JPS5919185B2 - Manufacturing method of Al plate for name plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an Al plate for name plates, and more specifically, to an Al plate for name plates that has excellent surface properties by controlling hot rolling conditions and without heat treatment after hot rolling. The present invention relates to a manufacturing method for obtaining.

Generally, name plate material is made of industrial aluminum with an AI line purity of 99 or higher (usually referred to as line AI).

), it has a reflectance of about 80 when it is bright on one side, and has a very strong decorative element.

(1) Dials and nameplates for watches, meters, etc. that have been surface-treated by etching with NaOH solution and then alumite processing.

(2) Washing machine panels, etc. whose surfaces are coated or printed with paint or resin.

(3) After surface cutting such as spinning or hairline processing, alumite processing or patterning by applying paint is applied to the board.

In this way, name plate materials must satisfy each of these uses, but until now, the same material has been used to completely satisfy both uses (1) and (2). I couldn't get anything that satisfied me.

The reason for this is as explained below.

(1) When etching is performed mainly using a NaOH solution, the macrostructure of the material is exposed, and if this macrostructure is coarse, the decorative properties will be very poor.

(2) If there is a part to be coated with transparent paint, poor surface gloss or surface defects such as surface streaks are undesirable from a decorative standpoint.

In other words, in the current production method, (4) In the process of hot rolling → cold rolling → annealing → cold rolling (product plate thickness), the macrostructure is fine, but oil is produced in the first cold rolling after annealing. Many pits occur and cannot be completely removed by subsequent cold rolling, resulting in poor surface gloss.

Even in the process of hot rolling → annealing → cold rolling (product thickness), many oil pits occur during the first cold rolling after annealing, and cannot be completely eliminated by subsequent cold rolling. Therefore, the surface gloss is poor.

(C) In the process of hot rolling → cold rolling (product plate thickness), the macrostructure at the end of hot rolling usually becomes coarse or uneven, and the surface gloss is good (although it becomes coarse and rough). Alternatively, if the macrostructure is non-uniform, the decorative properties will be very poor.

It turns out that.

After studying the problems and manufacturing methods of such name plate materials, we found that the reason why name plate materials with excellent surface characteristics cannot be obtained is due to the following reasons.

(1) In order to increase the surface gloss, it is necessary that the hardness of the material is high. The lubricating oil is forced into the rolled material, causing minute surface defects (usually called oil pits).

) is likely to be formed, and this phenomenon is especially true when the rolled material is made into a soft material by annealing.

Therefore, it is not preferable to perform annealing before or during cold rolling.

(2) The main causes of surface streak pattern formation are a coarse macrostructure and roll rotation transfer. In order to reduce this roll rotation transfer, the roll roughness of the hot finishing mill should be set to 2μRa or less,
Furthermore, rolls of a cold rolling mill with progressively coarser grains (however,
This can be achieved by changing the roughness from one (fine than the roughness of the hot rolling roll) to one finer.

(3) Normally, in order to make the macrostructure fine, the initial stage of hot rolling is at least cold rolling with a modulus of at least 50, followed by annealing and complete recrystallization, so that individual crystal grains are smaller than the initial crystal grains. The orientation is completely random, and the macrostructure is fine.

However, this method cannot be used because the surface gloss deteriorates as described above.

(4) The main reason for the formation of the macrostructure is as explained below. That is, recrystallization during hot rolling is dynamic recrystallization, and recrystallization occurs one after another with a small processing rate, so individual crystals Even if the grains are fine, they collectively have a very close relationship with the orientation of the crystal grains at the initial stage of hot rolling.

When etching is performed using a NaOH solution or the like, the crystal grain size at the initial stage of hot rolling is exposed, and this is called a macrostructure.

Since the structure of the ingot has a great influence on the crystal grains at the initial stage of hot rolling, the structure of the ingot needs to be uniform or fine.

(5) In order to satisfy all of the above requirements, the hot-rolled material must: (1) have a uniform and fine macrostructure; (2) have a small surface roughness; It is absolutely necessary that the hardness be dog.

