WO2012169781A2

WO2012169781A2 - Apparatus for asymmetric processing, method for asymmetric processing, and processed material manufactured using same

Info

Publication number: WO2012169781A2
Application number: PCT/KR2012/004469
Authority: WO
Inventors: 정효태; 최병학; 김동민
Original assignee: 강릉원주대학교 산학협력단
Priority date: 2011-06-07
Filing date: 2012-06-07
Publication date: 2012-12-13
Also published as: WO2012169781A3; KR101274504B1; KR20120135695A

Abstract

The present invention aims to provide an apparatus for asymmetric processing and a method for asymmetric processing using same for enhancing material properties, such as moldability, by controlling the texture of a base material. According to one aspect of the present invention, an extruded material is pushed through a dice having asymmetric extrusion holes with respect to a flat surface direction of the extruded material, so that the extruded material is extruded by inducing shearing deformation on the inside of the extruded material in the widthwise direction thereof, thereby forming the extruded material. Using the extruded material as a rolled material, a rolled material is pushed through between first rolls and second rolls having different diameters, so that the rolled material is rolled by inducing shearing deformation on the rolled material force, thereby forming the rolled material.

Description

Asymmetrical processing apparatus, asymmetrical processing method and processed materials manufactured using the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a material, and more particularly, to an asymmetric processing apparatus and processing method for improving material properties such as formability of a processed product by controlling the texture of a workpiece.

In order to process the metal member in the form of a plate or the like having a predetermined standard, a rolling or extrusion process is generally performed. As the volume of the base material changes in the processing, the microstructure inside the base material also changes accordingly. It is known that the texture of a material has a great influence on material properties, such as formability, such as the mechanical properties of the material. Usually, the metal material has an inherent slip system according to its crystal structure, and the moldability of the metal material can vary depending on whether or not the slip system is operated. Whether such a slip system works is largely related to the texture of the metal material.

However, according to the conventional symmetrical extrusion method or rolling method, it is difficult to control the texture of the base metal to improve its formability.

Accordingly, the present invention has been made to solve the above-described problems, to provide a processing apparatus and a processing method capable of controlling the aggregate structure, and to provide a processing material in which the aggregate structure is controlled by such an apparatus and method. . The foregoing problem has been presented by way of example, and the scope of the present invention is not limited by this problem.

An asymmetric processing method according to one aspect of the present invention is provided. The extruded material is manufactured by extruding the extruded material by pushing the extruded material through a die having an extrusion hole having an asymmetrical shape with respect to the plate surface direction of the extruded material and inducing shear deformation therein in the thickness direction of the extruded material. Using the extruded material as a rolled material, the rolled material is rolled by pushing the rolled material between the first and second rolls having different diameters while inducing shear deformation force on the rolled material.

In the step of manufacturing the extruded material, the extrusion hole of the die includes a tapered portion whose width is varied along the extrusion direction of the extruded material, the tapered portion has an asymmetrical shape with respect to the plate surface direction of the extruded material It may be arranged to have.

The manufacturing of the rolled material may include shearing applied to any one of the first and second surfaces of the rolled material by the first roll by controlling rotational angular velocities of the first and second rolls differently from each other. The rolled material can be rolled by controlling the deformation force and the shear deformation force applied to any one of the first and second surfaces by the second roll to be different from each other.

The manufacturing of the rolled material may be performed by rolling the rolled material while maintaining the rotational linear velocity of the first roll and the second roll.

The manufacturing of the rolled material may include setting the first roll to apply the shear deformation force to the first surface and the second roll to apply the shear deformation force to the second surface, thereby continuously performing the rolled material two or more times. Rolling may be included.

The manufacturing of the rolled material may include rolling the rolled material at least once by changing a surface to which shear strain is applied from the first and second rolls of the rolled material.

The manufacturing of the rolled material may include rolling the rolled material two or more times by setting the rolling direction of the rolled material to be the same.

The manufacturing of the rolled material may include rolling the rolled material at least once by changing a rolling direction of the rolled material.

The manufacturing of the rolled material may be performed by coupling a third roll having a larger diameter than the first roll to the first roll on the opposite side of the second roll to support the first roll. .

According to another aspect of the present invention, an asymmetric processing method is provided. And a tapered portion whose width varies along the extrusion direction of the plate-shaped extrudable material, wherein the tapered portion has an asymmetrical shape with respect to the plate surface direction of the extruded material and the thickness direction of the extruded material. While being spaced apart from the tapered portion and pushed through a die including a first inner surface and a second inner surface facing the first and second surfaces of the extrudate respectively, inducing shear deformation therein in the thickness direction of the extrudate; Extruded material is prepared by extrusion. By using the extruded material as a rolled material, the rolled material is rolled by using one or more work rolls in which a pair of rolling rolls having different diameters rotating at the same rotational linear speed is used.

The manufacturing of the rolled material may be performed by combining a reinforcement roll supporting a rolling roll having a smaller diameter in the work roll to an opposite side of the rolling roll having a relatively larger diameter in the work roll. .

In the manufacturing of the extruded material, the first inner surface and the second inner surface of the die may be arranged to have different inclinations along the extrusion direction to be asymmetric with respect to the plate surface direction of the plate shape.

The cross section of the extrusion hole has a rectangular shape, and the die includes a third inner surface and a fourth inner surface spaced apart from the tapered portion along the width direction of the plate shape, and the third inner surface and the fourth inner surface are the extrusion. It can be arranged symmetrically along the direction.

According to still another aspect of the present invention, there is provided a workpiece manufactured using at least one of the asymmetric processing methods described above.

According to another aspect of the present invention, an asymmetric processing apparatus is provided. A die including a rectangular extrusion hole for extruding the extruded material into a sheet shape, wherein the entry hole includes a tapered portion whose width varies along an extrusion direction of the extruded material, and the tapered portion is the sheet material. An asymmetrical extruder having an asymmetrical shape with respect to the plate direction of the shape is provided. A first roll contacting the first surface of the rolled material by using the extruded material extruded from the asymmetric extruder as a rolled material; A second roll having a larger diameter than the first roll and in contact with a second face that is opposite the first face; And a power providing unit for supplying power to the first roll and the second roll so that the ratio of the rotational angular velocities of the first roll and the second roll can be adjusted.

The power supply unit may include a first motor and a second motor driving the first roll and the second roll, respectively; And a controller capable of controlling rotational angular velocities of the first motor and the second motor.

The asymmetric rolling mill, the first gear connected to the first roll; And a second gear connected to the second roll and coupled with a different gear ratio from the first gear, wherein the power providing unit may include a motor providing a driving force to the first or second gear.

The asymmetric rolling mill may further comprise a third roll having a larger diameter than the first roll and coupled to support the first roll on the opposite side of the second roll.

