JPS61283488A - Joining method for al and al alloy - Google Patents

Abstract

PURPOSE:To improve the quality and strength of a joint part by removing oxide films from joint surfaces and subjecting the joint surfaces to low-temp. joining with a brazing filler metal consisting of an Al-Mg-Cu alloy which contains specific wt% each of Mg and Cu and is amorphous. CONSTITUTION:The joint surfaces of Al and Al alloys are subjected to a dry etching treatment to remove the oxide films and stains of the joint surfaces. The amorphous alloy film of the brazing filler metal consisting of the Al-Mg-Cu alloy or Al-Mg-Cu-Si-Zn alloy is disposed by a sputter vapor deposition method on the cleaned joint surfaces. The brazing filler metal which contains 25-25% Mg, 3-15 Cu and the balance Al or further contains 3-5% Si and 0.5-1.0% Zn is used. The joint surfaces are subjected to the low-temp. joining at 480-520 deg.C in a vacuum or inert gaseous atmosphere. The generation of defects is thereby prevented and the quality and strength of the joint part are improved.

Description

[Detailed Description of the Invention] [Background of the Invention] Al and Al alloys have an oxide film (A/, gos) on the surface.
This makes joining difficult. For this reason, methods such as chemical treatment and mechanical polishing are used to remove the oxide film (AlOs) on the Al surface. has no effect. Tokuko Sho 57-184574,
Efforts are being made to improve this by using deoxidizers and surfactants.

Furthermore, in the brazing method, bonding is performed using flux.

Bonding of Al and Al alloys in vacuum or in an inert gas atmosphere is difficult to bond with an oxide film (k) because flux is not used.
Bonding is difficult because Lxos1 cannot be removed. Al-8i is used as a brazing filler metal for joining these nine aluminum and aluminum alloys.
-Mg-based alloy is used. Also, special public service 58-2
Al-8i-Qa alloys such as 3197 and special public Sho 5g
-10980, an AL-8i-Mg-I n-based alloy is used as a brazing material. However, when joining Al and Al alloy using the above-mentioned brazing filler metal, the joining temperature is 600°C.
Since the temperature is around C, complex and precise parts are likely to be deformed, which limits the range of use. Furthermore, there are many problems in joining Al alloys, such as the fact that the joining temperature is high enough to melt the base material, making it unusable.

[Object of the invention] The object of the present invention is to remove the oxidation degree [(Al*Ch) and enable low-temperature bonding in vacuum or in an inert gas atmosphere,
Furthermore, to provide a brazing material for joining Al and Al alloys and for joining different types of Cu and Cu alloys to Al and Al alloys, and a joining method thereof, which prevents joining defects and provides a high-quality, high-strength joint. It is in.

[Summary of the invention]

In the present invention, after removing the oxide film (ALOs) from the Al bonding surface by dry etching, the bonding surface KAl-25~354Mg-
After providing the 3-15% Cu amorphous alloy film, the bonding surfaces were made to face each other and the bonding temperature was 4 in a vacuum or an inert gas atmosphere.
This is a joining method in which joining is performed at 80 to 520C.

According to the joining method of the present invention. By performing dry etching treatment (such as Ar ion beam etching) on the bonding surface of Al and Al alloy, the degree of oxidation K (Al*Os) and deposits can be removed and a clean surface can be formed. Since the bonding surfaces of the alloy are activated, it is possible to perform bonding in a vacuum or in an inert gas atmosphere, which was previously difficult.

For these reasons, conventional pre-bonding treatments such as chemical treatment and mechanical polishing are no longer necessary. Also, bonding can be performed without using flux.

Next, after cleaning the joint surfaces of Al and Al alloy, an Al-Mg-Cu alloy film is formed by sputter deposition. It enables low-temperature joining of Al and Al alloys, yields high-quality and high-strength joints, saves energy and improves workability, and is suitable for joining precision parts that do not want to be deformed.

The brazing filler metal for Al bonding of the present invention contains 25 to 35% Mg.

Al-Mg-Cu alloy containing 3-151Cu or 2
5-351 Mg, 3-15% Cu, 3-548 i, 0
．． Al-Mg-Cu-8i containing 5-1.0% Zn
-7,n alloy, which is a low-temperature bonding brazing material in vacuum or in an inert gas atmosphere.

The brazing filler metal for joining of the present invention is an amorphous alloy, and its melting temperature is 450°C to 480°C. The advantage of using an amorphous alloy is that it can be joined at low temperatures and M
Evaporation of g is suppressed. Because the components are homogeneously dispersed, the melting of the brazing filler metal is uniform, and the reaction between the base metal and the brazing filler metal is strongly compressed, improving wettability. Since the melting temperature range of the brazing filler metal is 450t:' to 480C, the joining temperature can be set to 480C to 520C. Al and Al
Alloys can be joined at low temperatures. Furthermore, since the melting temperature range of the brazing material is 450° C. to 480° C., bonding can be performed below the Al-Cu eutectic temperature (approximately 548° C.), thereby suppressing eutectic reactions. Therefore, by using the brazing material of the present invention, dissimilar joining of Cu and Cu alloys and Al and Al alloys can be performed.

Next, we will discuss the functions of each component of the joining brazing filler metal.

Mg lowers the melting temperature of the brazing filler metal for joining, and
Reduces Os and improves the wettability of the brazing filler metal and base metal. However, if it is less than 25 degrees, no effect of lowering the melting temperature is observed, and if it is more than 35 degrees, compounds are likely to be generated and there is a risk of contaminating the inside of the furnace during bonding.

Cu lowers the melting temperature of the joining brazing material and is effective in making the brazing material amorphous. It also increases the fluidity of the brazing filler metal and improves its wettability. If it is less than 31, the effect is not recognized,
In particular, the amorphization of the brazing filler metal is damaged. If the amount exceeds 15, intermetallic compounds are likely to be formed and the joint will deteriorate.

