JPS59140398A - Surface treatment of al or al alloy - Google Patents

Abstract

PURPOSE:To obtain a metallic film having a very high covering rate and superior adhesive strength to an anodic oxide film by applying an electroless plating method as a method for depositing a metal in the micropores in the anodic oxide film of an Al material. CONSTITUTION:Al or an Al alloy is anodically oxidized to form a porous anodic oxide film. Catalytic nuclei for electroless plating are formed in the micropores in the oxide film. For example, a metal acting as the catalytic nuclei is electrochemically deposited in the micropores by a secondary electrolytic coloring technique. After forming the catalytic nuclei, electroless plating is carried out in a bath for depositing Ni-P, Ni-B or the like. Electroless plating starts from the bottoms of the micropores and progresses. The deposited metal fills perfectly the micropores and covers the whole oxide film.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for non-degradable plating of fine pores in anodized aluminum (hereinafter referred to as alumite coating) of Al or Al alloy (hereinafter referred to as Al). .

Conventionally, the so-called secondary coloring technique has been widely used as a method of accumulating metal in the micropores of an alumite film.
Tebru. In this method, Al is subjected to polar oxidation treatment to form a porous alumite film, and then electrolyzed in a bath solution containing gold salt. The precipitated metal produced by the so-called wafer method exists only at the bottom of the pore and above the barrier layer, and the pore is not completely filled with the precipitated metal, which tends to cause reflection failure due to the generation of water-purple gas. Metal surface 5 ffi VOL24, 323
According to VOL 7.22 D, a study is being conducted to fill the entire micropores with precipitated metal, but if the pressure is a
When it becomes more than V.

The metal coverage was low and the result was A. Also, in the same Metal Surface Technology VOL 33, 232, taking these matters into consideration, it is considered that the metal is deposited in the micropores after removing the barrier layer, but it is not possible to remove the barrier layer alone. Not only does it seriously deteriorate the adhesion between the AI material and the alumite film, but it also has the disadvantage of causing galvanic corrosion between the thick lumber A1 and the nail drawer, resulting in extremely poor corrosion resistance. When a Sn-based bath is used as the secondary coloring bath and continued plating is carried out, the entire fine pores are often filled with precipitated gold, and the surface of the anodized aluminum J1 layer is kept as a result of continued plating. However, in the conventional method using such a secondary alumite color, 'A' is visible on the alumite skin.
The adhesion to the precipitated gold parrot is extremely poor.

The reason for this is probably that the deposited metal precipitates in a dendritic manner, and we discovered a method of electroless plating into the fine pores of the alumite film on the surface of the alumite film, and completed this process.

That is, the present invention provides an anodic WAOI treatment of A1 or A1 alloy (2, a first step of forming a porous anodic oxide film).

Electroless plating catalyst (
This is a surface treatment method consisting of a second step of producing alumite, and a third step of electroless plating. l! It has some advantages over other products, such as the ability to obtain a metallic skin scent that has excellent adhesion to the skin.

Next, this invention will be explained in detail. First, as the first 1wI anodic oxidation treatment, the treatment bath for anodizing Al is an inorganic acid bath represented by a normal sulfur bath, a sulfur acid bath represented by oxalic acid, or a mixed bath of these. You may also use equal distances. 1st flow/11: The normally used one-section flow, alternating current, AC/DC claw catch, etc. may be used, and the helical flow recovery method, torrent flow countercurrent method, pulse force flow method, etc. may also be used. The well-known anodic oxidation method A1 may be used.

Next, as the second step, electroless plating #l! A nucleus is generated in the alumite skin @ grm hole. The following three methods can be considered for producing the catalyst 1.

(1) In a method used in so-called wet amorphous body plating, a workpiece that has been subjected to one-place polar oxidation treatment is immersed in a bottled No. 1 product-hydrochloric acid solution, and the no. vague 6
The material to be treated is adsorbed into the holes d, and then the material to be treated is mixed with palladium chloride-chloride solution or nitric acid.

Immerse it in a negative metal salt solution such as a silver solution to remove stiffness.

A method of converting metal salts into prize metals through the reducing action of the L atomic power plant and converting them into metals.

+21 Palladium nitrate, or I Moeki ≦ Iso and 18 Tsuda responsibility now entertainment 4 Ill M Naka Shin Shima "Liquified treatment 43
Immersion of metal salt into alumite skin 1y:4
The iron and secondary holes are in front of you. Then, these pigeons are decomposed using a method such as APA, and the rust is reduced to metal and used as a catalyst nucleus.

f3) A method that utilizes a secondary 4-dissociation color technique to form an alumite skin and then chemically precipitate metals that can become catalyst nuclei in the pores of the alumite film.

Although the method (3) above may be used, the method (3) is particularly preferable. In other words, by electrodepositing on the electrified surface, a catalyst is formed at the bottom of the imitation hole, that is, on the surface of Barriano. Therefore, if electrolytic plating is performed without electrolytic plating, electroless plating will start from the micropores. The metal deposited by electroless plating (referred to as μF plated gold) grows further and finally fills the entire acupuncture hole.If electroless plating is continued further, , plated metal
The plated metal protrudes from the pongee hole, and then the plated metal pierces the entire surface of the alumite film. At this time, the density of the alumite film and the plated metal skin was very thick. 1
801Q: There were no abnormalities as a result of the bending test and thermal shock test. This is probably due to the overall strong anchoring effect.

After slightly generating catalyst nuclei, electroless plating is performed as the third step, and a normal electroless plating bath can be used. For example, Ni-'P, Ni-B.