A first gear connected to the first roll or third roll; And a second gear connected to the second roll and coupled with the first gear with a different gear ratio, wherein the power providing unit includes a motor for transmitting a driving force to the first gear or the second gear. can do.

When using the asymmetric processing method and the asymmetric processing apparatus according to an embodiment of the present invention, it is possible to manufacture a processed material greatly improved material properties such as moldability compared to the prior art. Particularly, in the case of extrusion-rolling a metal material having poor moldability at room temperature, such as a magnesium alloy, according to an embodiment of the present invention, as the slip system is disposed so that shear deformation can occur well at room temperature, excellent room temperature formability which has not been obtained conventionally is obtained. Can have.

The effects of the present invention are not limited to those mentioned above, and other effects that are not mentioned will be clearly understood by those skilled in the art from the following description.

1 is a schematic cross-sectional view of an asymmetric processing apparatus according to an embodiment of the present invention.

2 is a schematic cross-sectional view of an asymmetric processing apparatus according to another embodiment of the present invention.

3A and 3B are front and perspective views of a rolling mill of an asymmetric processing apparatus according to an embodiment of the present invention.

4A and 4B are front and perspective views of a rolling mill of an asymmetric processing apparatus according to another embodiment of the present invention.

5 is a front view of a rolling mill of an asymmetric processing apparatus according to another embodiment of the present invention.

FIG. 6 illustrates a slip system of magnesium having a hexagonal close-packed (HCP) structure.

7 shows an aspect of a dense packed hexagonal tablet arranged inside the rolled material or the extruded material.

FIG. 8 shows the poles of the A, B, C, and D crystals of FIG.

Figure 9 illustrates the (0001) pole figure of the AZ31 alloy rolled by the rolling process of the asymmetric processing method according to an embodiment of the present invention.

10 to 12 show the (0001) pole figure of the AZ31 alloy rolled by the rolling process according to the comparative example.

Figure 13 shows a rolling process of the asymmetric processing method according to another embodiment of the present invention.

FIG. 14 shows the (0001) pole figure of the AZ31 alloy rolled by the rolling process shown in FIG.

15 shows a rolling process of the asymmetric processing method according to another embodiment of the present invention.

FIG. 16 shows the (0001) pole figure of the AZ31 alloy rolled by the rolling process shown in FIG. 15.

17 is a schematic cross-sectional view showing an extruder of an asymmetric processing apparatus according to an embodiment of the present invention.

FIG. 18 is a partially cut away perspective view showing a die of the extruder of FIG. 17.

19 is a plan view of the dice of FIG. 18.

20 is a partially cut perspective view showing a die included in an extruder of an asymmetric processing apparatus according to another embodiment of the present invention.

21 is a cross-sectional view of the dice of FIG. 20.

22 is a (0001) pole figure in the + Z axis direction of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention.

Figure 23 is a (0001) pole figure in the -Z axis direction of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention.

24 is a (0001) pole figure of the AZ31 sheet according to the comparative example.

25 is a true stress-strain graph of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention;

26 is a true stress-strain graph of the AZ31 sheet according to the comparative example;

27 is a graph showing the r-value according to the angle with respect to the tensile axis of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, only this embodiment to make the disclosure of the present invention complete, the scope of the invention to those skilled in the art It is provided for complete information. In the drawings, the components may be exaggerated or reduced in size for convenience of description.

Asymmetric processing apparatus and asymmetric processing method provided through the present invention can be applied to any base material that can be applied to improve the material properties, such as formability, the following examples are intended to illustrate the technical spirit of the present invention.

In embodiments of the invention, the texture may represent a state in which the respective crystalline grains of the polycrystalline material are aligned in a constant direction. In embodiments of the invention, the texture may be referred to as a texture or texture, and its scope is not limited by its name. In the embodiments of the present invention, the texture of the material is used in a relative concept rather than an absolute concept. That is, the fact that a material has a texture in a certain direction means that a large part of the grains of the material have a texture in that direction, and that all the grains of the material have a texture in that direction. It does not mean.

In embodiments of the present invention, the pole figure may represent a picture in the form of a stereoscopic projection showing the direction of distribution of the crystallographic lattice planes in the analysis of crystal orientation or texture of the material. The pole figure can be shown using X-ray diffraction (XRD) analysis.

In the embodiments of the present invention, the rolled material means the object to be rolled and the rolled material means the object to be rolled is changed to the desired shape. Similarly, the material to be extruded means an object to be extruded, and the extruded material means an object to which the material to be extruded is changed into a desired shape. On the other hand, the workpiece refers to a material produced by processing the base material by extrusion, rolling, casting, forging, drawing or a combination thereof, in the present invention may be an extruded or rolled material according to the final processing process.

Referring to FIG. 1, the asymmetric processing apparatus may include an asymmetric extruder 200 and an asymmetric rolling mill 100. The asymmetrical rolling mill 100 may be coupled to the rear end of the asymmetrical extruder 200. Accordingly, the extruded material 250 is processed into the extruded material 260 via the asymmetrical extruder 200, and the extruded material 260 is used as the rolled material 104 to the rolled material 120 via the asymmetrical rolling mill 100. Can be prepared. The rolled material 120 thus manufactured may be primarily processed while passing through the asymmetrical extruder 200, and then may be secondaryly deformed while passing through the asymmetrical rolling mill 100. For example, in the case of sheet processing, it can be processed first into a plate of a predetermined thickness in the asymmetric extruder 200, and then into a plate of a thinner final thickness in the asymmetric mill 100.

The asymmetric extruder 200 may include a die 230 including a rectangular, for example, rectangular extrusion hole 235 for extruding the extrudate 250 into the plate-like extruding material 260. The extrusion hole 235 includes a tapered portion 234 whose width varies along the extrusion direction of the extruded material 250, and the tapered portion 234 is asymmetrical with respect to the extrusion direction, for example, the plate direction of the plate shape. It may have a shape. The asymmetric rolling mill 100 may include a first roll 101 and a second roll 102. The first roll 101 is in contact with the first face 104a of the rolled material 104, and the second roll 102 has a larger diameter than the first roll and is the opposite side of the first face 104a. It may be in contact with the second surface 104b.

Using such an asymmetric processing apparatus, the extruded material 250 may be extruded using the asymmetric extruder 200 to produce an extruded material 260, and the extruded material 260 may be used as the rolled material 104. This extruding step pushes the extrudate 250 through the die 230 having an extrusion hole 235 having an asymmetrical shape with respect to the extrusion direction of the extrudate 250, for example, the plate surface direction, thereby extruding the extrudate 250. It can be carried out while inducing shear deformation in the thickness direction of the inside.

