Method for manufacturing structural member

Abstract

To provide a method for manufacturing a structural member capable of manufacturing a high-quality structural member by easily and smoothly joining extruded materials to each other.SOLUTION: A method for manufacturing a structural member includes the steps of: disposing a plurality of extruded panels 11A to 11D provided with surplus regions Ar at both ends in advance on a base plate 31 with edge portions abutted against each other; fixing the extruded panels 11A to 11D to the base plate 31 by bolts 39 inserted into through-holes 19 of the surplus regions Ar, friction-stir-welding the edge portions of the extruded panels 11A to 11D to each other on a front surface side so that a start point and an end point are disposed on the surplus regions Ar; reversing the plurality of extruded panels 11A to 11D to dispose again them on the base plate 31; fixing the extruded panels 11A to 11D to the base plate 31 by the bolts 39 inserted into the through-holes 19 of the surplus regions Ar; friction-stir-welding the edge portions of the extruded panels 11A to 11D to each other on the back surface side so that the start point and the end point are disposed on the surplus regions Ar; and removing the surplus regions Ar by detaching the plurality of the extruded panels 11A to 11D joined to each other from the base plate 31.SELECTED DRAWING: Figure 6A

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a structural member.

Background Art

[0002] Conventionally, there has been a demand for improving the safety of passengers in vehicles, and for this purpose, the strength of vehicle bodies has been improved. On the other hand, against the backdrop of the intensification of problems such as global warming, the movement to improve the fuel efficiency of automobiles has been accelerating. It is known that weight reduction of the vehicle body is effective for improving fuel efficiency. In addition, for the above-mentioned environmental improvement, the development of vehicles that run on electricity (including electric vehicles, hybrid vehicles, etc.) and devices such as self-propelled robots has been progressing. In a battery system mounted on such a vehicle or device, a configuration may be adopted in which a large number of batteries (cells, battery cells) are housed in a battery tray made of a structural member in which aluminum extruded materials are joined.

[0003] By the way, as a technique for joining members such as extruded materials, it is known to butting the members together and performing friction stir joining with a friction stir tool. In this friction stir joining, there is a possibility that an incomplete joining portion where the joining is insufficient may occur at the start and end of the joining. Therefore, when friction stir joining members, tab plates are arranged on the extension lines at both ends of the butting portion of the members, and the start and end of the friction stir joining are positioned on the tab plates, thereby suppressing the occurrence of incomplete joining portions at the joint (see, for example, Patent Documents 1 to 3).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the technique using tab plates, the tab plates must be positioned and arranged on the members without gaps and steps, which requires labor. In addition, the joining conditions change at the boundary between the member and the tab plate, and there is a risk that the joining quality at both ends of the joint part may deteriorate. Furthermore, when joining the front and back of the butting part, it is necessary to reposition and arrange the tab plates at both ends of the joint part, which requires labor for the joining operation.

[0006] Therefore, an object of the present invention is to provide a method for manufacturing a structural member capable of easily and smoothly joining extruded materials to manufacture a high-quality structural member.

Means for Solving the Problems

[0007] The present invention is configured as follows. A manufacturing method for manufacturing a structural member by joining the edges of a plurality of extrusion panels made of extruded materials, a first arranging step of arranging a plurality of the extrusion panels provided with surplus regions having through holes at both ends in advance on a base plate with the edges butted against each other; a first fixing step of inserting a fastening member into the through hole of the surplus region and fixing the extrusion panel to the base plate by the fastening member; a first joining step of friction stir joining the edges of the extrusion panels butted against each other on the surface side of the extrusion panel by a friction stir tool such that the start point and the end point are the surplus regions; a second arranging step of releasing the fixing of the plurality of extrusion panels joined on the surface side to the base plate, inverting them, and arranging the extrusion panels on the base plate again; a second fixing step of inserting a fastening member into the through hole of the surplus region and fixing the extrusion panel to the base plate by the fastening member; On the back side of the extrusion panel, a second joining step of friction stir joining the mutually abutting edges of the extrusion panel by a friction stir tool such that the start point and the end point are the surplus regions; A surplus region removing step of removing the surplus regions by removing the plurality of joined extrusion panels from the base plate; comprising A method for manufacturing a structural member.

