JPH04210875A - Method for joining aluminum and aluminum alloy member - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[00011

[Industrial Application Field] The present invention relates to a method for joining aluminum and aluminum alloy members, and in particular, to a bracket for mounting various aluminum devices 9, such as aluminum heat exchangers for automobiles, etc. The present invention relates to a method for joining aluminum and aluminum alloy members suitable for joining aluminum parts. [0002] [Background Art] In general, aluminum heat exchangers 2 in automobiles, etc., for example, radiators and condenser bodies, are joined after assembly in most cases by brazing, but when the equipment is connected to a car body, etc. Arc welding is also used as a means of joining parts such as brackets to the equipment. In such case,
These components are made of thin materials and resistance spot welding is difficult; therefore, so-called TIG
(Tungsten Inert Ga5) Arc welding is suitable, and currently manual TIG welding or automatic TIG welding
IG welding is mainly used. That is, TIG arc welding involves welding by adding a filler metal to the base metal without melting it, so it can be made in a small radius and high quality can be obtained when welding small items, thin plates, etc. [0003] On the other hand, like TIG welding, MIG (
Metal Inert Ga5) Arc welding is
When using manual MIG welding, a certain level of skill is required to reliably weld the target position, and it is difficult to set the welding current. On the other hand, if the welding current is lowered, spatter will occur more often, and defects such as poor bead appearance and poor penetration may occur.Therefore, the current cannot be lower than the critical current. There is. For these reasons, MIG welding is not considered suitable for welding thin plate members related to heat exchangers, and has not been adopted. [0004]

[Problems to be Solved by the Invention] However, the currently adopted manual TIG welding or automatic TIG welding
Welding requires more time than Hi-IG welding, and for mass production, it is necessary to increase the number of welders and welders. It also has the disadvantage that quality may vary depending on the person. On the other hand, recently, a short-circuit MIGi connection method for thin plates has been proposed, and according to this method, the electrode wire can be φ0. 6-1.
2 mm is used, and the welding current range is 20 to 150
Applicable to thin plates of 3mm or less in ampere. However, with this method, when the welding time is shortened, the penetration is shallow.
There is a problem in that poor penetration at the arc start part is likely to occur, and there is a risk that the welding will not be performed reliably. [0005]

[Object of the Invention] The present invention has been made in view of the problems of the conventional example, and its purpose is particularly to solve the problem of joining parts such as brackets for attaching to heat exchangers, etc. Aluminum and aluminum alloys that can reliably join thin plate members with a total thickness of 6 mm or less even if there is a certain difference in thickness, and can shorten welding time. An object of the present invention is to provide a method for joining members. [0006]

[Means for Solving the Problems] In the present invention, the wall thickness is 0.
When joining an aluminum or aluminum alloy member with a wall thickness of 2 mm to 4 mm to an aluminum or aluminum alloy member with a thickness of 5 mm to 1.5 mm, a welding current of 150
Plug welding is performed using the MIG arc welding method at an amperage of more than 300 amperes and a welding time of less than 0.5 seconds. This aims to achieve the above-mentioned purpose. [0007]

