JP2001226797A - Aluminum alloy for extruded shape material and extruded shape material product for building using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum alloy capable of forming a satin surface of a light gray color by alkali etching treatment and anodic oxidation treatment by the conventional methods. SOLUTION: An aluminum alloy having an alloy composition for extrusion molding in which Mg, Si, Fe, or the like are added and incorporated and moreover containing Sn of 0.3 to 0.8 wt.% is prepared, and the extruded shape material thereof is subjected to aging treatment, is thereafter subjected to the conventional alkali etching treatment to form a fine and uniform satin surface and is subjected to anodic oxidation treatment to enable the developing of a light gray color by the diffused reflection and refraction of light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an aluminum alloy,
In particular, the present invention relates to an extruded aluminum material suitable for an extruded profile and an extruded profile product for a building using the same.

[0002]

2. Description of the Related Art As an aluminum alloy for this type of extruded profile,
Those specified in various JIS standards are used. For example, alloy number 6063 (alloy code: A6063S) is used for construction purposes, and the extruded material using this is age-hardened by aging treatment, and then the surface is hardened. After being processed, it is made into various architectural extruded material such as aluminum sash and siding.

[0003] At this time, the extruded profile after extrusion molding has a die line formed by a die used for extrusion, and a flaw appears thereafter. Therefore, as a pre-process of surface treatment, the extruded profile is removed so as to eliminate it. A process for making the surface a matt surface is performed.

[0004] Generally, as this kind of satin finish, methods such as mechanical processing, acid etching, alkali etching, and electrolytic etching are known.

There are sand blasting, liquid homing, etc. as mechanical processing. In this case, a matte surface can be obtained relatively easily, but there is a drawback that it cannot be applied to a complicated shape such as an extruded shape for building. is there.

There is a method of using sulfuric acid, phosphoric acid, nitric acid or the like as the acid etching. In this case, to obtain a matte surface, particularly a fine matte surface, a mixed bath of hydrofluoric acid or fluoride, and further, hydrochloric acid or chloride. It is difficult to avoid the incorporation of halides into the processing tanks such as anodic oxidation and secondary electrolysis in the post-process, which causes poor surface treatment such as surface roughness. There are drawbacks such as an increase in management and processing costs.

There is a method of adding a metal salt to caustic alkali as alkali etching. In this case, however, the matte treatment effect is low, and the luster gloss peculiar to the aluminum material remains. There is a drawback that it cannot be erased and a matte surface which is preferable as a high-quality product cannot be obtained.

In the case of electrolytic etching, it is possible to obtain a relatively preferable matte surface, but the process becomes complicated due to the necessity of using an electrolytic bath and the necessity of processing at a high current density, and the like. There is a drawback that it is not always suitable for industrial use because it causes an increase in cost.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances.
Firstly, it is suitable for industrial use in which an extruded material having a light gray surface can be obtained as easily and reliably as possible in a general surface treatment step, with a fine and uniform matte surface, which is preferable as a high quality product. Second, to provide a suitable extruded aluminum alloy for extruded shapes, and secondly, to have a fine and uniform pear surface with a light gray surface or to color it, which is preferable as the above high quality product using this aluminum alloy. An object of the present invention is to provide an extruded architectural product used as a foundation.

[0010]

Means for Solving the Problems As a result of intensive studies conducted in accordance with the first problem, an aluminum alloy has a basic alloy composition for use as an extruded material by extrusion molding, while it has a small amount of aluminum alloy. The aluminum alloy is extruded and then subjected to a conventional alkali etching process using an extruded shape material that has been subjected to an aging treatment to obtain a fine and uniform matte surface. In addition, by applying anodizing treatment to this, a light gray color can be obtained, and the gloss and die line peculiar to the aluminum alloy are completely eliminated, and it is a preferable extruded shape material as a high quality product with excellent aesthetic feeling. It has been found that it is possible to carry out the present invention. That is, the invention according to claim 1 is applied to an aged extruded material by alkali etching and anodic oxidation. A aluminum alloy extrusion profile used as a light gray surface of the satin finished by,
3. The extruded aluminum alloy according to claim 2, wherein the aluminum alloy has a predetermined alloy composition for the extruded profile and further contains a small amount of Sn in addition to the alloy composition. The present invention further provides the Sn content in addition to the above.
In order to obtain a fine uniform pear surface and a preferable light gray color, the content of said trace amount of tin is set to 0.3 to 0.8 wt%. The aluminum alloy for an extruded section according to claim 1 is an aluminum alloy for an extruded section, and the invention according to claim 3 further comprises, in addition to the above, an aluminum alloy for the extruded section so as to make the alloy composition suitable for the extruded section. The predetermined alloy composition for the section is set to 0.4 to 0.
9 wt%, 0.2 to 0.6 wt% of Si, and 0.1 wt% of Fe.
The aluminum alloy for an extruded section according to claim 1 or 2, characterized in that the composition contains 1 to 0.4 wt% and the balance is Al and unavoidable impurities. According to the invention of claim 4, the extruded material obtained by extruding the aluminum alloy for an extruded material according to claim 1, 2, or 3 and then subjecting to aging treatment is subjected to alkali etching treatment and anodic oxidation. An extruded architectural shaped product characterized by forming a matte light gray surface by the treatment, extruding the invention of claim 5 and extruding the aluminum alloy for extruded shape of claim 1, 2, or 3 Extrusion for architectural use, characterized in that the extruded material, which has been molded and then subjected to aging treatment, is made into a light gray surface of satin by alkali etching and anodic oxidation, and is colored by secondary electrolytic treatment. Profile products And, as the gist of the invention these respectively, it is obtained by the above first or second problem solving means.