Next, the rolled material 120 can be formed by rolling the rolled material 104 using the asymmetric rolling mill 100. This asymmetrical rolling step can be carried out continuously following the asymmetrical extrusion step using the extruded material 260 as the rolled material 104. For example, the rolled material 104 may be pushed between the first roll 101 and the second roll 102 having different diameters to induce shear deformation force on the rolled material 104.

On the other hand, unlike shown in Figure 1, the asymmetrical extrusion step and the asymmetrical rolling step may not be performed continuously, it may be performed intermittently. In this case, the extruded material 260 can be cut into a predetermined size and used as the rolled material 104. Furthermore, the rolling mill 100 and the extruder 200 may be provided as separate systems from each other. In this case, after extruding in the extruder 200 to produce an extruded material 260, it is cut to move to a predetermined size to move and then rolled in the rolling mill 100 can be produced a rolled material (120).

According to the above-described embodiment, the workpiece, for example, the extruded material 250 is asymmetrically processed in the asymmetric extruder 200 primarily to make the texture-controlled extruded material 260, which is again asymmetrical rolling mill 100 By asymmetrical processing in the second texture-controlled rolling material 120 can be produced as a final processing material. According to this, since the texture of the final workpiece is controlled over the secondary, workability can be greatly improved. An effect of the texture control through the asymmetrical extruder 200 and the asymmetrical rolling mill 100 on the processability improvement will be described later with reference to FIGS. 3 to 27.

2 is a schematic cross-sectional view of an asymmetric processing apparatus according to another embodiment of the present invention. The asymmetrical machining apparatus according to this embodiment is a modification of some order in the asymmetrical machining apparatus of FIG. 1, and thus duplicated description is omitted in both embodiments.

Referring to FIG. 2, the asymmetric extruder 200 may be disposed after the asymmetrical rolling mill 100. The cutter 300 may be disposed between the rolling mill 100 and the extruder 200. According to this, after the rolled material 120 produced by the rolling process is cut to a suitable size by the cutter 300, the extruding material (exposed to the container 210 coupled to the rear end of the die 230 of the extruder 200) 250). Subsequently, the extrudate 250 is compressed by the stem 220 sealing the inner hole 215 of the container 210 to extrude the material 260 through the die 230 having the extrusion hole 235 having an asymmetric shape. It can be prepared as.

On the other hand, the rolling mill 100 and the extruder 200 may be provided as a separate system from each other. In this case, the extruded material 260 may be manufactured by moving the extruded material 120 rolled by the rolling mill 100 and extruding the extruder 200.

Hereinafter, the processing apparatus used in the embodiments of the present invention will be described by dividing into a rolling mill and an extruder, and a rolling method and an extrusion method using the same will be described in more detail.

3 (a) and 3 (b) is shown a rolling mill of the asymmetric processing apparatus according to an embodiment of the present invention. Specifically, Figure 3 (a) is a front view of the rolling mill 100 of the processing apparatus according to an embodiment of the present invention, Figure 3 (b) is a rolling

roll

101, 102 of the rolling device of Figure 3 (a) And only a part of the material to be rolled 104 is a perspective view.

As shown in Figure 3 (a) and 3 (b), in the rolling apparatus 100 according to an embodiment of the present invention asymmetrical rolling of different diameters of the first roll 101 and the second roll 102 A device, specifically, having a larger diameter than the first roll 101, the first roll 101 in contact with the first face 104a of the rolled material 104, and having the first surface 104a of the rolled material 104. The second roll 102 in contact with the second surface 104b, which is the opposite side of the surface, and the rotational angular velocity of the first roll 101 and the second roll 102 can be adjusted differently from each other. 101 and a power providing unit 105 for supplying power to the second roll (102).

3 (a) and 3 (b), the first and

second rolls

101 and 102, which are working rolls for rolling, are set as upper and lower rolls, respectively. It may be set in a different form. In addition, for convenience of description, the surface which contacts the 1st roll 101 which is an upper roll among the surfaces of the to-be-rolled material 104 rolled by the rolling apparatus 100 of FIG. 1 is the 1st surface 104a and the 2nd roll which is a lower roll. The surface which contacts 102 is defined as the 2nd surface 104b. Accordingly, when rolling the rolled material 104 of FIG. 1 upside down, the first roll 101 comes into contact with the second surface 104b of the rolled material 104, and the second roll 102 is rolled material 104. It is in contact with the first surface (104a) of.

The first and second rolls 101 are formed between the frames 111 that are formed to be spaced apart in parallel on the pedestal 110 and fixed by fastening members 112 such as screws. As shown in FIG. 3 (a), the power supply 105 includes a first motor 106 and a second motor 107 which drive the first roll 101 and the second roll 102, respectively. It may include a motor control unit 108 that can control the rotational angular velocity of the first motor 106 and the second motor 107. The first motor 106 and the second motor 107 transmit rotational power to the first roll 101 and the second roll 102 through the connecting member 109.

The motor controller 108 may control the rotational angular velocities of the first roll 101 and the second roll 102 connected thereto by controlling the rotational angular velocities of the first motor 106 and the second motor 107. The control can control the rotational linear velocity, which is defined as the diameter of the roll multiplied by the rotational angular velocity. Through the control of the rotational linear speed, the shear deformation force applied by the first roll 101 to the first surface 104a of the rolled material 104 and the second roll 102 of the rolled material 104 The shear deformation force applied to 104b) can be controlled to be different from each other.

As an example, the motor control unit 108 maintains the rotational linear velocity of the first roll 101 and the second roll 102 and is the rolled material disposed between the first roll 101 and the second roll 102. 104) can be controlled to roll. That is, by controlling the ratio of the angular velocities of the first roll 101 and the second roll 102 to be equal to the ratio of the reciprocal of the diameters of the first roll 101 and the second roll 102, the first roll 101 and the second roll 102 are controlled. The linear velocity of the roll 102 can be kept the same. The term "same" here means not only the same thing, but also the identity within the process margin due to the error inevitably inherent in the characteristics of the machine, even though the operator controls the signal of the controller with the intention of equalizing the angular velocity of both rolls. It should be seen as the identity of the actual meaning it includes. The same " same " of the rotational linear velocities of the first roll 101 and the second roll 102 is also applied in the following sense.

On the other hand, as another embodiment according to the present invention, as shown in Figure 4 (a) and 4 (b), has a larger diameter than the first roll 101 and the opposite side of the second roll 102 It may further include a third roll 103 coupled to the first roll 101 to be disposed to support the first roll 101. In this case, the first roll 101 and the second roll 102 may be a working roll for directly contacting the surface of the rolled material 104 to apply shear deformation force, and the third roll 103 may be The first roll 101 may be a backup roll to balance the external force applied from the second roll 102 having a larger diameter during the rolling process.

