JPH07116868A - Method and device for joining metallic material - Google Patents

Abstract

PURPOSE:To easily perform a joining operation by anyone without drawing on his skill and experience by causing a current to flow through the joined surface of metallic materials to be joined, opposing each other, making a sulfur concentrated layer formed by resistance heating, and vibrating the metallic materials while applying a static pressure force. CONSTITUTION:Metallic materials 13 and 14 to be joined, are held between an electrode plate 9 and the tip 5a of a horn 5, and resistance heating is performed by causing a current to flow through the metallic materials 13 and 14 to be joined while applying a perliminary static pressure force by a pressurizing means 16. After that, the metallic materials 13 and 14 are joined by confirming the formation of a sulfur concentrated layer after decreasing a temperature, and applying an ultrasonic vibration with a desired amplitude through the horn 5 while applying a prescribed static pressure force by the pressurizing means 16. In addition, even large metallic material to be joined, which are impossible to be joined by the conventional ultrasonic joining, can be joined by increasing the static pressure force by 30 to 50%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for joining conductive metallic materials, and more particularly to a solid phase joining method and apparatus for joining the same.

[0002]

2. Description of the Related Art Conventionally, as a joining method of relatively thin metal materials, an ultrasonic joining method of applying ultrasonic vibration energy to the joining surfaces while applying static pressure in the joining surface direction of the metal materials to be joined and therefor Various devices are known.

[0003]

According to the conventionally known ultrasonic bonding, diffusion bonding is performed by cleaning the bonding surface and then applying an excessive static pressure without controlling the bonding surface to apply a vibration amplitude. Therefore, deterioration of the base material and the material to be joined is severe, especially when the material is linear, it may cause crush deformation, breakage, peeling or other undetectable potential defects. There was a problem of doing.

In addition, the conventional ultrasonic joining is performed by applying a joining pressure,
Reproducibility of vibration time, horn, knurling of anvil, etc. was difficult, and I often relied on experience and intuition.

Ultrasonic bonding is basically considered to be diffusion bonding, and the oxide layer disappears when the bonded portion is broken and viewed under a microscope. From this, it is considered that the disappearance of the oxide layer at the bonded portion is the bonding. The disappearance of the oxide layer on the surface of the metal material is obtained by heating the metal material in a weak vacuum, but at the same time, the sulfur that was included as an impurity in the metal material is biased to the surface by heating and the sulfur is concentrated. Form the layers. Therefore, if bonding is performed in this state, it is possible to bond without requiring a large amount of energy, but it is quite difficult to bond metal materials to be bonded in a weak vacuum during mass production of products. Is.

The object of the present invention is to easily conduct electricity without using a higher static pressure and a higher frequency than the conventional one, or without relying on many years of experience and intuition, and without creating a weak vacuum state. It is an object of the present invention to provide a joining method and apparatus capable of joining metallic metallic materials.

[0007]

In order to achieve the above-mentioned object, the present invention provides a method for joining metallic materials, in which the joining surfaces of the joined metallic materials to be joined are opposed to each other and a current is applied to the joined metallic materials. It is flowed to form a sulfur-enriched layer on the joint surface by resistance heating, and then vibration is given while applying static pressure in the joint surface direction of the metal material to be joined.

The present invention also provides, as a device, a vibrating and oscillating means having a vibrator that also serves as one electrode, another electrode installed so as to face the vibrator, and the vibrator and the other electrode. And a pressing means for applying a static pressure to the joint surfaces of the metal materials to be joined, which are sandwiched between and.

In any of the above cases, the means for vibrating is by ultrasonic vibration, electromagnetic vibration,
Further, cam type vibration may be considered.

[0010]

According to the present invention, the metal material to be bonded is heated by Joule heat, and the oxide layer on the bonding surface disappears to form a sulfur-enriched layer. The metal materials to be joined are easily joined even by using pressure and vibration frequency.

According to the second aspect of the invention, the metal material to be welded sandwiched between the vibrator also serving as one of the electrodes and the other electrode plate is heated by Joule heat accompanying energization, and joined by the pressurizing means. Vibration is applied by the vibrator of the ultrasonic generator while receiving pressure from the direction.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings are explanatory views for explaining one embodiment of the present invention, in which reference numeral 1 denotes an ultrasonic wave generator 2, a booster 3,
For example, the vibration oscillating means is composed of a diaphragm 4 made of silicon nitride (Si ₃ N ₄ ) excellent in thermal shock resistance, and a horn 5 also serving as one electrode. The horn 5 is a stud bolt made of silicon nitride, which is the same as the diaphragm 4. It is connected to the booster 3 via 6. Since only the vibrator may be used instead of the horn, when the vibrator is used in this specification, the term includes the horn. Reference numeral 7 denotes a reflection pole base, and another electrode plate 9 is placed on the reflection pole base 7 with an insulating plate 8 also made of silicon nitride interposed therebetween. 10 is a power transformer,
Cables 11 and 12 are connected to the horn 5 and the electrode plate 9 from the power transformer 10. Between the tip 5a provided at the tip of the horn 5 and the electrode plate 9, a pair of metal materials 13 and 14 to be bonded are installed with their bonding surfaces facing each other. A pressing body 15 is placed and abutted above the pressure receiving plate 5b provided above the tip of the horn 5, and a static pressure is applied to the pressing body 15 and the reflection pole base 7 from the joint surface direction by the pressing means 16. It is supposed to be added.