The addition and inclusion of Sn in an aluminum alloy is as follows.
Since the electrochemical properties of aluminum alloys are considered to be low, they can hinder the electrochemical treatment in the surface treatment such as anodic oxidation treatment, secondary electrolytic treatment, and electrodeposition treatment of the extruded material. It should be a trace amount of 1 wt% or less, but if the added content is less than 0.3 wt%,
The effect of the matte finish in the alkali etching treatment is small, and the fine uniformity of the matte finish tends to be impaired. On the other hand, if it exceeds 0.8 wt%, the extrudability is impaired and the surface is pitted by the alkali etching treatment, resulting in fine uniformity. In order to cause a tendency to impair the proper appearance and a tendency to impair the corrosion resistance after anodic oxidation, the content of the additive should be not less than 0.3 wt% and not more than 0.8 wt%. Is effective in obtaining
Looking at this additive content from the light gray coloration,
If the amount is less than 0.3 wt%, it becomes difficult to secure a coloring effect,
If the amount is less than 0.4 wt%, the degree of gray coloring tends to slightly decrease. On the other hand, if the amount exceeds 0.8 wt%, the gray color tends to be too dark, which is not always preferable in a product. Occurs. For this reason, S
The content of n is generally in the range of 0.3 wt% to 0.8 wt%.
Although it is preferable to set the amount to 0.4% by weight, it is particularly preferable to set the amount to 0.4% to 0.8% by weight in consideration of the degree of light gray color development.

The composition of the aluminum alloy for the extruded profile is determined in consideration of the extrudability, the surface roughness during extrusion, the profile strength and surface treatment properties according to the use as the extruded profile, and Mg, Si, F
e and the other metals can be appropriately added and contained, but in the present invention, Mg, S
It is preferable that i and Fe are added and the remainder is composed of Al and unavoidable impurities, so that the printing can be performed with the properties to be considered as the alloy composition. If the content of Mg is less than 0.4 wt% at this time, the effect of aging treatment due to the formation of the compound Mg ₂ Si with Si is not sufficient, and the strength of the extruded material tends to decrease, resulting in 0.9 wt%. Exceeding the above range tends to impair the extrudability and cause the surface of the extruded profile to become rough.
It is preferable that the content be not less than t% and not more than 0.9 wt%.

[0013] Since the addition of Sn suppresses the properties of Sn, which makes the aluminum alloy electrochemically base, and has the effect of enabling the surface treatment of the extruded material to be carried out favorably. However, if the content is less than 0.2 wt%, the aging effect is not sufficient, and the strength of the extruded material tends to decrease. %, The extrudability is similarly impaired and the surface of the extruded profile tends to be roughened.
It is preferable that the content is not less than wt% and not more than 0.6 wt%.

Fe has a strong tendency to lower the mechanical strength and the corrosion resistance of the aluminum alloy, and has an additive content of 0.1%.
When the content exceeds 4 wt%, the tendency becomes remarkable, and the extrudability is impaired. When the content exceeds 0.3 wt%, the tendency is observed. Since it has the effect of relieving casting cracks as much as possible and improving the casting speed, the content of Fe added should be 0.1 wt% or more and 0.4 wt% or more.
%, More preferably 0.1 wt% or more and 0.3 wt% or less in consideration of the casting efficiency of the aluminum alloy.