The power supply unit 105 may include a first motor 106 driving the first roll 101 or the third roll 103, a second motor 107 driving the second roll 102, and the first motor. It may include a motor control unit 108 that can control the rotational angular speed of the motor 106 and the second motor 107.

As an example, the first motor 106 is connected to the third roller 103 and transmits a driving force as shown in FIG. 4 (a), and the first motor 106 is coupled to be in contact with the rotation of the third roller 103. The roll 101 is rotated together by friction. Although not shown, the first motor 106 is connected to the first roll 101 to rotate the first roll 101, it is also possible to rotate the third roll 103 by friction in the same principle as above.

Meanwhile, in another embodiment according to the present invention, the power provided from the power supply may be transmitted to the work roll through the gear. As an example, as shown in FIG. 5, in the rolling mill composed of the first roll 101 to the third roll 103, the first gear 114 connected to the first roll 101 or the third roll 103 and And a second gear 115 connected to the second roll 102 and coupled with the first gear 114 with a different gear ratio, wherein the power supply 105 includes the first gear 114 or the second gear. It may include a motor 113 for transmitting a driving force to the gear 115.

In FIG. 5, the power of the motor 113 is configured to be transmitted to the second gear 115 through the drive gear 116. However, the rolling mill of the present embodiment is not limited thereto, and the motor 113 is provided without the drive gear 116. It also includes a power directly connected to the first gear 114 or the second gear 115.

In addition, although FIG. 5 shows a rolling machine with a third roll 103 as a reinforcing roll, the same as described above even when only the first roll 101 and the second roll 102 are provided without the third roll 103. The first gear 114 can be connected to the first roll 101 and the second gear 115 can be connected to the second roll 102 in a manner.

Meanwhile, the above-described first gear 114 or second gear 115 may be in the form of a variable gear that can variably change one or more gear ratios. In order to control the gear ratio, the first gear 114 or the second gear 115 may be used. It may further include a gear control unit 117 connected to the gear 115.

In the case of the rolling mill of the processing apparatus according to this embodiment, by adjusting the gear ratio of the first gear 114 and the second gear 115 in consideration of the diameter of the first roll 101 and the second roll 102. The rotational linear speed of both rolls can be controlled. As an example, the power generated from the motor 113 may be transmitted so that the first roll 101 and the second roll 102 have the same rotational linear velocity according to the gear ratio set as described above. In addition, when the first gear 114 and the second gear 115 is composed of a variable gear, the gear ratio is adjusted according to the diameter of the first roll 101 or the second roll 102 mounted by the gear control unit 117. By varying the control, it is possible to equally control the rotational linear speeds of the first roll 101 and the second roll 102.

Meanwhile, although FIGS. 3 to 5 illustrate a work roll in which a first roll 101 and a second roll 102 having a difference in diameter form a pair, the present invention is not limited thereto. It also includes the case where a plurality of rolls are formed in close proximity. Therefore, the rolling process of the processing method described as all embodiments of the present invention may include a method of rolling the rolled material using at least one working roll of a pair of rolling rolls having different diameters from each other.

The rolled material to be rolled by the asymmetrical rolling device may include magnesium or magnesium alloy having a hexagonal close-packed (HCP) structure. Recently magnesium being studied as a next-generation light-weight member has a very good nasal help non-elastic coefficient lighter than aluminum a density of 1.74g / cm ³ as the density of 7.90g / cm ³ or of iron, 2.7g / cm ^3. In addition, it has excellent absorption ability against vibration, shock, electromagnetic waves, etc., and has excellent electric and thermal conductivity, so it is applied to the electronics industry such as mobile phones and laptops as well as lightweight materials such as automobiles and aircrafts.

However, magnesium having such a densely packed hexagonal crystal structure does not develop a slip system for molding, resulting in poor moldability at room temperature. That is, as shown in FIG. 6, the deformation mechanism of magnesium is mainly based on a base plane slip system of {0001} <1120> and a {1010} <1120> prismatic slip system. ), {1011} <1120> pyramidal slip systems and the like are known to act. However, since the critical resolved shear stress values for changing mechanisms other than the base slip system at room temperature are very large compared to the critical resolved shear stress of the base slip system, the placement of the base slip system in the specimen is dependent on the room temperature formability. It will have a significant impact.

As shown in FIG. 7A, the base slip system is disposed parallel to the rolled surface of the rolled material 104 (that is, perpendicular to the ND of FIG. 7) or the base slip system in the horizontal axis direction TD as shown in FIG. 7B. When the base surface slip system is arranged perpendicular to the rolling direction RD as shown in FIG. 7C or vertically, the moldability at room temperature becomes poor. This is because the peripheral surface direction (ie, ND, RD, and TD in FIG. 7) and the base surface slip system are perpendicular or horizontal to each other when the rolled magnesium is formed, making it difficult to operate the base surface slip system by external stress.

On the other hand, when the base surface slip system is inclined at a predetermined angle with respect to the peripheral direction to facilitate deformation of the material as shown in FIG. 7D, excellent room temperature formability is exhibited.

The arrangement direction and distribution of the base slip system in such a material can be confirmed by the (0001) pole figure of FIG. 8, in which the arrangements A, B, C, The pole arrangement on the (0001) pole figure according to D is shown.

When rolling is performed using a rolling mill of the asymmetric processing apparatus according to one embodiment of the present invention shown in Figures 3 to 5, such an arrangement of crystals of magnesium or magnesium alloy may be arranged to favor formability. Specifically, in the rolling process of the asymmetric processing method according to an embodiment of the present invention, the rolled material 104 including the first surface 104a and the second surface 104b is formed of the first roll 101 and the second roll ( The first surface 104a of the material to be rolled 104 by the first roll 101 and disposed between the plurality of rolls 102 and the rotational angular velocities of the first roll 101 and the second roll 102 are adjusted differently from each other. Any one of the second surface 104b, for example, any other of the first surface 104a and the second surface 104b by the shearing force applied to the first surface 104a and the second roll 102. For example, the rolled material 104 may be rolled by controlling the shear deformation forces applied to the second surface 104b to be different from each other.

At this time, as an example, the to-be-rolled material 104 can be rolled, keeping the rotational linear velocity of the 1st roll 101 and the 2nd roll 102 the same. In addition, the material to be rolled 104 may include an alloy name AZ31 as a magnesium alloy, hereinafter, AZ31 alloy is illustrated as a material to be rolled.

Meanwhile, the rolling process of the asymmetrical processing method according to another embodiment of the present invention includes a method of rolling the same rolled material over a plurality of times. Such a plurality of times rolling method may be carried out to prevent a problem appearing when the sudden reduction amount is applied by sequentially applying the reduction amount adjusted to an appropriate level to the rolled material.

