JPH0569120A - Method for brazing aluminum material through ultrasonic waves - Google Patents

Abstract

PURPOSE:To favorably join aluminum materials to each other and to reduce the cost. CONSTITUTION:Solder 11 is interposed on a joining surface between two aluminum materials A1, A2. The joining surfaces of both aluminum materials A1, A2 are pressed to each other by pressure loading 0.1kgf/mm<2> in the pressing direction and ultrasonic oscillation is given to at least one aluminum material A1 of them to break the oxcide film on the joining surfaces of both aluminum materials and simultaneously with this, both aluminum materials A1, A2 are joined by heating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of aluminum automobile parts such as automobile intake manifolds, aluminum heat exchangers, etc. Sonic brazing method.

In this specification, the term "aluminum" includes aluminum alloy in addition to pure aluminum.

[0003]

2. Description of the Related Art To braze an aluminum material, it is necessary to remove an oxide film formed on the surface of the joint surface. Then, conventionally, in order to remove the oxide film, brazing is performed using a flux. However, since the aluminum product after brazing corrodes due to the residue of the flux, there is a problem that the cleaning process of the flux must be performed after the brazing, which is troublesome and costly.

Therefore, as a brazing method for solving such a problem, there is known an ultrasonic soldering method in which ultrasonic waves are used to remove an oxide film on a joint surface for soldering. The first of the ultrasonic soldering methods is to immerse the aluminum material to be joined in the molten solder contained in the treatment tank, and then use the ultrasonic vibrator attached to the treatment tank to form the molten solder. This is a method of soldering while destroying the oxide film on the joint surface by applying ultrasonic vibration.

However, this method has a problem that the equipment becomes large-scaled, a large amount of solder is required, and the wall of the processing tank is corroded by ultrasonic waves, resulting in high cost. Further, in the lap joint portion, the anti-shrink joint portion, and the butt joint portion having a small clearance, there is a problem that the oxide film is not sufficiently destroyed and a joint failure occurs. In order to solve this problem, it is necessary to increase the clearance of the joint, but this does not provide sufficient dimensional accuracy of the product obtained, and in some cases there is a problem that the aluminum materials will be displaced during the joining process. ..

The second ultrasonic soldering method is a soldering method using a soldering iron to which an ultrasonic vibrator is attached.

However, this method has a problem that the life of the tip of the soldering iron is short and the cost is high.

An object of the present invention is to provide a method for ultrasonic brazing of aluminum material which solves the above problems.

[0009]

In the ultrasonic brazing method for aluminum materials according to the present invention, a solder is interposed between the joining surfaces of two aluminum materials so that both aluminum materials can be welded to each other.
While pressing the joining surfaces with a pressing force of 1 kgf / mm ² or less, ultrasonic vibration is applied to at least one of the aluminum materials to destroy the oxide film on the joining surfaces of both aluminum materials. It is characterized in that both aluminum materials are joined by heating at the same time.

In the above description, it is preferable to use, for example, pure Zn or a Zn-Al alloy as the solder, but the solder is not limited to these.

The pressing force applied to pressurize the two aluminum materials is limited to 0.1 kgf / mm ² or less because buckling or material deformation may occur if the pressure is exceeded.

The heating is preferably performed using a high frequency induction heating device, but the heating is not limited to this.

[0013]

Function: A solder is interposed between the joining surfaces of two aluminum materials, and both aluminum materials are pressed with a pressing force of 0.1 kgf / mm ² or less in the direction of pressing the joining surfaces, and at least one of the aluminum materials is pressed. When ultrasonic vibration is applied to the aluminum oxide material to destroy the oxide film on the joint surface of both aluminum materials and at the same time, the molten solder flows between the destroyed oxide films and reaches the base material of the joint surface. Therefore, it becomes possible to satisfactorily bond the aluminum materials.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an apparatus used for joining round bar-shaped aluminum materials with a butt joint according to the method of the present invention. In the following description, FIG.
The left and right of is called left and right.

In FIG. 1, the ultrasonic brazing device comprises a fixed base (2) fixedly provided on a base (1) and a fixed base (2).
And a holder (3) movably provided in the left-right direction and holding one round bar-shaped aluminum material (A1).
On the right side of the holder (3), a bracket (4) protruding upward is fixedly provided on the fixing base (2), and the bracket (4) has an upper end facing in a direction orthogonal to the left-right direction. A pressure lever (5) is mounted that is rotatable around a horizontal axis. The upper end of the weight suspension member (7) is pivotally attached to the right end of the holder (3). A load weight (8) is detachably attached to the weight suspension member (7).
By changing the weight of (8), the pressure applied to the joining surfaces of the two aluminum materials (A1) and (A2) described later is changed.

