JP3382040B2 - Chemical conversion treatment liquid for titanium or titanium alloy and surface treatment method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical conversion treatment solution for forming a chemical conversion coating film having excellent adhesion on the surface of titanium or a titanium alloy, and a method for surface treatment thereof. A chemical conversion treatment liquid and a surface treatment method thereof, which are applied for a lubrication treatment before molding.

[0002]

2. Description of the Related Art Conventionally, fluoride coatings such as titanium borofluoride and titanium silicofluoride have been known as lubricating chemical conversion coatings for titanium or titanium alloys before cold forming. Tokufair 4
-4397 discloses a fluorine ion of 5 to 40 g / L,
Nitrate ion whose weight ratio to fluorine ion is 0.005 to 0.2 and weight ratio to fluorine ion is 0.0
2 to 0.5 of sulfate ion and Mg, Ca, Mn, F having a weight ratio of 0.02 to 0.5 with respect to the fluorine ion
One or more metal ions selected from e, Co, Ni, Zn and Mo, 0.1 to 3 g / L of an organic chelate compound, 0.1 to 10 g / L of a water-soluble organic polymer compound and 0.01 Disclosed is a chemical conversion treatment liquid having a pH of 1.5 to 5.0 containing one or more compounds selected from a surfactant of 3 to 3 g / L.

However, this chemical conversion treatment liquid cannot form a uniform and good adhesion chemical conversion film on the surface of titanium or its alloy material, which can sufficiently withstand strong working such as cold plastic working. Therefore, there is a defect that seizure easily occurs during cold plastic working of titanium or its alloy material on which a lubricating film is formed.

[0004]

As described above, the conventional chemical conversion treatment liquid cannot form a chemical conversion film having a uniform and good adhesion on the surface of titanium or a titanium alloy, so that a high-strength material, a complicated shape or a high-speed cold working is not formed. When receiving, there is a problem that seizure is likely to occur. It is an object of the present invention to provide a chemical conversion treatment liquid for titanium or titanium alloy and a surface treatment method thereof, which solve these problems.

[0005]

In order to improve the above-mentioned drawbacks, the present inventors have made extensive studies on a chemical conversion treatment solution for titanium or titanium alloy materials and a surface treatment method thereof. As a result, they have found that the above-mentioned conventional problems can be solved by reducing the amount of fluorine ions as compared with the conventional chemical conversion treatment liquid and limiting the alkali metal ions to sodium ions, and completed the present invention.

That is, the present invention provides a chemical conversion treatment solution for titanium or a titanium alloy, comprising (a) fluorine ions 1 to 4.5.
g / L, (b) sulfate ion 0.1 to 5 g / L, (c) sodium ion 1 to 5 g / L, and (d) Mg, Ca,
The chemical conversion treatment, which contains 0.02 to 5 g / L of at least one metal ion selected from Mn, Fe, Co, Ni, Zn, and Mo, and has a pH of 1.5 to 5. Provide liquid.

Further, the present invention provides the chemical conversion treatment liquid for titanium or titanium alloy, wherein (a) fluorine ion is 1 to 4.5 g /
L, (b) sulfate ion 0.1 to 5 g / L, (c) sodium ion 1 to 5 g / L, (d) Mg, Ca, Mn, F
0.02 to 5 g / L of at least one metal ion selected from e, Co, Ni, Zn, and Mo, and 0.1 to 2.0 g / L of (e) organic chelate compound, water-soluble organic polymer compound 0. 1-10 g / L and surfactant 0.01-3
The chemical conversion treatment liquid is characterized by containing at least one compound selected from g / L and having a pH of 1.5 to 5.

Further, according to the present invention, (a) fluorine ion 1 to 4.5 g / L, (b) sulfate ion 0.1 to 5 g / L, and (c) sodium ion 1 on the surface of titanium or titanium alloy.
~ 5 g / L, and (d) Mg, Ca, Mn, Fe, C
a chemical conversion treatment liquid containing 0.02 to 5 g / L of at least one metal ion selected from o, Ni, Zn and Mo, and having a pH of 1.5 to 5 is contacted with the metal surface to give 5 Provided is a surface treatment method for titanium or a titanium alloy, which comprises forming a chemical conversion coating film of about ²⁰ g / m ² .

