JPH10328856A - Friction welding method and weld joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effect friction welding for a hollow member such as an extruded shape or a honeycomb panel without causing deformation or weld defects in a work. SOLUTION: In continuously welding two extruded shapes 1, 2 in the weld line direction by inserting into the weld zone a welding tool 3 constituted of a metallic rod that is formed with a material essentially harder than one for the extruded shapes 1, 2, moving the tool while it is rotated, and thereby generating a frictional heat; the end 12 of one shape 1 and that 13 of the other shape 2 are arranged so that their projecting parts 12a, 13a are superposed on each other, with the welding tool 3 positioned at the superposed area; the tool 3 is rotated with a load added to it to the extent that no buckling is caused in the shapes 1, 2; and welding is performed by using a plastic flow generated by frictional heat from the rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for welding a structure made of an aluminum alloy, for example, a structure such as a vehicle, an automobile, a ship, aviation, an elevator, a pressure vessel, and a pipe, and a welding joint for welding. Regarding the structure.

[0002]

2. Description of the Related Art As a conventional friction welding method, there is a method in which workpieces are rotated and welded by frictional heat between the workpieces. On the other hand, for example, Japanese Unexamined Patent Publication No. 7-505090 discloses that a tool made of a material substantially harder than a workpiece is inserted into a welded portion of the workpiece, and the inserted tool is moved while rotating. A welding method that performs welding in the direction of the welding line, that is,
A welding method is disclosed in which friction welding is performed using plastic flow due to frictional heat generated between a rotating tool and a workpiece.
According to this method, the welding member can be joined by rotating and moving the tool with the welding member fixed with respect to the conventional friction welding method, so that even a member that is substantially infinitely long in the welding direction can be used. It is possible to carry out solid phase bonding continuously in the longitudinal direction. In this case, solid-state welding utilizing the plastic flow of metal due to frictional heat between the rotating tool and the welding member has the characteristic that welding can be performed without melting the welded part. And there are many advantages such as fewer defects because the joint is not melted.

[0003]

SUMMARY OF THE INVENTION
When the welding method described in Japanese Patent Application Laid-Open No. 505090 is applied to welding of an extruded material having a hollow inside or a honeycomb panel, there are the following problems.

That is, in this known friction welding method,
500-1000 locally on the workpiece during the welding process
kg load is applied. For this reason, the workpiece may be deformed or buckled by the load of the tool during welding, and the welding structure, shape, dimensions, and the like are limited. In particular, in the case of hollow members such as extruded members and honeycomb panels having a hollow structure in the vicinity of the welded portion, deformation tends to occur due to local compressive load, and for such hollow members such as extruded members and honeycomb panels, It was difficult to weld by such a friction welding method.

Conventionally, such extruded members and honeycomb panels are generally applied by fusion welding such as arc welding. In the case of fusion welding such as arc welding, almost no load is applied to the welding material, so that the welding structure is also lightweight. However, as described above, in fusion welding, there are problems such as large deformation after joining and many defects at joints. To prevent such problems, friction welding has attracted attention. However, when the friction welding method is applied to a welded joint structure applied to the arc welding method, deformation or buckling occurs in a workpiece, and as a result, desired welding cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made in view of such a background, and a first object of the present invention is to provide a hollow member such as an extruded member or a honeycomb panel without causing deformation of a workpiece or welding defects. It is to propose a friction welding method capable of friction welding.

A second object of the present invention is to propose a welded joint structure capable of performing friction welding without causing deformation of a workpiece and welding defects on the hollow member.

[0008]

In order to achieve the first object, the first means is to provide a welding tool comprising a metal rod formed of a material substantially harder than the material of the workpiece. In a friction welding method in which two workpieces are continuously welded in a welding line direction by generating frictional heat by being inserted into a welding portion and rotating and moving the workpiece, an end of one workpiece and the other workpiece. Are arranged so that the ends thereof overlap each other, and the welding tool is positioned at a portion where the two ends overlap, and a load is applied to the welding tool such that the workpiece does not buckle. The welding is performed by rotating the welding tool.

In this case, the workpiece can be applied to an extruded material having a hollow portion therein or a honeycomb panel. At this time, the welding tool is preferably inserted into a portion where the extruded shape member or a column member arranged at right angles to the face plate of the honeycomb panel is arranged, and welding is performed at the portion. In this case, the welding is performed in a state where one of the column members is located on the extension of the insertion portion of the welding tool into the workpiece. The interval between the two pillars is formed smaller than the outer diameter of the welding tool,
It is preferable that a load is applied to both pillar members. Also,
It is advantageous from the viewpoint of preventing defects if the two grooves provided at the overlapping portion of the ends are formed substantially parallel to each other and inclined at 10 to 60 degrees with respect to the surface of the welded portion.

