JPS6167800A - Surface treatment for forming pattern of aluminum alloy - Google Patents

Abstract

PURPOSE:To generate a beautiful grain like colored pattern having an appearance of natural wood and good workability by forming a colored oxide film electrochemically after the imperfect aging hardening processing the substrate pattern provided mechanically on the surface of an Al alloy material. CONSTITUTION:A substrate pattern is provided by high pressure water spraying and blasting for an Al alloy material 1 traveling on a carrier conveyer 2 after extrusion moulding. For example, a belt 3, such as a rubber sheet and the like cut-out in a shape of the pattern on the surface of a shaping material 1 is rotated, transferred transversely to the direction of the traveling of the material 1 of a nozzle 4 and a grinding material is projected by approximately #30-#400 in particle size and 2-6kg/cm<2> at the delivery pressure from the nozzle 4. After the imperfect aging hardening for the material 1, a color oxide film is formed on the surface of the material 1.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a decorative woodgrain pattern with a natural wood texture consisting of light yellow to brown color on the surface of an aluminum alloy (excluding pure aluminum) having age hardening performance. It relates to a surface treatment method that can clearly produce It is possible to create a beautiful light yellow to brown colored pattern on the aluminum alloy surface that has the texture of natural wood and has a clear contrast between the wood grain and the background, as well as a corrosion-resistant colored film. The patterning of aluminum alloys that can be formed is related to the surface treatment method.

Conventional technology Conventionally, a method of producing a colored pattern on the surface of an aluminum material using artificial age hardening treatment was disclosed in Japanese Patent Application Laid-open No. 53
-83941 is known. This technology involves attaching a desired patterned sheet to the surface of an aluminum material, subjecting it to artificial age hardening under normal conditions, removing the patterned sheet before or after cooling, and then removing the patterned sheet from the aluminum material. This is a method of producing a colored pattern on the surface of an aluminum material by electrolytically coloring it as an anode. The generation mechanism of the colored pattern in this method is that during the age hardening treatment, heating causes a difference in the crystal structure between the areas where the patterned sheet is attached to the aluminum material and the area where it is not attached. It creates a pattern during electrolytic coloring.

However, this technique has the following drawbacks.

a) Age hardening treatment Inside the furnace, the temperature is not necessarily uniform between the left and right, top and bottom, front and rear ends and the center, and there are temperature differences, making it difficult to control the pattern of the product obtained.

b) Aluminum material has very good heat conduction, so
It is difficult to create a temperature difference between the attached part of the patterned sheet and the unattached part. Therefore, it is difficult to produce a colored pattern with a clear difference in shading, and it is also difficult to make small patterns such as a spotted pattern, a polka dot pattern, and a woodgrain pattern appear on an aluminum material.

C) The process of attaching and detaching the patterned sheet is reliable, and since a patterned sheet must be prepared for each shape of the extruded shape, workability is extremely poor and the resulting product is costly. Get high.

Furthermore, as another method for forming a patterned oxide film, the method described in Japanese Patent Publication No. 43-6365 is known. This technology uses an aluminum alloy with a specially selected composition of AL-Mn-Mf alloy, stretches the aluminum alloy, applies special heat treatment during or after the processing process, and then anodizes the aluminum alloy. This is a method of producing a contrasting black and white pattern on the aluminum alloy surface due to the precipitation of the AL-Mn binary compound.

The patterns obtained by this method are completely random in form, and it is not possible to obtain arbitrary patterns, and the patterns are also limited to the contrast of black and white, so it is still impossible to obtain decorative and beautiful colored patterns. There is a problem with this.

Problems to be Solved by the Invention Therefore, the first object of the present invention is to provide a patterned aluminum alloy that is easy to work with and can produce a beautiful wood-grain colored pattern with a natural wood texture on the surface of the aluminum alloy. An object of the present invention is to provide a surface treatment method.

A second object of the present invention, in relation to the above object, is that by making the wood grain part of the colored pattern yellow ocher and the background pale yellow, it is possible to create an extremely clear colored pattern with different shading. The purpose of patterning aluminum alloy is to provide a surface treatment method.

Means and Effects for Solving the Problems The present invention provides a method of applying a base pattern to an aluminum alloy after extrusion molding by mechanical manipulation, instead of the conventional complete age hardening treatment after extrusion molding. , by performing incomplete age hardening treatment, and further applying a pale yellow to brown colored film to the aluminum alloy by electrochemical operation, forming a base pattern by the mechanical operation, incomplete age hardening treatment, and electrochemical treatment. Due to the mutual effect of each step of forming a target-colored film, a difference in color shading occurs between the base pattern area and the background (non-patterned area), and the base pattern appears extremely clearly on the surface of the aluminum alloy. This is based on the knowledge that it is possible to produce beautiful wood-grain colored patterns with the texture of natural wood.