The extruded aluminum alloy containing the above-mentioned Sn is formed into an extruded shape by extrusion molding, and after aging treatment, for example, as shown in FIG. The extruded material that has been aged at this time can have a matte light gray surface by alkali etching and anodizing. Applying coating treatments such as electrodeposition coating, dip coating, spray coating, etc., and applying the same coating treatment as the secondary electrolytic treatment using the light gray surface of matte as a base, and performing product processing as necessary, for example, An extruded architectural product may be used.

The aging treatment of the extruded material, the alkali etching treatment in the surface treatment step, the anodic oxidation treatment, the secondary electrolytic treatment used as required, the coating treatment, and the like, or the preceding steps are carried out by ordinary methods. What should I do?

At this time, the aging process is performed by, for example,
If heating is performed for about 2 to 8 hours in a high temperature atmosphere of about 240 ° C. to about 240 ° C., and then alkali etching is performed by a conventional method, for example, 1 to 20
A large number of craters having a diameter of about μm and a maximum of several tens of μm are formed so as to be uniformly distributed over the entire surface of the extruded profile, so that the extruded profile can have a fine and uniform matte surface.

FIG. 1 shows that Sn of 0.4 was added to the above alloy composition.
Extruded aluminum alloy containing wt%
FIG. 2 is a scanning electron micrograph of a surface subjected to a conventional alkali etching treatment by immersion in an H bath (aqueous solution at about 50 ° C. containing 50 g / l of NaOH) for 3 minutes, while FIG. Alloy number 6063 (alloy symbol A6063)
FIG. 3 is a scanning electron micrograph of the surface of the extruded material obtained by alkali etching under the same conditions as in S). In the case of FIG. 1 containing a small amount of Sn, the crater is evenly distributed over the entire surface, The matte treatment effect is extremely high, and the matte finish is fine and uniform. On the other hand, FIG.
Even if a satin finish is intended, the effect is extremely low, and etching mainly involves erosion along the grain boundaries, so that directional die lines and scratches generated during extrusion molding remain clearly. It is assumed that the glittering luster of the aluminum material remains while the portion is almost smooth.

Further, the extruded material whose surface is finely and uniformly pear ground by the alkali etching treatment as described above is subjected to an anodizing treatment by a conventional method. Then, the extruded material becomes a light gray surface of satin finish by alkali etching treatment and anodic oxidation treatment. At this time, the surface develops a light gray color by the anodic oxidation treatment because the anodized film formed on the matt surface by the anodizing treatment promotes irregular reflection and refraction of light together with the unevenness of the matte surface, and as a result, the light gray color It is considered that the color is visually observed. Therefore, by changing the processing conditions such as the added content of Sn, the liquid concentration of the alkaline etching process, and the processing time, the roughened state of the matte surface is changed, and the anodic oxidation process condition is changed to change the anodized film. If the thickness is changed, the color density of the light gray color can be controlled as much as possible.

As described above, the extruded material having a matte light gray color surface by anodizing is subjected to a coating treatment to produce various products by the light gray extruded material, for example, extruded materials for construction. If necessary, secondary electrolysis can be applied to the light gray surface of the matte as a base to deposit metal salts in the pores of the anodized film. As a result, it is possible to obtain an extruded profile of a predetermined color having a uniform color with a metal salt, so that a coating process is similarly performed to obtain a product of various colors, for example, a similar colored extruded profile product for a building. be able to.

In carrying out the present invention, aluminum alloy, its composition, extruded material, aging treatment, alkali etching treatment,
The specific configuration of the anodizing treatment, the extruded profile product, and the like, and additions to them, etc., may be in various modes as long as they do not contradict the gist of the present invention.

[0022]

