JPH09253711A - Manufacture of aluminum clad material having uniform clad ratio - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the manufacturing method of an aluminum clad material having a uniform clad ratio by suppressing dropping of the clad ratio in the end part of the clad material. SOLUTION: In this manufacturing method, at the time of rolling a three-layer clad material consisting of aluminum materials having different deformation resistance, hot rough rolling is executed while increasing the deformation resistance by cooling the surfaces of claddings. In such a case, in the stage where the ratio of the diameter of roll to the thickness of the clad material is within 15 or the ratio of the width of the clad material to the thickness of the clad material is within 15, rough rolling is executed after cooling the surface of the claddings with cooling water, rolling oil or the like, or the hot rough rolling is executed while repeating the cooling and the hot rough rolling. Furthermore, at the time of cooling the surfaces of the claddings with the cooling water, the rolling oil or the like, the hot rough rolling is executed while the ratio ΔT(%) of the drop amount of the surface temp. of the claddings to the initial temp. of the surface of the claddings is regulated within the range of 20-80%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for manufacturing a three-layer clad material made of an aluminum material and an aluminum alloy material (hereinafter referred to as an aluminum material), and more particularly to a hot rough rolling technical field of the three-layer clad material. It is a thing.

[0002]

2. Description of the Related Art In general rolled materials, there is a technique for imparting a uniform temperature distribution in the sheet width direction between hot rough rolling and hot finish rolling. This is to reduce the time it takes for the rolled material to cool to the prescribed temperature at the start of hot finish rolling, and to heat the plate edge, which has a lower temperature than the plate center, to make the material of the plate uniform. It is a technology that aims to improve the dimensional accuracy in finish rolling. After the hot rough rolling is finished, the central part of the rolled material is cooled to make the temperature uniform,
A uniform cooling method for a thick plate controlled rolling material which starts hot finish rolling is disclosed in JP-A-61-238413.

However, according to the above method, it is not possible to reduce the widthwise expansion (width expansion) of the laminated material surface layer portion in the hot rough rolling of the three-layer clad material made of aluminum materials having different deformation resistances. It is not possible to suppress a decrease in the clad ratio at the material end. For this reason, the present situation is that after the hot rolling, the portion of the clad material end portion where the clad ratio is reduced is cut off. Here, the clad ratio is the ratio (percentage) of the thickness of the laminated material to the total thickness of the clad.

[0004]

As described above, by simply making the temperature distribution uniform in the width direction of the clad material, the three-layer clad material made of aluminum materials having different deformation resistances can reduce the clad ratio at the edge of the clad material. The decline cannot be suppressed. FIG. 6 shows an example of changes in the clad ratio in the width direction of the three-layer clad material rolled by the usual rolling method. FIG. 6 shows the relationship between the dimensionless clad material 1/2 width and the ratio of the clad ratio after rolling to the set clad ratio. As shown in the figure, the clad ratio decreases when the width of 1/2 clad material exceeds 0.6. This is because the laminated material surface layer portion extends in the width direction during hot rough rolling.

The present invention, in the initial stage of hot rough rolling of a three-layer clad material made of aluminum materials having different deformation resistances,
By cooling the surface of the laminated material to increase the deformation resistance of the laminated material, especially the deformation resistance of the edges of the laminated material width, and evenly deforming in the width direction of the clad material, and suppressing the expansion of the width of the surface layer of the laminated material. An object of the present invention is to provide a method for manufacturing an aluminum clad material having a uniform clad ratio that suppresses a decrease in the clad ratio at the clad material end portion.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is to perform hot rough rolling while rolling a three-layer clad material made of aluminum materials having different deformation resistances while cooling the surface of the laminated material to increase the deformation resistance. In the above hot rough rolling, the ratio of roll diameter to clad material thickness (roll diameter / clad material thickness) is within 15 or clad material width to clad material thickness (clad material width / clad material width Material thickness)
Within 15 stages, the surface of the laminated material is cooled with cooling water, rolling oil or the like and then hot rough rolling is performed, or hot rough rolling is performed by repeating the cooling and hot rough rolling.

Further, when the surface of the above-mentioned composite material is cooled with cooling water or rolling oil, etc., the ratio of the decrease amount of the composite material surface temperature to the initial temperature of the composite material surface (the decrease amount of the composite material surface temperature / the initial temperature of the composite material surface) ) ΔT (%) is in the range of 20 to 80% and hot rough rolling is performed to produce an aluminum clad material having a uniform clad ratio.