That is, the first invention according to the present invention provides a coating of 100 to 3000 (Ky /
A base pattern is applied between the traced part and the non-traced part by high-pressure jetting of liquid at a discharge pressure of cm2), and then the aluminum alloy is subjected to incomplete age hardening treatment, and then the aluminum alloy surface is Patterning of aluminum alloy is a surface treatment method characterized by clearly exposing the base pattern on the surface of the aluminum alloy by forming a pale yellow to brown colored oxide film.

In addition, the second invention according to the present invention has a particle size V'30 to #400 and a discharge pressure of 2 to
A ground pattern is applied by projecting an abrasive material under the conditions of 6 Ky/t, and then the aluminum alloy is subjected to incomplete age hardening treatment, and then the aluminum alloy surface has a pale yellow to
Patterning of an aluminum alloy is a surface treatment method characterized by clearly exposing the base pattern on the surface of the aluminum alloy by forming a brown colored oxide film.

Aspects of the Invention Next, each step of the present invention and its aspects will be explained in detail.

(A) Base pattern formation process First, the aluminum alloy (hereinafter referred to as aluminum (abbreviated as "alloy") is applied with a base pattern by mechanical manipulation.

According to the first invention, this base pattern is created on the aluminum alloy surface by a high-pressure injection method in which liquid such as water is injected at high pressure, and according to the second invention, by mechanical operation means of the plasto method in which sand, iron powder, etc. are sprayed. It is applied to

To be more specific, for example, with the aim of improving workability,
Immediately after extruding the aluminum alloy, a mold or metal frame (jig) that has the same shape as the extrusion mold and has a certain clearance is provided with injection grooves (holes) for high-pressure injection, for example at straight-grain intervals, and water or Continuous surface conditioning while spraying abrasives, etc.
By applying a base pattern (applying a base pattern), it is possible to apply a base pattern to even complex-shaped irregularities. In this case, a desired continuous pattern (for example, a pattern with long straight grain intervals as in printing, a pattern with varying shading, etc.) can be easily provided.

Such a base pattern forming treatment can be applied to aluminum alloy sections at a high temperature immediately after extrusion or at a cooled low temperature, and also to aluminum alloy sections after extrusion and cutting. Each case will be explained in detail below.

(1) Immediately after extrusion (when extruded and running on a conveyor), a base pattern is applied to the high-temperature or cooled low-temperature aluminum alloy shape by high-pressure water jetting or blasting.

a) High-pressure injection method Factors that give impact to aluminum alloy include: ■Type of discharged material, ■Nozzle diameter, ■Work speed, ■Nozzle distance, ■Discharge pressure, ■Discharge method, etc.

Currently, clean water is the most suitable material for the ejected material (2) because it is inexpensive. Further, a small amount of an abrasive material such as alumina oxide, S i 02, etc. may be mixed into the liquid. This has the advantage that the discharge pressure can be reduced. The nozzle diameter of (2) is 0.1 snφ~0.
A range of 4 cabinets φ is preferable. If it exceeds this range, the device will become bulky, while if it falls below this range, the nozzle will become clogged, which is not preferable. The work speed of ■ is set at a maximum of about 70 m/G. If it is larger than this, the pattern will be blurred and some pulsating flow will be picked up (however, this will change somewhat depending on the discharge pressure, etc.)
So I don't like it. Also, the nozzle distance is 5 to 2.
00! A range of IJ is preferred. Below this range, the work will hit the nozzle, while above this range, the device will become larger.

■Discharge pressure is 100Kg/m2 to 3000 to 7/c
1n2 is appropriate. If it is less than this, the impact force will be small and the formation of the base pattern will not be sufficient, while if it is more than this, the shape of the aluminum alloy shape will change drastically (provided that fresh water is the standard), which is not preferable. (2) As a discharge method, there is a method of using a header type nozzle or a method of drawing in air using an ejector type. In the case of a one-header type, the more headers there are, the easier it is to entrain the air discharged from the nozzle, which causes a greater impact on the aluminum alloy.

b) As the blasting material, any inorganic metal or non-metal can be used, but alumina oxide or one mainly composed of alumina oxide is preferable.

