JPH07227618A - Al alloy extrudate having excellent bending workability - Google Patents

Abstract

PURPOSE:To provide an Al alloy extrudate having excellent bending workability in the case bending and more particularly working of the Al alloy extrudate having a hollow sectional shape is severe and in the case the extrudate is worked to intricate shapes. CONSTITUTION:This Al alloy extrudate hating the excellent workability is formed by providing the Al alloy extrudate formed to the hollow sectional shape by welding and joining of plural pieces of members with welded parts in positions exclusive of corner part. The Al alloy extrudate formed to the hollow sectional shape having middle ribs is provided with the welded parts in the positions exclusive of the corner parts and the positions exclusive of the intersected parts of the middle ribs and a flange or web. An effect is higher if the welding area is increased by forming the welded parts in a direction where the groove joint direction of the welded parts is not parallel with the thickness direction of the members to be welded. The Al alloy extrudate is particularly effective for the intricate shapes where bending of automotive parts and building members is difficult.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum alloy extruded material having a welded portion and having a hollow cross section, and is particularly effective for automobile parts and building members where bending is difficult or for complicated shapes. The present invention relates to an Al alloy extruded material having excellent bending workability against cracking during bending by a bending machine.

[0002]

2. Description of the Related Art Conventionally, Al having various sectional shapes has been used for automobile parts and building members.
Alloy extruded material is used. Among them, an Al alloy extruded product having a hollow cross-sectional shape is manufactured by welding a plurality of Al alloy members.

A having such a hollow cross section and a welded portion
l When bending an extruded alloy material, if a bending radius smaller than a normal bending radius is required, distortion and deformation on the outside of the bending increase. Therefore, in order to secure the elongation of the material that can prevent the occurrence of cracks during bending, Al alloy materials such as T1 material and T4 material that have not been artificially aged have been used.

However, from the viewpoint of productivity and cost, when it is necessary to use T5 material or T6 material whose strength has been increased by heat treatment, when the processing conditions are more severe, or when processing into a complicated shape. As a result of deformation such as wrinkles and dents on the outside of bending, a large tensile force was applied to the corner portion and the flat surface portion, and cracks occurred in the welded portion during bending.

Under the above circumstances, the present invention is excellent in bending workability of an Al alloy extruded material having a hollow cross-section, particularly when it is difficult to process or when it is processed into a complicated shape.
It is intended to provide an alloy extruded material.

[0006]

In order to solve the above-mentioned problems, the inventors of the present invention have conducted extensive studies on an Al alloy extruded material having excellent bending workability, and as a result, increased the position of the welded portion and the welded area of the extruded material. It has been found that the above problems can be solved by doing so.

That is, according to the present invention, in an Al alloy extruded material in which a plurality of members are welded and joined into a hollow cross-section, a welded portion is provided at a position other than a corner portion. The main point is the extruded Al alloy material.

Another aspect of the present invention is an Al alloy extruded material in which a plurality of members are welded and joined to each other to form a hollow cross section having a middle rib, except for a corner portion and a crossing portion of the middle rib and the flange or the web. The gist is an Al alloy extruded material excellent in bending workability, which is characterized in that a welded portion is provided at a position.

Furthermore, another aspect of the present invention is characterized in that, in the above Al alloy extruded material, the groove joint direction of the welded portion is formed in a direction not parallel to the thickness direction of the member to be welded, and the welded area is increased. I am trying.

[0010]

The present invention will be described in more detail below.

When an Al alloy extruded material having a hollow cross-section having a welded portion is bent, as shown in FIG. 1, it is deformed to the inside of the profile in the bending radius direction and outside of the profile in the direction orthogonal to the bending radius. Deformation that bulges inward occurs. Since such deformation occurs, it is necessary for the corner portion not only to extend in the extruding direction of the profile during bending, but also to extend in the direction orthogonal thereto. Especially when there is a welded part at the corner,
There is not enough strength and cracks occur.

Similarly, in an Al alloy extruded material having a cross-section having a middle rib, not only when there is a welded portion at the corner, but also when there is a welded portion at the intersection of the middle rib and the flange or the web. Cracks occur at the part.

Therefore, in the present invention, the welded portion is located at a position other than the corner portion, or when the intermediate rib is provided, at a position other than the intersection of the intermediate rib and the flange or the web.

The positions of the welded portions are positions other than the corners,
Alternatively, in the case of having a middle rib, a welded portion can be provided at an appropriate position at a position other than the intersection of the middle rib and the flange or the web, but preferably a corner portion or the intersection of the middle rib and the flange or the web. It is recommended to provide the welded part as far away from the part as possible.