In order to achieve the second object, the second means comprises a welding tool consisting of a metal rod formed of a material substantially harder than the material of the workpiece, and a welding tool comprising an overlapped welding at the end of the workpiece. Insert into the part and move while rotating 2
In a welded joint structure used for friction welding in which two workpieces are continuously welded in a welding line direction, the workpiece is formed of an extruded shape member or a honeycomb panel having a hollow portion therein, and at least one of the overlapped portions is provided. Is characterized in that a column material for supporting the welded portion is provided at the end of the column.

[0011] In this case, it is preferable that the column material is provided at least on the workpiece side inside the overlapped portion. Also,
The column material is located on an extension of the insertion portion of the welding tool. Further, the column material is provided on both of the paired workpieces, and a distance between the two column materials is set to a dimension equal to or less than a maximum diameter of the welding tool. The distance from the tip of the welding tool inserted into the welded portion to the end of the closest work piece is at least 1/1 / the diameter of the tip of the inserted welding tool.
Preferably, the length of the overlapped portion is set to 3 or more, and the length of the overlapped portion is set to be at least 1 mm larger than the end of the welding tool when the welding tool is inserted. Similarly, the length of the overlapped portion may be set to be at least 1 mm larger than the end of the welded portion when welding is completed. Further, it is desirable that the distance from the tip of the welded portion to the end of the closest workpiece be set to at least 1/3 or more of the welding width. In addition, it is preferable to provide a protruding portion that protrudes by a predetermined amount from the workpiece surface of the non-welded portion at a portion corresponding to a location where the welding tool contacts the surface of the workpiece at the welding portion. The protruding height of this protruding portion is desirably 0.5 mm or more and 3 mm or less.

On the other hand, as described above, transport equipment such as railway vehicles, aircrafts, and automobiles is required to have an increasingly lightweight structure. Therefore, it is desirable that the dimensions, particularly the thickness, of the structure be as small as possible.

However, in the friction welding method, since a load of 500 kg to 2000 kg is applied to the rotating tool during welding, deformation and buckling tend to occur particularly when the thickness of the structure near the welded portion is small. . Conversely, if the thickness near the weld is large, the weight of the transport equipment increases, which is not desirable.

Therefore, it is desirable that the size of the rotary tool for welding is as small as possible. However, if it is too small, the allowable range of welding is narrowed, and welding defects are likely to occur. For this reason, the rotating tool needs to have a size suitable for the thickness and the shape of the weldment.

Further, it is necessary to reduce the size of the welded article to the size of the rotating tool and to reduce the weight as much as possible.

Further, the welding tool comprises a large-diameter shoulder portion and a small-diameter tool tip projecting from the tip of the shoulder portion, and the tool corresponding to the shoulder diameter D and the tool tip diameter d of the welding tool. The minimum distance from the tip to the workpiece surface is X, the overlap length of the overlapped portion is Y, the thickness of the end located inside the overlapped portion is H,
When the thickness of the column material is T and the thickness of the end located outside the overlapped portion is S, D = 8 to 30 mm d = 4 to 10 mm X = 2 to 5 mm Y = 1 to 10 mm H = 1 to 5 mm T = 1 to 5 mm S = 2 to 5 mm, or A is the width near the surface of the welded portion, B is the width of the center of the welded portion, and the minimum is the distance from the tip of the welded portion to the workpiece surface. When the distance is X, the overlapping length of the overlapped portion of the workpiece is Y, the thickness of the end located inside the overlapped portion is H, and the thickness of the column material is T, A = 8 to 30 mm B = 4 to 10 mm X = 2 to 5 mm Y = 1 to 10 mm H = 1 to 5 mm T = 1 to 5 mm

Further, in order to achieve the second object,
The third means is that, in the case of a welded joint structure based on the same premise as the second means, when the workpiece is made of a plate-like extruded shape, a groove is formed in the overlapped plate material portion, and both grooves are substantially parallel. In addition, the surface is inclined by 10 to 60 degrees with respect to the surface of the welded portion.

The welding method and the welded joint structure can be applied to a structure made of an aluminum alloy, and there are great merits when applied.

Further, as an aluminum alloy suitable for the friction welding method, an aluminum alloy having the following composition is preferably subjected to a solution treatment and then an age hardening treatment.

Si: 0.2-0.9 wt%, Mg: 0.4
-1.2 wt%, Mn: 0.1-0.8 wt%, Fe: 0.
2 to 0.7 wt%, Cu: 0.1 to 0.4 wt%, Cr:
0.1-0.4 wt%, Zn: 0.25 wt%, Ti: 0.
1 wt%, balance: Al In other words, the material heat-treated with the above composition is easily mechanically deformed despite its high mechanical strength, and is suitable for the friction welding.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

<First Embodiment> This embodiment is an example in which a part of a side outer panel for a high-speed vehicle is welded by a friction welding method. FIG. This shows the state of friction welding. In this friction welding method, the side outer plate 1 and the side outer plate 2 are welded by moving a metal rod (welding tool—hereinafter, simply referred to as “tool”) 3 in a welding line direction while rotating. Since this welding method does not melt the welding material, welding can be performed simultaneously from both front and back surfaces as shown in FIG. Details of the welding at this time are shown in FIGS.