The particle size of the abrasive is set in the range of 30-400. The upper limit of 30 is approximately the diameter of a standard sieve that passes through 100 meters,
As a result, the nozzle diameter needs to be 3 pores, which is the limit for linear patterns such as straight grain.

On the other hand, if it is finer than #400, the surface roughness after treatment will be small and the matte texture will be weak (low degree of work hardening), recovery will be difficult, and workability will be poor, which is not preferable.

Further, the minimum diameter of the nozzle to be used is about three times the particle size of the abrasive, and it may be necessary to use a nozzle with a larger diameter.

The conditions for the blasting method are a blood pressure type and a nozzle diameter of 0.5~
1.2 throat φ is preferable, projection distance 5-30111
If it is less than I+1 (5■), there is a strong risk of contact with the workpiece, while if it is more than 30m, the pattern width will be wide,
(Unfavorable as the pattern itself will be blurred), air pressure 2-6
Kg/cm (The reason for setting this range is the same as the reason for setting Q) regarding the discharge pressure of the high pressure injection method).
Set by a combination of abrasive particle size, projection density, distance, nozzle diameter, and moving speed of the nozzle or workpiece. The number of nozzles can be up to 50 per set, and straight-grain patterns can be efficiently processed. The speed of the nozzle or workpiece is preferably set to 20 m/min or less, preferably 1 min.
Set within 0m/min.

(2) Extrusion - A base pattern is applied to the cut aluminum alloy shape by high-pressure water jetting or blasting.

The method for forming the base pattern is similar to the method detailed in (1) above. When using the blasting method, a certain pattern can be exposed by using a masking material. In this case, either direct pressure type or suction type (moaning) may be used, and the particle size of the abrasive material, the projection speed (air pressure,
The projection distance), projection density, projection angle, etc. are based on the conditions described above and the general plastic blasting conditions for aluminum. For example, the following embodiments are suitable for blasting using a masking material.

(1) Placing a patterned rubber sheet, synthetic resin sheet, etc. on the aluminum alloy shape and masking it.
Alternatively, masking is done by screen-printing an ultraviolet curing paint, etc., or cutting out a synthetic resin sheet in a pattern and pasting it with adhesive, and then performing the blasting process while moving the nozzle or aluminum alloy shape. .

In this case, the aluminum alloy profile can be moved continuously.

(11) A belt made of a rubber sheet or the like cut out in a pattern is rotated to perform blasting while continuously masking the aluminum alloy profile. For example, as shown in FIG. 1, seat belts 3 cut out in a pattern are rotatably placed at predetermined positions on a conveyor 2 that conveys an aluminum alloy profile 1 at regular intervals. A device equipped with a nozzle 4 for spraying the abrasive material is used. The nozzle 4 is movable left and right with respect to the direction in which the aluminum alloy section 1 moves. When such a device is used, the nozzle 4
The abrasive material injected from the seat belt 3 passes through the cutout hole and hits the aluminum alloy profile 1 being conveyed by the conveyor 2, so that the base pattern corresponding to the cutout pattern of the seatbelt 3 is formed on the aluminum alloy profile. 10 surfaces.

(liil) A synthetic resin film cut out in a pattern is coated with an adhesive, and then blasted while bonded to an aluminum alloy profile.For example, a method such as the one shown in Figure 2 is used. In the figure, 1 is an aluminum alloy profile, 2 is a conveyor, and 4 is a nozzle.
Here too, the nozzle 4 is movable left and right with respect to the traveling direction of the aluminum alloy section 1. Reference numeral 5 denotes a masking sheet in which a release paper 6 and a film 7 are laminated together and are cut out in a pattern. Although it is not necessary to use a sheet having such a structure, if the sheet lacks stability because it has many pattern-cut parts, it is preferable to attach a release paper as described above. Masking sheet 5
moves in the direction of the arrow along with the aluminum alloy profile 1 while being pressed onto the aluminum alloy profile 1 by the pressure roller 8, and before being subjected to the blasting process, the release paper 6 is first wound up by the take-up roll 9, and after the blasting process Film 7 is winding roll I
It is wound up by Q. In this way, the abrasive material sprayed from the nozzle 4 passes through the cutout holes in the pattern of the film 7 and hits the aluminum alloy profile 1 being conveyed by the conveyor 2, forming the cutout pattern in the film 7. A corresponding base pattern is applied to the surface of the aluminum alloy curved material 10. the above(
Both of 11) and 411) can be performed continuously.