Advantages of the Invention

[0008] According to the present invention, high-quality structural members can be manufactured by easily and smoothly joining extruded materials together.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 6C

Figure 6D

Figure 6E

Figure 6F

Figure 6G

Figure 6H

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a structural member 100 manufactured by the manufacturing method of the structural member of this example. FIG. 2 is an enlarged front view of a part of the structural member 100 shown in FIG. 1.

[0011] As shown in FIGS. 1 and 2, the structural member 100 manufactured by the manufacturing method of the structural member according to this configuration example is a plate-shaped structure, and is composed of extrusion panels 11A to 11D made of a plurality (in this example, four as an example) of extruded materials. The structural member 100 is configured by joining the edges along the extrusion direction of the extrusion panels 11A to 11D to each other.

[0012] As the extrusion panels 11A to 11D, plate-shaped extruded materials made of aluminum or an aluminum alloy are used. As the aluminum alloy used as the extrusion panels 11A to 11D, aluminum alloys of the 5000 series, 6000 series, 7000 series, etc. according to the JIS or AA standard are preferable in terms of having excellent strength and being able to be made thinner. The hollow extruded shapes of these aluminum alloys can be preferably used those manufactured by appropriately combining quality control processes such as casting (DC casting method or continuous casting method), homogenization heat treatment, hot extrusion, solution treatment and quenching treatment, and artificial aging treatment if necessary. According to this, the structural member 100 can be made into a high-strength configuration while being lightweight.

[0013] In the extrusion panels 11A to 11D, one or a plurality of hollow portions 13 are formed at the center in the thickness direction thereof. The extrusion panels 11A to 11D are, for example, thin plates having a thickness of 15 mm or less. The thickness of the hollow portion 13 of the extrusion panels 11A to 11D is preferably about half of the thickness of the extrusion panels 11A to 11D.

[0014] The structural member 100 shown in FIG. 2 is joined at the joint portion 21 where the edges of the extrusion panels 11B and 11C are butted against each other. Similarly, the extrusion panel 11A and the extrusion panel 11B, and between the extrusion panel 11C and the extrusion panel 11D are also joined. The extrusion panels 11A to 11D have protruding pieces 15 and stepped portions 17 at the edges on the side of the joint portion 21 facing each other. The pair of protruding pieces 15 are overlapped with each other in the plate thickness direction. Then, in each joint portion 21 of the extrusion panels 11A to 11D, the protruding piece 15 of one extrusion panel abuts against the wall portion 17a forming the stepped portion 17 of the other extrusion panel, and the butting portions on the front and back are joined. Thereby, the joint portion 21 has a first joint portion 23 formed on the front surface side which is one surface, and a second joint portion 25 formed on the back surface side which is the other surface. Each of the first joint portion 23 and the second joint portion 25 is joined by friction stir welding using a friction stir tool.

[0015] In the structural member 100 of this configuration, the butting portions of the extrusion panels 11A to 11D on the front and back are joined with a well-balanced and stable joint strength at the first joint portion 23 on the front surface side and the second joint portion 25 on the back surface side. Therefore, sufficient strength can be ensured at the joint portion 21 of the structural member 100 and its periphery.

[0016] Next, a jig 30 used when joining the extrusion panels 11A to 11D to each other will be described. FIG. 3 is a perspective view for explaining the jig 30 used in the manufacturing method of the structural member of this example. FIG. 4 is a plan view of the jig 30 shown in FIG. 3. FIG. 5 is a cross-sectional view taken along line V-V in FIG. 4.

[0017] As shown in FIGS. 3 to 5, the jig 30 includes a base plate 31, a plurality of spacers 33, and a plurality of contact plates 35.

[0018] The base plate 31 is formed in a flat plate shape with a smooth upper surface. The base plate 31 is formed in a rectangular shape in plan view, and on its upper surface, the extrusion panels 11A to 11D to be joined to each other are arranged side by side along the longitudinal direction of the base plate 31. These extrusion panels 11A to 11D are aligned with their extrusion directions aligned. The base plate 31 has a plurality of bolt holes 31a formed by female screws at intervals in the longitudinal direction near the edge portion in the short side direction. A bolt (fastening member) 39 for fixing the extrusion panels 11A to 11D to the base plate 31 is fastened to the bolt hole 31a.

