent corrosion resistance because an inactive film is formed on the surface, but coating is difficult, but iron, tin, and zinc that form an active surface film are therefore difficult to coat. , Ceramics, etc. are physically adhered and coated on the titanium surface by using impact force or vapor deposition to improve the coating adhesion, and a metal or ceramics completely different from the base material is melted and sprayed and welded,
Improved corrosion resistance and wear resistance of titanium plate.

The reason for selecting iron, tin, zinc and ceramics is that iron and tin greatly improve the affinity with the coating film due to the active surface, and zinc and ceramics have the performance of coated titanium. It is to improve. That is, zinc has a sacrificial anodic function and prevents the dispersed and coated iron from being melted out even if a local defect such as a pinhole occurs when it is used in an actual environment after painting. In addition, since ceramics have a very high electric resistance and significantly reduce the conductivity and the electrochemical reaction on the coated surface, the cathodic reaction on the coated titanium surface during the corrosion of dissimilar metals is prevented, and the coated titanium during cathodic protection is used. The ability to prevent loss current flowing into and the ability to prevent hydrogen absorption can be greatly improved.

The dispersion index (Index) is a concept close to the area ratio of the coating material on the surface of the titanium plate. However, the relationship between the ease of measurement, the difference in the dispersion state depending on the particle size and the coating adhesion was investigated. The dispersion index (Index) formula (1) according to the particle size was derived. Dispersion index (Index) is 1000
With respect to the reason for coating as described above, when the dispersion index (Index) of the titanium plate is less than 1000, almost the same coating adhesion as when the titanium plate is coated without a coating is obtained, and therefore the dispersion index (Index) It was set to 1000 or more.

[0013]

Example 1 Titanium and titanium alloy strips having a thickness of 1 mm were subjected to shot blasting with iron having particle diameters of 20 μm, 40 μm and 60 μm, respectively, and an iron dispersion index (Index) = 2.
It was set to 00 to 10,000. 100mm x 100 from this belt
A plate with a size of mm was cut out, zinc-rich primer coating (thickness 20 μm) and aluminum + zinc welding were applied to this, and the coating adhesion was examined by a cross-cut test. Furthermore, after conducting a corrosion acceleration test simulating the sprayed part environment of the marine structure on the coated plate, the adhesion of the coating after being exposed to the corrosive environment was investigated by a cross-cut test. As the corrosion acceleration test conditions, spray 308K (35 ° C) artificial seawater for 4 hours, 33
2 hours at 3K (60 ℃), 323K (50 ℃)
Was exposed to 95% humidity for 2 hours, and these three conditions were continuously repeated for 30 days.

Tables 1 to 6 show the results.
When titanium and titanium alloys were not coated with iron or coated with a dispersion index of less than 1000, they easily peeled off, but the titanium / titanium alloys of the present invention did not peel off and showed high coating adhesion.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Table 3]

[0018]

[Table 4]

[0019]

[Table 5]

[0020]

[Table 6]

[0021]

EXAMPLE 2 Titanium and titanium alloy strips having a thickness of 1 mm were shot-blasted with ceramics having particle diameters of 20 μm, 40 μm and 60 μm, respectively, and the dispersion index (Index) of ceramics was set to 200 to 10,000. A plate having a size of 100 mm × 100 mm was cut out from this strip, and a zinc rich primer coating (thickness 20 μm) and zinc welding were applied to this, and the coating adhesion was examined by a cross-cut test. Furthermore, after conducting a corrosion acceleration test simulating the sprayed part environment of the marine structure on the coated plate, the adhesion of the coating after being exposed to the corrosive environment was investigated by a cross-cut test. As the corrosion acceleration test conditions, 308K (35 ° C) artificial seawater was sprayed for 4 hours, 333K (60 ° C) in a dry state for 2 hours, 323K.
The sample was exposed to a humidity of 95% (50 ° C.) for 2 hours, and these three conditions were continuously repeated for 30 days.

Tables 1 to 6 show the results.
When titanium and titanium alloys were not coated with iron or coated with a dispersion index of less than 1000, they easily peeled off, but the titanium / titanium alloys of the present invention did not peel off and showed high coating adhesion.

[0023]

As described above, according to the present invention, the titanium coil can be coated. Therefore, when titanium serves as a cathode, corrosion of dissimilar metal contact is prevented, or hydrogen absorption of titanium during electric protection is prevented. It can be expected to reduce the required anticorrosion current of titanium at the time of protection, the variation of the surface color will also increase from the viewpoint of decorativeness, and the expansion of the use of titanium in a wide range of fields such as civil engineering and building structures, chemistry, energy plants, automobiles, etc. It is possible and its industrial effect is extremely large.

Front Page Continuation (72) Inventor Koji Honma 20-1 Shintomi, Futtsu City, Chiba Shin Nippon Steel Co., Ltd. Technology Development Division

Claims (2)

[Claims] 1. Dispersion adhesion of at least one material selected from iron (including impurities), tin, zinc, and ceramics so that the dispersion index (Index) defined by the formula (1) is 1000 or more. A method for producing a titanium plate and a titanium alloy plate having excellent coatability, which comprises melting a metal or ceramics completely different from the base material and spraying it on the surface of the coated titanium or titanium alloy plate. Dispersion index (Index) = {(number of particles less than 20 μm) +
(The number exceeding 20 μm and less than 50 μm) × 4 + (50 μ
m + m less than 100 μm) × 25 + (100 μm
> 100} / (measurement area 1mm x 1mm)
‥‥‥‥‥‥‥‥‥‥ (1) 2. A method for producing a titanium plate and a titanium alloy plate which are coated and have excellent coatability.