The formation of this base pattern is caused by the subsequent incomplete age hardening treatment (
Due to the interaction of the first incomplete age hardening treatment (first incomplete age hardening treatment and the second incomplete to complete age hardening treatment) and electrochemical coloring treatment, the four R's of the scratched area become the base or core of the colored pattern. (9) The depth is not an essential element for surface conditioning (base pattern formation), but it is sufficient to be within the dice mark to pass the appearance, and even in the state after the oxide film is formed.
Even when observed under a microscope, there is no noticeable deterioration in performance due to the scratches.

(B) Incomplete age hardening treatment step 5 The aluminum alloy profile provided with the base pattern as described above is then subjected to incomplete age hardening treatment. Although this incomplete age hardening treatment step can be carried out in one step, it is preferable to carry out it in two steps as follows.

(a) Primary incomplete age hardening treatment step The primary age hardening treatment is carried out under conditions where the aluminum alloy does not reach complete aging.

To explain age hardening treatment, for example, aluminum alloy A
-60.33. In the case of S material, the effects of age hardening temperature and time on the hardness of the alloy are shown in Figure 3 (1G). That is, the hardness reaches its maximum value after a certain period of time at any temperature, and age hardening at this stage is defined as complete age hardening.

Therefore, what is incomplete age hardening? It means age hardening before reaching the stage.

Although FIG. 3 shows the state of high temperature aging or artificial aging, the incomplete aging referred to here is not limited to this, but also includes room temperature aging or natural aging. Therefore, to put it in an extreme case, it may be left to stand for a long time to allow natural aging.

(Yama) Secondary incomplete to complete age hardening treatment process This is
This means that it may be either incomplete age hardening or complete age hardening. This secondary age hardening treatment is performed at a higher temperature than the first age hardening treatment.

Regarding the effect of the two-stage age hardening treatment, for example, the primary aging (1
Figure 4 shows the combination of aging (60°C) and secondary aging (19o'c) and the effects of the conditions.

As is clear from Figure 4, under all conditions,
The combination of primary aging and secondary aging is 190°C x 6hr I
It has the effect of increasing the hardness compared to the step full age hardening treatment. By combining the primary and secondary age hardening treatments that achieve this effect, subsequent coloring treatments (C) and (C')
, (c') makes the surface-adjusted areas (underlying pattern areas) such as scratches or creases dark in color, making it possible to create a pattern with color contrast. Another effect is that sufficient hardness can be imparted to the aluminum alloy before electrolytic treatments such as anodic oxidation, electrolytic coloring, oxide film modification, and electrolytic coloring.

Note that Figure 4 shows the results when cooling to room temperature between the primary and secondary age hardening treatments, but the effect described above will not occur unless a cooling process is included between the primary and secondary aging treatments. It becomes less. Therefore, it is preferable to include a cooling process between the primary and secondary age hardening treatments, which increases the hardness even further than a simple two-step age hardening process. The difference in color shading between the pattern and the background (non-patterned area) becomes even larger.

In addition, the temperature difference between the temperature of (B) (a) primary incomplete age hardening treatment and the temperature of (b) secondary incomplete age hardening treatment or secondary complete age hardening treatment is set at 5°C to 60°C. It is preferable to do so. The reason for this is that if the temperature is lower than 5°C, the effect of dividing the age hardening treatment into two stages will not clearly appear, and sufficient hardness and sufficient difference in color shading in the coloring treatment will not be obtained. The reason for setting the upper limit at 60°C is that if there is a temperature difference greater than this, the temperature for the primary incomplete age hardening treatment will be lower, which will lengthen the treatment time, reduce efficiency in the manufacturing process, and cause problems. This is because it is an economic matter.

Further, FIG. 5 shows the appropriate range of time and temperature for the first incomplete age hardening treatment in the two-stage age hardening treatment.

Particularly preferable ranges are shown within the shaded areas.

(C) Colored film treatment process The aluminum alloy that has gone through each of the above steps (A) and (B) is subjected to treatments such as degreasing, washing with water, and removing smut as necessary by a conventional method, and then subjected to the following well-known process. A colored oxide film exhibiting a light yellow to brown color is formed on the surface of the aluminum alloy by any of the methods.

a) After anodizing the aluminum alloy in an electrolyte of an inorganic acid and/or an organic acid using a direct current or an alternating current or a current waveform similar to these, the aluminum alloy is anodized in an electrolyte containing an inorganic metal salt. A colored film exhibiting a light yellow to brown color is formed by electrolysis or direct current cathode electrolysis.

