JPH05337511A - Method for producing rolled aluminum alloy plate with excellent paint clarity - Google Patents

Abstract

(57) [Summary] [Object] The present invention provides a method for producing a rolled aluminum alloy plate for processing, which is excellent in coating clarity. [Structure] A cold-rolled aluminum alloy rolled plate is temper-rolled using a working roll by a lithographic method or both a bright roll and a working roll by a lithographic method in order to adjust the surface thereof.
The unevenness is formed on the surface of the steel sheet, the wavelength λ of the uneven pattern is set to 500 μm or less, and the center line average roughness Ra is 1 to 5
It is a method for producing a rolled aluminum alloy plate for processing, which has a coating clarity in the range of μm and is excellent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a rolled aluminum alloy sheet (strip) for processing which is used for coating outer panels of automobiles and home electric appliances and which is excellent in coating clarity.

[0002]

2. Description of the Related Art Conventionally, rolled aluminum alloy plates used for press forming have a dull finished surface (D.C.) or a dull finished surface (R.D.C.) rougher than the dull finished surface. .) Are mainly used for durable consumer products such as automobiles and home appliances. Particularly, in the case of automobile materials and home electric appliance materials, R.I. is used for the purpose of improving moldability, preventing surface defects, and improving handleability. D. C
R. of which the surface was roughened using a rolling roll for D.
C. An aluminum alloy rolled plate having a finished surface is used. However, recently, from the general consumer's trend toward higher quality, the appearance after coating, especially the sharpness has come to be more important. In the surface properties of the rolled aluminum alloy plate as described above, It is difficult to provide the required appearance and good image clarity. Therefore, the above R. D. C. There has been a demand for an aluminum alloy rolled sheet having improved appearance and coating clarity without deteriorating the excellent characteristics of (1).

In order to improve the surface properties of the rolled aluminum alloy plate by the above-described conventional treatment, it is disclosed in Japanese Patent Laid-Open No. 3-71903 that the rolling amount is set to 20 μm or less by rolling using a laser processing rolling roll. Has been done. However, it is possible to transfer the uneven pattern on the surface of the rolled aluminum alloy plate from the laser-processed roll, but the crater interval is long, so a so-called "waviness" -like component with a large wavelength is produced, which causes a deterioration in coating clarity. There is a problem that it affects.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and when transferred to the surface of a work roll for rolling, there is no waviness and the like, and the coating image clarity is excellent. Moreover, it is an object of the present invention to provide a method for producing a rolled aluminum alloy plate having good workability.

[0005]

SUMMARY OF THE INVENTION In order to achieve a method for producing a rolled aluminum alloy sheet for processing which is excellent in coating clarity, the present invention has the following items. That is, (1) a hot-rolled aluminum alloy rolled plate is cold-rolled using a work roll, and the obtained cold-rolled aluminum alloy rolled plate has an uneven pattern wavelength of 500 μm or less and a center line average roughness R.
a is rolled by a work roll having a surface texture of 1 to 5 μm, and the rolled aluminum alloy plate has a concavo-convex pattern wavelength λ ≦ 500 μm and a center line average roughness Ra of 1 to 5 μm.
and a method for producing an aluminum alloy rolled sheet for processing excellent in coating sharpness characterized by finishing in a range of m, and (2) a cold rolled aluminum alloy rolled sheet using a work roll. The cold rolled aluminum alloy rolled plate was rolled with a work roll having a surface texture in which the wavelength of the concavo-convex pattern was 500 μm or less and the center line average roughness Ra was 1 to 5 μm, and temper rolling was further performed with a bright roll. A process for producing a rolled aluminum alloy plate having excellent coating sharpness, characterized in that the rolled aluminum alloy plate is finished to have a wavelength λ ≦ 500 μm of a concavo-convex pattern and a center line average roughness Ra of 1 to 5 μm, and (3)
A hot rolled aluminum alloy rolled plate is cold rolled using a work roll, the obtained cold rolled aluminum alloy rolled plate is rolled by a bright roll, and the wavelength of the uneven pattern is 500 μm or less and the center line average roughness Ra. Is 1 to 5 μm
By rolling with a work roll having the surface texture,
The aluminum alloy rolled plate is provided with a concavo-convex pattern having a wavelength λ ≦ 50.
This is a method for producing a rolled aluminum alloy plate for processing which is excellent in coating clarity and is characterized in that the finishing is performed in a range of 0 μm and a center line average roughness Ra of 1 to 5 μm.