FIG. 2 is an enlarged sectional view of a part near the welded portion in FIG. As shown in the figure, the side outer plates 1 and 2 for a high-speed vehicle are extruded members (hereinafter simply referred to as “extruded members”) having a hollow inside manufactured by extrusion. These extrusion members 1 and 2 are made of an aluminum alloy, and have first and second face plates 4 and 4, respectively.
5, column members 6, 7 provided on the first and second face plates, respectively, and slope plates 8, 9, and protruding portions 12a, 13a protruding laterally from ends 12, 13 of the face plates 4, 5 respectively.
It is composed of Each of the face plates 4 and 5 is made of two parallel plate materials, and slope plates 8 and 9 are respectively disposed in a truss-like manner in an oblique direction between the two plate materials. , 7 are provided. In this embodiment, the protrusions 12a and 13a are formed by
From the projection 13a, and the projection 12a
end 1 of the extruded profile 1 so as to lie parallel to the inside of
2 protrudes in parallel to the face plate 4. Symbol 3 is
In FIG. 2, the face plate 4,
5 shows the relative positional relationship between the tool 3 and the face plates 4 and 5 when welding is performed from both sides, and FIG. 3 shows the welded portion in FIG. 2 in an enlarged manner.

In these figures, the tool 3 has a convex shape and comprises a thick shoulder 3a and a thin tool tip 3b, and the diameter D of the shoulder 3a (hereinafter also referred to as "shoulder diameter") is the tool tip 3b. (Hereinafter, also referred to as "tool tip diameter") is formed in a stepped column shape that is at least 2-3 times thicker than d, and is a welding material (workpiece).
It is made of a material that is substantially harder. Here, JIS standard SKD-61 for tool steel is used. A normal M screw 3c is provided at the tool tip 3b.
It is necessary to select optimum values for the tool tip diameter d, the shoulder diameter D, and the length L of the tool tip 3b depending on the material, structure, thickness, and the like of the welding material. In this embodiment, the shoulder diameter D is 15 mm, the tip diameter d is 6 mm, the rotation speed of the tool 3 is 1500 rpm, and the welding speed is 500 mm / min.

The center 10 of the tool 3 is disposed right above the welding groove 14 of the first face plate 4 and the welding groove 15 of the second face plate 4, particularly, substantially at the center 11 of the column 6. . That is, they are arranged so that welding is performed at substantially the center 11 of one of the column members 6 of the extruded mold members 1 and 2. this is,
This is because a downward load is applied to the tool during welding, and this load is received by the column 6. In this case, it is sufficient that at least the extension (longitudinal direction) of the tool tip 3b overlaps the plate 6.

The welding is performed by extruding the mold members 1 and 2 from the state shown in FIG.
, The center 11 of the welding grooves 14 and 15
This is carried out by applying a load to the friction welding tool 3 while rotating it and inserting it in the welding direction. That is, the workpiece is welded by utilizing the plastic flow of the metal caused by frictional heat generated between the tool 3 and the workpiece by the rotation. This will be described in more detail. As shown in FIG. 3, the welding of the extruded molds 1 and 2 is performed by the protrusion 12a of the end 12 of the one extruded mold 1 and the protrusion 13 of the end 13 of the other extruded mold 2 as shown in FIG. Into the inside of the portion 13a, the two protrusions 12a, 13
a are arranged so as to overlap each other. Here, the structure is such that the end 12 of one extrusion 1 supports the end 13 of the other extrusion 2. With such a structure, even when the gap between the welding grooves 14 and 15 is widened, the weld metal that has flowed plastically is not extruded.
The protruding portions 12a and 13a of the end portions 12 and 13 are blocked by the overlapping portion 16. With this, groove 1 which can be welded
The tolerance of the gaps of 4, 15 is increased, and the reliability of welding is improved.

On the other hand, a part of the welded portion of the extruded mold members 1 and 2 (the face plate portion of the end portions 12 and 13) is locally high (F) as can be seen from FIG. This is to prevent a part of the welded portion from being cut by the tool 3 and causing a surface dent after welding. If a dent is formed in the welded portion, it is not desirable due to mechanical strength and aesthetic appearance. Therefore, a portion of the welded portion is made to be high in advance so as to be equal to the surrounding height after welding. When the height F is 0.5 mm or less, the effect is small,
On the other hand, if it is not less than mm, the height after welding will be high. Therefore, the height F is desirably set to 0.5 mm or more and 3 mm or less. Also, this part is tool 3 as described above.
Therefore, it is desirable that the width (diameter) W of the higher portion be set to a size equivalent to the shoulder diameter D of the tool 3.

