JP2814045B2 - Plated aluminum plate with excellent sliding characteristics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plated aluminum sheet, and more particularly to a zinc-based alloy-plated aluminum sheet having excellent sliding properties and applicable to various uses, for example, an aluminum sheet for automobiles. is there.
In the present invention, the term “aluminum plate” refers to a meaning including an aluminum plate and an aluminum alloy plate.

[0002]

2. Description of the Related Art Conventionally, automobile manufacturers have used steel sheets for automobile bodies. Here, the steel sheet refers to a normal steel sheet, a high-tensile steel sheet, a zinc-based electroplated steel sheet or a zinc-based hot-dip coated steel sheet. Of these, surface-treated steel sheets such as galvanized steel sheets have excellent corrosion resistance,
In particular, it is actively used for parts requiring corrosion resistance, such as fenders and door panels. On the other hand, recently, there has been a demand for using an aluminum plate for an automobile body mainly for the purpose of improving the fuel efficiency of the automobile and reducing the weight of the vehicle body for improving the power performance. However, it is rare that the entire body of an automobile is made of an aluminum plate, and in general, a part of the body is replaced by a steel plate with an aluminum plate.

Here, in a car production line,
Since aluminum sheets are mostly used in automobile production lines established with existing steel sheets, their material properties must be equal to or better than those of steel sheets and can be applied to existing automobile production lines themselves. is important. Attempts have been made to make the properties of an aluminum plate required at the time of assembling an automobile body close to those of a steel plate with respect to the zinc phosphate treatability as a pretreatment for coating.

[0004] For example, Japanese Patent Application Laid-Open Nos. 61-157593, 4-17677, and 4-1777
No. 8, JP-A-4-17679, JP-A-4-1
No. 7,680, proposes a method of applying zinc plating to an aluminum plate as a method for improving the zinc phosphate treatability of the aluminum plate. However, as in the present invention, there is no one in which the plating is formed in a granular form to significantly improve the sliding characteristics of the aluminum plate.

[0005]

As described above, in order to use an aluminum plate in a production line of an existing automobile, the material properties of the aluminum plate must be equal to or higher than that of the steel plate. However, the press formability of an actual aluminum plate is considerably inferior to that of a steel plate. For this reason, various materials have been developed in order to improve the press formability. Apart from this, studies have been made on the aspect of improving the lubricity. Accordingly, the present invention provides an aluminum plate that solves such a problem, that is, an aluminum plate having excellent sliding characteristics during press forming.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies on the development of a plating method which is low in cost and has excellent sliding characteristics in order to solve these problems. The present invention has been made by finding that excellent sliding characteristics can be obtained by forming plating. That is, the gist of the present invention is as follows: (1) In an aluminum plate plated with a metal or an alloy which can be electrodeposited from an aqueous solution, the shape of the plating is granular, and the coverage area of the particles is 300 (μ).
m) ² or less, the coverage of the surface of the aluminum plate with the grains having a height / width ratio of height / width ≧ 1/20 is 5 or less.
A plated aluminum plate excellent in sliding characteristics, characterized in that the content is set to 70%.

(2) In an aluminum plate coated with a zinc-based alloy, the shape of the zinc-based alloy plating is made granular, the coverage area of the grains is 300 (μm) ² or less, and the ratio of the height to the width of the grains is high. A zinc-based alloy-plated aluminum plate having excellent sliding characteristics, wherein the coverage of the surface of the aluminum plate with grains having a form of width / 1/20 is set to 5 to 70%.

(3) In a zinc-based alloy-plated aluminum plate, the shape of the zinc-based alloy plating is granular, the coverage area of the grains is 100 (μm) ² or less, and the ratio of the height to the width of the grains is high. A zinc-based alloy-plated aluminum plate having excellent sliding characteristics, wherein the coverage of the surface of the aluminum plate with grains having a form of / width ≧ 1/10 is 5 to 70%.

