Dissimilar metal bonding material

Abstract

To provide a dissimilar metal joining material capable of securing joining characteristics of a joining part.SOLUTION: A dissimilar metal joint material includes a first metal plate and a second metal plate, the first metal plate and the second metal plate being different in type from each other and having a longitudinal direction and a width direction, the first metal plate and the second metal plate being arranged side by side in the width direction and joined to each other, a joint portion of the first metal plate and the second metal plate being a joint portion in which a processed region is present on a side of the first metal plate, and SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] This invention is a dissimilar metal joining method in which two different metal plates are joined side by side. Material It is related to. [Background technology]

[0002] When rolling a dissimilar metal bonded material, which is made by joining two different metal plates side by side, the rolled material may bend longitudinally due to the difference in mechanical properties of the two metals. To prevent this bending, jigs are fixed to both ends of the dissimilar metal bonded material and the material is rolled while applying tensile force from both ends. However, this method requires additional jigs, tensioning devices, and work to fix the jigs, and there is also a limit to the length of the dissimilar metal bonded material that can be rolled.

[0003] The applicant is aware of the following Patent Document 1 as a prior art document relating to the rolling of dissimilar metal bonding materials. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 62-50201

[0005] The above-mentioned Patent Document 1 relates to a method for manufacturing an ordinary-bonded alloy plate, and includes the following description. [Bulletin page 1, right column, lines 1 to 7] The present invention has been made to eliminate the above-mentioned conventional drawbacks, and aims to provide a method for manufacturing ordinary-bonded alloy plates that can prevent lateral bending during the rolling process by taking alloy plates of the same type symmetrically arranged about the width center of the ordinary-bonded alloy plate from the same longitudinal position of the same material. DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0006] The above-mentioned Patent Document 1 describes that symmetrically arranged alloy plates of the same kind are taken from the same material at the same longitudinal position, and the dimensional properties of both plates are made uniform.

[0007] However, taking alloy plates of the same kind from the same longitudinal position of the same material and arranging them symmetrically requires strict and complicated process management, and is not easy to realize industrially. Furthermore, the above Patent Document 1 does not mention the relationship between the symmetrically arranged alloy plates of the same kind and the metal plate arranged at the center in the width direction. In other words, the above Patent Document 1 does not mention the relationship between the symmetrically arranged alloy plates of the same kind and the metal plate arranged at the center in the width direction simply by aligning the dimensional characteristics of the alloy plates arranged on both sides. ,gold No consideration is given to the relationship between the attitude do not have.

[0008] The present invention has been made to solve the above problems and has the following objectives. The bonding properties of the joint can be ensured. The present invention provides a dissimilar metal bonding material. [Means for solving the problem]

[0009] The dissimilar metal bonding method according to claim 1 The material is In order to achieve the above object, the following configuration has been adopted. A dissimilar metal joining material in which a first metal plate and a second metal plate that are different in type and have a longitudinal direction and a width direction are arranged in the width direction and joined together, The joint between the first metal plate and the second metal plate is a joint in which a processed region by friction stir welding exists on the first metal plate side, The welded portion includes a crushed compound layer of the first metal and the second metal produced by the friction stirring, and a direct welded portion of the first metal and the second metal. [Effects of the Invention]

[0010] The dissimilar metal bonding method according to claim 1 The material is a dissimilar metal joining material in which a first metal plate and a second metal plate, which are different in type and have a longitudinal direction and a width direction, are aligned and joined in the width direction. The joining portion of the first metal plate and the second metal plate is a joining portion in which a processed area by friction stir welding exists on the side of the first metal plate. The joining portion includes a portion in which a compound layer between the first metal and the second metal formed by the friction stir welding is crushed, and a portion in which the first metal and the second metal are directly joined. In this way, the joining characteristics of the joining portion can be ensured by crushing the compound layer between the first metal and the second metal formed during the friction stir welding and providing a portion in which the first metal and the second metal are directly joined. [Brief explanation of the drawings]

[0011] [Figure 1] 1A and 1B are diagrams illustrating a first embodiment of a dissimilar metal bonding material according to the present invention. [Figure 2] 1A to 1C are diagrams illustrating a method for joining dissimilar metals. [Figure 3] 1A to 1C are diagrams illustrating a first example of a method for manufacturing a dissimilar metal bonding material according to the present invention. [Figure 4] 3A to 3C are diagrams illustrating a second example of a dissimilar metal bonding material and a method for manufacturing the same according to the present invention. [Figure 5] 1 is a photograph showing the appearance of the rolled material of Example 1. [Figure 6] 1 is a photograph showing the appearance of a rolled material of a comparative example. [Figure 7] 1 is a cross-sectional microscope photograph of the vicinity of the joint in Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0012] Next, an embodiment of the present invention will be described.