The tool tip 3b is inserted to a position slightly deeper than the overlapping portion 16 of the protrusions 12a and 13a of the extrusions 1 and 2. In addition, a downward load is applied to the welded portion by the tool 3 in the drawing. This load is tool 3
In the range corresponding to the end face of the shoulder portion 3a, and increases substantially in proportion to the size of the shoulder diameter D. Specifically, when the shoulder diameter D is 10 mm, about 500 kg, 20
In the case of mm, a load of about 1000 kg is applied. Therefore, when the strength in the vicinity of the welded portion is low, this load causes elastic deformation or plastic deformation in the welded portion and in the vicinity thereof, making welding difficult. Further, when the deformation is large, a defect occurs in the welded portion. Even when no defect occurs, the deformation causes problems in reliability and aesthetics of the whole vehicle. Therefore, in particular, when welding an extruded member having a hollow inside near the welded portion, it is desirable that the shoulder diameter D of the tool be as small as possible from the viewpoint of the load by the tool 3.

On the other hand, when this friction welding method is applied to a large structure such as a vehicle, the welding length is at least 5 m or more. In this case, maximum 3mm due to thermal deformation during welding
A slight gap (gap) occurs. For this reason, when the tool tip diameter d is small, it is impossible to cope with the opening of the groove, which causes a defect in the welded portion. Therefore, in order to obtain sound welding even when the groove is widened, it is desirable that the tool tip diameter d be as large as possible. That is, it is necessary to select the tool tip diameter d in consideration of both the load on the welded portion by the tool 3 and the opening of the groove in the welding process.

In the case of a vehicle, JIS which is excellent in both workability and mechanical properties among aluminum alloy materials is used as a material for manufacturing the complex extrusion members 1 and 2 as shown in FIG.
Standards A6061, A6063 or A6N01 are adopted. In particular, these materials are excellent in extrusion processability, and therefore also excellent in weldability by friction welding. However, it is easily deformed by the load of the tool 3, and it is difficult to weld an extruded material having a hollow portion in the vicinity of the welded portion from the viewpoint of deformation. Therefore, for such a material, the setting of the size and shape of the tool 3 is extremely important. In vehicles using the above materials, the tool tip diameter d is at least 4 mm, considering the opening of the groove during welding.
When the deformation due to the tool load during welding is taken into consideration from the mechanical properties of the material, the maximum value is about 8 mm. That is, the tip diameter d of the tool is preferably in the range of 4 to 8 mm. On the other hand, as described above, since the shoulder diameter D of the tool 3 is desirably about 2 to 3 times the tool tip diameter d, the shoulder diameter D of the tool 3 when friction welding an aluminum alloy material is determined by the tool tip diameter. If d is 4-8 mm as described above, then 8-30
mm.

As described above, in the friction welding method, a large load is applied to the welding material during welding. For this reason, as shown in FIG. 4, there is a case where deformation occurs due to the load of the tool 3 at the end of the shape member indicated by reference numerals 20 and 21 closest to the tool tip 3 d inserted into the welded portion. If the amount of deformation is large, a defect also occurs in the welded portion, which is a serious problem in the quality of the welded portion. Therefore, the distance between the tool tip 3b and the closest extruded die end 20, 21 is set to be at least 1/3 of the tool tip diameter d.
1 is set, and the thickness of the ends 20, 21 with respect to the tool tip 3b is secured. Specifically, as described above, when the tip diameter d of the tool 3 is set to 6 mm by taking an intermediate value of 4 to 8 mm, the distance X from the tool tip 3b is determined.
Is set to 2 mm or more and 3 mm.

Since the load on the welding material of the tool 3 increases substantially in proportion to the tool diameter as described above, the distance X from the tool tip 3b is also equal to the diameter d of the tool tip 3b.
If it increases, it is necessary to increase according to the increase. For example, if the tool tip diameter d is 8 mm, the distance X is 2.
If it is 7 mm or more and 10 mm, it is preferably 3 mm or more.

When friction welding is performed in such a dimensional relationship, the penetration depth P of the welded portion 18 is substantially the same as the length L of the tool tip 3b as shown in FIG. The width A near the surface of the welded portion 18 is equal to the shoulder diameter D of the tool 3,
The width B at the center of the welded portion 18 is substantially equal to the tool tip diameter d. Therefore, when the distance X from the tip of the welded portion to the end of the closest extruded die is small, the ends 20 and 2 of the die
1 is deformed, and when this deformation amount is large, a defect also occurs in the welded portion 18. Therefore, even when the relationship between the tool 3 and the shape of the mold is viewed from the weld 18 side, the distance X from the tip of the weld 18 to the nearest extruded mold end 20, 21 is set to 1/3 of the weld width B. It is desirable to make the above.

On the other hand, FIG. 4 shows a portion where one extruded mold 1 and the other extruded mold 2 overlap (projections 12a, 13a).
Overlap length Y is the tool tip 3 inserted in the welded part
b or at least from the end of the weld 18 shown in FIG.
Desirably, it is 1 mm or more. If it is less than 1 mm, the weld metal plastically flowed by the frictional heat between the tool 3 and the welding material is extruded from the overlapping portion 16, causing a defect in the welded portion 18.