In this case, the plurality of times means that the rolled material rolled by the work roll is put into the same work roll again, or the rolled material passes through the work rolls provided in plurality, so that the total number of rolls of the rolled material becomes two or more times. The rolled material to be rolled into the work roll includes both continuous and intermittent cases.

In addition, the plurality of times is not only re-inserted after the rolled material is physically separated from the work roll of the rolling apparatus, but also reworked as the direction of rotation of the work roll is reversed while the rolled material is still disposed between the work rolls. It also includes the case where it is thrown in between rolls. In this case, each rolling operation constituting a plurality of times may be referred to as a "pass".

FIG. 9 shows a pole figure when rolling the AZ31 alloy five times while controlling the first roll 101 and the second roll 102 to have the same rotational linear velocity using the rolling mill illustrated in FIG. 4. It is. At this time, the reduction ratio of the AZ31 alloy was 75%, and the rolling temperature was 300 ℃. Rolling five times is applied in the same rolling direction, the first surface 104a and the second surface 104b of the AZ31 to be rolled in contact with the first roll 101 and the second roll 102 to apply the shear strain force, respectively. 9 is a pole figure of the first surface 104a subjected to the shear deformation force by the first roll 101, and the upper view is the shear deformation force by the second roll 102. It is the (0001) pole figure of the received second surface 104b.

As shown in Figure 9, in the rolling process of the asymmetric processing method according to an embodiment of the present invention the crystallographic direction of the base surface, that is, the (0001) plane of the (0001) plane on the (0001) pole figure is clearly off the center It can be seen that. Specifically, the rotational angle (ie, the off-center angle) of the base pole at the first surface 104a subjected to the shear deformation by the first roll 101 was about 15 degrees, and the shear deformation by the second roll 102. It was about 6 degrees in the 2nd surface 104b which received.

As a comparative example, FIGS. 10-12 show the pole figure after rolling magnesium alloy AZ31 using the conventional rolling apparatus which has a working roll with the same diameter.

The pole figure of FIG. 10 has a reduction ratio of 75%, and the first and second surfaces of the AZ31 alloy, which is the rolled material, are in contact with the first roll and the second roll, respectively, while maintaining the rolling temperature at 300 ° C. (0001) The pole figure after rolling over a plurality of times after setting to apply is the result. Specifically, FIG. 10 (a) shows the rolling amount per rolling being 10% and rolled 12 times, and FIG. 10 (b) shows the rolling reduction 6 times with a rolling reduction of 20% per roll, and then FIG. 10 (c). ) Shows the pole figure after rolling 4 times with 30% reduction of rolling per roll. As shown in Figure 10 (a) to Figure 10 (c), it can be seen that in all conditions the poles have a maximum pole strength of 10 or more and all are centered.

11 (a) to 11 (c), which are other comparative examples, were obtained from the AZ31 alloy which was rolled while maintaining the rolling temperature at 200 ° C., and the rolling reductions were 50%, 30%, and 15%, respectively. As shown in Figure 11 (a) to Figure 11 (c), it can be seen that the poles of the base surface also have a maximum pole strength of 12 or more and are all gathered at the center.

From these results, when the rolling is performed by a conventional rolling apparatus having the same size of the first roll and the second roll, the poles of the base surface are collected at the center even if the rolling reduction or the rolling temperature is changed. It can be seen that the aggregate structure of the AZ31 alloy rolled by the present invention is arranged in a direction in which formability is remarkably improved compared to the AZ31 alloy rolled using a conventional rolling roll having the same diameter.

On the other hand, Figure 12 (a) to Figure 12 (c) is a conventional roll roll while maintaining the rotational linear speed of any one of the work roll having the same diameter larger than the rotational linear speed of any other roll The (0001) pole figure of the AZ31 alloy rolled by the two-speed rolling method of is shown. At this time, the ratio of the rotational linear velocity of both rolls having different rotational linear speeds was maintained at 3: 1 and the rolling temperature was 200 ° C., and the reduction amounts were 70%, 30%, respectively in FIGS. 15%. 12 (a) to 12 (c) are bottom views of the surface subjected to shear deformation by a rapidly rotating roll, and the top view of the surface subjected to shear deformation by a slowly rotating roll ( 0001) pole figure.

Even when such two-speed rolling is performed, the orientations of the crystals are gathered toward the center, as shown in FIG. 9, regardless of the rolling reduction and the rotational linear velocity difference between the two rolls. It can be seen that the result of moving from the center does not appear.

From this, the AZ31 alloy rolled by the rolling process of the asymmetric processing method according to an embodiment of the present invention is superior in the crystallographic direction of the base surface compared to the AZ31 alloy rolled using a rolling roll having the same diameter as in Comparative Example It can be seen that they are arranged in a direction that can have sex.

In addition, in the case of two-speed rolling using a work roll having the same diameter, the shear deformation force is not applied to the rolled material from the actual rolling roll due to the sliding phenomenon of the rolled material during rolling due to the difference in the rotational linear speed of both rolls. There is a problem that the rolled material exiting the rolling roll is bent or the surface is rough.

In contrast, in the rolling process of the asymmetric processing method according to an embodiment of the present invention, the application of the asymmetric shear deformation force due to the difference in diameter of the two rolls is performed during the process in which both rolls have the same rotational linear velocity. Sliding the rolled material did not occur even in asymmetrical rolling, and there was no problem of warping or surface roughening of the rolled material as in two-speed rolling.

On the other hand, according to the rolling process of the asymmetric processing method according to another embodiment of the present invention, the rotational angular velocity of the first roll 101 and the second roll 102 is the difference of the rotational linear speed defined by Equation 1 below Can be controlled to be 10% or less.

Equation 1:

: Rotational linear velocity of the first roll

: Rotational linear velocity of the second roll

At this time, when the difference in the rotational linear velocity defined by the above equation of the first roll 101 and the second roll 102 having different diameters is greater than 10%, the rolled material exiting the rolling rolls may be unbalanced. Problems such as bending may occur.

On the other hand, as an embodiment of the rolling process of the asymmetric processing method consisting of a plurality of times, the number of times to change the surface subjected to the shear deformation force from the first roll 101 and the second roll 102 of the material to be rolled (104) It includes a method of rolling the rolled material two or more times, including at least once.

For example, as shown in FIG. 13, the rolling direction is the same, and in the first pass of rolling, the first surface 104a of the rolled material 104 is formed on the first roll 101 and the second roll 102. ) And the rolled material 104 is placed and rolled so that the second surface 104b is in contact with each other, and then the first surface 104a of the same rolled material 104 is in contact with the second roll 102 and is The second pass of rolling can be performed by turning over the to-be-rolled material 104 so that the two surfaces 104b may contact the first roll 103. In this case, a plurality of passes of two or more passes may be performed in a batch type in the same rolling roll, or may be performed in a plurality of different rolling rolls in charge of each pass.