[0019] Each spacer 33 is a flat plate-like plate material and is inserted into the hollow portion 13 from both ends in the extrusion direction of the extrusion panels 11A to 11D. Each spacer 33 is inserted into the hollow portion 13 of the extrusion panels 11A to 11D with a part of it protruding from the end portion in the extrusion direction of the extrusion panels 11A to 11D. Each spacer 33 is formed with an insertion hole 33a penetrating through the front and back.

[0020] Each contact plate 35 is a flat plate-like plate material and is arranged on the upper surface side at both ends in the extrusion direction of the extrusion panels 11A to 11D. The contact plate 35 is formed with an insertion hole 35a corresponding to the hollow portion 13 of each of the extrusion panels 11A to 11D. Here, the total number (6) of the insertion holes 35a of the contact plates 35 arranged on one side in the above-described extrusion direction is the same as the number of the hollow portions 13. That is, one insertion hole 35a is formed in the contact plate 35 arranged on the upper surface side of the extrusion panels 11A and 11D having one hollow portion 13, and two insertion holes 35a are formed in the contact plates 35 arranged on the upper surfaces of the extrusion panels 11B and 11C having two hollow portions 13 at intervals with the same pitch as the hollow portion 13.

[0021] Next, the case of manufacturing the structural member 100 using the above jig 30 will be described. Figures 6A to 6H are explanatory diagrams for explaining the procedure of joining the extrusion panels 11A to 11D to form the structural member 100.

[0022] (First Arrangement Step) As shown in FIG. 6A, surplus regions Ar are provided in advance at both ends in the extrusion direction of each of the extrusion panels 11A to 11D, and through holes 19 are formed in these surplus regions Ar. As the surplus region Ar, it is preferable to set the dimension W in the joining direction by the friction stir tool to be 10 times or more the wall thickness at the joining location. Further, the through hole 19 is formed, for example, at the center in the joining direction of the surplus region Ar at the center in the width direction of the hollow portion 13 (see FIG. 4). In this way, the extrusion panels 11A to 11D provided with the surplus regions Ar having the through holes 19 are arranged on the base plate 31 parallel to the extrusion direction, and the edge portions in the arrangement direction of each of the extrusion panels 11A to 11D are butted against each other. Note that the bolt holes 31a (see FIG. 5) of the base plate 31 are formed at positions communicating with the through holes 19 of the plurality of extrusion panels 11A to 11D arranged on the upper surface of the base plate 31. Then, the extrusion panels 11A to 11D are arranged on the base plate 31 with their through holes 19 communicating with the bolt holes 31a of the base plate 31.

[0023] (First Fixing Step) As shown in FIG. 6B, spacers 33 are inserted into the hollow portions 13 from both ends in the extrusion direction of the extrusion panels 11A to 11D arranged on the base plate 31, and the insertion holes 33a of these spacers 33 are communicated with the through holes 19 of the extrusion panels 11A to 11D.

[0024] Furthermore, a contact plate 35 is disposed on the upper surface of the extrusion panels 11A to 11D at both ends, which is opposite to the base plate 31, and the insertion holes 35a of these contact plates 35 are communicated with the through holes 19 of the extrusion panels 11A to 11D. Then, bolts 39 are inserted into the mutually communicated insertion holes 33a, 35a and through holes 19 from the upper side (perpendicular to the plate surface), and fastened to the bolt holes 31a of the base plate 31. Thereby, the extrusion panels 11A to 11D disposed on the base plate 31 are fixed to the base plate 31. At this time, since the spacers 33 are inserted into the hollow portions 13 of the extrusion panels 11A to 11D, deformation of the hollow portions 13 due to fastening of the bolts 39 is suppressed. Also, the contact plate 35 suppresses the occurrence of damage to the extrusion panels 11A to 11D due to contact with the bolts 39. And the extrusion panels 11A to 11D are pressed against the base plate 31 and arranged in a smooth state with each other by being fastened and fixed to the base plate 31 with bolts 39.