The change in the clad ratio in the width direction of the clad material as shown in FIG. 6 is caused mainly by the extension in the width direction during the hot rough rolling of the edges of the laminated material. In the initial stage of hot rough rolling, the clad material thickness is thicker than the clad material width, and it is difficult for the rolling reduction force to reach the central part of the clad material thickness. The end portion is extended and widened, and the clad ratio at the end portion of the clad material is reduced. In other words, by making such a non-uniform deformation in which the edge portion of the surface layer portion of the laminated material preferentially deforms close to the deformation method in which the deformation reaches the central portion of the thickness of the cladding material, It is possible to suppress a decrease in the clad ratio. As a method of this, the deformation resistance of the surface layer of the laminated material is cooled by cooling the surface of the laminated material so that the central portion of the thickness of the clad material is easily deformed and the width of the edge of the surface layer of the laminated material can be suppressed. To increase. Further, by increasing the deformation resistance of the surface layer of the laminated material so that the deformation can reach the central portion of the thickness of the cladding material, the shear stress at the interface between the laminated material and the base material can be reduced.

As described above, in order to easily deform to the central portion of the thickness of the cladding material and to suppress the width expansion of the edge portion of the surface layer portion of the laminated material, the edge portion of the laminated material surface layer is The ratio of roll diameter to clad material thickness (roll diameter / clad material thickness), which is a range that easily extends in the width direction, is within 15 or the ratio of clad material width to clad material thickness (clad material width /
When the clad material thickness is 15 or less, the surface of the laminated material is cooled and hot rough rolling is performed.

FIG. 7 shows the ratio ΔT (%) between the amount of decrease in the temperature of the surface of the composite material and the initial temperature of the surface of the composite material and the set clad at the position where the clad ratio decreases most when hot rough rolling is performed without cooling. It is a diagram showing the relationship between the ratio of the clad ratio after rolling to the ratio, and it can be seen that the decrease in the clad ratio decreases as ΔT increases. The reason why ΔT is limited to the range of 20 to 80% is as follows. This is because when ΔT is less than 20%, the surface temperature of the laminated material immediately returns to the temperature before cooling due to the heat recovery during the hot rough rolling, and the cooling effect is small. Therefore, ΔT is limited to 20% or more. Moreover, even if ΔT exceeds 80%, the increase in the cladding ratio is saturated. Therefore, ΔT is limited to 80% or less. The rolling conditions in Fig. 7 are as follows: initial clad material width 1000 mm, initial clad material thickness 550 m
m, roll diameter 1000mm, initial temperature of the surface of the laminated material is 400 ℃
Therefore, the amount of reduction per pass for the clad material thickness of 550 mm to 70 mm is 60 mm.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

Example 1 An embodiment of the present invention will be described below. 4000 series aluminum material for the clad material and 30 for the base material
Using 00 series aluminum material, with a set clad ratio of 15%,
A rolled material with an initial clad material width of 1000 mm and an initial clad material thickness of 550 mm was manufactured. The initial temperature of the rolled material was 400 ° C, and hot rough rolling was performed with a reverse mill having a roll diameter of 1000 mm.
As the pass schedule, a clad material thickness of 550 mm to 70 mm was rolled in 8 passes with a reduction amount of 60 mm per pass. At this time, the ratio of roll diameter to clad material thickness is 2 to 12.5, the ratio of clad material width to clad material thickness is 2 to 12.5, and ΔT is 42.
%. Cooling of the clad rolled material during hot rough rolling was performed by cooling the entire surface of the laminated material with cooling water at 20 ° C. for 10 seconds each on the inlet side and the outlet side of the roll, as shown in FIG.
The relationship between the temperature of the laminated material and the base material and the deformation resistance is shown in FIG. As a comparative example, hot rough rolling without cooling was also performed.

After hot rough rolling, the length direction of the clad is 1/4.
The shape of the cross section in the width direction was observed at the position. The result is shown in FIG. Fig. 3 shows changes in cross-sectional shape in the width direction for the dimensionless clad material width and the dimensionless clad material 1/2 thickness. As is clear from the figure,
When the surface of the laminated material is cooled, the central portion of the thickness of the clad material squeezes out in the width direction, and the width of the surface layer of the clad is less widened. From this, it can be seen that by cooling the surface of the laminated material and performing rough hot rolling, it is possible to suppress the width expansion of the clad surface layer portion and to deform the central portion of the clad material thickness.