In this case, due to the difference in diameter between the first roll 101 and the second roll 102, the shear strain applied asymmetrically is alternately applied to the first surface 104a and the second surface 104b and rolled accordingly. It is possible to obtain the effect that the shear strain applied to each side of the first pass and the second pass of the averaged to a certain level. The number of rolling may be performed two or more times according to the desired rolling reduction, and if the first and second surfaces of the rolled material are rolled alternately up and down with each other, the number or alternating cycle is limited. There is no

FIG. 14 shows the pole figure in the case where rolling of the AZ31 alloy, which is a rolled material, is carried out once in a rolling temperature of 300 ° C. in alternating rolling surfaces up and down to perform a total of five passes of rolling (75% reduction ratio). It is. It can be seen that the rotation angle of the base surface is about 17 degrees, which is significantly higher than the pole figure shown in FIGS. 10 to 12.

Meanwhile, the rolling process of the asymmetrical processing method according to another embodiment of the present invention includes all methods of rolling over a plurality of times while varying the rolling direction. For example, as shown in FIG. 15, in the first pass of rolling, rolling of the rolled material 104 such that the A direction of the rolled material 104 is first introduced between the first roll 101 and the second roll 102. After setting the direction, the first surface 104a and the second surface 104b of the same rolled material 104 are continuously maintained in the same manner as in the first pass, and then only 180 degrees of the direction to be introduced into both rolling rolls is changed. It is a method of setting so that the B direction of the extending | stretching material 104 may input first.

FIG. 16 shows the pole figure in the case of performing rolling (pass rate of reduction 75%) in a total of 5 passes by rolling the AZ31 alloy, which is a rolled material, at a rolling temperature of 300 ° C. in a cycle of 180 degrees in a single cycle. . 16 is a pole figure of a first surface 104a subjected to shear deformation force by the first roll 101, and an upper view is a second surface subjected to shear deformation force by the second roll 102 This is the (0001) pole figure of (104b). As shown in FIG. 16, the rotation angle was about 5 degrees at the first surface 104a sheared by the first roll 101, and the second surface sheared by the second roll 102. It was about 17 degrees at 104b. From this it can be seen that the rotation angle is significantly higher than the poles shown in Figures 10 to 13.

As another example of the method of rolling a plurality of times with different rolling directions, as shown in FIG. 15, the rolled material is not only re-injected after being physically separated from the work roll of the rolling apparatus, but also the rolled material is worked. It also includes a case in which the work rolls are placed again between the work rolls as the rotation direction of the work rolls is reversed while still being disposed between the rolls.

The rolling mill and the rolling process using the asymmetric processing apparatus described above can be applied to any material that controls the texture of the rolled material in addition to the magnesium or the magnesium alloy from above. For example, a metal material with a dense packed hexagonal crystal structure containing titanium (Ti) or a titanium alloy is used as a rolled material, or the crystallographic direction of a metal material or a rolled material including aluminum or an aluminum alloy affects the magnetic properties. Fe-Si alloys can also be included in the rolled material.

Hereinafter, with reference to the accompanying drawings an extruder of a processing apparatus according to an aspect of the present invention will be described in more detail.

17 is a schematic cross-sectional view showing an extruder of an asymmetric processing apparatus according to an embodiment of the present invention. FIG. 18 is a partially cut away perspective view showing a die of the extruder of FIG. 17. 19 is a plan view of the dice of FIG. 18.

Referring to FIG. 17, a container 210 for charging the extruded material 250 may be provided. For example, the extruded material 250 may be charged into the inner hole 215 in the container 210 in the form of a billet. As another example, the extrudate 250 may be loaded into the inner hole 215 in the container 210 in the form of powder or green compact. The container 210 may have an inner hole 215 and an outer shape having various shapes to accommodate the extruded material 250. Therefore, the shape of the extrudate 250 and the container 210 may be variously modified, and does not limit the scope of this embodiment.

The stem 220 may be disposed in the container 210 to compress the extruded material 250 into the container 210. For example, for effective compression of the extrudate 250, the shape of the stem 220 can be tailored to the shape of the inner hole 215 of the container 210. As another example, the appearance of the stem 220 may not match the shape of the inner hole 215, in which case a portion of the extrudate 150 may remain uncompressed in the container 210. Stem 220 may be referred to as a ram or compressor, and the scope of this embodiment is not limited by its terminology and shape.

The die 230 may be coupled to the front end of the container 210 opposite the stem 220. For example, the stem 220, the container 210, and the dice 230 may be coupled in a row, for example, arranged in the X-axis direction of FIG. 17. This X-axis direction may be the extrusion direction of the extrudate 250. In a modified example of this embodiment, the stem 220, the container 210, and the dice 230 may not be arranged in a line, in which case the extrusion direction may be primarily determined based on the dice 230.

The die 230 may have an extrusion hole 235 that defines the extrusion shape of the extrudate 150. The extruded material 150 may be converted into a plate-shaped extruded material 160 while passing through the extrusion hole 235 in the die 230. For example, in FIG. 17, the XY plane is the plate surface direction of the extruded material 160, the Z axis direction is the thickness direction of the extruded material 160, the X axis direction is the longitudinal direction of the extruded material 160, and the Y axis direction is It may be the width direction of the extruded material 160.

The extrusion hole 235 may include a tapered portion 234 having a variable width and a fixed portion 232 having a constant width. The extrudate 250 compressed by the stem 220 may be substantially varied in width and shape as it passes through the tapered portion 234 and then extruded into the shape of the extrudate 260 while passing through the fixing portion 232. have. The tapered portion 234 of the extrusion hole 235 may have an asymmetrical shape with respect to the extrusion direction (X-axis direction) in order to control the texture of the extrusion material 260 as described below.

18 and 19, in order to extrude the plate shape, the extrusion hole 235 may have a rectangular cross-sectional shape with respect to the YZ plane. The die 230 defines an extrusion hole 235 and has a first inner surface 242 and a second inner surface 244 opposite to the first and second surfaces of the extrudate 250 and the left and right sides of the extrudate ( And a third inner surface 246 and a fourth inner surface 248 opposite to each other. The first inner surface 242 and the second inner surfaces 244 are spaced apart along the thickness direction (Z-axis direction) of the extruded material 250 or the extruded material 260, and the third inner surface 246 and the fourth inner surface ( 248 may be spaced apart from each other in the width direction (Y-axis direction) of the extruded material 250 or the extruded material 260.

The first inner surface 242 and the second inner surface 244 may define a plate surface of the extruded material 260. The first inner surface 242 and the second inner surface 244 may be asymmetrically disposed with respect to the plate direction (XY plane) of the extruded material 260 to effectively induce shear deformation in the extruded material 260. For example, the first inner surface 242 and the second inner surface 244 may extend at different inclinations. For example, the first inner surface 242 may have a predetermined slope with respect to the extrusion direction (X-axis direction), and the second inner surface 244 may be parallel to the extrusion direction (X-axis direction).