[0013] First embodiment [Dissimilar metal bonding material] 1A and 1B are diagrams illustrating a first embodiment of a dissimilar metal bonding material of the present invention, where (A) is a plan view and (B) is a front view.

[0014] This dissimilar metal bonding material is made by joining two different metal plates side by side in the width direction (arrow W in the figure) and is intended to be rolled in the longitudinal direction (arrow L1 in the figure). Therefore, the longitudinal direction L1 of each metal plate is parallel to the rolling direction L2 during subsequent rolling.

[0015] The two types of metal plates used are a first metal plate 10 and a second metal plate 20. In this example, the first metal plate 10 and the second metal plate 20 are each rectangular having the longitudinal direction L1 and width direction W described above. The thicknesses of the first metal plate 10 and the second metal plate 20 are substantially equal.

[0016] The first metal plate 10 has a relatively large elongation rate during rolling. That is, the first metal plate 10 has a larger elongation rate in the longitudinal direction L1 during rolling than the second metal plate 20.

[0017] The elongation percentage e during rolling is a value expressed by the following formula. e=(V2-V1) / V1×100 (V1 = inlet speed of the metal plate, V2 = outlet speed of the metal plate)

[0018] The first metal plate 10 has a relatively small expansion rate during rolling. That is, the expansion rate of the first metal plate 10 in the width direction W during rolling is smaller than that of the second metal plate 20.

[0019] The spreading ratio g during rolling is a value expressed by the following formula. g=(b2-b1) / b1 (b1 = width of the metal plate at the entrance, b2 = width of the metal plate at the exit)

[0020] For example, when aluminum is used as the first metal plate 10 and copper is used as the second metal plate 20, the relationship between elongation and spreadability described above is achieved. However, the present invention is not limited to the above combination. In other words, the present invention applies to various combinations of metals as long as the above-described relationship between elongation and spreadability is achieved, and is intended to encompass various combinations of metals. In addition, the metals constituting the first metal plate 10 and the second metal plate 20 are not limited to pure metals, but also include various alloys.

[0021] The dissimilar metal bonding material has a first metal plate 10 on both sides, which has a relatively large elongation rate when rolled, and a second metal plate 20, which has a relatively small elongation rate, placed between them, to form a bonding portion 30 by the bonding. In addition, a first metal plate 10 having a relatively small expansion rate during rolling is placed on both sides, and a second metal plate 20 having a relatively large expansion rate is placed between them, thereby forming a joint 30 by the above-mentioned joining.

[0022] That is, the first metal plate 10 is disposed on both sides in the width direction W, and the second metal plate 20 is disposed therebetween. In this state, the boundaries between the first metal plate 10 and the second metal plate 20, which extend in the longitudinal direction L1 on both sides of the second metal plate 20, are joined to form the joint 30.

[0023] The welded portion 30 is a welded portion 30 that is welded by friction stir welding, in which a rotary tool 40 is inserted into the first metal plate 10.

[0024] [Joining method] 2 is a diagram illustrating a method for joining dissimilar metals, in which a joining method using friction stir welding is explained.

[0025] In this embodiment, the first metal plate 10 and the second metal plate 20 are arranged side by side in the width direction, adjacent to each other with substantially no gap between them. For example, two metal plates are butted together. Although only one first metal plate 10 and one second metal plate 20 are shown in the figure, in this embodiment, as described above, the first metal plate 10 is arranged on both sides in the width direction W, and the second metal plate 20 is arranged therebetween. In this case, two joints 30 are formed, and since the joining method for both is the same, only one of them is shown in FIG. 2 for explanation.