Similarly, after the hot rough rolling, the change of the clad ratio in the width direction was investigated at the position of 1/4 in the length direction of the clad. FIG. 4 shows the results. Figure 4 shows the change in the cladding ratio for the dimensionless clad material 1/2 width. As is clear from the figure, the clad ratio decreases toward the width end of the clad material regardless of whether or not the surface of the clad material is cooled. However, it can be seen that when the surface of the laminated material is cooled, the decrease in the clad ratio after the clad width exceeds 0.6 is small. As shown in FIG. 2, this is because the surface of the laminated material is cooled in a temperature range in which hot rough rolling is performed, that is, a temperature range in which there is no difference in deformation resistance between the laminated material and the base material, and the deformation resistance of the laminated material is increased. Then, the effect of performing the hot rough rolling appears.

Now, the allowable range of the clad ratio is ± 1.5%
(13.5 to 16.5%), in the method of the present invention, the total width of the clad material satisfies the allowable range of the clad ratio, while in the comparative example (without cooling), the clad material width of 0.85 satisfies the allowable range of the clad ratio. Become. Therefore, this difference leads to an improvement in yield. In this embodiment, since the clad material width is 1000 mm, it is possible to reduce the cut-off amount of the clad material piece width of 75 mm and the total width of 150 mm.

Example 2 Example 2 is an example in which the present invention is applied to hot rolling of a sheet.
This is not limited to the clad material, but generally in the hot rough rolling, the plate surface has a widened shape, so this part is cut off in the product. FIG. 5 shows the case where the aluminum material A1100 is rolled to 550 mm to 80 mm under the same conditions as in Example 1 above.
The cross-sectional shape in the width direction is shown. FIG. 5 shows changes in cross-sectional shape in the width direction for the dimensionless plate width and the dimensionless 1/2 plate thickness. As is clear from the figure, by cooling the plate surface, not only the clad material,
Even uniform material can suppress the width expansion of the plate surface layer,
It is possible to reduce the amount of cut-off at the width end of the product after rolling.

[0016]

As is apparent from the above description,
The method for producing an aluminum clad material having a uniform clad ratio according to the present invention is to cool the surface of the composite material at the initial stage of hot rough rolling of the three-layer aluminum clad material to increase the deformation resistance of the composite material, and to increase the clad material width direction. Since it is possible to suppress the width widening of the end portion of the surface layer portion of the laminated material by uniformly deforming it, it is possible to obtain an aluminum clad material having a uniform clad ratio in the width direction of the clad material. Therefore, the present invention can also reduce the amount of cut-off of the end portion of the clad material after hot rolling.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a method for cooling a clad rolled material during hot rough rolling.

FIG. 2 is a diagram showing a relationship between temperature and deformation resistance of a laminated material and a base material.

FIG. 3 is a quarter length direction of the clad material in Example 1.
It is a figure which shows the width direction cross-sectional shape of the position of.

FIG. 4 is a quarter length direction of the clad material in Example 1.
It is a figure which shows the change of the clad ratio of the position of the width direction.

FIG. 5: Aluminum material A1100 under the same conditions as in Example 1
It is a figure which shows the width direction cross-sectional shape at the time of hot rough rolling to 550 mm-80 mm.

FIG. 6 is a diagram showing the relationship between the dimensionless clad material 1/2 width and the ratio of the clad ratio after rolling to the set clad ratio.

FIG. 7 shows the ratio ΔT (%) of the decrease amount of the surface temperature of the composite material to the initial temperature of the composite material surface at a position where the clad ratio decreases most when hot rough rolling is performed without cooling with respect to the set clad ratio. It is a figure which shows the relationship with the ratio of the clad ratio after rolling.

[Explanation of symbols]

1 ... Rolled material, 2 ... Laminated material, 3 ... Base material, 4 ... Roll, 5
… Header, 6… Cooling water.

Claims (3)

[Claims] 1. When rolling a three-layer clad material made of aluminum materials having different deformation resistances, hot rough rolling is performed while cooling the surface of the laminated material to increase the deformation resistance. Manufacturing method of aluminum clad material. 2. In the hot rough rolling, the ratio of roll diameter to clad material thickness (roll diameter / clad material thickness) is 15
Within, or when the ratio of clad material width to clad material thickness (clad material width / clad material thickness) is 15 or less, the surface of the laminated material is cooled with cooling water or rolling oil, and then hot rough rolling is performed. Alternatively, the method for producing an aluminum clad material having a uniform clad ratio according to claim 1, wherein the hot rough rolling is performed while repeating the cooling and the hot rough rolling. 3. When cooling the surface of the composite material with cooling water, rolling oil, or the like, the ratio of the decrease amount of the surface temperature of the composite material to the initial temperature of the composite material surface (the amount of decrease in the surface temperature of the composite material / the initial temperature of the composite material surface). The method for producing an aluminum clad material having a uniform clad ratio according to claim 2, wherein hot rough rolling is performed with ΔT (%) in the range of 20 to 80%.