As described above, it is desirable that the dimensions of the weld joint structure for friction welding be as large as possible from the viewpoint of preventing deformation due to the load of the tool. However, when the friction welding method is applied to a high-speed vehicle, it is desirable to reduce the weight as much as possible. From this point, it is desirable that the dimensions of the welded joint structure be as small as possible. Therefore, in this embodiment, a range in which the load of the tool 3 is applied, that is, the tool 3 is used as a friction welding joint structure for a vehicle due to the mechanical characteristics of the aluminum alloy of the JIS standard used for the high-speed vehicle described above.
Of the above-described portions corresponding to the shoulder diameter D and the tool tip diameter d, that is, the minimum distance X from the tool tip 3b to the end portions (surfaces) 20, 21 of the mold members, the projections 12a, 13
As shown also in FIG. 4, the overlap length Y of a, the thickness H of the protrusion 12a located inside, the thickness T of the column member 6, and the thickness S of the protrusion 13a located outside are shown in FIG. : 8 to 30 mm d: 4 to 10 mm X: 2 to 5 mm (X ≧ 1/3 d) Y: 1 to 10 mm H: 1 to 5 mm T: 1 to 5 mm S: 2 to 4 mm

On the other hand, the width A near the surface of the welded portion 18
As shown in FIG. 5, the dimensions of the above-described respective portions corresponding to the welded portion 18 as the width B of the center of the welded portion 18 are as follows: A: 8 to 30 mm B: 4 to 10 mm X: 2 to 5 mm (X ≧ 1 / 3B) Y: 1 to 10 mm H: 1 to 5 mm T: 1 to 5 mm In this case, the width of the column 6 is set in a range from the minimum dimension of 1 mm that withstands the load of the tool 3 and does not buckle to the maximum dimension of 5 mm considering the weight.

In this embodiment, the first and second
The pillars 6, 7 are attached to the respective ends 12, 13 of the face plates 1, 2 of FIG.
However, a column is provided only on the side of the face plate (corresponding to the first face plate in this embodiment) located inside the overlapping portion 16, and the load of the tool 3 is received only by this column. It is also possible. These are appropriately set according to the strength, dimensions, shape, and the like of the material of the workpiece.

<Second Embodiment> FIG. 6 shows the vicinity of a welded portion of friction welding according to a second embodiment. In the second embodiment, the distance K between the column members 6 and 7 of the end portions 12 and 13 of the first and second extrusion members 1 and 2 is equal to or less than the shoulder diameter D of the tool 3 in the first embodiment. , And all other components are configured in the same manner as in the first embodiment.

As described above, the distance K between the column members 6 and 7 is set by the tool 3
Since the load of the tool 3 can be received by both the column members 6 and 7 by making the shoulder diameter D or less, the deformation during welding can be reduced. For example, when the tool tip diameter d is 6 mm and the shoulder D is 20 mm, the interval K between the column members 6 and 7 is set to 15 mm. This allows
The center 10 of the tool 3 is disposed near the center 11 of the column 6 of the first extrusion 1, but the load of the tool 3 can also be received by the column 7 of the second extrusion 2. 6 receives less tool load. Therefore, the thickness dimension of the column members 6 and 7, that is, the dimension of the welded joint structure can be reduced, and in the case of a vehicle, weight reduction can be realized.

<Third Embodiment> FIG. 7 is a cross-sectional view showing the vicinity of a welded portion of friction welding according to a third embodiment, and shows a welded portion of a vehicle side outer plate. The third embodiment differs from the first and second embodiments in that the welding portion is not a hollow extruded member, but is a case in which a plate-shaped extruded member manufactured by simple extrusion is friction-welded. In addition, since each unit not particularly described has the same configuration as that of the above-described first embodiment, a duplicate description will be omitted.

In this embodiment, as shown in the first embodiment of FIG. 2, since there are no column members 6, 7 and swash plates 8, 9, deformation and buckling of the column member due to the load of the tool need to be considered. There is no. The dimensions of each part are set in the same manner as in FIGS. 4 and 5 shown in the first embodiment. In this embodiment, the surface of the welded portion facing the tool (the lower surface in FIG. 7)
Is provided with support means for receiving a tool load, so that deformation of the extruded material is not caused by the tool load.

In the third embodiment, as can be seen from FIG. 7, the welding grooves 14 and 15 are set so as to be substantially parallel and oblique to the welding surface. By making the groove beveled in this way, a defect occurs in the welded portion even when the groove is greatly opened during welding, as compared with the case where the groove is made a right angle as shown in FIGS. do not do. This groove angle θ is desirably 10 to 60 °, and in this embodiment, θ is set to 30 °.

When the groove angle is set to θ = 30 ° and the friction welding is performed under the same welding conditions as in the first embodiment in the present embodiment having the above dimensions, even if the groove is opened by 3 mm. No defects occurred in the welds.

In this embodiment, a simple plate-shaped extruded member is exemplified, but it is needless to say that the present invention can be applied to a hollow extruded member and a honeycomb panel as in the first and second embodiments. .