[0009]

The present invention will be described below in detail. In the present invention, the effect of the plating is to improve the sliding characteristics. In the present invention, the plating is formed in a granular form on the surface of the aluminum plate, and the coating area of the particles is 300 (μ).
m) ² or less, 5 to 7 parts of the surface of the aluminum plate by the particles having a form in which the ratio of the height and width of the particles is height / width ≧ 1/20.
It is essential that 0% is coated. In the present invention, the term “grain” refers to a grain having a thickness of 0.01 μm or more in which zinc-based alloy grains are attached in a convex shape to the surface of an aluminum plate after plating. Further, the formation of plating grains widely covers both cases described below. (1) Some are independent, and some are in contact with each other, and the plating grains after plating are distributed on the surface of the aluminum plate. (2) The extremely thin plating layer of less than 0.01 μm A state in which the plated layer is distributed after plating so that the protrusions are locally present at the top.

In the present invention, the coating area of the plating grains means the area of the plating grains projected perpendicular to the surface of the aluminum plate. 300 (μm) ²
The reason for limiting to the following is that, when the covering area is large, the tendency of individual grains to be connected increases, and granular plating excellent in sliding characteristics cannot be obtained. The reason for setting the range to 100 (μm) ² or less as a more preferable range is that when the coating area is 100 (μm) ² or less, the number of particles per unit area increases, and the effect of improving the sliding characteristics by the particles is larger. It is because it becomes.

Next, in the present invention, the grain height and grain width are projected perpendicularly to the maximum grain height and the grain surface of the aluminum plate in the portion where the plating thickness is 0.01 μm or more. Refers to the maximum length of the part. The reason for limiting the ratio of the height and width of the plating grains to height / width ≧ 1/20 is that
If the ratio of height to width is less than 1/20, the effect of improving the sliding characteristics is insufficient. The reason why the height / width ≧ 1/10 is more preferable is that when the ratio of height to width is 1/10 or more, the unevenness becomes clear and the effect of improving the sliding characteristics by the particles becomes greater. . Although the upper limit of the ratio of height to width is not particularly defined, the range that can be easily produced industrially is 2 or less.

Next, the coverage of the plate surface with the particles is the ratio of the area covered with the particles to the surface area of the aluminum plate. The reason why the coverage of the aluminum plate surface by the plating grains is limited to 5 to 70% is that if it is less than 5%, the coverage is too small to obtain the effect of adhering the plating. This is because the tendency of the individual grains to be connected increases, and it is not possible to obtain granular plating having excellent sliding characteristics.

In the present invention, the reason why the sliding characteristics are improved by making the plating granular is not clearly understood, but the following may be considered as the reason. (1) By making the plating granular, the contact area between the press die and the plated aluminum plate is reduced. (2) By making the plating granular, a pool of lubricating oil is formed between the plating grains, and the coefficient of friction is reduced.

The metal or alloy for plating specified in the present invention will be described below. First, metal or alloy plating that can be electrodeposited from an aqueous solution is defined as Zn, Fe, N
Metals such as i, Sn, Cr, Co, Mn, Pb, Cu, and Ag, or alloys composed of two or more of these metals. Zinc-based alloy plating refers to Fe, Ni, Co,
It refers to zinc-based alloy plating containing one or more alloy elements such as Cr and Mn, and the alloy element content is 1 to 90%. The reason for limiting the plated metal or alloy in the present invention to the above is that these metals are harder and have less deformation than Al, so that when press forming is performed, compared to an aluminum plate mechanically provided with similar irregularities, The board reduces the increase in contact area,
This is because the sliding characteristics are improved.

Hereinafter, the present invention will be described specifically with reference to examples.

