JPH0665422B2 - Manufacturing method of modified cross-section strip - Google Patents

Description

Description: BACKGROUND AND OBJECT OF THE INVENTION The present invention relates to a method for producing a strip having a portion having a varied plate thickness in the width direction continuously in the longitudinal direction, a so-called irregular cross-section strip by rolling. Is.

In the case of producing a modified cross-section strip by a rolling method, a method of rolling a flat strip material having the same plate thickness by partially changing the rolling reduction force was used, but this method deforms depending on the magnitude of the rolling reduction force. The amount varies depending on the parts in the width direction, and this difference in the amount of deformation appears as a difference in elongation in the rolling direction of the strip, causing uneven deformation and causing twisting of the strip. Was there.

As a method of preventing the twist of the rolled strip, a lateral rolling method or a tenter rolling method has been used in which the amount of deformation during rolling is released in the width direction of the strip. However, in the case of the horizontal rolling method, since the rolling is performed in the width direction orthogonal to the longitudinal direction of the strip, the workability is poor and the productivity cannot be increased.

On the other hand, the tenter-rolling method is a method of extruding with a combination of a V-shaped die and a roll to deform in the width direction of the strip, so that the forming process is performed intermittently and Since it is a method of generating a pressing force by reciprocating motion, there are drawbacks such that the processing speed cannot be increased and the improvement of production efficiency cannot be attempted.

Therefore, an object of the present invention is to eliminate the drawbacks in the prior art as described above, and to manufacture a modified cross-section strip without twisting.
Another object of the present invention is to provide a manufacturing method by a rolling method that can realize excellent productivity.

[Summary of the Invention] In order to achieve the above object, in the present invention, rolling is performed by applying a rolling force only to a portion of the material to be processed into a thin plate thickness by using the grooved roll, Buckling deformation of the portion located in the groove into the groove, rolling the buckled portion of the deformed material to a flat surface, and rolling the rolled material into a thick-walled portion with a reduction ratio of the thick-walled portion. Rolling reduction to be greater than and less than 5% of the rolling reduction of.

In this case, the number of passes in each step is appropriately selected according to the plate thickness and width of the raw material, the desired width direction plate thickness difference, and the like. However, an intermediate treatment such as annealing may be inserted between the steps for adjusting the hardness.

The reason why the reduction ratio is specified in the finish rolling of the present invention is as follows.

In order to prevent the occurrence of corrugated defects in the thin portion, it is desirable that the thick portion and the thin portion have the same rolling reduction. This point has already been proposed as Japanese Patent Application No. 57-46595.

According to the experiments conducted by the inventors, a product having no defect can be obtained even if the rolling reduction of the thick portion is somewhat large. However, when the difference from the rolling reduction of the thin portion is larger than 5%, the thin portion of the product has rough skin. It was found that a defect due to For these reasons, in the present invention, the rolling reduction of the thick portion is limited to be larger than the thin portion in the range of less than 5%.

Examples of the metal material applicable to the method of the present invention include materials including copper, copper alloys, aluminum, non-ferrous metals including aluminum alloys, iron, steel, and the like, and composite materials including combinations thereof.

[Embodiment] The present invention will be described below with reference to the drawings. As shown in FIG. 1, a flat plate-shaped material 1 having a predetermined width sequentially passes through at least three sets of rolls 2, 3 and 4. By this, the cross-section strip 15 is formed.

As shown in FIG. 2, the first set of rolls 2 is constituted by a grooved roll 21 having at least one groove portion 22. The material 1 is the grooved roll 21 and the flat roll 2
By passing between 3 and the center of the groove 22,
The part to be thinned in the width direction is the grooved roll 21.
Is machined between the groove 22 and the surface defining the groove 22. At this time, most of the material flow due to the deformation of the thin portion 11 moves to the portion 12 side where no pressing force is applied, and is buckled and deformed in the groove 22 to be absorbed. Therefore, even if there is a thickness difference in the width direction, there is no difference in the elongation in the rolling direction,
The material 13 does not deform in a wavy shape after rolling.

In this case, the groove portion 22 does not necessarily have to have a semicircular cross section, and it is sufficient that the groove portion 22 has a space in which the material can be deformed and buckled, and the cross sectional shape may be rectangular, trapezoidal, or the like.