<Fourth Embodiment> FIG. 8 shows a friction welding apparatus according to a fourth embodiment. This embodiment is an example in which a floor plate 30 for a railway vehicle is welded from both front and back surfaces, and the floor plate 30 is made of an extruded member made of an aluminum alloy according to JIS standard A6N01. The composition of this aluminum alloy is as follows: Si: 0.4 to 0.9 wt%, Mg: 0.4 to
0.8 wt%, Mn: 0.5 wt%, Fe: 0.35 wt%,
It is preferable that age hardening treatment is performed after the solution is formed by Cr: 0.3 wt% and Cu: 0.35 wt%. One extruded die has a length of 20 m, a width of 500 m, and a thickness of 50 mm. The height of the welded portion of the extruded mold member 30 is locally about 1 mm.
Is getting higher. That is, F = 1 mm. In the friction welding, the tip 3b of the tool 3 is pushed out of the shape 30.
Is inserted into the center of the column members 6 and 7 and is moved while rotating. The rotating tool 3 is attached to a mobile robot 36 mounted on a mobile trolley 37, and moves in the welding line direction by the movement of the mobile trolley 37. The floor plate 30 is fixed by a fixing jig 38 from above and below and a fixing jig 39 from left and right. The details of the welding portion, the welding conditions, and the like are the same as those in the first embodiment, and thus the description is omitted.

FIG. 9 is a perspective view of a railway vehicle which has been welded to a vehicle by applying this embodiment. As can be seen from the figure, the side skins 101, 102, the roof shingles 103, 104,
A vehicle assembled by joining the 105 and the floor plates 106 and 107 by friction welding of the present embodiment is shown. The length of each of the welds 40 is 25 m at the maximum.

[0047]

As apparent from the above description, the present invention has the following effects.

That is, the end of one workpiece and the end of the other workpiece are arranged so as to overlap each other, and the welding tool is positioned at the portion where the two ends overlap, so that the workpiece does not buckle. Since welding is performed by rotating the welding tool in a state in which a load that does not occur is applied to the welding tool, friction welding can be performed without causing deformation or defects in the workpiece.

Since the workpiece is made of an extruded material or a honeycomb panel having a hollow portion inside, friction welding can be performed even on a lightweight structural material, and thereby, it can be applied to various structures such as vehicles. Becomes

The welding tool is inserted into the extruded member or the portion where the column material is arranged at right angles to the face plate of the honeycomb panel, and the welding is performed at that portion. Thus, even if the face plate is thin, friction welding can be performed without causing deformation or defects.

Since welding is performed at substantially the center of one of the column members, the load during friction welding can be reliably received by the column members.

Since the gap between the pillars is smaller than the outer diameter of the welding tool, both pillars can receive the load during friction welding, thereby reducing the thickness of the pillars. Even if the face plate is made thinner, friction welding can be performed without causing deformation or defects even if the face plate is thin.

A groove is formed at the overlapping portion of the ends, and the groove is formed substantially in parallel with the surface of the welded portion by 10 to 60.
Degree of inclination makes it possible to prevent occurrence of defects in the welded portion.

Since the workpiece is made of an aluminum alloy,
Lightweight and thin structural materials using an aluminum alloy can be joined by friction welding without causing deformation or defects.

Since the workpiece is made of an extruded member or a honeycomb panel having a hollow portion inside, and at least one end of the overlapped portion of the workpiece is provided with a column member for supporting the welded portion, the welded portion is provided. It is possible to provide a welded joint structure capable of friction welding without causing deformation or defects even if the face plate is thin.

Since the column material is provided at least on the side of the workpiece inside the overlapped portion, the load during friction welding can be reliably received.

Since the column is located on the extension of the insertion portion of the welding tool, the load during friction welding can be directly received by the column.

The column material is provided on both of the paired workpieces,
Since the distance between the two pillars is set to be equal to or less than the maximum diameter of the welding tool, the load at the time of friction welding can be reliably received by the pillars on both sides, and thereby the pillars have the minimum thickness. And the weight of the processed material can be further reduced.

Since the distance from the tip of the welding tool inserted into the welded portion to the end of the closest workpiece is set to at least 1/3 or more of the diameter of the inserted welding tool portion, the workpiece is removed. Friction welding can be performed without causing deformation and welding defects.

Since the size of the overlapping portion is specified as described above, the weld metal that has flowed plastically due to frictional heat between the welding tool and the work material is not extruded from the overlapping portion, and the occurrence of defects can be prevented.

The distance from the tip of the welded portion to the end of the closest workpiece is set to at least 1/3 or more of the welding width, so that deformation of the workpiece and welding defects do not occur. Friction welding becomes possible.

Since a projection projecting from the surface of the non-welded portion by a predetermined amount is provided at a portion corresponding to a position where the welding tool abuts on the surface of the workpiece at the welding portion, cutting is performed by the welding tool. Therefore, it is possible to prevent the surface from being dented after welding.