EXAMPLES AND COMPARATIVE EXAMPLES As shown in Table 1, aluminum alloys were formed by changing the content of added chemical components. Examples 1 to 6 and Comparative Examples 1 and 2 were used. Comparative Examples 3 and 4 were made by changing the additive content of the chemical components of the aluminum alloy. Using a 75 mm diameter billet made of an aluminum alloy of each alloy composition, 550 ° C. × 4
After a homogenizing treatment for a time, the extruded material was heated to 450 ° C. and extruded at a speed of 4 to 15 m / min to obtain an extruded shape, and the extrudability was evaluated. In addition, alkali etching treatment and anodic oxidation treatment (thickness of the anodic oxide film: about 10 μm) were performed according to the usual methods, respectively,
The corrosion resistance was evaluated by performing a CASS test based on H8601. The extrudability and the corrosion resistance were based on the alloy No. 6063 of Comparative Examples 3 and 4, compared to this, and the equivalent was evaluated as poor, the inferior was evaluated as x, and the intermediate was evaluated as Δ. Further, the appearance of the anodic oxide film was evaluated, and the color tone (L * value, a * value, b * value) was measured. The appearance was evaluated as follows: A for a fine uniform pear surface with no visible die lines and scratches, B for a very rough pear surface with visible die lines and scratches, The sample having a rough surface on which die lines and scratches remain due to alkali etching was designated C. The color difference of the color tone was measured using a color difference meter CR-200 manufactured by Minolta Co., Ltd. On the basis of these results, a two-level evaluation of good or bad was made. Table 2 shows the results of each evaluation.

[0023]

[Table 1]

[0024]

[Table 2]

Further, the extruded sections made of the aluminum alloys of Examples 1 and 6 and the extruded section of alloy No. 6063 of Comparative Example 3 were subjected to an aging treatment for 2.5 hours under the respective temperature conditions.
Each hardness was measured based on the Vickers hardness test method of JIS Z 2244. Table 3 shows the results.

[0026]

[Table 3]

As shown in Table 2, the above results show that Examples 1 to 6 all have a fine and uniform pear surface, in which die lines and scratches cannot be visually recognized, and are indicators of lightness. * The value also decreased with the amount of Sn added, and exhibited a light gray color, and the corrosion resistance was extremely good. In Example 76, when the extrusion speed was high, there was a tendency for some seizure defects to be observed. Therefore, the evaluation of the extrusion moldability was evaluated as “△”. It became. Further, as shown in Table 3, by performing the aging treatment, it is possible to secure hardness equal to or approximately equal to that of the aluminum alloy of alloy number 6063.
At an aging temperature of 0 ° C, alloy number 606 at altitude
Exceeds the aluminum alloy of No. 3 and makes it possible to obtain highly extruded extruded members. The reason is considered to be that the addition of Sn acts to suppress the age hardening in the low temperature region, but promotes this in the high temperature region.

[0028]

The present invention is configured as described above.
According to the first to third aspects of the present invention, an extruded material having a light gray surface as a fine and uniform satin surface, which is preferable as a high-quality product, can be produced as easily and reliably as possible in a general surface treatment step. It is possible to provide an extruded aluminum alloy which is suitable for industrial use, has excellent corrosion resistance and hardness, and can meet the demand for decorativeness due to its excellent appearance. The invention described in (1) is excellent in corrosion resistance and hardness, having a light gray surface as a fine and uniform pear surface or colored as a coloring base, which is preferable as the high quality product using the aluminum alloy. It is possible to provide an extruded architectural product for a building that can meet the demand for decorativeness due to its excellent appearance.

[Brief description of the drawings]

FIG. 1 is a scanning electron micrograph showing a state of a matte surface of an extruded material containing a small amount of Sn.

FIG. 2 is a scanning electron micrograph showing the surface condition of an extruded material of alloy number 6063.

Claims (5)

[Claims] 1. An aluminum alloy for an extruded shape used to make an aged extruded shape into a light gray surface of satin by alkali etching and anodizing, wherein the aluminum alloy is an extruded shape. An aluminum alloy for an extruded profile, characterized by having a predetermined alloy composition for use and containing a small amount of Sn in addition to the alloy composition. 2. The extruded aluminum alloy according to claim 1, wherein the addition of the trace amount of tin is 0.3 to 0.8 wt%. 3. The method according to claim 1, wherein the predetermined alloy composition for the extruded profile is M
g is 0.4 to 0.9 wt% and Si is 0.2 to 0.6 wt%.
The extruded aluminum alloy according to claim 1 or 2, wherein the composition contains 0.1% to 0.4% by weight of Fe and 0.1% to 0.4% by weight of Fe, with the balance being Al and unavoidable impurities. 4. An extruded aluminum alloy according to claim 1, 2 or 3, which has been subjected to an aging treatment by extrusion molding, and then subjected to an alkali etching treatment and an anodic oxidation treatment to give a light gray color of satin finish. An extruded architectural product characterized by being a surface. 5. An extruded aluminum alloy according to claim 1, 2, or 3, which has been subjected to aging treatment and then subjected to an alkali etching treatment and an anodic oxidation treatment to obtain a light gray color of satin finish. An extruded architectural product having a surface and being colored by a secondary electrolytic treatment.