[0026] With the first metal plate 10 and the second metal plate 20 arranged side by side in the width direction, the axially rotating rotary tool 40 is inserted from above onto the first metal member 10. At this time, the rotary tool 40 is inserted so that its outer circumferential edge comes very close to the boundary between the first metal plate 10 and the second metal plate 20. In other words, the outer circumferential edge of the rotary tool 40 almost coincides with the boundary, but does not come into contact with the second metal plate 20. The outer circumferential edge is the outermost rotational trajectory of the rotating rotary tool 40.

[0027] The insertion depth at this time is such that the lower end of the rotary tool 40 is exposed on the lower surface of the first metal plate 10. In other words, the rotary tool 40 is penetrated through the first metal plate 10.

[0028] For example, the rotary tool 40 is inserted into one end in the longitudinal direction L1 and moved in that state along the boundary to the other end. This causes plastic flow in the first metal plate, causing the metal constituting the first metal plate 10 and the metal constituting the second metal plate to adhere to each other at the boundary, thereby joining the first metal plate 10 and the second metal plate 20. In other words, by moving the rotary tool 40 in the longitudinal direction L1, a joint 30 is formed along the longitudinal direction L1.

[0029] In the figure, reference numeral 32 denotes a processing area 32 by the rotary tool 40. The processing area 32 is a band-shaped area along the path of movement of the rotary tool 40. In the processing area 32, plastic flow occurs in the first metal plate 10, and the boundary between the first metal plate 10 and the second metal plate 20 is joined by friction stir welding. Alternatively, the boundary between the first metal plate 10 and the second metal plate 20 can also be joined by solid-state diffusion.

[0030] In this embodiment, the first metal plates 10 into which the rotary tool 40 is inserted are disposed on both sides of the second metal plate 20 therebetween. Therefore, processing regions 32 are formed along the outer sides of both joints 30.

[0031] As described above, the rotary tool 40 is inserted into the first metal plate 10 so that its outer periphery is approximately aligned with the boundary. By doing so, plastic flow occurs only in the first metal plate 10, and almost no plastic flow occurs in the second metal plate 20. Therefore, a good weld 30 can be obtained with few defects such as the mixture of two types of metals or voids. Furthermore, by inserting the rotary tool 40 only on the side of the first metal plate 10, the vertical force acting on the rotary tool 40 can be greatly alleviated, preventing tool deterioration.

[0032] The first metal plate 10 on the side into which the rotary tool 40 is inserted can be made of a metal having a lower hardness than the second metal plate 20. By doing so, the rotary tool 40 is inserted only into the first metal plate 10, which has a low viscosity during plastic flow in friction stir welding. This also suppresses adhesion of metal to the rotary tool 40. This reduces the frequency of maintenance such as removing metal adhered to the rotary tool 40 and replacing the rotary tool 40. Furthermore, since less energy is required to cause plastic flow, this is advantageous for saving power.

[0033] The first metal plate 10 on the side into which the rotary tool 40 is inserted can be made of a metal with a lower melting point than the second metal plate 20. If the first metal plate 10 into which the rotary tool 40 is inserted has a higher melting point, the second metal plate 20, which is the mating material, may begin to melt when the first metal plate 10 reaches a high enough temperature to undergo plastic flow, which could result in poor welding or defects. By making the first metal plate 10 into which the rotary tool 40 is inserted a metal with a lower melting point than the second metal plate 20, the occurrence of such inconveniences can be prevented.

[0034] In this way, the dissimilar metal joining material of this embodiment joins the boundary between the first metal plate 10 and the second metal plate 20, which extends in the longitudinal direction L1 on both sides of the second metal plate 20, to form the joining portion 30.

[0035] [ manufacturing method〕 FIG. 3 shows the structure of the dissimilar metal bonding material of the present invention. manufacturing Method 1 example 3A is a plan view, and FIG. 3B is a front view, both seen from the entrance side. Therefore, in FIG. 3A, the bottom is the entrance side and the top is the exit side.

[0036] The dissimilar metal bonding material thus formed is sandwiched between upper and lower rolls 50 and rolled. The rolling direction L2 is parallel to the longitudinal direction L1 of the dissimilar metal bonding material. In other words, the rolling direction L2 is parallel to the moving direction of the rotary tool 40 in the friction stir welding described above.

[0037] In this embodiment, a dissimilar metal joint material in which two different types of metal plates 10, 20 are aligned in the width direction and joined together is rolled in the longitudinal direction.