The structure of the present invention will be described in detail below. The (a) fluorine ion contained in the treatment liquid of the present invention is supplied from a compound arbitrarily selected from fluorine compounds such as hydrofluoric acid, sodium acid fluoride and sodium fluoride, and the addition amount thereof is 1 to 4.5 g / L is preferable. If the amount of fluorine ions is less than 1 g / L, the etching effect on the surface of titanium or a titanium alloy is weak, so that the film chemical conversion is low and the film weight is reduced. On the other hand, 4.5 g / L
Beyond the above, titanium or titanium alloys, especially titanium alloys, the crystal grains of the coating become fine and cover the surface, and the weight of the coating is reduced, which is not sufficient as a base coating when performing strong processing on titanium or titanium alloy materials. Is.

The (b) sulfate ion contained in the treatment liquid of the present invention is supplied from a compound arbitrarily selected from sulfuric acid, a sulfate salt (for example, sodium sulfate etc.), a bisulfate salt and the like. (B) Sulfate ions have the function of preventing intragranular stress corrosion cracking of titanium and titanium alloys and preventing their progress in the presence of halogen ions. (B) The concentration of sulfate ion is preferably 0.1 to 5.0 g / L. (B) If the sulfate ion concentration is less than 0.1 g / L, a sufficient effect of preventing stress corrosion cracking cannot be obtained. Even if it exceeds 5 g / L, no further improvement in performance is observed, which is economically disadvantageous.

The sodium ion (c) contained in the treatment liquid of the present invention is supplied from a compound arbitrarily selected from sodium hydroxide, sodium sulfate, sodium fluoride and the like. (C) The concentration of sodium ion is 1 to 5 g /
L is preferred. (C) Sodium ion concentration is 1 g /
If it is less than L, the amount is not sufficient to form a chemical conversion film. Further, if it exceeds 5 g / L, no improvement in lubrication performance is observed, which is economically disadvantageous. In addition, other alkali metal ions (eg potassium, lithium, etc.) cannot be used because they prevent the formation of the chemical conversion film.

(D) Mg, C contained in the treatment liquid of the present invention
At least one metal ion selected from a, Mn, Fe, Co, Ni, Zn and Mo has the effect of improving the adhesion of the chemical conversion film or making the chemical conversion film dense.
Of these, Mn ions and Zn ions are particularly preferable metal ions. Mn ions have the effect of forming an amorphous compound in the chemical conversion film, making the chemical conversion film dense and enhancing the adhesion of the chemical conversion film. Further, Zn ions form a Zn compound in the upper layer of the chemical conversion film, and react with soap during the subsequent lubrication treatment with sodium soap to form a metallic soap in the surface layer of the chemical conversion film. This metallic soap has good adhesion to the chemical conversion film and shows good lubricity against heavy working. However, if a large amount of Zn ions is added to the chemical conversion treatment solution, the coating weight increases but the adhesion decreases, so an appropriate addition amount is necessary.

The amount of the metal ion (d) added is 0.02.
~ 5 g / L is preferred. The metal ion (d) is usually added as a metal salt. The metal ion concentration of (d) is 0.
If it is less than 02 g / L, sufficient film adhesion and metal deposition amount cannot be obtained. Further, if it exceeds 5 g / L, the precipitation of the titanium compound which is the main component of the chemical conversion film is hindered.

Next, the pH of the chemical conversion treatment liquid of the present invention is 1.5.
Is preferably in the range of 5.0 to 5.0, usually sodium hydroxide,
It is adjusted with sulfuric acid, hydrofluoric acid, etc. When the pH is less than 1.5, the etching action of the titanium material becomes too strong, and even if a film is formed, the chemical conversion film is redissolved and a good film cannot be formed. On the other hand, if the pH exceeds 5, the etching action will be reduced and the film will not be formed sufficiently.

The chemical conversion treatment solution of the present invention further comprises (e) 0.1 to 2.0 g / L of an organic chelate compound, 0.1 to 10 g / L of a water-soluble organic polymer compound, and 0.01% of a surfactant.
At least one compound selected from ˜3 g / L can be added to improve the film performance.