Accordingly, the extruded material 250 may be subjected to a large shear deformation by varying its deformation angle between the first inner surface 242 and the second inner surface 244. In this embodiment, the shear deformation between the first inner surface 142 and the second inner surface 244 can be rather straightforward because the second inner surface 244 is parallel to the extrusion direction, and thus can be easily controlled. . Such shear deformation may greatly affect the texture deformation of the plate material of the extruded material 260. The change in the texture may have a great influence on the moldability of the extruded material 260 as described later.

The third inner surface 246 and the fourth inner surface 248 may define sides of the extruded material 260. When the extruded material 260 has a plate shape, the third inner surface 246 and the fourth inner surface 248 may not significantly affect the texture of the extruded material 260. Accordingly, the third inner surface 246 and the fourth inner surface 248 may be symmetrically disposed, for example, parallel to the thickness direction (Z-axis direction) of the extruded material 260. In a modified example of this embodiment, the third inner surface 246 and the fourth inner surface 248 may be arranged asymmetrically.

Hereinafter will be described an extrusion process of the asymmetric processing method according to an embodiment of the present invention. Extrusion process of the asymmetric processing method according to this embodiment can be described with reference to the extruder of Figs.

17 to 19, the extruding material 250 may be charged into the container 210. Subsequently, the extrudate 250 in the container 210 may be compressed using the stem 220. Subsequently, the extruded material 250 may be pushed out through the die 230 to form an extruded material 260 having a plate shape. As described above, since the die 230 has extrusion holes 235 having an asymmetrical shape with respect to the extrusion direction, the extruded material 250 can be extruded while inducing shear deformation in the extruded material 250. Extrusion process of this asymmetric processing method can be understood in more detail with reference to the description of the extruder of FIGS. 17 to 19 above.

As described above, by inducing shear deformation in the extrudate 250, the texture of the extrudate 260 can be controlled. Accordingly, the texture of the extruded material 260 may be different from that of the extruded material 250. Therefore, in the case of the extruded material 250 having poor moldability under ordinary extrusion conditions, the moldability of the extruded material 260 may be improved by extruding the aggregated structure.

According to the extrusion process of the asymmetric processing method according to another embodiment of the present invention, the charging step of the extrusion material 250 and the compression step of the extrusion material 250 may be variously modified or omitted. For example, the extruded material 250 may be charged directly into the die 230 and compressed in the die 230. As another example, the charging step, the compression step and the extrusion step of the extrudate 250 may be referred to as a series of extrusion steps without being distinguished from each other.

The extrusion process of the asymmetrical processing method according to the above embodiments has been described with reference to the extruder of the asymmetrical processing apparatus of FIGS. 17 to 19, but the range is not limited to this apparatus structure.

On the other hand, the extruded material 260 manufactured according to the extrusion process of the above-described asymmetric processing method may be repeatedly subjected to the above asymmetric extrusion process or more rough rolling process in order to make the thickness thereof thinner.

20 is a partially cut perspective view showing a die 230a included in an extruder of an asymmetric processing apparatus according to another embodiment of the present invention. FIG. 21 is a cross-sectional view of the dice 230a of FIG. 20. The die 230a according to this embodiment corresponds to a modification of some configurations in the die 230 of FIGS. 17 to 19, and thus, redundant descriptions of the two embodiments are omitted.

20 and 21, the extrusion hole 235 may still have an asymmetrical shape with respect to the extrusion direction (X-axis direction). In this embodiment, the first inner surface 242 and the second inner surface 244a defining the tapered portion 234a may have different angles of inclination relative to the extrusion direction (X-axis direction). The first inner surface 244a is not parallel to the extrusion direction and may extend at an angle different from that of the first inner surface 242. The inclination of the first inner surface 242 and the second inner surface 244a is exemplarily illustrated, and may be variously modified within a range in which the first inner surface 242 and the second inner surface 244a have different inclinations. .

According to this, the tapered portion 234a of the extrusion hole 235 may still have an asymmetrical shape with respect to the extrusion direction. In particular, the tapered portion 234a of the extrusion hole 235 may have an asymmetrical shape with respect to the plate direction (XY plane) of the extrusion material (260 of FIG. 17).

Accordingly, the material to be extruded (250 of FIG. 17) may still undergo shear deformation because its deformation angle is different between the first inner surface 242 and the second inner surface 244a. However, since the first inner surface 242 and the second inner surface 244a are both inclined with respect to the extrusion direction, the shear deformation may be somewhat complicated. Such shear deformation may affect the texture deformation of the extruded material (260 of FIG. 17).

The extrusion process using the die 230a of FIGS. 20 and 21 may be understood from the above description, and further may be understood with reference to the description of the extrusion method using the die 230 of FIGS. 18 and 19. .

The extruded material (250 of FIG. 17) to which the aforementioned asymmetric extruder and asymmetrical extrusion process are applied may include various materials. For example, the extrudate 250 may include various metals having a texture or a metal alloy thereof. Such metals or metal alloys may have a variety of crystal structures, such as hexagonal closed-packed (HCP), face centered cubic (FCC), body centered cubic (BCC) structure, etc. Can have Since the crystal structure is as described above, detailed description is omitted to avoid duplication.

22 is a (0001) pole figure in the + Z axis direction of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention. Figure 23 is a (0001) pole figure in the -Z axis direction of the AZ31 sheet extruded by the extrusion process of the asymmetric processing method according to an embodiment of the present invention. 24 is a (0001) pole figure of the AZ31 sheet according to the comparative example.

22 and 23, it can be seen that the AZ31 plate asymmetrically extruded according to the embodiment of the present invention has a crystallographic direction of the base surface, that is, the (0001) plane, clearly deviated from the center on the (0001) pole figure. The arrangement on the (0001) pole figure of the asymmetrically extruded AZ31 sheet is similar to the fourth specimen D of FIGS. 7 and 8. Thus, asymmetrically extruded AZ31 sheet material is arranged so that its base surface slip system maintains a constant angle with the peripheral direction, showing excellent formability.

On the other hand, as shown in Figure 24, it can be seen that the AZ31 plate according to the comparative example of the symmetrically rolled or symmetrically extruded, the crystal direction of the base surface is disposed in the center on the (0001) pole figure. This arrangement is similar to the first specimen A of FIGS. 7 and 8, so that the AZ31 sheet according to the comparative example is difficult to expect excellent formability.

25 is a true stress-strain graph of the AZ31 sheet extruded by the extrusion process of the asymmetric extrusion-rolling composite method according to an embodiment of the present invention. 26 is a true stress-strain graph of the AZ31 sheet according to the comparative example.