[0038] In the rolling, the first metal plate 10, which has a relatively large elongation rate during rolling, is placed on both sides, and the second metal plate 20, which has a relatively small elongation rate, is placed therebetween, and then the joining is performed. Furthermore, in the rolling, the first metal plate 10, which has a relatively small expansion rate during rolling, is placed on both sides, and the second metal plate 20, which has a relatively large expansion rate, is placed therebetween, and then the joining is performed.

[0039] When the dissimilar metal bonding material is rolled in the longitudinal direction L1, the first metal plates 10 arranged on both sides stretch relatively more than the second metal plate 20 arranged therebetween. For this reason, the dissimilar metal bonding material is rolled while the first metal plates 10 on both sides, which stretch relatively more, apply tensile forces from both sides in the longitudinal direction to the second metal plate 20 arranged therebetween.

[0040] Furthermore, when the dissimilar metal bonding material is rolled in the longitudinal direction L1, the second metal plate 20 arranged therebetween expands relatively more than the first metal plates 10 arranged on both sides thereof. Therefore, the dissimilar metal bonding material is rolled while the second metal plate 20, which expands relatively more, applies compressive stress from the center in the width direction to the first metal plates 10 arranged on both sides thereof.

[0041] Therefore, the dissimilar metal bonding material can be effectively prevented from curving when rolled, and strict and complicated process control is not required, making it easy to realize industrially.

[0042] The compound layer between the first metal and the second metal formed during the friction stir welding method can be crushed by the rolling to form a directly joined portion of the first metal and the second metal. Even if a compound layer between the first metal and the second metal is formed during the friction stir welding method, the joining characteristics of the joined portion can be ensured by crushing the compound layer by the rolling to form a directly joined portion of the first metal and the second metal.

[0043] [Effects of the first embodiment] When the dissimilar metal bonded material of the first embodiment is rolled in the longitudinal direction, the first metal plates 10 arranged on both sides stretch relatively more than the second metal plate 20 arranged between them. Therefore, the dissimilar metal bonded material is rolled while the first metal plates 10 on both sides, which stretch relatively more, apply tensile force in the longitudinal direction to the second metal plate 20 arranged between them. Therefore, bending of the dissimilar metal bonded material when rolled is effectively prevented. Compared to conventional methods, strict and complicated process control is not required, and this method can be easily realized industrially.

[0044] Furthermore, the second metal plate 20 disposed therebetween expands relatively more than the first metal plates 10 disposed on both sides thereof. Therefore, the dissimilar metal bonding material is rolled while the second metal plate 20, which expands relatively more, applies compressive stress from the center to the first metal plates 10 disposed on both sides thereof in the width direction. Therefore, bending of the dissimilar metal bonding material when rolled is effectively prevented. Compared to conventional methods, strict and complicated process management is not required, and this method can be easily realized industrially.

[0045] In the first embodiment, the joining is friction stir welding, which is performed by inserting a rotary tool 40 into the first metal plate 10. Friction stir welding, which is performed by inserting a rotary tool 40 into the first metal plate 10, is structurally difficult to perform on thin plates. Therefore, even if friction stir welding is desired for thin plates depending on the characteristics of the joint 30, it has not been possible. The rolling method described above makes it possible to roll dissimilar metal joining materials to obtain thin plates. In other words, friction stir welding can be selected depending on the characteristics of the joint 30, and then thin plates can be obtained by rolling.

[0046] ◆ Second embodiment FIG. 4 shows the dissimilar metal bonding material of the present invention and its manufacturing Method 2 example FIG.

[0047] [Dissimilar metal bonding material] In the second embodiment of the dissimilar metal bonding material, a second metal plate 20 having a relatively small elongation rate during rolling is placed on both sides, and a first metal plate 10 having a relatively large elongation rate is placed between them, forming a bonding portion 30 by the above bonding.

[0048] In addition, in the dissimilar metal bonding material of this embodiment, a second metal plate 20 having a relatively large expansion rate during rolling is placed on both sides, and a first metal plate 10 having a relatively small expansion rate is placed between them, thereby forming a bonding portion 30 by the above-mentioned bonding.

[0049] Other than that, it is the same as the first embodiment.

[0050] [Joining method] The second embodiment can also employ a joining method using friction stir welding.

[0051] In the second embodiment, the first metal plate 10 into which the rotary tool 40 is inserted is disposed between the second metal plates 20 on both sides. Therefore, a processing region 32 is formed along the inner side of each of the joints 30.