A colored film is formed by so-called anodic oxidation-electrolytic coloring. Electrolytes used for anodizing include well-known inorganic acids and/or organic acids, such as sulfuric acid, chromic acid, phosphoric acid, etc., mixed acid solutions thereof, oxalic acid, malonic acid, etc., or mixed acid solutions of these or with inorganic acids. Well-known electrolytes such as the following can be used, and the applied voltage and application time for anodic oxidation are sufficient as usual.

Examples of inorganic metal salts used for electrolytic coloring include sulfates, hydrochlorides, oxalates, tartrates, and chromium such as nickel, cobalt, chromium, copper, cadmium, titanium, manganese, molybdenum, tin, magnesium, silver, and lead. Various conventionally known salts such as acid salts and phosphates can be used, and conventional electrolytic conditions are sufficient.

For example, aluminum alloys that have been anodized are subjected to AC electrolysis in an electrolytic solution made by adding thiosulfate and formaldehyde to maintain the stability of the bath to an acidic bath of stannous sulfate. A uniform ocher-colored colored film with excellent properties is obtained (refer to Japanese Patent Publication No. 54-2366'2 Artifact).

b) In an electrolytic solution containing an inorganic acid with a metal salt added, or an electrolytic solution containing an organic acid, a colored film exhibiting a pale yellow to brown color is formed using an electrolytic coloring method that forms an anodized film on the aluminum alloy surface and simultaneously colors it. do.

Various methods are known, such as the ematal method and the Kalcolor method, and organic acids that cause color development of the anodic oxide film include various acids such as oxalic acid, malonic acid, sulfosalicylic acid, sulfophthalic acid, maleic acid, and tartaric acid. Mixed acid solutions are known.

C) A colored film exhibiting pale yellow to brown is formed by a natural coloring method in which an anodized film is formed on the surface of an aluminum alloy made of a naturally colored alloy in an electrolytic solution containing an inorganic acid, and color is developed at the same time.

Also known as the alloy coloring method, this method develops color when anodic oxidation is performed due to the influence of metals added to aluminum, and the coloration is unique to the alloy components. Generally, it is known that when the contained component is Cr, the color becomes yellow-brown, and when the content is Cu, the color becomes yellow-brown.

By electrochemically coloring using the various methods described above, a colored film with excellent corrosion resistance and weather resistance is formed, and the base pattern portion (scratches or distortions) is transformed into a background (non-patterned portion). The base pattern applied to the aluminum alloy surface by mechanical operation appears as a pale yellow to brown colored pattern.

The aluminum alloy that has been subjected to the colored film treatment in this manner is sent to a painting process as required, and is painted and baked by well-known methods.

By the way, in order to create a texture that is more similar to natural wood, the above (
Instead of the 0-colored film treatment step, it is preferable to employ the following steps: anodic oxide film treatment → oxide film modification treatment → coloring treatment.

Although the oxide film modification treatment is not necessarily essential, it is a process carried out for the purpose of making the contrast of the pattern clearer. That is, the colored film treatment ((,゛)
Although it may be sufficient on its own, oxide film modification treatment is performed in order to improve workability and improve decorativeness.

This condition may be the same electrolyte as the electrolytic solution for colored film treatment '), or an electrolyte with additives such as metal salts added to it, or a different electrolyte, but cathodic electrolysis in this electrolytic solution, alternating current or alternating current, or a different electrolyte may be used. Electrolyte treatment with a waveform that has the same effect.

For example, a standard combination is to perform anodization in a sulfuric acid bath, followed by alternating current electrolysis using the same electrolyte and carbon as a counter electrode. In addition, the same effect can be obtained by performing anodic oxidation and oxide film modification by changing the concentration, temperature, etc. of the same electrolytic solution as in the colored film treatment (f), and by adding additives, etc. .

Each step will be explained below.

(C') (1) , (C'') (1) Oxide film formation step As explained in (C) (a) above, in an electrolyte of inorganic acid and/or decomposed acid, direct current or alternating current or These similar current waveforms are used to anodize the aluminum alloy to form an oxide film.

Electrolytic conditions such as applied voltage and bath temperature are sufficient as usual.

(C) (ii) (C) (il) Oxide film modification step The oxide film on the surface of the aluminum alloy obtained as described above is modified by one of the following methods.

(C') (il) AC electrolytic reforming sulfuric acid, phosphoric acid,
In an electrolytic solution consisting of an inorganic acid such as chromic acid or an organic acid such as oxalic acid, the oxide film is double-layered by passing an alternating current or an electric current (two-meter waveform) having properties equivalent to this to the aluminum alloy. Modification is performed to form a film structure.The electrolytic conditions are the same as usual methods, but it is preferably carried out at 5 to 30 V for 1 to 30 minutes.