As is clear from the detailed explanation above, the present invention (1) makes the macrostructure fine by finely recrystallizing the surface by hot rough rolling, and (2) makes the surface fine by hot finishing rolling. (3) By setting the temperature at a low temperature that does not allow recrystallization, the surface hardness at the end of hot rolling can be improved, the occurrence of oil pits in the first pass of cold rolling can be suppressed, and the surface gloss can be improved. AI for name plates that reduces roll rotation transfer and streaks by reducing roll roughness.
This is a method of manufacturing a board.

The method for manufacturing the AI plate for name plates according to the present invention is as follows: (1) FeO, 1 to 0.8 wt%, Ti 0.003 to 0
．． 08wt% and Si content of 0.2w
After soaking the Al ingot consisting of residual AI and unavoidable impurities at 450 to 600°C for 1 to 48 hours, the hot rough rolling end temperature was adjusted to 440 to 500°C.
℃, the hot rough rolling end temperature is 350 to 420°C, and the rough rolling final pass reduction rate is 40 coefficients or more, and hot rough rolling is performed until the plate thickness is 10 to 30 mm, and then the hot finish rolling end temperature is 350 to 420°C.
20℃ or less, roll roughness of final rolling mill 2μR
The first invention is a method for producing an AI plate for a name plate, which is characterized in that hot finish rolling is carried out at less than or equal to a.
0.003-0.08wt%, 80.0002-0.0
2wt% and Si content of 0.2w
After soaking the Al ingot consisting of the remaining AI and unavoidable impurities at 450 to 600°C for 1 to 48 hours, the hot rough rolling start temperature was set to 440 to 50°C.
Hot rough rolling is performed at 0°C, hot rough rolling end temperature of 350 to 420°C, final rough rolling pass reduction rate of 40 inches or more until the plate thickness is 10 to 30 plates, and then hot finish rolling end temperature is 350 to 420°C.
20℃ or less, roll roughness of final rolling mill 2μR
A second invention provides a method for manufacturing an AI plate for name plates, characterized in that hot finish rolling is carried out as below a.
This invention consists of two inventions.

The method for manufacturing an AI plate for name plates according to the present invention (hereinafter also simply referred to as the method according to the present invention) will be described.

First, Al used in the method for manufacturing an AI plate for name plates according to the present invention will be explained.

Fe is an element that improves strength and refines crystal grains when used as a name plate, but the content is 0.1 wt.
If the content is less than 4, this effect will be small, and if the content exceeds 0.8 wt%, it will be colored during alumite treatment and the alumite processability will deteriorate.

Therefore, the Fe content ranges from 0.1 to 0.8 w.

Si is an element that is unavoidably contained as an impurity, but if the content exceeds 0.2 wt%, alumite workability deteriorates like Fe.

Therefore, the Si content is regulated to 0.2wt1 or less.

Ti and B are elements that are included to refine the structure of the ingot, but if the Ti content is less than 0.003 wt% and the B content is less than O,0002 wt%, this effect will not occur, and
If the Ti content exceeds 0.08wt or 0.01wtq6, this effect will be saturated and there will be no point in including it.

Therefore, the Ti content is 0.003 to 0.08wt, B
The content is 0.0002 to 0.01 wt%.

Note that when containing Ti, an Al-Ti alloy may be used, and when containing Ti and B at the same time, A-Ti alloy may be used.
l-Ti-B alloy is used.

Other impurities include Cu, Mn, Mg, etc. Although these elements are unavoidably contained, they may each be contained in amounts of 0.0 to the extent that they do not impair the effects of the method according to the present invention.
Containment of up to about 5 wt% is permitted.

Next, soaking treatment, hot rough rolling, and hot finish rolling in the method for manufacturing an AI plate for name plates according to the present invention will be explained.

In the method according to the present invention, the ingot is soaked before hot rough rolling.
b If the soaking temperature is less than 450°C and the soaking time is less than 1 hour, the soaking effect will not be sufficient, recrystallized grains will become coarse and the macrostructure will become coarse; If the soaking time exceeds 48 hours, a significant soaking effect cannot be expected.

After completion of this homogenization heating, hot rough rolling start temperature 440-5
Start rough rolling in the range of 00°C, and continue hot rough rolling for 10 to 3
The hot rough rolling is completed at a finishing temperature of 350 to 420°C until the plate thickness reaches 0 plates, and the hot finishing rolling is finished at a hot finishing rolling finishing temperature of 320°C or lower.

