Manufacturing method of components

Abstract

To suppress occurrence of a crack when a component obtained by welding is molded.SOLUTION: A manufacturing method of a component includes forming a welding component by bonding a first portion in a first plate that is a tabular component and a second portion in a second plate that is a tabular component, through laser welding. The manufacturing method of the component includes cooling a portion near the first portion in the first plate and a portion near the second portion in the second plate when laser welding is performed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a component. [Background technology]

[0002] As described in Patent Document 1, laser wobbling welding is known in which laser light is irradiated along a spiral or zigzag path to join two plate materials without using a filler metal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6495987 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the hardness of the heat-affected zone around the weld formed by laser wobbling welding is reduced, resulting in a decrease in the tensile strength of the weld. Therefore, when a member obtained by joining plate materials by laser wobbling welding is formed, cracks may occur.

[0005] In one aspect of the present disclosure, it is desirable to suppress cracking when forming the component obtained by welding. [Means for solving the problem]

[0006] One aspect of the present disclosure is a method for manufacturing a component, comprising: forming a welded component by laser welding a first portion of a first plate material, which is a plate-shaped component, and a second portion of a second plate material, which is a plate-shaped component; and cooling a portion of the first plate material near the first portion and a portion of the second plate material near the second portion during the laser welding.

[0007] According to the above configuration, it is possible to suppress a decrease in the tensile strength of the welded portion caused by laser welding in the welded member, and therefore it is possible to suppress the occurrence of cracks when forming the welded member. In one aspect of the present disclosure, the laser welding may be laser wobbling welding or laser weaving welding.

[0008] According to the above configuration, it is possible to suppress the expansion of the heat-affected zone and the decrease in hardness in the heat-affected zone, and therefore it is possible to suppress the occurrence of cracks when forming the welded member. In one embodiment of the present disclosure, the first portion may be an end surface of the first plate material, and the second portion may be an end surface of the second plate material. The first portion and the second portion may be butt-welded by laser welding.

[0009] According to the above configuration, it is possible to suppress the occurrence of cracks when forming a welded member formed by butt welding the first and second plate materials. In one aspect of the present disclosure, the welded member may have a fragile portion that is a fragile part. The method may further include shaping the welded member by pressing the welded member while pressing the fragile portion with an elastic member.

[0010] According to the above configuration, it is possible to prevent the weak portion from elongating when the welded member is formed, and therefore it is possible to prevent the weak portion from cracking when the welded member is formed. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 2 is an explanatory diagram showing first and second plate materials to be laser wobble welded as viewed from above. [Figure 2] FIG. 2 is an explanatory diagram showing first and second plate materials to be laser wobble welded as viewed from the side. [Figure 3] FIG. 1 is an explanatory diagram of press forming of a welded member. [Figure 4] FIG. 1 is an explanatory diagram of hydraulic forming of a welded member. [Figure 5] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that the embodiments of the present disclosure are not limited to the following embodiments, and various forms may be adopted as long as they fall within the technical scope of the present disclosure.

[0013] [1. Overview] The manufacturing method of this embodiment includes a welding step and a molding step, and a molded member 4 is manufactured from first and second plate materials 1 and 2 (hereinafter simply referred to as plate materials 1 and 2) which are plate-shaped members (see FIGS. 1 to 5).

[0014] As an example, the plates 1 and 2 are made of stainless steel, have a rectangular shape that extends in a plane, and have a thickness of 0.6 mm. However, the plates 1 and 2 are not limited to this, and may be made of steel other than stainless steel, or may be made of metal other than steel. Furthermore, the shapes of the plates 1 and 2 may be determined appropriately, and the thickness of the plates 1 and 2 is not limited to 0.6 mm, but may be, for example, 1 mm or less or greater than 1 mm.

[0015] Furthermore, the molded member 4 may be, for example, a large member used in a vehicle. More specifically, the molded member 4 may be, for example, a member in which a battery is disposed in an electric vehicle. Of course, the molded member 4 is not limited to this, and molded members 4 for various uses can be manufactured by the manufacturing method of this embodiment.

[0016] [2. Welding process] In the welding process, plate materials 1 and 2 are butt-welded by laser welding to form a welded member 3 (see FIGS. 1 and 2). In addition, in the welding process, laser wobbling welding is performed as an example, but the welding process is not limited to this, and laser weaving welding or laser welding other than laser wobbling welding and laser weaving welding may also be performed.