[0025] (First joining step) As shown in FIG. 6C, a joint portion 21 formed by butting the edges of the extrusion panels 11A to 11D is friction stir joined on the surface side by a friction stir tool. Thereby, a first joint portion 23 is formed in the joint portion 21 for each of the extrusion panels 11A to 11D, and they are joined to each other on the surface side. Here, the friction stir joining is performed such that the start point and the end point of the friction stir tool become the surplus region Ar. Thereby, in the first joint portion 23, the start and end points Pse of the friction stir joining are arranged in the surplus region Ar described above.

[0026] (Second arrangement step) The bolts 39 fixing the extrusion panels 11A to 11D are loosened to release the fixing of the extrusion panels 11A to 11D to the base plate 31, and the spacers 33 and the contact plates 35 are removed. After removing the extrusion panels 11A to 11D from the base plate 31, as shown in FIG. 6D, the extrusion panels 11A to 11D joined at the first joint portion 23 on the surface side are inverted and arranged again on the base plate 31. Then, the through holes 19 of the extrusion panels 11A to 11D are communicated with the bolt holes 31a (see FIG. 5) of the base plate 31.

[0027] (Second Fixing Step) As shown in Fig. 6E, insert spacers 33 into the hollow portion 13 from both ends of the extrusion panels 11A to 11D in the extrusion direction, and place the contact plates 35 on the upper surfaces opposite to the base plates 31 at both ends of the extrusion panels 11A to 11D in the extrusion direction. Then, communicate the insertion holes 33a and 35a of the spacers 33 and the contact plates 35 with the respective through holes 19 (Fig. 6D) of the extrusion panels 11A to 11D. After that, insert bolts 39 into the insertion holes 33a, 35a and the through holes 19 that are communicated with each other from the upper side (perpendicular to the plate surface), and fasten them to the bolt holes 31a of the base plate 31. Thereby, the extrusion panels 11A to 11D arranged on the base plate 31 are fixed to the base plate 31. Also at this time, the deformation of the hollow portion 13 due to the fastening of the bolts 39 is suppressed by the spacers 33, and the occurrence of damage to the extrusion panels 11A to 11D due to contact with the bolts 39 is suppressed by the contact plates 35. Further, by fixing the extrusion panels 11A to 11D to the base plate 31 with the bolts 39, each of the extrusion panels 11A to 11D is pressed against the base plate 31, and the warp generated when the surface side was joined in the first joining step is returned to the opposite side and arranged in a smooth state.

[0028] (Second Joining Step) As shown in Fig. 6F, on the back side of the extrusion panels 11A to 11D, a joint portion 21 formed by butting the edges against each other is friction stir joined by a friction stir tool. Thereby, a second joint portion 25 is formed in the joint portion 21 for each of the extrusion panels 11A to 11D, and they are joined to each other on the back side. Also at this time, the friction stir joining is performed so that the starting point and the ending point of the friction stir tool become the surplus region Ar. Thereby, for the second joint portion 25, the start and end points Pse of the friction stir joining are arranged in the surplus region Ar.

[0029] (Surplus Region Removal Step) Loosen the bolts 39 that fix the extrusion panels 11A to 11D joined on the front and back shown in Fig. 6F, release the fixation of the extrusion panels 11A to 11D to the base plate 31, and remove the spacers 33 and the backing plates 35. As shown in Fig. 6G, when the extrusion panels 11A to 11D are removed from the base plate 31, as shown in Fig. 6H, cut and remove the surplus regions Ar of the extrusion panels 11A to 11D where the start and end points Pse of the first joint portion 23 and the second joint portion 25 are formed at their boundary portions. Thereby, a structural member 100 in which a plurality of extrusion panels 11A to 11D are friction stir joined on the front and back is obtained. Note that the removed surplus region Ar is recycled and formed into an extrusion panel or the like again, for example. At this time, the surplus region Ar having the friction stir joint portion is made of the same material as the extrusion panels 11A to 11D, and since there is no mixing of other metals, it can be formed into an extrusion panel again without removing impurities or the like.