[0052] Other than that, it is the same as the first embodiment.

[0053] [ manufacturing method〕 In the second embodiment, a dissimilar metal joint material in which two different types of metal plates 10, 20 are aligned in the width direction and joined together is also rolled in the longitudinal direction.

[0054] During the rolling, the second metal plates 20, which have a relatively small elongation rate during rolling, are placed on both sides, and the first metal plate 10, which has a relatively large elongation rate, is placed therebetween, and then the joining is performed. Furthermore, in the rolling, the second metal plate 20, which has a relatively large expansion rate during rolling, is placed on both sides, and the first metal plate 10, which has a relatively small expansion rate, is placed therebetween, and then the joining is performed.

[0055] Other than that, it is the same as the first embodiment.

[0056] [Effects of the second embodiment] When the dissimilar metal bonded material of the second embodiment is rolled in the longitudinal direction, the first metal plate 10 disposed therebetween elongates relatively more than the second metal plates 20 on either side. Therefore, the dissimilar metal bonded material is rolled while the second metal plates 20, which have a relatively small elongation rate and are disposed on both sides, apply compressive stress in the longitudinal direction to the first metal plate 10 disposed therebetween from both sides. Therefore, bending of the dissimilar metal bonded material when rolled is effectively prevented. Compared to conventional methods, strict and complicated process control is not required, and this method can be easily realized industrially.

[0057] Furthermore, the second metal plates 20 arranged on both sides expand relatively more than the first metal plate 10 arranged between them. Therefore, the dissimilar metal bonding material is rolled while the second metal plates 20 on both sides, which expand relatively more, apply compressive stress in the width direction from both sides to the first metal plate 10 arranged between them. Therefore, bending of the dissimilar metal bonding material when rolled is effectively prevented. Compared to conventional methods, strict and complicated process control is not required, and this method can be easily realized industrially.

[0058] Other than that, the same effects as those of the first embodiment are achieved. [Example]

[0059] Copper plates were placed on both sides as the second metal plate 20, and an aluminum plate was placed between them as the first metal plate 10, forming a joint 30 by the above-mentioned joining, thereby obtaining a dissimilar metal joint material, which was then rolled under the following conditions. (Rolling conditions) Cold rolling was carried out under the following conditions: Thickness before rolling: 4mm Thickness after rolling: 0.8 mm Reduction rate: 80%

[0060] Fig. 5 is a photograph of the appearance of the rolled dissimilar metal bonded material obtained as described above. It can be seen that the bending of the dissimilar metal bonded material when rolled is effectively prevented. Comparative Example

[0061] Figure 6 is a photograph of the appearance of a rolled dissimilar metal bonding material, which is made by bonding a copper plate and an aluminum plate, one on each side. It can be seen that the aluminum plate has a larger elongation rate than the copper plate, and therefore is significantly curved in the longitudinal direction. [Example]

[0062] FIG. 7 is a cross-sectional micrograph of the vicinity of a welded portion 30 of a rolled dissimilar metal welded material in which a copper plate and an aluminum plate are welded by friction stir welding. It can be seen that the compound layer of copper and aluminum formed during the friction stir welding method is crushed by the rolling, and a direct bond between copper and aluminum is formed.

[0063] [Modification] The above describes a particularly preferred embodiment of the present invention, but the present invention is not intended to be limited to the illustrated embodiment, and can be modified and implemented in various ways, and the present invention is intended to encompass various modified examples.

[0064] For example, in the above embodiment, friction stir welding is used as a method for forming the welded portion 30, but the present invention is not limited to this, and various welding methods can be used. [Explanation of symbols]

[0065] 10: First metal plate 20: Second metal plate 30: Joint 32: Processing area 40: Rotary tools 50: Rolling mill

Claims

[Claim 1] A dissimilar metal joining material in which a first metal plate and a second metal plate, which are different in type and have a longitudinal direction and a width direction, are arranged in the width direction and joined together, The joint between the first metal plate and the second metal plate is a joint in which a friction stir processed region exists on the first metal plate side, The welded portion includes a crushed compound layer of the first metal and the second metal formed by the friction stir welding, and a direct welded portion of the first metal and the second metal. A dissimilar metal bonding material characterized by:

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