In addition to the baths that precipitate Ni-00, Co-P, Cu, etc. There is an rrv alloy plating bath. However, since alumite cloth is generally weak against alkalis, a plating bath with a neutral to acidic PHjd is preferred.

Exceeds electroless plating + always performs side hole treatment. Depending on the purpose, plated metal may be alumite skin flIt'! Sometimes the entire surface is pierced, and in such cases there is no need to puncture.

This explanation is based on the method of using non-penetrating plating in the fine pores of alumite skin and depositing black metal on a single body, which has the following advantages and has great industrial effects.

l Electroless plating is used to deposit metal into the pores of the alumite film, so 1-reflection failure does not occur.

2. The barrier layer may be thick, and the adhesion between the alumite film and the material Al is extremely good. Also, there is no problem of galvanic corrosion.

3. The alumite skin is covered with the precipitated metal, reflecting the alumite, and the adhesion with the precipitated metal is very good.

As mentioned above, it is very fundamental in determining moral character.

Furthermore, (1) the surface of the alumite film can be coated with deposited metal by electroless plating and then subjected to normal electroplating, which is better than plating on Al using the conventional Zn substitution method. This is a highly reliable plating method.

t'21 As mentioned above, since a plating film with very good scraping property is obtained, even when soldering is performed on a metal plate, there is no peeling of the film due to heating.

(3) The uniformity of the film thickness, which is one of the characteristics of electroless plating, directly leads to a uniform color tone. Conventional secondary power P! In the case of 6-coloring, in order to achieve a uniform color tone, there are limits to the racking method and input position due to the relationship with the color.

Productivity was a concern, but the so-called sushi racking was D.
This will improve productivity and improve productivity.

(4) Other properties of electroless plating, such as wear resistance and corrosion resistance, are further improved as a synergistic effect with alumite coating.

(5) When non-decomposition-free plating is used as the plating metal, phloem-like magnetic material and 1-1 porcelain material with good 1% property can be produced.

There are many benefits such as:

Next, an actual IM example is shown.
5t) [, 1 was subjected to normal pretreatment including 1υF, and the film thickness was A? A raw alumite skin with pores of 5 to 6 microns was produced. High-gloss alumite skin 1°
1t was 1i.

1 Upgrading fusuma recognition processing order cl〈), n r = 2 0
〜2 ℃　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　/f was deposited.

1 cup 7 temperature 24-26℃ d folding conditions
Break-in time: 1 minute Slow start time: 1 minute A, c! l'i'v constant viewing pressure/plate unraveling time 17Vl 30 seconds Next, electroless plating of N1-P was performed as noted below.

The load was adjusted to 1.0d771/l.

(Here, Nimden 5×: Pure water = 1:5 buoyancy ratio) Bath Stripes 80-85°C PH4, 3-4.5 Treatment time 30 minutes After 30 minutes of treatment, the surface of the alumite film was also N1-f' There are four plating films. Next, N1-P mesh skin; 1.3μ of regular 1m-sized steel mesh with a leveling effect was applied to it,' = [Kikou υ〈141 metal with IUμ, There were no small cracks (0.2μ) between the alumite film surface and the plating surface. ].

The peeling between the plating layers is also good. (Anti @ with good reflexes in fermentation 4)
The mirror was reflected. ) 108L from Meji J) Al plate material (100XI O (JXo,
3t]+P! L shield ifJ treatment? ◆ Porous anodized aluminum with a thickness of J7 to 8μ is reflected under the conditions described in F.

Temperature: 18-20℃ D O: 1,5tyya, (, Time: 20 minutes Perform normal intermediate treatment to make the barrier layer uniform,
-F 粂）'f'' K was used to place 1 piece of A7 into the imitation pore of 1 piece of alumite skin.

Temperature: 23-26°C 1 min. Perform plating.

Bath Composition: BBL nickel (1 coated) was used as an undiluted solution, and the combined load was 1dm71.

Bath temperature: 60 to 65°C PH: 6.8 to 7.0 Treatment time: 60 minutes A black alumite film with a uniform color was obtained after 60 minutes of treatment. When this film was measured with a copying and hardening machine, it was found that
The film showed Hv50υ to 6oo,y and had a 4F quality.

Susev IJ 3 J I S 1 1 U OA14 anti-material (
10 ox l o o'xo, 5t) was subjected to the usual pretreatment, and a porous alumite film of 2 to 3 μm was coated on it under the conditions of r.

Bath temperature 21° to 29°C Electric m=s A CI OOpJ, : Time 1
0 minute lie' (0112, same intermediate treatment, 1 Saki-1 0u (
i? ilj:vI-7b5a; 7] Clear 23-26 °C
Mari Kaijo t'I: Familiar 1 chi exist 1 river 1 minute slow start 1i-il 1 minute AC! Electroless plating of Ji-Sn-P was performed at 13V constant pressure, 13V for 30 seconds, and then electroless plating of Ji-Sn-P.

m Temperature: 85-90'C PH: 4.5 Hours: 30 minutes After 30 minutes of treatment, the surface of the alumite film also became Ni-8n-
P7) Plated gold, 11 ml (faded).Solder to this Ni-8n-P plating film. I4
Good soldering is possible even at home.

Patent developer Pilot Precision Co., Ltd.

Claims (1)

[Claims] 1. A first step of processing AI or A1 alloy to form a porous oxidized film; The second step is to generate catalyst nuclei for non-chemical plating, and then the step (3) for non-chemical plating.
A method for treating A1 or A1 alloy with the following steps: 2J (Al) or Surface treatment method for A1 alloy.