Therefore, during hot rolling at a high temperature higher than the recrystallization temperature, the surface layer of the AI rolled material is rolled while repeating rolling and recrystallization in each pass. rate will be lower.

That is, in the case of hot rolling, coarsening of recrystallization is suppressed at a relatively low temperature.

Therefore, the starting temperature for hot rough rolling must be 500°C or lower, and if it is too low, subsequent hot rolling will be difficult, so the lower limit of the hot rough rolling starting temperature is 440°C.
Therefore, the hot rough rolling start temperature is 440
The temperature should be in the range of ~500°C.

In addition, this hot rough rolling is finished with a plate thickness of 10 to 30 mm, but in order to make the recrystallized grains in the surface layer fine at this point and to make the macrostructure fine, the hot rough rolling is finished with a thickness of 10 to 30 mm. It is necessary to set the rolling reduction ratio of the pass to 40 factors or more, and to set the hot rough rolling end temperature to a temperature slightly higher than the recrystallization temperature of AI to prevent coarse recrystallization.

Furthermore, since recrystallization is not performed after hot rough rolling, in order to prevent the structure from becoming long, it is desirable that the plate thickness at the end of hot rough rolling is thin, and is preferably 30 plates or less.
It is desirable that the lower limit is 10 mm because of the need to perform the next hot finish rolling.

Further, since it is better to have a higher working rate even if only a little, the rolling reduction rate in the final pass of hot rough rolling needs to be at least 40 factors or higher.

Next, if the finishing temperature of hot rough rolling is less than 350°C, the temperature is too low and a stable and uniform structure cannot be obtained;
If the temperature exceeds 0°C, the recrystallized grains become coarse.

Furthermore, hot finishing rolling is completed at a temperature of 320° C. or lower so as not to cause recrystallization of the material that has been rough hot rolled.

In this case, at temperatures exceeding 320°C, recrystallization may occur partially during hot finish rolling, and the macrostructure tends to become unrestricted.

The lower the finish temperature of hot finish rolling, the greater the surface hardness of the material after hot rolling.

Further, the roll roughness of the rolling mill at the final stage of hot finish rolling is 2 μRa or less, and the finer the roughness, the smaller the surface roughness of the hot rolled material.

An embodiment of the method for manufacturing an At plate for name plates according to the present invention will be described.

Example 1 The AI shown in Table 1 (refined ingot structure ν* ingot) was face-milled to 360 mm FN and heated at 540°C x 4 hours.
Homogenization heating was performed.

Next, hot rolling was performed in the steps shown in Table 2 (roll roughness in the final stage of hot finish rolling was 1 μRa).

). In addition, cold rolling was performed at 0.8 mmt to obtain a name plate product.

As is clear from Table 2, as shown in A1, the hot rough rolling end temperature deviates from the temperature in the method according to the present invention, so the crystal grains at the end of rough rolling become coarse and the macrostructure deteriorates. It becomes coarse and unsuitable for name plate material, and if the finishing temperature of hot finish rolling is high as in A4, the hardness decreases and oil pits occur, resulting in poor surface gloss and name plate material. It is not suitable as a plate material.

Therefore, 16.2, A according to the method according to the invention
3 has a fine grain size at the end of hot rough rolling, and
The surface gloss and macrostructure of the product are good for use as a nameplate material.

Example 2 Al having the composition shown in Table 3 (refined ingot structure)
The ingot was face-milled to a thickness of 460 mm and heated at 480°C x 4
Homogenization heating of Hr was performed.

Next, hot rough rolling and hot finishing rolling were carried out in the steps shown in Table 4 (roll roughness was 1 μRa).

), and then cold rolled to a thickness of 0.5 mm to obtain a name plate material.

As can be seen from Table 4, when the plate thickness after hot rough rolling is as thick as No. 8, the macrostructure** deteriorates, making it unsuitable as a name put material.

However, in the present invention, the maintenance method A 5 , 116.6,
No. 16.7 has good surface gloss and macrostructure as a nameplate material.

Example 3 AI with the composition shown in Table 5 (refined cast structure)
The ingot was side-faced to a thickness of 560.0, and the thickness was 560'C x 12H.
Homogenization heating was performed at r.