This secondary anodic oxidation treatment by AC electrolysis is not intended to produce a colored film, but in conjunction with the oxide film treatment described above, is to produce an oxide film with a double film structure.

Due to the formation of this double film structure, in the colored pattern formed by the subsequent coloring process, the difference in color shading between the base pattern portion and the background becomes remarkable, and the contrast of the colored pattern becomes clearer.

(C'Ei) Cathode direct current electrolytic reforming method In an electrolytic solution consisting of an inorganic acid such as sulfuric acid or phosphoric acid, the aluminum alloy on which the oxide film has been formed is connected to the cathode to generate direct current or properties equivalent to this. The aluminum alloy is energized using the current waveform.

This current treatment causes a dissolution effect on the oxide film on the aluminum alloy surface, but at this time, because the amount of current flowing is different between the base pattern and other parts (background), there is a difference in the quality of the film between the two. Get out. As a result, the contrast of the colored pattern becomes more noticeable through the subsequent coloring process.

The concentration of the electrolytic solution, the applied voltage, the time, etc. may be the same as usual, but preferably the conditions are 3 to 20 V and 20 seconds to 10 minutes.

<c>on), (C) OiO coloring treatment step The oxide film modified in the above step is colored by the method described in (C)(a) above. That is, AC electrolysis or DC cathode electrolysis is performed in an electrolytic solution containing an inorganic metal salt to form a colored film.

As a result, an extremely clear colored pattern with different shading is formed on the aluminum alloy surface.

Material Although pure aluminum is excluded in the present invention, various aluminum alloys can be used. Aluminum alloys are alloys whose strength is increased by quenching and tempering, that is, Cu, MW + Si as the main additives.

A suitable example is one containing Zn + Mft, etc., but it is not limited to this, and the color tone of the colored pattern and the contrast of the pattern can be adjusted by combining the additive elements, work hardening, heat treatment conditions, etc. . Further, in order to enhance the heat treatment effect and shorten the treatment time, the additive elements may be changed. For example, At-mt-
8i alloy or kl 'Mr S'
In the i Fe alloy, the combination of additives,
For example, by adding excess S1, age hardening can be promoted.

Therefore, for the purpose of improving color tone, pattern contrast, workability of processing steps, etc., it is possible to use an aluminum alloy with an alloy component suitable for the processing steps and conditions.

Effects of the Invention As described above, patterning of the aluminum alloy according to the present invention can be achieved by forming a base pattern by mechanical manipulation, incomplete aging hardening treatment, and forming an electrochemical colored film according to the surface treatment method. Due to the interaction of each process, a difference in color shading occurs between the base pattern part and the background, and the aluminum alloy surface exhibits excellent various performances such as corrosion resistance, weather resistance, and abrasion resistance, and exhibits a pale yellow to brown color. A beautiful colored pattern with the texture of natural wood can be created. Furthermore, by adding the oxide film modification step, the difference in color shading becomes even larger, and a colored pattern with clearer contrast and extremely excellent coloring properties can be obtained.

Furthermore, since a two-step age hardening process is adopted, mechanical strength, especially hardness, can be imparted to the aluminum alloy in a series of steps before anodizing or forming a colored film, and furthermore, immediately after extrusion, it is possible to impart mechanical strength, especially hardness, to the aluminum alloy. Because patterns can be formed, the surface treatment of aluminum alloys can be done in a manner that improves workability, productivity (and energy efficiency).In addition, since the underlying pattern is exposed as a colored contrast pattern, the surface treatment process is easier. The racking structure may be horizontally hung or vertically hung, and has the advantage that it does not require any new technology and can be handled satisfactorily using currently standardized methods.

In addition, the aluminum alloy shapes treated according to the present invention showed no deterioration in performance even after being given a base pattern, no defects were observed when observing the oxide film or colored film under a microscope, and various tests showed no deterioration in performance. It is no different from colored shapes and can be used freely for the same purpose, without any restrictions on interior or exterior use.

EXAMPLES The present invention will be specifically explained below with reference to Examples.

Example 1 Aluminum alloy (A-bob) naturally cooled after extrusion molding
38) Spray fresh water onto the surface of the profile from a nozzle diameter of 0.2 φ at a discharge pressure of 800 l (K9/cm:), a nozzle-work distance of 70 cm, and a work speed of 35 bar/min.
A base pattern was applied to the surface of the shaped material by spraying with water, and then a first incomplete age hardening treatment was performed at 150° C. x 511 hr, followed by a secondary age hardening treatment at 190° C. x 4 hr.