[0017] (1) Arrangement of planks In the welding process, laser wobbling welding is used to butt-weld one end face of the first plate material 1 (hereinafter referred to as the first end face 10) to one end face of the second plate material 2 (hereinafter referred to as the second end face 20) (see FIGS. 1 and 2). This results in a rectangular plate-like welded member 3 that extends in a plane. As an example, the welded member 3 may have dimensions larger than the dimensions of stainless steel plates that can be provided by manufacturers. Of course, this is not a limitation, and the size of the welded member 3 can be determined as appropriate.

[0018] Specifically, first, the plate materials 1 and 2 are placed on a work table with the plate materials 1 and 2 extending horizontally and with the first and second end faces 10 and 20 (hereinafter simply referred to as end faces 10 and 20) abutting each other. The plate materials 1 and 2 may also be placed on the work table with a small gap (for example, a gap of about 1 mm) formed between the first end face 10 and the second end face 20. The upper surfaces of the plate materials 1 and 2 placed on the work table are referred to as first surfaces 11 and 21.

[0019] (2) Arrangement of cooling components Next, cooling members 6 are arranged on each of the first surfaces 11 and 12 of the plates 1 and 2 along the end faces 10 and 20 (see FIGS. 1 and 2 ). The cooling members 6 are arranged on the plates 1 and 2 from the first ends 10A and 20A to the second ends 10B and 20B of the end faces 10 and 20, spaced apart from the end faces 10 and 20. The cooling members 6 arranged on each of the plates 1 and 2 are located near the end faces 10 and 20. That is, these cooling members 6 may be located near the welded zones 30 (described below) formed near the end faces 10 and 20, and more specifically, they may be located near the heat-affected zones 31 (described below) formed near the end faces 10 and 20. Furthermore, these cooling members 6 may be arranged, for example, about 20 mm away from the end faces 10 and 20. The distance between each cooling member 6 and the end faces 10 and 20 may be less than 20 mm as long as they do not hit the shielding gas nozzle. Furthermore, as long as a cooling effect is obtained, the distance between each cooling member 6 and the end faces 10, 20 may be greater than 20 mm. Therefore, a gap is formed between the cooling member 6 arranged on the first plate 1 and the plate arranged on the second plate 2, and the end faces 10, 20 are located in this gap.

[0020] Here, the cooling member 6 arranged on each of the plate materials 1 and 2 may be configured, for example, as multiple copper plates lined up in a row along the end faces 10 and 20, or as a single elongated copper plate extending along the end faces 10 and 20.

[0021] Furthermore, the cooling member 6 may be configured as a flow path for a cooling medium such as water, and cooling may be performed by flowing the cooling medium through the flow path. Specifically, for example, a cooling medium flow path may be provided inside the multiple copper plates that make up the cooling member 6, and cooling may be performed by flowing the cooling medium through the flow path.

[0022] [(3) Laser wobbling welding] Then, while cooling is performed by the cooling member 6, butt welding is performed on the first and second end faces 10, 20 of the plate materials 1, 2 by laser wobbling welding (see FIGS. 1 and 2). Specifically, a laser head 50 of the laser device 5 irradiates a laser beam L onto the area around the end faces 10, 20 on the first surfaces 11, 21 of the plate materials 1, 2. The laser device 5 performs butt welding from the first ends 10A, 20A of the end faces 10, 20 to the second ends 10B, 20B by moving the laser head 50. At this time, the laser device 5 adjusts the irradiation direction of the laser beam L using an adjustment mechanism (e.g., a galvanometer mirror) provided inside the laser head 50 so that the irradiation position moves along a spiral path, for example. Of course, this is not a limitation, and the laser beam L may be irradiated along a zigzag path, for example. Furthermore, for example, instead of changing the irradiation direction of the laser light L, the irradiation position of the laser light L may be moved by displacing the positions of the plate materials 1 and 2 by moving the work table.

[0023] Furthermore, after butt welding is performed on the first surfaces 11, 21 of the plate materials 1, 2 by laser wobbling welding, the plate materials 1, 2 may be turned over and placed on a workbench with the second surfaces 12, 22 facing upward. Laser wobbling welding may then be performed on the areas around the end surfaces 10, 20 on the second surfaces 12, 22 of the plate materials 1, 2 in the same manner as on the first surfaces 11, 21, and butt welding may be performed from the second surfaces 12, 22 side. Of course, this is not a limitation, and laser wobbling welding may be performed only on the first surfaces 11, 21 of the plate materials 1, 2.

[0024] In the plate materials 1 and 2, the material is melted by irradiation with laser light L, and the melted material solidifies, forming a welded portion 30 around the end faces 10 and 20. The welded portion 30 extends from the first end to the second end of the welded member 3. In addition, heat-affected zones 31 are formed on both sides of the welded portion 30 in the welded member 3.