The second set of rolls 3 for rolling the deformed material 13 comprises a pair of flat rolls. Therefore, the raw material 13 is flattened at the portion 12 by passing through the roll 3 and becomes a raw material 14 having a cross section close to the product as shown in FIG. In this case, the upper and lower surfaces of the thick portion do not have to be completely flat, and the thickness may be reduced to some extent.

The raw material 14 is then passed through the third set of rolls 4 in order to finish the shape of the change in plate thickness to a predetermined size. As shown in FIG. 4, this roll has a grooved roll 41 and a flat roll 4 each of which has a stepped groove portion 42 having a cross section substantially equal to the product cross section.
2, the rolling reduction of the thick portion is larger than that of the thin portion in the range of less than 5% corresponding to the plate thickness ratio of the material 14 in the width direction. Therefore, the material 14
By passing through the roll 4, the sheet is prevented from being roughened, is stretched in the longitudinal direction or the rolling direction without roughening the surface, and is finished into a predetermined cross-sectional dimension to become a product 15.

By the way, a copper plate having a thickness of 2.0 mm and a width of 46 mm is provided with a grooved roll 21 having a semicircular cross-section groove 22 having a diameter of 25 mm and a flat roll 2.
No. 3 was used to perform rolling around the groove 22 to make the thin portion have a thickness of 0.6 mm (pressure reduction 70%).
The thin-walled portion 11 was flat without waving. Next, the portion 12 is rolled until its upper and lower surfaces are parallel, and further, the material 14 is rolled using a grooved roll 41 to obtain a deformed portion having a thick portion having a thickness of 1.2 mm and a thin portion having a thickness of 0.38 mm. Although the cross-section strip 15 was finished (difference of reduction ratio 3.3%), not only the corrugation of the thin wall portion but also the twist of the entire strip was not observed.

As another example, the strip 15 obtained in the above example is
Annealed at 0 ° C for 30 minutes and rolled, then the thickness of thick part is 1.0
mm, thin section 0.33 mm thick modified cross-section strip (difference in rolling reduction 3.5%), but like the previous example, no waviness or twisting is seen and the surface quality is excellent. You got what you got.

In addition, using the grooved roll 41, the material 14 obtained in the previous example has a thick portion with a thickness of 1.1 mm and a thin portion with a thickness of 0.37.
finished to mm. In this case, since the rolling reduction of the thick portion was 6.6% larger than the rolling reduction of the thin portion, the surface of the thin portion was roughened and the surface quality was deteriorated.

The thick part is 1.0 mm thick and the thin part is 0.2 mm thick.
When finished to 8 mm, the pressure reduction ratio of the thick portion was 3.3% smaller than that of the thin portion, so waviness and twisting occurred in the thin portion, and a normal rolled material could not be obtained.

Although the previous example shows a case of a modified cross-section strip in which the thick-walled portion projecting to one surface side is arranged in the center, it is also possible to arrange grooved rolls on both sides to form a shape in which both surfaces project. it can. Of course, the number and positions of the groove portions of the grooved roll may be changed to form desired cross-sectional shapes having different numbers and positions of thick-walled portions.

[Effects of the Invention] As described above, according to the present invention, after the rolling is performed without performing the reduction to the thick portion, the reduction ratio of the thick portion is less than 5% as compared with the thin portion. Since it is a method of rolling so that it will be large in the range, stable groove roll rolling is possible without roughening the surface of the product, it is possible to obtain irregular cross-section strips as efficiently as normal roll rolling, and chips are removed. It is advantageous in that it is possible to provide a modified cross-section strip having excellent surface performance at a low cost without wasting material such as generation, and has a great industrial value.

[Brief description of drawings]

FIG. 1 is an explanatory view showing one embodiment of the method according to the present invention, and FIGS. 2 to 4 are explanatory views showing the state of each rolling in the example of FIG. 1, 13 and 14: material, 2, 3 and 4: roll, 21
And 41: grooved rolls, 22 and 42: groove portions, 11: thin portion, 12 thick portion.

Claims (1)

[Claims] 1. A method for producing a modified cross-section strip having portions having different plate thicknesses in the width direction continuously in the longitudinal direction by a rolling method, comprising at least the following steps. a) A work roll having at least one of which is a grooved roll is rolled by applying a reduction force only to a portion where the plate thickness in the width direction of the material is to be thinned, and the portion of the material located in the groove portion of the grooved roll is Buckling deformation into the groove, b Rolling the buckled part of the deformed material flat, c Rolling the material with the buckled part flattened, the reduction force of the thick part reduces the thin part A step of rolling so as to be greater than the force and less than 5%.