After that, the aluminum alloy shape is degreased, etched,
After removing the smut, the profile was immersed in a sulfuric acid aqueous solution of +sW/V% by a conventional method, and the current density was 1. Anodization treatment was performed under the conditions of 1A/dm (voltage approximately +2V), liquid temperature 20°C, and time 30 minutes to form an anodic oxide film of approximately 10 μm on the surface.

After washing with water, as a coloring treatment, the length is 200 mm, the width is 150 mm,
A container with a carbon counter electrode placed on one side end of a container with a height of 150 mm was used as an electrolytic coloring device, and the aluminum alloy shape with a length of 150 mm, a width of 70 mm, and a thickness of 1.3 mm was placed as a carbon counter electrode. With the distance between the poles l'80 mm, sulfuric acid 4
0t/11 sodium trithionate + y/l, sulfuric acid clause!
It is immersed in an electrolytic solution having a composition of tin 4 y/t at a temperature of 16°C, and the initial current density is l A /dm, l O
When alternating current electrolysis was carried out for 5 minutes and 30 seconds at an applied voltage of V, a beautiful ocher decorative pattern in which the base pattern was colored darker than the background appeared.

Example 2 A large number of nozzles with a nozzle diameter of 0.15 mmφ to 0.3 mmφ were placed on one side of the header at a pitch of 2 to 15 mm on the surface of an aluminum alloy (A-60638) shape immediately after extrusion molding. 1500 Kq / cln of fresh water from the header
A straight-grained base pattern was created between the traced area and the non-traced area by spraying at a discharge pressure of 50 m/min, a nozzle-work distance of 50 m/min, and a work speed of 40 m/min. Incomplete age hardening treatment was performed under the condition of hr.

After that, the aluminum alloy shape is degreased, etched,
After removing the smut, the profile was immersed in a 18 W/V% sulfuric acid aqueous solution at a current density of 1. IA/dm (voltage approx.
2V), a liquid temperature of 20° C., and a time of 30 minutes to form an anodized film of about 10 μm. continue,
As the oxide film modification treatment, a current density of 3A/3 was applied between the carbon counter electrode and the carbon counter electrode at the same concentration and temperature conditions as the anodic oxidation treatment bath.
dm (voltage approximately 8 V) for 8 minutes, and then the aluminum alloy shape was subjected to AC electrolytic coloring using the same apparatus as in Example 1 and under the same conditions. The base pattern part became a darker ocher color than the background, and there was more contrast than in Example 1, and the pattern appeared to have a straight-grain texture similar to that of natural wood.

Example 3 Aluminum alloy (A-60638
) By projecting alumina abrasive +20 onto the surface of the profile using a direct pressure blasting method with a nozzle diameter of 0-7 mmφ, a projection distance of 15 mm, an air pressure of 3 Kq/Cm, and a work speed of 7 rrt/min, A straight-grain base pattern with blurring is applied between the traced part and the non-traced part, and then incomplete age hardening treatment is performed at 165℃ for 3 hours, after which the vagina aluminum alloy shape is naturally cooled to room temperature. TL 200℃×2
Secondary age hardening treatment was performed under the conditions of br.

Next, in the same manner as in Example 2, degreasing, etching, smut removal, anodizing treatment, oxide film modification treatment, and coloring treatment were performed, resulting in a high hardness that cannot be obtained with ordinary one-stage age hardening treatment. Moreover, as in Example 2, the base pattern part became a darker ocher color than the background, revealing a pattern with a texture similar to that of straight-grained natural wood.

Example 4 Aluminum alloy (A-60638
) Alumina abrasive material +00 is projected onto the surface of the profile by blasting using a direct pressure method with a nozzle diameter of 1.0 mm, a projection distance of 10 mm, an air pressure of 4 KLi/Cnt, and a work speed of 9 m/min. Then, a straight-grain base pattern with blur between the traced part and the non-traced part was applied. Next, incomplete age hardening treatment was performed at 165°C for 3 hours, and then the aluminum alloy shape was Let it cool naturally to room temperature, then 200℃ x 2
A secondary age hardening treatment was performed under the condition of hr.