Then, after hot rolling was performed in the heat treatment step shown in Table 6 (roll roughness at the final stage of hot rolling was 1 μRa).

), cold rolled to 0.6 mm and made into a name plate material.

As is clear from this Table 6, 16.9, A 1
If the hot rough rolling start temperature is higher than the method according to the present invention, as in the case of 0, the macrostructure becomes coarse, and the flatness 110,
When the rolling reduction ratio in the final pass of hot rough rolling is lower than that of the method according to the present invention, as in AI2, the macrostructure becomes coarse, and both are unsuitable as nameplate materials.

However, the AI'10 nameplate material produced by the method according to the present invention has good surface gloss and macrostructure, and is suitable as a nameplate material.

Example 4 AI with the composition shown in Table 7 (refined cast structure)
The ingot was turned face side to a thickness of 460℃mn, and heated to 520℃
Homogenization heating was performed for 8 hours.

Next, hot rough rolling and hot finish rolling were performed under the conditions shown in Table 8, and then cold rolling was performed to a thickness of 0.5 mm to obtain a name plate material.

** As is clear from this Table 8,
When the roughness of the final hot rolling roll is 2 μRa or less, there are few streaks and a good surface gloss, making it suitable as a name plate material (A, 13).

However, when the roll roughness is 2 μRa or more, such as Al 4 and A15, many streaks occur, making the material unsuitable as a name plate material.

Example 5 Al having the composition of 116.16, A17 shown in Table 9
Cast the ingot, and A16 is A I-5 w t %
The ingot crystal grains were refined using an intermediate master alloy of T i -0 and 2wt%B.

These ingots were turned face side to a thickness of 460 mm and heated to 510°C.
Homogeneous preliminary heating was performed for X 6 Hr, then hot rough rolling was started at 480°C, and the rough rolling final pass reduction rate was 50%.
The plate was finished to a thickness of 30 mm at 420°C, and then hot finish rolling was completed at 300°C at 4.5 rrrrrn.

In addition, the roll roughness of the final stage rolling mill for hot finishing is 1μ.
It was set as Ra.

Next, cold rolling was performed to a body thickness of 0.5 to obtain a name plate material.

The evaluation of these nameplate materials is shown in Section **10.
Shown in the table.

It is clear from Table 10 that the effect of refining the ingot by the Al-Ti-B intermediate master alloy is very large.

As explained above, the name plate A according to the present invention
Since the method for producing I-plates has the above-mentioned configuration, even if the hot-rolled material is cold-rolled, the macrostructure is uniform and fine, the surface gloss is excellent, and the surface streaks are not present. A name plate material with very few patterns can be obtained.

Claims (1)

[Claims] I Fe0.1-0.8wt%, Ti0.003-0
．． 08wt% and Si content of 0.2w
After soaking the Al ingot consisting of the remaining AI and unavoidable impurities at 450 to 600°C for 1 to 48 hours, the hot rough rolling start temperature was adjusted to 440 to 500°C.
℃, the hot rough rolling end temperature is 350 to 420°C, and the rough rolling final pass reduction rate is 40% or more to perform hot rough rolling until the plate thickness is 10 to 30 plates, and then the hot finish rolling end temperature is 32
0℃ or less, roll roughness of final rolling mill 2μRa
A method for producing an Al plate for name plates, which comprises performing hot finish rolling as follows. 2 FeO,: 1~0.8wt%, Ti0.003~
0.08wt%, BO,0002~0.02wt%
In addition, the Si content is regulated to 0.2 wt% or less, and the Al ingot consisting of the remaining AI and unavoidable impurities is subjected to soaking treatment at 450 to 600°C for 1 to 48 hours, and then hot rough rolled. Hot rough rolling is performed until the plate thickness is 10 to 30 mm at a starting temperature of 440 to 500°C, a hot rough rolling end temperature of 350 to 420°C, and a reduction rate of 40% or more in the final pass of rough rolling, followed by hot finishing rolling. The end temperature is 320℃ or less.
Finish Rolling A method for producing an Al plate for a name plate, characterized in that hot finish rolling is performed with a roll roughness of 2 μRa or less in a final rolling mill.