[0030] As described above, according to the manufacturing method of the structural member according to this example, friction stir joining is performed such that the start point and the end point of the friction stir joining by the friction stir tool are arranged in the surplus regions Ar provided in advance at both ends of the extrusion panels 11A to 11D, and the surplus region Ar is removed after joining. Therefore, the occurrence of incomplete joint portions in the joint portion 12 of the manufactured structural member 100 can be suppressed. Further, since the bolt 39 is inserted into the through hole 19 of the surplus region Ar and the extrusion panels 11A to 11D are fixed to the base plate 31 with this bolt 39, friction stir joining can be performed in a stable state. Thereby, compared with the method of arranging tab plates at the positions of the start point and the end point of the friction stir joining and performing friction stir joining, a high-quality structural member 100 without incomplete joint portions can be easily manufactured. That is, a high-quality structural member 100 in which the extrusion panels 11A to 11D are joined on the front and back can be easily manufactured while suppressing costs.

[0031] Further, by setting the dimension W in the joining direction of the surplus region Ar by the friction stir tool to be 10 times or more the wall thickness at the joining portion, the start and end points Pse of the friction stir joining by the friction stir tool can be smoothly arranged in the surplus region, and a high-quality structural member 100 can be manufactured.

[0032] Moreover, since the spacers 33 are inserted into the hollow portions 13 of the extrusion panels 11A to 11D and the extrusion panels 11A to 11D are fixed to the base plate 31 by bolts 39, deformation in the hollow portions 13 during fastening of the bolts 39 can be suppressed.

[0033] Also, the contact plate 35 can suppress the occurrence of scratches or the like on the extrusion panels 11A to 11D due to contact with the bolts 39. Moreover, the fastening force of the bolts 39 can be dispersed to fix the extrusion panels 11A to 11D to the base plate 31 in a stable state, and friction stir joining can be performed smoothly.

[0034] In addition, in the above embodiment, the case where the extrusion panels 11A to 11D having the hollow portions 13 are joined to manufacture the structural member 100 is illustrated. However, the present invention is also applicable to the case where the solid extrusion panels 11A to 11D without the hollow portions 13 are joined to manufacture the structural member 100. In this case, the extrusion panels 11A to 11D are fixed to the base plate 31 and friction stir joined without using the spacers 33.

[0035] Also, in the above embodiment, the extrusion panels 11A to 11D are fixed to the base plate 31 by bolts 39. However, the fixing of the extrusion panels 11A to 11D to the base plate 31 is not limited to fastening by bolts 39, and may be fixed by various fastening methods using clamps, pins, or the like.

[0036] As described above, the present invention is not limited to the above embodiments, and it is also contemplated by the present invention that those skilled in the art can make changes and applications based on combining each configuration of the embodiments, the description of the specification, and well-known techniques, and such are included in the scope for which protection is sought.