Examples of the organic chelate compound to be added include organic acids such as gluconic acid, citric acid, tartaric acid, succinic acid, tannic acid, nitrilotriacetic acid (NTA) and malic acid, and EDTA. Any of these compounds can be used. You can choose.

The action of the organic chelate compound improves the chemical conversion property by enhancing the effect of the metal ion in consideration of the following phenomena (i), (ii) and (iii), but the organic chelate compound itself adheres to the chemical conversion film. It is considered that it does not directly increase sex. The present inventors have recognized the following phenomenon in the course of research. (I) The organic chelate compound is incorporated into the chemical conversion film. (Ii) On the other hand, even if an organic chelate compound is added to the chemical conversion treatment liquid in which metal ions are not present, the adhesion cannot be improved. (Iii) The proper amount of the organic chelate compound hardly depends on the amount of fluorine ions.

The concentration of the organic chelate compound in the present treatment solution is preferably in the range of 0.1 to 2.0 g / L, and at this concentration, the organometallic chelate compound contributes to the improvement of chemical conversion. If it is less than 0.1 g / L, the effect of improving the chemical conversion can hardly be expected, and if it is added more than 2.0 g / L, the effect is not further improved.

As the water-soluble organic polymer compound,
There is nothing to specify, for example, polyvinyl alcohol,
Gelatin, polyvinylpyrrolidone and the like can be mentioned as preferable ones, and these compounds can be arbitrarily selected. Regarding the water-soluble polymer compound, the same phenomena (i), (ii) and (iii) as those of the organic chelate compound are recognized. That is, (i) the polymer compound is incorporated into the chemical conversion film. (Ii) On the other hand, even if the polymer compound is added to the chemical conversion treatment liquid in which metal ions are not present, the adhesion cannot be improved. (Iii) The proper amount of the polymer compound hardly depends on the fluorine ion amount. The concentration of the polymer compound is in the range of 0.1 to 10 g / L, and contributes to the improvement of the chemical conversion in this range.
If it is less than 0.1 g / L, there is no effect of improving the chemical conversion property of the film, and 10
If it exceeds g / L, on the contrary, it tends to inhibit the chemical conversion.

Finally, the surfactant is an anionic type,
Any of cationic, amphoteric and nonionic compounds can be used, and nonionic and amphoteric compounds are particularly preferable.
The non-ionic such as those of higher alcohol condensate system _{(-O- [CH 2 -CH 2 -O-} ] n -H), higher fatty acid condensates based (-CO-O - [- CH 2 -CH _2- O
-] _N -H), higher fatty acid amide condensate system (-C
_{O · NH - [- CH 2} -CH 2 -O-] n -H) ones,
Higher alkylamine condensates system (-NH - [- CH ₂ -C
H ₂ -O-] _n -H),

[0021]

[Chemical 1]

[0022] things, alkylphenol condensate system (benzene ring _{-O - [- CH 2 -CH 2} -O-] n -H) can also be mentioned ones. Examples of the amphoteric activator include betaine type, glycine type, alanine type and the like, and any of them can be selected and used. Surfactant concentration is 0.01-3g / L
Is preferred. In this range, the surfactant contributes to the improvement of chemical conversion. If it is less than 0.01 g / L, no improvement in chemical conversion is observed, and if it exceeds 3 g / L, further improvement in its effect cannot be expected, and if the chemical conversion treatment liquid contains a high concentration of a surfactant, it will result in that much waste water treatment. This is not preferable because it increases the burden on the user.

The surfactants (ii), (ii)
The phenomenon of i) is recognized. That is, (ii) even if a surfactant is added to the chemical conversion treatment liquid containing no metal ions, the adhesiveness cannot be improved. (Iii) The appropriate amount of surfactant hardly depends on the amount of fluorine ions.

The titanium or titanium alloy surface treatment method of the present invention comprises contacting the treatment liquid of the present invention with the titanium or titanium alloy surface to form a conversion coating of 5 to ²⁰ g / m ^{2 on} the metal surface. It will be.