[0025] [3. Molding process] In the molding process, molding is performed on the welded member 3 while the weak portion, which is a weak part of the welded member 3, is pressed by an elastic member, thereby forming a molded member 4 (see FIG. 3). Note that the weak portion may be, for example, the welded portion 30 and the heat-affected zone 31 produced by laser wobbling welding.

[0026] In the forming process, for example, press forming is performed using a punch 7 and a lower die 8 (see FIG. 3). That is, first, the workpiece 3 to be welded is placed in the lower die 8, and then the pressing surface 70 of the punch 7 is brought into contact with the workpiece 3 to be welded, and the punch 7 presses the workpiece 3 to be welded from above toward the lower die 8.

[0027] An elastic member 71 (e.g., rubber) is disposed on the pressing surface 70 of the punch 7. The elastic member 71 is provided on the pressing surface 70 from a position where it abuts against a first end of the welded portion 30 and the heat-affected zone 31 to a position where it abuts against a second end. When the punch 7 presses the welded member 3, the elastic member 71 abuts against and presses the entire welded portion 30 and the heat-affected zone 31 of the welded member 3. When the punch 7 presses the welded member 3, the elastic member 71 may press only the entire welded portion 30 or only the entire heat-affected zone 31, or may press only specific portions of the welded portion 30 and / or the heat-affected zone 31 that are prone to cracking. In addition to or instead of the elastic member 71 of the punch 7, an elastic member provided on the lower die 8 may also press the weak portions of the welded member 3 in a similar manner.

[0028] Alternatively, the welded member 3 may be formed by, for example, hydraulic forming (see FIG. 4). That is, the welded member 3 may be placed in a lower mold 8 filled with a liquid 80 such as water, and the welded member 3 may be pressed from above by a punch 7 configured in the same way as that used in press forming. Similarly, the weakened portion of the welded member 3 may be pressed by an elastic member 71. With this configuration, the same effect can be obtained.

[0029] Furthermore, instead of the elastic member 71 provided on the punch 7, the fragile portion of the welded member 3 may be pressed by a plate-shaped elastic member attached to the fragile portion. That is, the welded member 3 may be placed in the lower die 8 with a plate-shaped elastic member attached to the welded portion 30 and / or the heat-affected zone 31. In this case, the surface of the welded member 3 to which the elastic member is attached may be located on the upper side (in other words, the punch side). Furthermore, if press forming is performed, the surface of the welded member 3 to which the elastic member is attached may be located on the lower side (in other words, the lower die 8 side). Then, the welded member 3 may be pressed by a punch not provided with the elastic member 71, thereby forming the welded member 3 with the fragile portion pressed by the elastic member.

[0030] [4. Effects] (1) In some cases, multiple thin stainless steel plates, each about 0.6 mm thick, are joined by laser welding to form a large plate, and the large plate is then shaped. In such cases, if the laser beam output during laser welding is high (for example, about 2 to 7 kW), thermal distortion and melt-through can make it difficult or impossible to weld the thin plates together.

[0031] Furthermore, when a load is applied to a surface of a stainless steel plate, the material flows along the surface rather than in the direction of the load. Furthermore, the hardness of the welded portion created by laser welding increases, while the hardness of the heat-affected zone around the weld decreases, resulting in variations in the elongation of the material around the welded portion and the heat-affected zone. Therefore, the tensile strength of the welded portion and the heat-affected zone is lower than the tensile strength of other parts not affected by the laser welding. Therefore, even if these thin plates can be welded, cracks may occur in the welded portion and the heat-affected zone when the large plate obtained by welding is formed.

[0032] In contrast, according to the above embodiment, when the end faces 10, 20 of the plate materials 1, 2 are joined by laser wobbling welding, the vicinity of the end faces 10, 20 of the plate materials 1, 2 is cooled by the cooling member 6. This allows the heat input by the laser wobbling welding to be removed early, thereby suppressing burn-through and distortion of the plate materials 1, 2 and enabling good laser wobbling welding.

[0033] Furthermore, early removal of heat input by the cooling member 6 can promote refinement of the structure in the welded zone 30 and the heat-affected zone 31, and can suppress expansion of the heat-affected zone 31 and a decrease in hardness of the heat-affected zone 31. This can suppress a decrease in the tensile strength of the heat-affected zone 31 and the welded zone 30 of the welded member 3, and promotes that the tensile strength and the tensile strength of other parts other than the heat-affected zone 31 and the welded zone 30 become approximately the same. This can therefore suppress cracks from occurring in the welded zone 30 and the heat-affected zone 31 of the welded member 3 during the forming process, allowing the welded member 3 to be formed appropriately.

