JP2813549B2 - Method for producing Al-Mn-Mg alloy plate for building panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Al-M material suitable for an exterior panel of a building such as a building, in particular, a high-temperature baking coating panel.
The present invention also relates to a method for manufacturing an n-Mg-based alloy plate.

[0002]

2. Description of the Related Art Al used for exterior panels of buildings
A1100-H has been conventionally used as a plate and an Al alloy plate.
14 materials (Al system) and A3003-H24 material (Al alloy system) are used. These general manufacturing steps are:
Ingot making → homogenizing heat treatment → hot rolling → cold rolling → finishing annealing (partial annealing) as required to produce architectural plate materials (thickness: 1 to 6 mm), and to use this plate material as a curtain wall manufacturer Then, after cutting into a predetermined size and bending the end portion, a surface treatment such as painting or anodizing is performed.

[0003]

With respect to architectural plate materials, in recent years, high-temperature baking coatings such as fluororesin paints have been increasing from the viewpoint of corrosion resistance, weather resistance, stain resistance and the like. But A
For 1100 material, this high temperature baking treatment (usually 240 to 2
60 ° C.), the material strength is greatly reduced, and there is a problem that the proof stress value (95 N / mm ² ) required for the strength design cannot be satisfied. Also, as shown in FIG.
When bending (inner radius [R] = 0 ° bending), bend
The inner side 2 is bent to the inner radius R = 0 ° and outside
Ideally bends on side 3 without cracks or rough skin
On the other hand, in A3003 material, as shown in FIG.
There are cracks 4 and rough skin.
The inside 2 does not bend sharply as shown in FIG.
(R = n). Further, any of the materials has a problem that the strength and flatness of the plate change during high-temperature baking. Flatness here means that when the board is hot-baked, the internal stress of the board is released,
The board is warped or bent, and the degree of flatness changes
That means. The building panel, it good this flatness is required. The present invention has been made as a result of intensive studies to solve these conventional problems (the problem of strength and stability after high-temperature baking coating, the problem of flatness, and the problem of bending workability).

[0004]

Means for Solving the Problems That is, the present invention relates to Mn
0.8-1.5% (% by weight, the same applies hereinafter) and MgO.
5 to 1.5%, the balance being Al and inevitable impurities
The ingot obtained by melting and casting an aluminum alloy
Hot rolling, cold rolling, and then intermediate annealing
Cold rolling at a rolling reduction of 15 to 25%
Architectural panel characterized by final heat treatment at 00 ° C
This is a method for producing an Al-Mn-Mg-based alloy plate for use.

[0005]

Next, the reason why the method of the present invention is performed as described above will be described. The reason that the Al alloy is limited to the Al-Mn-Mg-based alloy is that pure Al-based alloy such as A1100 and Al-Mn-based alloy such as A3003 have insufficient strength because of insufficient strength.
An Mn-Mg alloy was used. In this case, Mn is 0.8-1.
It is desirable that 5 wt% and Mg be 0.5 to 1.5 wt%. If less than the lower limit, a predetermined strength cannot be obtained, and if the upper limit is exceeded, a coarse intermetallic compound is crystallized and becomes a surface defect,
This is because rolling becomes difficult. If necessary, Cu and Cr may be added in an amount of 0.25 wt% or less for the purpose of improving the strength and the like. Also, for the purpose of refining crystal grains, Ti
You may add 0.05 wt% or less and B 0.005 wt% or less. In addition, impurities such as Fe, Si, and Zn are generally Al.
The degree contained in the metal does not affect the present invention.

[0006] Such an alloy ingot is subjected to a homogenizing heat treatment according to a conventional method, followed by hot rolling to a sheet thickness of 4 to 6 mm. Usually, the homogenizing heat treatment is performed at 480 to 620 ° C for 2 to 5 hours, and the hot rolling is performed at 500 to 300 ° C. Next, it is annealed after cold rolling according to a conventional method. 20 for cold rolling
% Or more is preferable. If the amount is less than this, the material is not kneaded well. Annealing is usually 1 to 3 at about 320 to 400 ° C.
Implemented for hours.

Next, this is cold-rolled at a rolling rate of 15 to 25%. This is because a predetermined strength is obtained by this cold rolling. 1
If it is less than 5%, the strength is low, and if it exceeds 25%, strength and flatness after high-temperature baking are unstable, and bending workability is poor. Next, the cold-rolled sheet is heated to 260 to 300 ° C.
For the final heat treatment. This heat treatment is for stabilizing the strength and flatness by high-temperature baking coating and for improving the bending workability. If the temperature is lower than 260 ° C., these properties cannot be obtained, and if the temperature exceeds 300 ° C., a predetermined strength cannot be obtained. The heat treatment time is desirably 1 to 3 hours in this temperature range. A manufactured by the method described above
The alloy plate is excellent in bending workability, the strength (proof stress) after high-temperature baking coating is 90 N / mm ² or more, and the strength and flatness before and after high-temperature baking coating are stable with almost no change.
It has excellent properties as a building panel material.