Further, in the present invention, in addition to providing the welded portion as described above, it is preferable that the welded joint angle is set so as to increase the welded area in order to increase the strength of the welded portion. That is, by forming the groove joint direction of the welded portion in a direction that is not parallel to the thickness direction of the welded member, it is possible to increase the welded area as compared with the case where it is formed parallel to the thickness direction of the welded member. As a result, the strength of the welded portion is increased. This angle is
Desirably 20 to 40 with respect to the thick surface of the member to be welded
And more preferably 30 °.

In order to manufacture an Al alloy extruded material having a hollow cross section by welding, Al alloy members having various shapes such as a flat plate shape, an L shape and a T shape can be used. Well-known welding methods such as TIG welding and MIG welding can be used as the welding method. Needless to say, the Al alloy material can also be used with various component systems and compositions. As a matter of course, a typical extruded Al alloy No. 6000 series (Al-
Mg-Si system) (eg, 6N01, 6063, etc.), 7000
A number system (Al-Zn-Mg system) (eg, 7003, etc.) is also included.

Particularly, it is effective for a tempered material having an increased strength which is artificially aged such as T5 and T7. For Al alloy extruded materials with such high strength, the maximum bending radius is 1
It can be improved by 0% or more.

Next, examples of the present invention will be described in comparison with comparative examples.

[0019]

[Example 1]

6NO1 (T5) and 6N0 as Al alloys
1 (T1) using multiple members, 2 types with different welding position and 1 type with larger welding area
The types were manufactured by welding so as to have the cross-sectional shapes and dimensions shown in FIG. 2, and the bending workability was evaluated by the limit bending radius with a multi-bender.

[0021] Tensile strength σв test material (plate material), the yield strength sigma _{0. 2,} and the breaking elongation δ was measured according to the metal material test method defined in JIS standard. The results are shown in Table 1.

FIG. 3 is a schematic diagram showing a bending test method. The bending workability was evaluated by the presence or absence of cracks in the processing under the bending conditions shown in Tables 2 and 3. The results are also shown in Tables 2 and 3. As is clear from this table, in the examples of the present invention, both 6N01 (T5) and 6N01 (T1) had better bendability than the comparative examples. In particular, in the examples of the present invention in which the welded area was large, no crack was observed even with a small limit bending radius.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

Example 2

The present example is an example of an Al alloy extruded material having a shape having a middle rib shown in FIG. An Al alloy extruded material was manufactured in the same manner as in Example 1 except that the cross section had a shape with a middle rib, and the bending workability was evaluated by the presence or absence of cracks in the processing under the bending conditions shown in Table 4. The results are also shown in Table 4. As is clear from this table, the inventive examples had better bending workability than the comparative examples.

[0028]

[Table 4]

Similar results were obtained for extruded materials made of Al alloys having a component system or composition other than the above examples.

[0030]

As described above, the aluminum alloy extruded material of the present invention can prevent the occurrence of cracks from the welded portion even if it is subjected to severe bending, and is a shaped material using a tempered material having high strength. It is also suitable for automobile parts and building members because it can be applied to and is excellent in bending workability.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a deformation state of an extruded shape member during bending.

2 (1), (2), and (3) are views showing the cross-sectional shape and dimensions of the test material and the position of the welded portion, respectively.

FIG. 3 is a diagram illustrating an outline of a multi-bender and a procedure of a bending test.

4 (1) and (2) are views showing the cross-sectional shape and dimensions of the test material and the position of the welded portion, respectively.

Claims (5)

[Claims] 1. An Al alloy extruded material having a hollow cross-section formed by welding and joining a plurality of members, wherein a welded portion is provided at a position other than a corner portion, which is excellent in bending workability. Alloy extruded material. 2. An Al alloy extruded material having a hollow cross-section having a middle rib formed by welding and joining a plurality of members, and is welded to a position other than a corner portion and a position other than the intersection of the middle rib and the flange or the web. Al alloy extruded material with excellent bending workability, which is characterized by the provision of a section. 3. The Al alloy extruded material according to claim 1, wherein the groove joint direction of the welded portion is formed in a direction that is not parallel to the thickness direction of the member to be welded to increase the welded area. 4. The Al alloy extruded profile according to claim 1, 2 or 3, wherein the Al alloy material is a material subjected to artificial aging treatment. 5. The Al extruded material is applied to a bending process for improving a limit bending radius by 10% or more.
The Al alloy extruded material according to 2, 3 or 4.