[0006]

The present invention will be described in detail below. The present invention forms irregularities having a short roughness wavelength λ on the surface of a rolled aluminum alloy plate in order to improve the coating clarity. That is, by setting λ ≦ 500 μm, the influence of the shrinkage of the paint on the recesses formed on the surface of the aluminum alloy rolled plate during the paint baking treatment on the surface of the aluminum alloy rolled plate is reduced, and the unevenness on the aluminum alloy rolled plate is coated. It disappears at the top and the sharpness after painting can be improved. FIGS. 1 and 2 show a cross section of the surface portion of the coated aluminum alloy rolling plate. The wavelength λ of the unevenness in the aluminum alloy rolling plate 1 manufactured by the conventional method of FIG. 2 is large and is usually 600 μm.
Since the coating film 2 is formed along the unevenness of the waviness, the refraction of light is disturbed and becomes irregular and the image clarity of the coating is deteriorated. The aluminum alloy rolled plate 1 obtained by the present invention has a λ of 500 μ.
Since it is as short as m or less, the coating film 2 hides the uneven pattern of the rolled aluminum alloy plate, so that there is no adverse effect on the sharpness of the coating due to waviness unlike the conventional method.

Further, in the present invention, the workability is improved by adjusting the center line average roughness Ra together with the wavelength λ. That is, by forming regular irregularities on the surface of the obtained aluminum alloy rolled plate, this concave portion becomes an oil pool, and for example, punches and dies during press working and the convex portions of the aluminum alloy rolled plate surface, which is a processing member, are more evenly shaped than the concave portions. Since the oil is replenished, it is possible to reduce the wear coefficient during the processing. For that purpose, Ra of 1 μm or more is required. The larger the depth of the recesses, the greater the amount of oil retained, and evenly more oil is supplied to the protrusions on the surface of the processed aluminum alloy rolled sheet, which can further reduce the friction coefficient, but the difference between the irregularities is too large. If it becomes too much, the convex portion of the plate surface will be damaged during processing, and the damaged metal powder will be present between the rolled aluminum alloy plate and the punch or die to impair the workability. Therefore, the upper limit of Ra is 5
It is desirable that the thickness is μm.

In order to obtain the above-described rolled aluminum alloy plate of the present invention, the work roll surface in rolling must be processed to adjust the roughness of the unevenness. Conventionally, the roughness is directly imparted to the rolling roll by shot blasting, electric discharge dull processing, or by irradiation with a laser beam. For example, as shown in an enlarged cross section of the rolling roll in FIG. 3, this is formed. The uneven projections 4 on the surface of the roll 3 form undulations 5 having a large wavelength λ. As described above, the aluminum alloy rolled plate to which such waviness-like unevenness is transferred deteriorates in coating image clarity, and if the difference in the unevenness formed is large, the workability is also impaired.

According to the present invention, in order to improve the workability and the image clarity of a rolled aluminum alloy sheet, the work roll surface roughness applied to the surface of the rolled aluminum alloy sheet is made into a regular uneven projection, and there is almost no waviness component, or Even if it remains, an uneven pattern having an extremely short wavelength λ (λ ≦ 500 μm) is formed. That is, the rolled aluminum alloy plate rolled by this roll forms an appropriate roughness on the surface, stores lubricating oil to impart good workability, and is formed on the surface during paint baking treatment. The influence of the shrinkage of the paint on the recesses is reduced, and the irregularities on the rolled aluminum alloy plate disappear on the coating film, and the image clarity after coating can be improved.