On the left side of the fixed base (2), a horn (9) for increasing the vibration speed of ultrasonic waves transmitted by an ultrasonic vibrator (not shown) is arranged at a distance from the fixed base. At the lower end of the horn (9), hold the other aluminum material (A2)
0) is provided, and the holding portion (10) holds the other aluminum material (A2) so as to be on the same axis as the one aluminum material (A1). Both aluminum materials (A1)
A solder (11) is interposed between the joint surfaces at the tip of (A2). Further, an induction coil (12) of a high-frequency induction heating device having a predetermined length in the left-right direction is arranged at the abutting portion between the tips of the two aluminum materials (A1) and (A2).

In such a structure, in order to braze both aluminum materials (A1) and (A2), both aluminum materials (A1) and (A2) are pressed by the load weight (8) through the pressure lever (5). )
0.1kgf in the direction to press the joint surfaces of
While pressing with a pressing force of / mm ² or less, the ultrasonic vibration transmitted from the ultrasonic vibrator is applied to the aluminum material (A2) on the left side by the horn (9). At the same time,
High frequency heating is performed by the induction coil of the high frequency induction heating device. Then, by ultrasonic waves, both aluminum materials (A1) (A2)
The oxide film on the joint surface is destroyed, and the molten solder reaches the base of the joint surface between the destroyed oxide films, and as a result, both aluminum materials (A1) and (A2) are well joined.

A more specific embodiment of the method of the present invention will be described below.

This specific example was carried out using the apparatus shown in FIG. Two round rod-shaped aluminum materials (A1) and (A2) made of JIS A1050 with a diameter of 5 mm, a length of 30 mm and a diameter of 5 mm and a length of 50 mm are prepared. After performing the polishing treatment, an ultrasonic cleaning treatment was performed using acetone. The center line surface roughness of the joint surface is 19 μm. Further, as the solder (11), a disk-shaped one made of pure Zn and having a diameter of 5 mm and a thickness of 0.2 mm was prepared. Then, the first aluminum material (A1) was held by the holder (3) and the second aluminum material (A2) was held by the holding portion (10) of the horn (9).

In this state, the load weight (8) applies a pressure of 0.127 MPa in the direction in which the joining surfaces of the aluminum materials (A1) and (A2) are pressed against each other via the pressure lever (5). While pressurizing, high frequency heating was performed by the induction coil (12) of the high frequency induction heating device so that the heating and cooling conditions shown in FIG. 2 were obtained. Then, when 5 seconds passed from the start of heating, ultrasonic vibration emitted from the ultrasonic vibrator was applied to the left aluminum material (A2) by the horn (5) for 5 seconds. Output power of ultrasonic wave is 500W, frequency is 19kHz
z and amplitude were 23 μm. In this way, both aluminum materials (A1) and (A2) were joined.

When a tensile test was conducted using the obtained jointed product, the aluminum member was not fractured at the jointed portion, so-called base metal fractured.

[0023]

According to the ultrasonic brazing method for aluminum materials of the present invention, the aluminum materials are satisfactorily joined as described above. Moreover, unlike the conventional first ultrasonic soldering method, large-scale equipment and a large amount of solder are not required, and since ultrasonic waves are applied only to the aluminum material, there is no fear that the device will be destroyed. Absent. Therefore, the cost is lower than that of the conventional first method. Further, unlike the second conventional ultrasonic soldering method, since a chip having a short life is not required, the cost is lower than that of the second conventional method.

[Brief description of drawings]

FIG. 1 is a view showing an apparatus used for joining round bar-shaped aluminum materials with a butt joint according to the method of the present invention.

FIG. 2 is a diagram showing heating / cooling conditions in a specific example.

[Explanation of symbols]

 11 Solder A1 Aluminum material A2 Aluminum material

Claims (1)

[Claims] 1. A solder is interposed between the joining surfaces of two aluminum materials so that both aluminum materials are 0.1 kgf / mm.
Pressurize the joint surfaces with a pressing force of ² or less and apply ultrasonic vibration to at least one of the aluminum materials to destroy the oxide film on the joint surface of both aluminum materials and heat at the same time. A method for ultrasonic brazing of aluminum materials, characterized in that both aluminum materials are joined together.