Since the dimensions of each part are specified as described above, it is possible to provide a welded joint structure which does not cause deformation of the workpiece and welding defects.

Since both grooves are substantially parallel and are provided at an angle of 10 to 60 degrees with respect to the surface of the welded portion,
It is possible to provide a welded joint structure in which defects are less likely to occur even in a plate-shaped extruded die.

Since the workpiece is made of an aluminum alloy,
It is possible to provide a welded joint structure capable of joining a lightweight and thin structural material using an aluminum alloy by friction welding without causing deformation or defects.

The composition of the aluminum alloy to be subjected to friction welding is as follows: Si: 0.2-0.9%, Ti: 0.1%, M
n: 0.1 to 0.8%, Cu: 0.1 to 0.4%, M
g: 0.4-1.2%, Cr: 0.1-0.4%, F
Since e: 0.3 to 0.7% and Zn: 0.25% are contained, and after solution heat treatment, it is subjected to age hardening heat treatment, so that it is possible to provide a welded joint structure for a high-speed vehicle made of a material suitable for friction welding. it can. Thus, it is possible to provide a railway vehicle that is lightweight and has no welding defects.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state of friction welding of a structural material for a vehicle according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a state of a mold member and a welded part of an extruded mold member according to the first embodiment.

FIG. 3 is an enlarged view showing a welded portion of FIG. 2;

FIG. 4 is a view showing a welding process in a welded portion shown in FIG. 3;

FIG. 5 is a view showing a state of a welded portion after friction welding according to FIG. 4;

FIG. 6 is a diagram showing a welding state in the second embodiment.

FIG. 7 is a diagram showing a state of an extruded die member and a welded portion in a third embodiment.

FIG. 8 is a view showing a friction welding apparatus according to a fourth embodiment.

FIG. 9 is a perspective view showing a state of a vehicle structure welded using a friction welding device according to a fourth embodiment.

[Explanation of symbols]

 1, 2 Extruded mold 3 welding tool 3a shoulder 3b tool tip 4,5 face plate 6,7 pillar 8,9 slope plate 12,13 end 12a, 13a projecting part 14,15 groove 16 overlap part 18 welding Part 20, 21 Mold material end

 ──────────────────────────────────────────────────の Continued on front page (72) Inventor Kinya Aota 794, Higashitoyoi, Katsumatsu-shi, Yamaguchi Prefecture Inside the Kasado Plant of Hitachi, Ltd. (72) Inventor Masakuni Esumi 794, Higashitoyoi, Kudamatsu-shi, Yamaguchi Prefecture Stock Company (72) Inventor Yasuo Ishimaru Kasamatsu, Yamaguchi Prefecture 794, Higashi-Toyoi, Yamagata Prefecture, Japan Inside Kasado Factory, Hitachi, Ltd.

Claims (26)