Referring to FIG. 25, in the case of the asymmetrically extruded AZ31 sheet according to the embodiment of the present invention, it can be seen that a high elongation of 35% or more. On the other hand, as shown in Figure 26, the AZ31 plate according to the comparative example it can be seen that the low elongation of 15 ~ 20%. Therefore, it can be seen that the elongation of the AZ31 sheet can be greatly improved by using the asymmetric extrusion method. This improvement in elongation can lead to improved formability of the AZ31 sheet.

Referring to FIG. 27, it can be seen that the asymmetrically extruded AZ31 sheet has not high anisotropy according to the tensile angle and has a high r-value of steel level.

As described above, the AZ31 plate asymmetrically extruded according to the embodiments of the present invention has a significantly different texture than the AZ31 plate according to the comparative example, it can be seen that exhibits high elongation and excellent formability.

The description of the metal or metal alloy having the above-described HCP structure may be applied on a similar principle to metals or metal alloys having other structures, such as BCC structures, FCC structures, and the like.

The above-mentioned embodiments are illustrative rather than limiting on the present invention, and those skilled in the art can design many other embodiments without departing from the scope of the present invention as defined by the appended claims. It is apparent that such techniques of the present invention can be easily modified by those skilled in the art, and these modified embodiments will be included in the technical spirit described in the claims of the present invention.

Claims

Manufacturing an extruded material by extruding the extruded material by pushing the extruded material through a die having an extrusion hole having an asymmetrical shape with respect to the plate surface direction of the extruded material to induce shear deformation in the thickness direction of the extruded material; ; And

Using the extruded material as a rolled material, pushing the rolled material between the first and second rolls having different diameters and rolling the rolled material while inducing shear deformation force on the rolled material to produce a rolled material; Asymmetric processing method which includes.
The method of claim 1, wherein in the step of manufacturing the extruded material, the extrusion hole of the die comprises a tapered portion whose width is varied along the extrusion direction of the extruding material, the tapered portion is directed to the plate surface direction of the extruded material Asymmetric processing method, arranged to have an asymmetrical shape as a reference.
The method of claim 1, wherein the manufacturing of the rolled material

The rotational angular velocities of the first roll and the second roll are adjusted differently from each other, so that the shear deformation force applied to any one of the first and second surfaces of the rolled material by the first roll and the second roll. Rolling the rolled material by controlling the shear strain applied to any one of the first and second surfaces to be different from each other, asymmetric processing method.
The method of claim 3, wherein the manufacturing of the rolled material is performed by rolling the rolled material while maintaining the rotational linear velocities of the first and second rolls.
4. The method of claim 3, wherein the manufacturing of the rolled material comprises a difference in rotational linear velocity defined by Equation 1 regarding a difference in rotational linear velocity of the first roll and the second roll. 10.

Equation 1:

: Rotational linear velocity of the first roll

: Rotational linear velocity of the second roll
The method of claim 3, wherein the manufacturing of the rolled material comprises: setting the first roll to apply the shear strain force to the first face and the second roll to apply the shear strain force to the second face. Rolling the rolled material more than once, the asymmetric processing method.
The method of claim 1, wherein the manufacturing of the rolled material includes rolling the rolled material at least once by changing a surface to which shear strain is applied from the first and second rolls of the rolled material. Asymmetric processing method.
The method of claim 1, wherein the manufacturing of the rolled material comprises rolling the rolled material two or more times by setting the same rolling direction of the rolled material.
The method of claim 1, wherein the manufacturing of the rolled material comprises rolling the rolled material at least once by changing a rolling direction of the rolled material.
The method of claim 1, wherein the manufacturing of the rolled material supports the first roll by joining a third roll having a larger diameter than the first roll to the first roll on the opposite side of the second roll. Asymmetric processing method performed by letting.
And a tapered portion whose width varies along the extrusion direction of the plate-shaped extruded material, wherein the tapered portion has an asymmetrical shape with respect to the plate surface direction of the extruded material and the taper along the thickness direction of the extruded material. Extruded through a die disposed spaced apart from the die and including a first inner surface and a second inner surface facing the first and second surfaces of the extruded material to induce shear deformation therein in the thickness direction of the extruded material. Preparing an extrudate; And

Rolling the rolled material using one or more work rolls having a pair of rolling rolls having different diameters rotating at the same rotational linear speed using the extruded material as a rolled material to produce a rolled material Processing method.
12. The method of claim 11, wherein the manufacturing of the rolling material comprises a reinforcing roll for supporting a rolling roll having a smaller diameter in the work roll on the opposite side of the rolling roll having a relatively larger diameter in the work roll. Asymmetric processing method performed by combining.
The method of claim 11, wherein in the step of manufacturing the extruded material, the first inner surface and the second inner surface of the die is arranged to have different inclinations along the extrusion direction to be asymmetric with respect to the plate surface direction of the plate shape, Asymmetric processing method.
The cross section of the extrusion hole has a rectangular shape, and the die includes a third inner surface and a fourth inner surface spaced apart from the tapered portion along the width direction of the plate shape, and the third inner surface and And a fourth inner surface symmetrically disposed along the extrusion direction.
A workpiece manufactured by using the asymmetrical processing method of any one of claims 1 to 14.
A die including a rectangular extrusion hole for extruding the material to be extruded into a sheet shape, the extrusion hole including a tapered portion whose width varies along an extrusion direction of the extruded material, the tapered portion being the sheet material An asymmetrical extruder having an asymmetrical shape relative to the plate surface direction of the shape; And

A first roll contacting the first surface of the rolled material by using the extruded material extruded from the asymmetric extruder as a rolled material; A second roll having a larger diameter than the first roll and in contact with a second face that is opposite the first face; And a power providing unit for supplying power to the first and second rolls so that the ratio of the rotational angular velocities of the first and second rolls can be adjusted.
The method of claim 16, wherein the power supply unit

A first motor and a second motor driving the first roll and the second roll, respectively; And

A controller capable of controlling rotational angular velocities of the first motor and the second motor;

Asymmetric processing apparatus comprising a.
The method of claim 16, wherein the asymmetrical rolling mill,

A first gear connected to the first roll; And

And a second gear connected to the second roll and coupled to the first gear at a different gear ratio.

The power supply unit; asymmetric processing device including; a motor for providing a driving force to the first or second gear.
17. The apparatus of claim 16, wherein the asymmetrical rolling mill further comprises a third roll having a larger diameter than the first roll and coupled to support the first roll opposite the second roll.
20. The apparatus of claim 19, further comprising: a first gear connected to the first roll or third roll; And a second gear connected to the second roll and coupled with the first gear with a different gear ratio.

The power supply unit; a motor for transmitting a driving force to the first gear or the second gear; including, asymmetric processing device.