[0008]

Next, examples of the present invention will be described together with conventional examples and comparative examples. Example 1 An Al—Mn—Mg based alloy according to the present invention having the composition shown in Table 1 and a conventional alloy A1100
An alloy (Al-0.15 wt% Cu alloy) and an A3003 alloy (Al-1.2 wt% Mn-0.15 wt% Cu alloy) are melt-cast and have a thickness of 600 mm x a width of 2200 mm x
The ingot was 4000 mm in length. This was chamfered on both sides (10 mm per side) and subjected to a homogenizing heat treatment. This was hot-rolled at 500 to 300 ° C. to a thickness of 5.0 mm.

From then on, each material was manufactured as follows.・ Al-Mn-Mg alloy sheet according to the present invention Hot rolling → Cold rolling → Intermediate annealing → Cold rolling Sheet thickness 4.2mm 360 ° C x 2H Sheet thickness 3.0mm → Final heat treatment 280 ° C x 2H ・ Conventional material A1100-H14 sheet hot rolling → cold rolling Sheet thickness 3.0mm ・ Conventional material A3003-H24 sheet hot rolling → cold rolling → finish annealing (partial annealing) Sheet thickness 3.0mm 255 ° C × 3H

These sheets were subjected to a tensile test (measurement of proof stress), a bending test and a flatness test shown in FIG. The bending test was performed as shown in FIG. When the inner radius R was bent to 0 ° as shown in (a), it was determined based on the presence or absence of surface cracks and rough skin, and whether or not the inner side was sharply bent (good, poor rough, sharply curved). Not present, x causing cracks). In addition, the flatness test was performed on Joban by 3 mm x 2500 mm x 2500 mm.
And measure the maximum gap (mm) between the Joban and the plate,
1 mm or less was accepted and 1 mm or more was rejected. The results are shown in Table 1. These plates were baked with a fluorine-based resin (baking coating conditions: 250).
C. x 20 minutes). These sheets were subjected to a tensile test (measurement of proof stress) and the flatness of the sheets. The results are shown in Table 1.

[0011]

[Table 1]

As is apparent from Table 1, the material of the present invention is excellent in bending workability, and has a strength (proof strength of 90 N / m) after high temperature baking coating.
m ² or more), the strength and flatness before and after high-temperature baking were stable, and the flatness itself was also excellent.

[Embodiment 2] N according to the present invention in Embodiment 1
o. For the Al-Mn-Mg alloy No. 1, a plate having a cold rolling ratio and a final heat treatment condition within the range of the present invention and a plate outside the range as shown in Table 2 were manufactured and tested. The manufacturing conditions and test methods for the other plates are the same as in Example 1. Table 2 shows the test results.

[0014]

[Table 2]

As is clear from Table 2, the method according to the production method of the present invention has the following properties: bending workability, strength before and after high-temperature baking coating,
It turns out that it is excellent in flatness.

[0016]

As described above, according to the method of the present invention, the strength (proof strength) and the bending workability are particularly excellent, and the strength (proof strength) and flatness before and after high-temperature baking coating are particularly superior to the conventional plate material for building panels. It is stable without change, and is excellent in flatness itself required for building panels, and is suitable as a plate material for large building panels.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a bending process according to the present invention, in which (a) shows a normal state, (b) shows a state in which cracks are generated on the surface, and (c) shows a state in which the surface is not sharply bent.

[Explanation of symbols]

 1 Board 2 Inner radius R = 0 ° part 3 Bending surface part 4 Crack

────────────────────────────────────────────────── ─── of the front page continued (51) Int.Cl. ⁶ identification symbol FI C22F 1/00 630 C22F 1/00 630K 672 672 682 682 683 683 685 685Z 686 686Z 691 691B 694 694A (58) investigated the field (Int .Cl. ⁶ , DB name) C22F 1/04 B21B 3/00 C22C 21/00 E04C 2/08

Claims (1)

(57) [Claims] 1. Mn 0.8 to 1.5% (% by weight, hereinafter the same)
) And 0.5-1.5% of Mg, with the balance being Al
Dissolves aluminum alloy consisting of unavoidable impurities
Hot rolling and cold rolling of the cast ingot after homogenizing heat treatment
Cold rolling at a rolling reduction of 15 to 25%
And then perform a final heat treatment at 260-300 ° C.
Manufacture of Al-Mn-Mg alloy plates for building panels
Construction method.