【Example】

Example 1 First, a rolled plate of JIS5182-O material was prepared as a material, and granular electroplating as shown in Table 1 was performed thereon.
The granular plating was obtained by electrochemically anodizing the surface of the aluminum alloy plate and then performing electroplating using a plating bath containing the respective metal ions. The evaluation test was a flat plate pull-out test. The test conditions are shown below. Specimen dimensions: 1.0 mm × 30 mm × 300 mm Pressing force: 450 kgf Pulling speed: 200 mm / min Tool contact area: 900 mm ² (30 mm × 30 mm) The results are as shown in Table 1, and all of the materials of the present invention are cold rolled A coefficient of friction equivalent to that of a steel plate was obtained, and the sliding characteristics were improved compared to an aluminum plate that was not plated.

[0016]

[Table 1]

Example 2 First, a rolled plate of JIS 5182-O material was prepared as a material, and granular Zn—Fe (10%) as shown in Table 1 was added to the rolled plate.
Electric alloy plating was performed. The granular plating was obtained by electrochemically anodizing the surface of the aluminum alloy plate and then performing electroplating using a sulfuric acid bath containing Zn ²⁺ and Fe ²⁺ . The evaluation test was performed under the same conditions as in Example 1. The results are as shown in Table 2, wherein the coverage area of the grains was 300 (μm) ² or less, and the ratio of the height to the width of the grains was height / height.
The material of the present invention, in which the coverage of the surface of the aluminum plate with the particles having a width of ≥ 1/20, is 5 to 70%, has improved sliding characteristics over the aluminum plate without plating. Also,
The material of the present invention in which the coverage of the aluminum plate surface is 5 to 70% by the grains having a form in which the coverage area of the grains is 100 (μm) ² or less and the ratio of the height to the width of the grains is height / width ≧ 1/10. Is
In each case, a coefficient of friction equivalent to that of a cold-rolled steel sheet was obtained, and the sliding characteristics were improved as compared with an aluminum plate that was not plated.

[0018]

[Table 2]

Example 3 First, an aluminum alloy rolled plate shown in Table 3 was prepared as a raw material, and a granular Zn—Fe (10%) electric alloy plating was performed on the plate. In the granular plating, the surface of the aluminum alloy plate is electrochemically ^anodized, and then Zn ²⁺ and F 2
It was obtained by performing electroplating using a sulfuric acid bath containing e ²⁺ . The evaluation test was performed under the same conditions as in Example 1. The results are as shown in Table 3. The materials of the present invention all exhibited the same coefficient of friction as the cold-rolled steel sheet, and the sliding properties were improved as compared with the aluminum sheet without plating.

[0020]

[Table 3]

[0021]

According to the present invention, a plated aluminum plate having excellent sliding characteristics can be manufactured by attaching the plating in a granular form, and its industrial value is very large.

Continuation of the front page (72) Inventor Akira Takahashi 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (56) References JP-A-5-44080 (JP, A) JP-A-4 -32598 (JP, A) JP-A-5-287588 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C25D 3/00-7/12

Claims (3)

(57) [Claims] 1. An aluminum plate plated with a metal or an alloy which can be electrodeposited from an aqueous solution, wherein the plating has a granular shape and the grain coverage is 30%.
0 (μm) ² or less, the ratio of the height and width of the grains is height / width ≧ 1 /
20. A plated aluminum plate having excellent sliding characteristics, wherein the coverage of the surface of the aluminum plate with the grains having the twentieth form is 5 to 70%. 2. An aluminum plate on which zinc-based alloy plating has been applied, wherein the zinc-based alloy plating has a granular shape,
It is characterized in that the coverage of the aluminum plate surface with the grains having a form in which the coverage area of the grains is 300 (μm) ² or less, and the height / width ratio of the grains is height / width ≧ 1/20 is 5 to 70%. Zinc-based alloy-plated aluminum plate with excellent sliding characteristics. 3. An aluminum plate on which zinc-based alloy plating has been applied, wherein the zinc-based alloy plating has a granular shape,
The coverage of the aluminum plate surface is 5 to 70% by the grains having a form in which the coverage area of the grains is 100 (μm) ² or less and the height / width ratio of the grains is height / width ≧ 1/10. Zinc-based alloy-plated aluminum plate with excellent sliding characteristics.