[Operation] According to the present invention, the wall thickness is 0. 5mm to 1.5
mm aluminum or aluminum alloy member with wall thickness 2
When joining aluminum or aluminum alloy members with a diameter of 4 mm to 4 mm, use the MIG arc welding method, use a welding current range of 150 amperes or more and 300 amperes or less, and set the welding time to an extremely short time of 0.5 seconds or less. Since the welding is performed, there will be no holes in the non-welded parts, and the weld penetration will be deep enough to ensure a reliable welding. In addition, since plug welding is performed, there is a certain degree of difference in the thickness of the two plates by appropriately setting the shape of the plug, that is, its depth, diameter, etc., depending on the thickness of the member and the diameter of the electrode wire used. Reliable joining is possible even in the case of [0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. [00091 FIG. 1 shows a thin-walled aluminum tube 1 as a non-welded member, which is a target object of the joining method according to the present invention, for example, a thin-walled tube 1 constituting a header tank portion of a parallel flow condenser, and A bracket with a ladle-shaped cross section attached to the pipe 1, for example, a bracket 2 for attaching the capacitor is shown. Further, FIG. 2 shows the AA cross section in FIG. 1. In these figures, a concave groove (groove) 3 having a circular cross section is formed approximately at the center of the upper surface of the thin-walled tube 1 of the bracket 2 . During welding, filler metal is injected into this groove 3 and solidified to form a plug. [00101 In FIG. 3, B in FIG. 1 near the groove 3 is shown.
The B-line cross section is shown enlarged. In this Figure 3,
The plate thickness t1 of the bracket 2 is set to 2 mm to 4 mm in consideration of strength and weight reduction. Plate thickness t of thin-walled tube 1
2 is 0.2 considering strength and thermal efficiency. 5mm to 1
．． It is set to 5mm. [00111 Under these preconditions, in this example,
The welding current is short-circuited M, which is an MIG welding method for thin plates.
MIG the bracket 2 to the thin-walled pipe 1 by setting the welding current to 150 to 300 amperes, which is much larger than the welding current range in the IG welding method, and setting the welding time to 0.5 seconds or less.
Join by welding method. In this case, in order to set a very short welding time of 0.5 seconds or less, a computer robot was used to set the welding time in advance and weld instantly. In this way, by setting the distance P from the bottom of the groove 3 of the bracket 2 to the inner wall surface of the thin-walled tube 1 and the diameter of the groove 3 to various values, the MIG
Plug welding was performed using the welding method. [0012] As a result, the distance P from the bottom surface of the groove 3 of the bracket 2 to the inner wall surface of the thin-walled tube 1 is 1 mm to 3 m.
m, a hole is revealed in the thin-walled pipe 1 during welding,
Moreover, it was found that the bonding was performed reliably. In addition, the diameter of the groove 3 is 1.2 as the diameter of the filler metal @pole wire.
When using a wire diameter of 2 mm, consider the wire diameter.
It was confirmed that the weld metal sufficiently penetrates to the tip (open tip) of the groove 3 during welding when it is set to 4 mm or more and 4 mm or less. [0013] As a result of comparing the time required for plug welding using the conventionally adopted manual TIG welding method, automatic TIG welding method, and the MIG welding method of the present invention under the conditions determined as described above, we found that: Attach the bracket to 4
The conventional method took nearly two minutes to join the pieces individually, but it was found that the proposed method could do it within 20 seconds. [00141 As explained above, according to this example,
This makes it possible to significantly reduce the time required to join aluminum thin plate members with a total thickness of 6 mm or less, such as when joining parts such as buttons for attaching heat exchangers etc. This enables efficient mass production without increasing the number of welders and welders. Furthermore, since plug welding is employed, it is now possible to reliably join two plate members that have a difference in plate thickness, which was conventionally considered unsuitable for MIG spot welding. [0015] In the above embodiment, the shape of the groove 3 (groove) of the bracket 2 is cylindrical, but the present invention is not limited to this. As shown in 4, it may be in a so-called grove shape. [0016]

[Effects of the Invention] As explained above, according to the present invention,
By using the MIG arc welding method and using a welding current range of 150 amperes or more and 300 amperes or less, and by setting the welding time to an extremely short time of 0.5 seconds or less, it is possible to form holes in the parts to be welded. There is no darkening, and the penetration is deep enough to ensure a secure joint. In addition, since plug welding is performed, the shape of the plug can be adjusted according to the thickness of the component and the diameter of the electrode wire used. That is, by appropriately setting the depth, diameter, etc., reliable joining is possible even when there is a certain degree of difference in thickness between the two plates. Therefore, it is possible to significantly reduce the time required to join thin aluminum plate members with a total thickness of 6 mm or less, and this makes it possible to achieve efficient mass production without increasing the number of welders and welders. It is possible to provide an unprecedented and excellent method of joining aluminum and aluminum alloy members by tightening the members.

[Brief explanation of the drawing]

FIG. 1 is a partly omitted plan view showing a thin-walled aluminum tube and an aluminum bracket attached to the tube, which are the objects of the MIG welding method of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG. 1;

3 is an enlarged view of the vicinity of the bracket groove taken along the line BB in FIG. 1; FIG.

FIG. 4 is an explanatory diagram showing another shape of the groove.

[Explanation of symbols]

1 Thin-walled tube as an aluminum member with a wall thickness of 0.5 mm to 1.5 mm 2 Bracket as an aluminum member with a wall thickness of 2 mm to 4 mm

Claims (1)

[Claims] Claim 1: An aluminum or aluminum alloy member with a wall thickness of 0.5 mm to 1.5 mm and a wall thickness of 2 mm to 4 mm.
A method for joining aluminum and aluminum alloys, characterized in that plug welding is performed by MIG arc welding at a welding current of 150 amperes or more and 300 amperes or less and a welding time of 0.5 seconds or less when joining aluminum or aluminum alloy members.