The method for bringing the chemical conversion treatment liquid of the present invention into contact with the surface of titanium or a titanium alloy is not specified, but a dipping method is particularly preferable. The treatment temperature in the immersion is not particularly limited, but 40 to 80 ° C. is particularly preferable. If the processing temperature is lower than 40 ° C., the etching rate becomes slow and the processing time becomes long, which is economically disadvantageous. Further, if the treatment temperature exceeds 80 ° C., the crystals become finer and the weight of the coating decreases, so that it is not sufficient as a base coating for the strong working of titanium and titanium alloys. When the processing temperature exceeds 80 ° C, the processing tank material (acid resistance, fluorine resistance,
It is necessary to give special consideration to the temperature resistance) and the method of heating the chemical conversion treatment solution. The treatment time largely depends on the treatment temperature and pH, but from 3 to 20 minutes is suitable for practical use.

Under the above treatment conditions, a chemical conversion coating having a coating weight of 5 to 20 g / m ² is formed on the surface of titanium or a titanium alloy. If the coating weight is less than 5 g / m ² , strong plastic working cannot be endured. If it exceeds 20 g / m ² , the adhesiveness to the base material is deteriorated and it cannot withstand the strong plastic working.

After the completion of this treatment, the treated material is subjected to steps such as washing with water and hot water, and then subjected to lubrication treatment. The lubrication treatment is to form a lubricating film on the chemical conversion film by using a lubricant containing molybdenum disulfide, metallic soap, press oil, wax, and resin as an active ingredient.

The chemical conversion coating formed by the present chemical conversion treatment liquid, which is uniform and has excellent adhesion to the base metal, is not peeled off even by strong cold working, and cold workability is improved by holding the lubricating coating. It The reason for this is that the chemical conversion film formed by this chemical conversion treatment liquid has many irregularities suitable for holding lubricant particles and is evenly formed on the surface, so it has the effect of preventing metal-metal contact. it is conceivable that.

The effects of the present invention will be described more specifically below with reference to Examples of the present invention together with Comparative Examples.

【Example】

[Sample material] Titanium alloy material with a diameter of 3 mm and a length of 18 m (T
i3A18V6Cr4Mo4Zr)

[Treatment Step] After annealing, the following steps were performed. Degreasing → Washing → Pickling → Washing → Chemical conversion → Washing → Drying → Wire drawing (lubrication before die) Lubrication is a mixture of 90wt% metal soap powder and 10wt% molybdenum disulfide powder in the lubrication box before die. I went there.

[Treatment Liquid Composition] Table 1 shows compositions of Examples and Comparative Examples. EDTA is used as the organic chelate compound of the compound (e), polyvinyl alcohol (hereinafter referred to as PVA) is used as the water-soluble organic polymer compound, and polyoxyethylene nonylphenol ether (EO 7 mol addition) is used as the surfactant. used.

[Evaluation Method] Table 2 shows the pass schedule for the wire drawing test. The evaluation was made according to the following criteria for the occurrence of image sticking. ◯: No seizure occurred Δ: Slight scratches occurred ×: Seizure occurred (for those with one pass, the second pass was not performed)

In each of Examples 1 to 4, fluorine ions in the chemical conversion treatment solution were 2.0 to 4.1.
g / L, Examples 1 and 2 are cases in which the compound (e) is not added, and Example 3 is EDTA.
Example 4 is a case where PVA and a surfactant were added. The test results are shown in Table 3.

Comparative Example 1 Comparative Example 1 is a case where potassium ion was added instead of sodium ion although the amount of fluorine ion was 4.0 g / L. The test results are shown in Table 3.

Comparative Example 2 Comparative Example 2 is a case in which the amount of fluorine ions was extremely large at 10.0 g / L and the amount of metal ions was extremely large at 8.0 g / L. The test results are shown in Table 3.

Comparative Example 3 In Comparative Example 3, the fluorine ion was 4.0 g / L, the metal ion was not added, and the compound (e) had EDTA of 8.
This is an extremely large case of 0 g / L. The test results are shown in Table 3.

Comparative Example 4 In Comparative Example 4, the fluorine ion is 4.0 g / L,
This is a case in which the compound (e) had an extremely high EDTA content of 7.0 g / L and a surfactant content of 8.0 g / L. The test results are shown in Table 3.