[Claims] 1. A welding tool comprising a metal rod formed of a material substantially harder than a material of a workpiece is inserted into a welded portion of the workpiece, and is moved while rotating to generate frictional heat. In a friction welding method for continuously welding two workpieces in a welding line direction, an end of one workpiece and an end of the other workpiece are arranged so as to overlap each other, and the welding tool is provided at two ends. A friction welding method characterized in that welding is performed by rotating the welding tool while applying a load to the welding tool such that the workpiece does not buckle. 2. The friction welding method according to claim 1, wherein the workpiece is one of an extruded member having a hollow portion therein and a honeycomb panel. 3. The welding tool according to claim 1, wherein the welding tool is inserted into a portion where a columnar member is arranged at right angles to the extruded shape member or a face plate of the honeycomb panel, and performs welding at the portion. 2. The friction welding method according to 2. 4. The friction welding method according to claim 3, wherein the welding is performed in a state where one of the pillars is positioned on an extension of an insertion portion of the welding tool into a workpiece. 5. The friction welding method according to claim 3, wherein an interval between the two column members is formed smaller than an outer diameter of the welding tool. 6. A groove is formed at an overlapping portion of the ends, and the grooves are substantially parallel to the surface of the welded portion.
The friction welding method according to claim 1, wherein the friction welding method is inclined at an angle of 60 degrees. 7. The friction welding method according to claim 1, wherein the workpiece is made of an aluminum alloy. 8. A welding tool consisting of a metal rod formed of a material substantially harder than the material of the workpiece is inserted into the welded portion at the end of the workpiece and moved while rotating to perform two processes. In a welded joint structure used for friction welding in which objects are continuously welded in a welding line direction, the workpiece comprises an extruded member or a honeycomb panel having a hollow portion therein, and at least one end of the overlapped portion A welded joint structure, wherein a column member for supporting a welded portion is provided at the portion. 9. The welded joint structure according to claim 8, wherein the column material is provided at least on a workpiece side inside the overlapped portion. 10. The welded joint structure according to claim 8, wherein the column material is located on an extension of an insertion portion of the welding tool. 11. The method according to claim 8, wherein the column material is provided on both of the paired workpieces, and a distance between the two column materials is set to be equal to or less than a maximum diameter of the welding tool. Welded joint structure. 12. The distance from the tip of the welding tool inserted into the welding portion to the end of the closest workpiece is set to at least 1/3 or more of the diameter of the tip of the inserted welding tool. The welded joint structure according to any one of claims 8 to 11, characterized in that: 13. The apparatus according to claim 8, wherein the length of the overlapped portion is set to be at least 1 mm larger than an end of the welding tool when the welding tool is inserted. Welded joint structure. 14. The distance from the tip of the welded weld to the end of the nearest workpiece is at least 1/3 of the weld width.
The welded joint structure according to any one of claims 8 to 11, wherein the welded joint structure is set as described above. 15. The length of the overlapped portion may be at least 1 mm from the end of the weld when welding is completed.
The welded joint structure according to claim 8, wherein the diameter is set to be larger by at least mm. 16. A non-welded portion having a projection projecting from the surface of the workpiece by a predetermined amount is provided at a portion of the surface of the workpiece at the welding portion corresponding to a location where the welding tool contacts. Any one of claims 8 to 15
The welded joint structure according to the paragraph. 17. A tool tip corresponding to the shoulder diameter D and the tool tip diameter d of the welding tool, wherein the welding tool comprises a large-diameter shoulder part and a small-diameter tool tip part protruding from the tip of the shoulder part. X is the minimum distance from the portion to the workpiece surface, Y is the overlap length of the overlapped portion, H is the thickness of the end located inside the overlapped portion, T is the thickness of the column material, and T is the thickness of the overlapped portion. When the thickness of the outer end portion is S, D = 8 to 30 mm d = 4 to 10 mm X = 2 to 5 mm Y = 1 to 10 mm H = 1 to 5 mm T = 1 to 5 mm S = 2 13. The distance is set to 5 mm.
The welded joint structure as described. 18. The width of the vicinity of the surface of the welded portion is A, the width of the center of the welded portion is B, the minimum distance from the tip of the welded portion to the surface of the workpiece is X, and the overlap length of the overlapped portion of the workpiece. Is Y, the thickness of the end located inside the portion to be overlapped is H,
When the thickness of the column material is T, A = 8 to 30 mm B = 4 to 10 mm X = 2 to 5 mm Y = 1 to 10 mm H = 1 to 5 mm T = 1 to 5 mm The welded joint structure according to claim 14, wherein 19. A welding tool comprising a metal rod formed of a material substantially harder than the material of the workpiece is inserted into the overlapped welded portion at the end of the workpiece and moved while rotating to perform two processes. In a welded joint structure used for friction welding in which objects are continuously welded in a welding line direction, the workpiece is formed of a plate-shaped extruded shape, and a groove is formed in the overlapped portion, and the grooves are formed. Is a weld joint structure characterized by being inclined approximately 10 to 60 degrees with respect to the surface of the welded portion substantially in parallel. 20. The method according to claim 8, wherein said workpiece is made of an aluminum alloy.
20. The welded joint structure according to any one of 17, 18, and 19. 21. The aluminum alloy is, by weight, Si: 0.2-0.9%, Ti: 0.1% Mn: 0.1-0.8%, Cu: 0.1-0.4. % Mg: 0.4-1.2%, Cr: 0.1-0.4% Fe: 0.3-0.7%, Zn: 0.25% The welded joint structure for a high-speed vehicle according to any one of claims 8 to 20, wherein the welded joint structure is formed. 22. A railway vehicle having the welded joint structure according to claim 21. 23. Inserting a tool made of a metal made of a material substantially harder than the material of the workpiece into a weld of the workpiece,
In a friction welding method of continuously welding two workpieces in a welding line direction by rotating and moving the tool, an end of one workpiece and an end of the other workpiece overlap each other. A friction welding method characterized by disposing and welding at a position. 24. Inserting a tool made of a metal made of a material substantially harder than the material of the workpiece into a weld of the workpiece,
In a friction welding joint structure for continuously welding two workpieces in a welding line direction by rotating and moving the tool, an end of one workpiece and an end of the other workpiece overlap each other. A joint structure for friction welding, characterized in that the joint structure has a shape arranged in an inclined state. 25. A method for friction welding an extruded profile or honeycomb panel having a hollow inside, wherein the end of one extruded profile and the end of the other extruded profile or the end of the honeycomb panel overlap each other. Along one or both ends of the extruded profile or at one or both ends of the honeycomb panel, and along a columnar material arranged in a direction perpendicular to the plate surface of the extruded profile. A friction welding method characterized by welding. 26. A joint structure for friction welding an extruded profile or honeycomb panel having a hollow inside, wherein the end of one extruded profile and the end of the other extruded profile overlap each other or the honeycomb panel has The ends are arranged so as to overlap each other, and are arranged at right angles to the plate surface of the extruded profile provided at one or both ends of the extruded profile or at one or both ends of the honeycomb panel. A joint structure for friction welding characterized by having a welding structure along a pillar material.