Next, a case where metal materials are actually joined using the above-mentioned apparatus will be described.

[0014]

[Example 1] Titanium is selected as a metal material to be bonded,
This is sandwiched between the electrode plate 9 and the tip 5a of the horn 5, and the pre-static pressure by the pressurizing means 16 is applied to the metal materials 13 and 14 to be joined via the electrode plate 9 and horn 5.
An electric current was passed through to cause resistance heating up to about 750 ° C. Then, the temperature was lowered to 600 ° C., and it was confirmed that the sulfur-enriched layer was formed, and while the static pressure of 20 KgF was applied by the pressurizing means 16, 20 KHz was applied via the horn 5 for 0.4 sec.
When a vibration amplitude of 50 μ was applied, they were joined, and the joining strength was about the same as the base metal strength.

This is because the titanium surface has a sulfur temperature of 40.
Utilizing the fact that when the temperature rises from 0 ° C and becomes saturated at about 700 ° C and a sulfur-enriched layer is deposited on the joint surface, its diffusion bonding temperature becomes lower than that of the oxide layer. With conventional ultrasonic bonding that does not involve resistance heating,
The same bonding material requires a diffusion bonding temperature of 750 ° C,
It was necessary to apply a static pressure of 50 KgF and a vibration amplitude of 20 KHz 60 μ for 0.8 sec.

As is clear from a comparison between the two, when the present invention is carried out, the diffusion bonding temperature, the static pressure applied to the metal material to be bonded, and the vibration are higher than those of the conventional simple ultrasonic bonding. Both frequency and vibration amplitude are low, and
It was found that the time required to apply vibration was short and the energy required for joining was small.

[0017]

[Embodiment 2] Dissimilar metal materials 13 and 14 made of aluminum and copper are sandwiched between the electrode plate 9 and the chip 5a of the horn 5, and a current is applied while applying a preliminary static pressure by the pressurizing means 16. Resistance heat was generated up to about 500 ° C. After that, the temperature of the joint surface is lowered to 400 ° C., it is confirmed that the sulfur-enriched layer is formed, and a static pressure of 10 KgF is applied by using a pressurizing means while the vibration amplitude of 20 KHz 60 μ is 0.3.
When sec was applied, the strength of the base metal was almost the same as that of the base metal after joining.

If the same joining material is to be joined by conventional ultrasonic joining, the diffusion joining temperature is 500 ° C., the static pressure is 20 KgF, and the vibration amplitude of 20 KHz 70 μ is 0.8 sec. Even if
It was found that the invention of the present application is excellent without requiring the energy required for bonding.

In both the first and second embodiments described above, there is no crushing deformation of the joined metal materials to be joined,
Both kept their original shape.

Further, as a result of carrying out the above-described present invention with various materials and modes, the inventor of the present invention can still perform the operation of the present invention even with a large material to be joined, which has been impossible with conventional ultrasonic joining. Even if the pressure is increased by 30% to 50%, joining is possible, and the same applies to low frequency vibration of vibration by a vibration oscillating means using an electromagnetic type or a cam type without using high frequency resonant vibration (steady vibration). It was found that they can be joined like.

[0021]

According to the first aspect of the present invention, since the metal materials to be joined can be joined with a weaker static pressure, vibration amplitude and vibration time than in the case of the conventional ultrasonic joining, the crushing deformation like the conventional one can be achieved. It is possible to prevent breakage, peeling, etc., and to eliminate other latent defects that cannot be detected, making it easier to join, so anyone can easily do it without relying on the intuition of skilled workers and many years of experience as in the past. It is possible to obtain an effect that the joining work can be performed.

According to the second aspect of the present invention, it is possible to provide a metal material joining apparatus having improved performance without significantly improving the conventional apparatus.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for explaining the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration oscillating means 2 Ultrasonic wave generator 3 Booster 4 Diaphragm 5 Horn (vibrator) 7 Reflective pole base 9 Electrode plate 10 Power transformer 13 Metal material to be bonded 14 Metal material to be bonded 15 Pressing body 16 Pressurizing means

Claims (8)

[Claims] 1. A sulfur-enriched layer is formed on the joint surface by causing the joint surfaces of the joint metal materials to be jointed to face each other and applying an electric current to the joint metal material for resistance heating.
Next, a method for joining metal materials, characterized in that vibration is applied while applying static pressure in the joining surface direction of the metal materials to be joined. 2. The apparatus for joining metal materials according to claim 1, wherein the vibration is ultrasonic vibration. 3. The apparatus for joining metal materials according to claim 1, wherein the vibration is electromagnetic vibration. 4. The joining apparatus for metal materials according to claim 1, wherein the vibration is cam vibration. 5. A vibrating and oscillating means having a vibrator that also serves as one electrode, another electrode placed so as to face the vibrator, and a portion sandwiched between the vibrator and the other electrode. And a pressing means for applying a static pressure to the joint surfaces of the metal materials to be joined, which are joined to each other. 6. The vibration oscillating means is an ultrasonic oscillating means,
The metal material joining apparatus according to claim 5. 7. The apparatus for joining metal materials according to claim 5, wherein the vibration oscillating means is an electronic vibration oscillating means. 8. The vibration oscillating means is a cam type oscillating means.
The metal material joining apparatus according to claim 5.