The method for forming the uneven projections 4 on the surface of the roll 1 can be carried out by adopting a lithographic method as an example, as shown in FIGS. 4 (a) to 4 (d). That is, first, the liquid photosensitive resin 7 is supplied from the hopper 6 installed above the photosensitive resin feeder 9 to the photosensitive resin feeder 9, and the visible light photosensitive resin having high sensitivity is adjusted from the rear by the air 8 to a predetermined thickness. A photosensitive resin layer (film) 10 is formed by coating. Then, the photosensitive resin layer 10 is intermittently irradiated with a laser beam 12 in a visible region of a wavelength longer than an ultraviolet region emitted from a laser oscillator 11 at a predetermined regular pitch,
The photosensitive resin layer in this portion is cured 15 [(b) figure].
The photosensitive resin is 0.2 to 0.5 mJ for visible light.
Since it cures with an energy of / cm ² , an exposure time of 0.1 ms is sufficient. In FIG. (B), a chopper 14 having a slit 13 is used, and the beam 11 is intermittently irradiated while rotating the chopper 14. However, the invention is not limited to this, and for example, a pulse laser having a wavelength range shorter than the ultraviolet range or the like Is also good. Then, as shown in FIG. 6C, a dissolving agent 17 such as trichloroethane is sprayed from the sprayer 16 onto the surface of the roll that has been subjected to the above-mentioned treatment, and as shown in FIG. The photosensitive resin layer is removed by dissolution, and the roll surface 18 is exposed. After that, anisotropic etching is performed with a chemical corrosive agent to form recesses,
Form a regular uneven pattern. The roll processing method in the present invention is not limited to the above method, and any processing method can be used as long as the wavelength λ or this and Ra are within the scope of the present invention.
Either method may be used.

In the present invention, a cold-rolled aluminum alloy rolled plate is rolled by a working roll by the lithographic method or by using both a working roll and a bright roll by the lithographic method in order to adjust the surface. FIG. 5 schematically shows the uneven pattern of the aluminum alloy rolled plate, and FIG. 5 (a) shows each aluminum alloy rolled plate surface pattern when cold rolling followed by rolling with a lithographic processing roll, (B)
The figure shows the surface pattern of each rolled aluminum alloy plate when cold rolling followed by lithographic rolling and then by bright rolling, and (c) is the cold rolling followed by bright roll rolling. The surface pattern of each rolled aluminum alloy plate when rolled by a lithographic processing roll is shown.

[0012]

【Example】

Example 1 A hot rolled aluminum alloy rolled plate was cold-rolled by a conventional method to produce an aluminum alloy rolled plate having a thickness of 1.2 mm, and each surface unevenness pattern (λ, Ra) shown in Table 1 below was formed. Rolling with a work roll of 1.5% was carried out, and the obtained aluminum alloy rolled plate was subjected to a press working test. Further, after coating the rolled aluminum alloy plate (after rolling with a rolling reduction of 1.5%), the coating clarity was measured. The measurement test was based on JIS Z8741 “Specular gloss measurement method”. The results are shown in Table 1.

[0013]

[Table 1]

From the above results, the rolled aluminum alloy plate manufactured according to the present invention was manufactured by the conventional method and has a roughness pattern outside the range of the present invention. It can be seen that the paint clarity is significantly superior to that of No. 1.
Incidentally, the concavo-convex pattern of the work roll used in rolling was formed by using the above-mentioned lithography method.

Example 2 A hot-rolled aluminum alloy rolled plate was cold-rolled by a conventional method to produce an aluminum alloy rolled plate having a thickness of 1.2 mm, and each surface unevenness pattern (λ, The work roll having Ra) was rolled at a reduction rate of 1.0%, and then rolled at a bright roll at a reduction rate of 0.5%, and the obtained aluminum alloy rolled plate was subjected to a press working test. In addition, after painting on an aluminum alloy rolled plate (after bright rolling), the paint clarity was measured. The measurement test was based on JIS Z8741 “Specular gloss measurement method”. The results are shown in Table 2.

[0016]

[Table 2]

From the above results, the rolled aluminum alloy plate manufactured according to the present invention was manufactured according to the conventional method, and has a roughness pattern outside the range of the present invention. It is clear that the coating sharpness is remarkably superior to that of No. 1. Incidentally, the concavo-convex pattern of the work roll used in rolling was formed by using the above-mentioned lithography method.