After that, the aluminum alloy shape is degreased, etched,
After removing the smut, the profile was immersed in a 18 W/V% sulfuric acid aqueous solution using a conventional method, and the current density was 1. IA/dm" (voltage approximately +2V), liquid temperature 20℃, and time 30 minutes to form an anodic oxide film of approximately 10 μm on the surface. After that, as an oxide film modification treatment, the current density Direct current electrolysis was carried out at 1.2 A/dm (voltage approximately 6 V) for 1 minute and 30 seconds by connecting the aluminum alloy profile to the cathode.

Next, after washing with water, as a coloring process, the length is 200 cm and the width is 15 cm.
A container with a length of 150 mm and a carbon counter electrode placed at one end of the container was used as an electrolytic coloring device.
The aluminum alloy shape having a width of 10+m++ and a thickness of 1.3m was set to a carbon counter electrode with a distance of 180 mm,
I was immersed in an electrolytic solution having the following composition at a bath temperature of 28°C.
When AC electrolysis was carried out with a voltage applied at IVO level, the underlying pattern became darker brown than the background, and a straight-grained pattern with a texture similar to that of natural wood appeared.

Liquid composition: Nickel sulfate 25y/magnesium sulfate 15f/ammonium sulfate 30? / boric acid
2ay/l ammonium thiosulfate +y/lP H5,
5 Example 5 An extruded aluminum alloy (A-60638) profile is placed on the conveyor of a blasting machine and sent to the projection chamber at a work speed of 5 m/min, but before entering the projection chamber, it is shaped like a grain pattern. Adhere the cut-out adhesive-attached PVC sheet (18-li) to the shape material while peeling off the release paper. The shape is made using direct pressure with a nozzle diameter of 8mm and a projection distance of 150mm.
Alumina abrasive #90 was applied under the conditions of air pressure 4 to 9/cr: to create a grain-like base pattern, and then incomplete age hardening treatment was performed at 165°C for 3 hours. Thereafter, the vagina aluminum alloy shape was naturally cooled to room temperature, and then subjected to a secondary age hardening treatment at 200°C for 2 hours.

Next, in the same manner as in Example 2, degreasing, etching, smut removal, anodizing treatment, oxide film modification treatment, and coloring treatment were performed, resulting in a high hardness that could not be obtained with ordinary one-stage age hardening treatment. Moreover, as in Example 2, the base pattern part became a darker ocher color than the background, revealing a beautiful board-like pattern with a texture similar to natural wood.

Comparative Example 1 The same procedure as Example 1 was carried out except that the discharge pressure was changed to 5oKg/♂ in Example 1, but the base pattern part was only colored a little darker than the background, and the decorative pattern was not too bright. It didn't happen.

Comparative Example 2 The same procedure as in Example 2 was carried out except that the age hardening treatment was carried out at 190°C for 7 hours. The texture was far from the straight-grained texture of natural wood.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an example of an apparatus for blasting aluminum alloy shapes according to the method of the present invention, Fig. 2 is a schematic diagram showing an example of another blast processing apparatus, and Fig. 3 is an aluminum Graph showing the influence of age hardening treatment temperature and treatment time on the hardness of alloy (A-60638), 4th
The figure shows the first aging (160℃) in two-stage age hardening treatment.
A graph showing the effect of the combination of and secondary aging (190°C) and the conditions on the hardness of aluminum alloy (1-60638), Figure 5 shows the appropriate range of time and temperature for the primary incomplete age hardening treatment. It is a graph. 1... Aluminum alloy profile, 2... Conveyor, 3
... Seat belt, 4... Nozzle, 5... Masking sheet, 6... Release paper, 7... Film.

Claims (1)

[Claims] 1. On the surface of the aluminum alloy after extrusion molding, 100 to 3
A base pattern is applied between the traced part and the non-traced part by high-pressure jetting of liquid at a discharge pressure of 0.000 [Kg/cm^2], and then the aluminum alloy is subjected to incomplete age hardening treatment. . A patterned surface treatment method for an aluminum alloy, which method comprises forming a pale yellow to brown colored oxide film on the surface of the aluminum alloy to clearly reveal the base pattern on the surface of the aluminum alloy. 2. Particle size ^#3 on the aluminum alloy surface after extrusion molding
A base pattern is applied by projecting the abrasive material under the conditions of 0~^400 and discharge pressure of 2~6 kg/cm^2, and then the aluminum alloy is subjected to incomplete age hardening treatment, and then the aluminum alloy surface is A patterned surface treatment method for an aluminum alloy, characterized in that the base pattern is clearly exposed on the surface of the aluminum alloy by forming a pale yellow to brown colored oxide film.