Comparative Example 5 Comparative Example 5 is a case where the amount of fluorine ions is extremely large at 21.5 g / L, which is a case corresponding to Japanese Patent Publication No. 4-4397 of the prior art. The test results are shown in Table 3.

The following can be said from Examples 1 to 4 and Comparative Examples 1 to 4. In each of Examples 1 to 4, the coating weight was 8.0 to 11.
It was 3 g / m ² , and there was no seizure in the 1st and 2nd passes. In the case of adding potassium ions instead of sodium ions in Comparative Example 1, seizure occurred in one pass. In the case of Comparative Example 2 in which the amounts of fluorine ions and metal ions were large, slight scratches occurred in one pass, and burn-in occurred in two passes. In the case where the metal ion of Comparative Example 3 was not added and the addition amount of the compound (e) was much larger than that of the example, seizure occurred in the second pass. In the case where the addition amount of the compound (e) in Comparative Example 4 was much larger than that in the Examples and the pH was less than 1.5, the burn-in occurred in the second pass. In the case of Japanese Patent Publication No. 4397 of the prior art of Comparative Example 5, seizure occurred in the second pass.

[0040]

EFFECTS OF THE INVENTION When a titanium or titanium alloy material is treated using the chemical conversion treatment solution and the surface treatment method of the present invention, a chemical conversion film having a uniform and excellent adhesion is formed on the surface of the material.
The chemical conversion coating exhibits excellent cold workability without seizure during cold working together with the lubrication treatment performed in the subsequent step.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

[Table 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsufumi Hayashi 1-15-1 Nihonbashi, Chuo-ku, Tokyo Nihon Parkerizing Co., Ltd. (72) Inventor Kazuo Matsubashi 7-5-1, Higashi Narashino, Narashino, Chiba Prefecture Suzuki Metal Industry Co., Ltd. (72) Inventor Tadayoshi Nakazawa 7-5-1, Higashi Narashino, Narashino City, Chiba Prefecture Suzuki Metal Industry Co., Ltd. (72) Ino Morii, 7-5-1, Higashi Narashino, Narashino City, Chiba Suzuki Metal Co., Ltd. Kogyo Co., Ltd. (56) Reference JP-A-63-286585 (JP, A) JP-A-63-256435 (JP, A) JP-A-62-67181 (JP, A) JP-B-44-28967 (JP , B1) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C23C 22/00-22/86 C23G 1/00-5/06

Claims (3)

(57) [Claims] 1. A chemical conversion treatment solution for titanium or titanium alloy, comprising: (a) fluorine ion 1 to 4.5 g / L, (b) sulfate ion 0.1 to 5 g / L, (c) sodium ion 1 to 5 g / L. L, and (d) at least one metal ion selected from Mg, Ca, Mn, Fe, Co, Ni, Zn and Mo 0.02
The said chemical conversion treatment liquid containing 0.5-5 g / L and having pH of 1.5-5. 2. A chemical conversion treatment solution for titanium or titanium alloy, comprising: (a) fluorine ion 1 to 4.5 g / L, (b) sulfate ion 0.1 to 5 g / L, (c) sodium ion 1 to 5 g / L. L, (d) at least one metal ion selected from Mg, Ca, Mn, Fe, Co, Ni, Zn and Mo 0.02
To 5 g / L and (e) at least one selected from 0.1 to 2.0 g / L of organic chelate compound, 0.1 to 10 g / L of water-soluble organic polymer compound and 0.01 to 3 g / L of surfactant. The chemical conversion treatment liquid containing a compound of a species and having a pH of 1.5 to 5. 3. On the surface of titanium or titanium alloy, (a) fluorine ion 1 to 4.5 g / L, (b) sulfate ion 0.1 to 5 g / L, (c) sodium ion 1 to 5 g / L, and (D) 0.02 of at least one metal ion selected from Mg, Ca, Mn, Fe, Co, Ni, Zn, and Mo
Titanium or titanium containing 5 to 5 g / L and having a pH of 1.5 to 5 in contact therewith to form a chemical conversion coating of 5 to ²⁰ g / m ^{2 on} the metal surface. Alloy surface treatment method.