Example 3 A hot rolled aluminum alloy rolled sheet is cold rolled by a conventional method to produce a rolled aluminum alloy sheet having a thickness of 1.2 mm, which is rolled with a bright roll at a rolling reduction of 0.5%. After that, the work rolls having the respective surface unevenness patterns (λ, Ra) shown in Table 3 below were used to reduce the rolling reduction to 1.
0% rolling was performed, and a press working test was performed on the obtained rolled aluminum alloy plate. In addition, after coating the rolled aluminum alloy plate (after rolling with a rolling reduction of 1.0%),
The paint clarity was measured. The measurement test is JIS Z8741
“Specular gloss measurement method”. The results are shown in Table 3.

[0019]

[Table 3]

From the above results, the rolled aluminum alloy plate manufactured according to the present invention was manufactured by the conventional method, and has a roughness pattern outside the range of the present invention. It is clear that the coating sharpness is remarkably superior to that of No. 1. Incidentally, the concavo-convex pattern of the work roll used in rolling was formed by using the above-mentioned lithography method.

[0021]

INDUSTRIAL APPLICABILITY As described above, the present invention is to modify the uneven component formed on the surface of the work roll, and by rolling using such a work roll, the component is formed on the surface of the aluminum alloy rolling plate. It is possible to produce an aluminum alloy rolled plate which is transferred to the steel sheet, has no waviness and the like, has excellent coating sharpness, and has good workability.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an example of a step of forming an uneven pattern on a roll surface of an expanded cross section of a rolled aluminum alloy plate obtained by the present invention,

FIG. 2 is a diagram schematically showing an example of a step of forming a concavo-convex pattern on a roll surface of an enlarged cross section of a coated aluminum alloy plate obtained by a conventional method,

FIG. 3 is a view showing a concavo-convex pattern on a roll surface which has been conventionally dull (concavo-convex) processed,

FIG. 4 is an explanatory view showing an example of an unevenness imparting processing step of the present invention by a lithography method,

FIG. 5 is a diagram schematically showing a concavo-convex pattern on the surface of a rolled aluminum alloy plate in each step when the treatment of the present invention is performed.

[Explanation of symbols]

 1 Aluminum alloy rolled plate 2 Coating film 3 Roll 4 Uneven projection 5 Waviness 6 Hopper 7 Liquid photosensitive resin 8 Air 9 Photosensitive resin supply device 10 Photosensitive resin layer 11 Laser oscillator 12 Laser 13 Slit 14 Chopper 15 Photosensitive curing part 16 Sprayer 17 Melting Agent 18 Exposed part

Claims (3)

[Claims] 1. A hot-rolled aluminum alloy rolled plate is cold-rolled using a work roll, and the obtained cold-rolled aluminum alloy rolled plate has an uneven pattern wavelength of 500 μm or less,
Rolling is performed with a work roll having a surface texture having a centerline average roughness Ra of 1 to 5 μm, and an aluminum alloy rolled plate has a wavelength λ ≦ 500 μm of a concavo-convex pattern and a centerline average roughness Ra of 1 to 5 μm. A method for producing a rolled aluminum alloy plate for processing, which is characterized by finishing and has excellent paint clarity. 2. A hot-rolled aluminum alloy rolled plate is cold-rolled using a work roll, and the obtained cold-rolled aluminum alloy rolled plate has an uneven pattern wavelength of 500 μm or less,
The center line average roughness Ra is 1 to 5 μm, which is rolled with a work roll having a surface texture, and further temper-rolled with a bright roll to make an aluminum alloy rolled plate have a concavo-convex pattern having a wavelength λ ≦ 500 μm and a center line average. Roughness Ra is 1 to
A method for producing a rolled aluminum alloy plate for processing, which is excellent in coating sharpness, characterized by finishing in a range of 5 μm. 3. A hot-rolled aluminum alloy rolled plate is cold-rolled using a work roll, the cold-rolled aluminum alloy rolled plate obtained is rolled by a bright roll, and the uneven pattern has a wavelength of 500 μm or less and a center. Line average roughness R
a is rolled by a work roll having a surface texture of 1 to 5 μm, and the rolled aluminum alloy plate has a concavo-convex pattern wavelength λ ≦ 500 μm and a center line average roughness Ra of 1 to 5 μm.
A method for producing a rolled aluminum alloy plate for processing, which is excellent in coating clarity, characterized by finishing in a range of m.