[0034] (2) In addition, in the welding process, the end faces 10, 20 of the plate materials 1, 2 are butt-welded by laser wobbling welding. This can promote the refinement of the structure of the welded portion 30 and the heat-affected portion 31, and can suppress the expansion of the heat-affected portion 31 and the decrease in hardness of the heat-affected portion 31. This can suppress the decrease in tensile strength of the heat-affected portion 31 and the welded portion 30 of the welded member 3, and as a result, the occurrence of cracks in the welded member 3 during the forming process can be suppressed.

[0035] (3) In the forming process, the welded member 3 is formed while the welded portion 30 and the heat-affected portion 31 of the welded member 3 are pressed by the elastic member 71. This prevents the material from moving in a direction along the surface of the welded member 3 at the welded portion 30 and the heat-affected portion 31. This prevents elongation at the welded portion 30 and the heat-affected portion 31, and prevents cracks from occurring at the welded portion 30 and the heat-affected portion 31 when the welded member 3 is formed.

[0036] 5. Other Embodiments (1) In the molding process of the above embodiment, in addition to or instead of pressing the welded portion 30 and the heat-affected portion 31, weak portions of the welded member 3 other than the welded portion 30 and the heat-affected portion 31 may be pressed by an elastic member.

[0037] (2) In the welding process of the above embodiment, butt welding is performed. However, instead, for example, fillet welding or lap welding may be performed. Specifically, the first plate 1 may be disposed so that the second surface 22 of the second plate 2 abuts against the first surface 11 of the first plate 1. Then, fillet welding may be performed between the end surface 20 of the second plate 2 and the first surface 11 of the first plate 1, or lap welding may be performed to join the first surface 11 of the first plate 1 and the second surface 22 of the second plate 2 along the end surface 20 of the second plate 2. In this case, as in the above embodiment, a cooling member 6 may be disposed along the end surface 20 from the first end to the second end of the end surface 20, and fillet welding or lap welding may be performed while cooling the area around the end surface 20 of the first plate 1 and the area around the end surface 20 of the second plate 2.

[0038] (3) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0039] [7. Technical Ideas Disclosed in the Present Specification] [Item 1] A method for manufacturing a component, comprising: forming a welded member by joining a first portion of a first plate material, which is a plate-shaped member, and a second portion of a second plate material, which is a plate-shaped member, by laser welding; When performing the laser welding, cooling a portion of the first plate material near the first portion and a portion of the second plate material near the second portion; A method for manufacturing a member comprising:

[0040] [Item 2] A method for manufacturing the member according to item 1, The laser welding is laser wobbling welding or laser weaving welding. Manufacturing method of components.

[0041] [Item 3] A method for producing a member according to item 1 or 2, the first portion is an end surface of the first plate material, the second portion is an end surface of the second plate material, The first portion and the second portion are butt-welded by the laser welding. Manufacturing method of components.

[0042] [Item 4] A method for manufacturing a member according to any one of items 1 to 3, The welded member has a weak portion that is a weak part, Pressing the welding member while pressing the fragile portion with an elastic member, thereby forming the welding member; The method for manufacturing a member further comprises: [Explanation of symbols]

[0043] 1...first plate material, 10...first end surface, 10A...first end, 10B...second end, 11...first surface, 12...second surface, 2...second plate material, 20...second end surface, 20A...first end, 20B...second end, 21...first surface, 22...second surface, 3...welding member, 30...welding portion, 31...heat-affected portion, 4...molding member, 5...laser device, 50...laser head, L...laser light, 6...cooling member, 7...punch, 70...pressing surface, 71...elastic member, 8...lower mold, 80...liquid.

Claims

[Claim 1] A method for manufacturing a component, comprising: forming a welded member by joining an end surface of a first plate material, which is a plate-shaped member made of stainless steel and having a plate thickness of 1 mm or less, and an end surface of a second plate material, which is a plate-shaped member made of stainless steel and having a plate thickness of 1 mm or less, by butt welding using laser welding; When performing the laser welding, cooling a portion near an end surface of the first plate material and a portion near an end surface of the second plate material; Pressing the welded member while pressing a weak portion, which is a weak portion of the welded member, with an elastic member, thereby forming the welded member; Equipped with The laser welding is laser wobbling welding, the fragile portion is a welded portion and a heat-affected zone in the welded member, The welded portion is a portion formed by solidifying the material melted by the laser wobbling welding, The heat-affected zone is generated around the welded portion by the laser wobbling welding. Manufacturing method of components.

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