[0037] As described above, the following matters are disclosed in this specification. (1) A manufacturing method for manufacturing a structural member by joining the edges of a plurality of extrusion panels made of extruded materials, a first arranging step of arranging a plurality of the extrusion panels provided with surplus regions having through holes at both ends in advance on a base plate with the edges butted against each other; A first fixing step of inserting a fastening member into the through hole of the surplus area and fixing the extrusion panel to the base plate with the fastening member; A first joining step of friction stir joining, on the surface side of the extrusion panel, the edges of the extrusion panel that abut each other with a friction stir tool such that the start point and the end point are the surplus areas; A second arranging step of releasing the fixing of the plurality of extrusion panels joined on the surface side to the base plate, inverting them, and arranging the extrusion panels on the base plate again; Inserting a fastening member into the through hole of the surplus area, and using the fastening member to fix the extrusion panel to the base plate in a second fixing step; A second joining step of friction stir joining, on the back surface side of the extrusion panel, the edges of the extrusion panel that abut each other with a friction stir tool such that the start point and the end point are the surplus areas; A surplus area removing step of removing the surplus area by removing the plurality of extrusion panels joined to each other from the base plate; A method for manufacturing a structural member, including the above steps. According to this method for manufacturing a structural member, friction stir joining is performed such that the start point and the end point of the friction stir joining by the friction stir tool are arranged in the surplus areas provided in advance at both ends of the extrusion panel, and the surplus area is removed after joining, so that the occurrence of incomplete joining portions at the joint portions of the manufactured structural member can be suppressed. Further, a fastening member is inserted into the through hole of the surplus area, and the extrusion panel is fixed to the base plate with this fastening member, so that friction stir joining can be performed in a stable state. Thereby, compared with the method of arranging tab plates at the positions of the start point and the end point of the friction stir joining and performing friction stir joining, a high-quality structural member without incomplete joining portions can be easily manufactured. That is, a high-quality structural member in which the extrusion panels are joined back to back can be easily manufactured while suppressing costs. (2) The method for manufacturing a structural member according to (1), wherein the dimension of the surplus area in the joining direction by the friction stir tool is 10 times or more the wall thickness at the joining portion. According to the manufacturing method of this structural member, the start and end points of friction stir welding by a friction stir tool can be smoothly arranged in the surplus area, and a high-quality structural member can be manufactured. (3) The extrusion panel has a hollow portion, In the first fixing step and the second fixing step, a spacer is inserted into the hollow portion at the fixing position of the extrusion panel to the base plate by the fastening member, and the manufacturing method of the structural member according to (1) or (2). According to the manufacturing method of this structural member, since a spacer is inserted into the hollow portion and the extrusion panel is fixed to the base plate by a fastening member, deformation in the hollow portion during fastening of the fastening member can be suppressed. (4) In the first fixing step and the second fixing step, a backing plate is arranged on the side opposite to the base plate at the fixing position of the extrusion panel by the fastening member, and the manufacturing method of the structural member according to (1) or (2). (5) In the first fixing step and the second fixing step, a backing plate is arranged on the side opposite to the base plate at the fixing position of the extrusion panel, and the manufacturing method of the structural member according to (3). According to the manufacturing methods of the structural members in (4) and (5) above, the occurrence of scratches and the like on the extrusion panel due to contact with the fastening member can be suppressed by the backing plate. In addition, the fastening force of the fastening member can be dispersed to fix the extrusion panel to the base plate in a stable state, and friction stir welding can be performed smoothly.

Explanation of symbols

[0038] 11A, 11B, 11C, 11D Extrusion panel 19 Through hole 23 First joint 25 Second joint 31 Base plate 33 Spacer 35 Backing plate 39 Bolt (fastening member) 100 Structural member Ar Surplus area Pse Start and end points

Claims

1. A manufacturing method for manufacturing a structural member by joining the edges of a plurality of extrusion panels made of extruded materials, a first arranging step of arranging a plurality of the extrusion panels, each having a surplus region with a through hole provided at both ends in advance, on a base plate with the edges butted against each other; a first fixing step of inserting a fastening member into the through hole of the surplus region and fixing the extrusion panel to the base plate with the fastening member; a first joining step of friction stir joining the edges of the extrusion panels butted against each other on the surface side of the extrusion panel with a friction stir tool such that the start point and the end point are the surplus regions; a second arranging step of releasing the fixing of the plurality of extrusion panels joined on the surface side to the base plate, inverting them, and arranging the extrusion panels on the base plate again; a second fixing step of inserting a fastening member into the through hole of the surplus region and fixing the extrusion panel to the base plate with the fastening member; a second joining step of friction stir joining the edges of the extrusion panels butted against each other on the back side of the extrusion panel with a friction stir tool such that the start point and the end point are the surplus regions; a surplus region removing step of removing the joined plurality of extrusion panels from the base plate and removing the surplus region; including a manufacturing method of a structural member.

2. The dimension of the surplus region in the joining direction by the friction stir tool is 10 times or more the wall thickness at the joining portion. The manufacturing method of the structural member according to Claim 1.

3. The extrusion panel has a hollow portion. In the first fixing step and the second fixing step, a spacer is inserted into the hollow portion at the fixing position of the extrusion panel to the base plate by the fastening member. The manufacturing method of the structural member according to Claim 1.

4. In the first fixing step and the second fixing step, a backing plate is disposed on the side opposite to the base plate at the fixing position of the extrusion panel to the base plate by the fastening member. The method for manufacturing a structural member according to claim 1 or 2.

5. In the first fixing step and the second fixing step, a backing plate is disposed on the side opposite to the base plate at the fixing position of the extrusion panel. The method for manufacturing a structural member according to claim 3.

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