3-51 Si was added in order to lower the melting temperature of the joining brazing material and increase the fluidity of the brazing material.

7. n is 0.5 to 1.01 to improve anticorrosion effect
Added.

The KT parts manufactured by the joining method of the present invention do not have defects such as voids and poor joining, and can have a joining strength equivalent to that of the base material. Also, even if pressure is applied during joining,
T-made parts are manufactured without deformation.

[Embodiments of the invention]

Examples of the present invention will be described below.

Example 1 Al100 material and A3052 material were used as test materials. After performing ultrasonic cleaning in acetone for about 5 minutes, dry etching treatment (Ar ion beam treatment) was performed on the joint surfaces of the test materials. Table 1 shows Ar ion beam processing conditions. The bonding surface of the Al alloy was shaved by about 200 people under the treatment conditions shown in Table 1 to remove the oxide film (Al*Ox) and deposits.

Next, the AL-Mg as a brazing material for Al bonding of the present invention was applied to the bonding surface of the ht gold alloy, which had been made clean by sputter vapor deposition.
-A Cu-based alloy film was formed. Table 2 shows sputter deposition conditions. The sputtering power was about 700 W, and the alloy film formation rate was about 0.22 μm/−. Table 3 shows the composition and properties of the brazing filler metal of the present invention. As a comparative alloy film, the Al-35% Mg eutectic alloy film (thickness: 11 μm) of A&1 is crystalline and its melting temperature is about 450C. On the other hand, as shown in Table 31C, the alloy films of A2 to A5 as brazing materials of the present invention are all amorphous films, and their melting temperature is about 455°C.
~470C. When the amorphous alloy film of the present invention reaches the melting temperature, it melts rapidly and uniformly throughout, and reacts well with the base material, improving wettability. On the other hand, in the case of an AI crystalline alloy film, the Mg in the alloy that melts gradually and partially evaporates, resulting in a problem in bondability.

An alloy film of the brazing material of the present invention was formed on the bonding surface of the Al alloy by sputtering, and bonding was performed. Table 4 shows the bonding conditions. AIloo.

A3052) was bonded at a bonding temperature of 500 C, a bonding time of 1 h, a pressing force of 0.2 K41 f/ms+'', and a vacuum [lX1O-sTOrr.
) Table 5 shows the joint strength of the Al100 joint, and Table 6 shows the joint strength of the A3052 joint. Al-35 superior Mg alloy film (A1
) The reason why the bonding rate of Al alloys (AIloo and A3052) is low is that poor bonding defects such as voids and non-bonding occur, and this is because Mg contained in the alloy film during bonding is This is due to the slow evaporation of the film during melting. On the other hand, in the A/ and alloy joints made of alloy films A2 to A5 of the present invention, good joints were obtained without occurrence of poor joint defects such as voids and non-joints. This is because the alloy film is amorphous and melts rapidly and uniformly.

As shown in Table 5, the tensile strength of the Al100 base material is approximately 10,
2 Kff /W”.Al-
The bonding rate of the bonded area using the 35% Mg alloy film (41) is 70
The bonding strength is approximately 5.3 Kif/■2, and the joint portion breaks at approximately 52 Kif of the material. On the other hand, the bonding strength of the A1100 joint using the Grave 2-&50 alloy film of the present invention is about 7.6-7.0 Klf/wa2, which is about 804 of the material strength, but all of them are base material fractures. As shown in Table 6, the joint strength of the A3052 joint is 42
~ Approximately 16.5 Kg by using the alloy film of boiling 5
f, / fl", the base material fractured at approximately 85 degrees of material strength. This is because the bonding alloy film is amorphous and melts rapidly and uniformly, resulting in a homogeneous joint with no bonding defects. As described above, by joining Al alloys using the brazing filler metal and joining method of the present invention, a high-quality, high-strength joint could be obtained.

Example 2 Different materials of kl and Cu were joined. The sample material is Al1
00 material and oxygen-free steel were used. After the sample material was ultrasonically cleaned in acetone for about 5 minutes, the joint surface of the sample material was subjected to dry etching treatment (Ar ion beam treatment).

Under the Ar ion beam processing conditions shown in Table 1, Al10
The joint surface of 0 material is approximately 20OA, and the joint surface of oxygen-free steel is approximately 4
5OA was scraped to remove the oxide film and deposits.

Next, 9Al1 is formed on the clean surface by sputter deposition method.
A kl, -Mg-Cu alloy film was entirely formed on the bonding surfaces of the 00 material and the oxygen-free copper as the brazing filler metal for bonding of the present invention. Sputter deposition was performed under the conditions shown in Table 2.

Bonding alloy films of flats 2 and 3 shown in Table 3 were used as the bonding brazing filler metal of the present invention.

The joining of dissimilar materials, Al100 material and oxygen-free steel, was performed under the conditions shown in Table 4. Table 7 shows the joint strength of the joints. A
In the dissimilar material joint between the l100 material and the oxygen-free steel, there were no defects such as voids or non-joints, and no intermetallic compounds were formed in the joint, resulting in a homogeneous and high-quality joint. Its joint strength is about 7.0~7.2 K4f/sw
”, and the Al side base material breaks at an elongation of about 60 and a reduction of about 60. As described above, the brazing filler metal and joining method of the present invention make it possible to join dissimilar materials of Al and Cu, resulting in high quality, A high-strength joint could be obtained.

〔Effect of the invention〕

According to the brazing material and bonding method of the present invention, low-temperature bonding can be performed in vacuum or in an inert gas atmosphere, and high quality is achieved without defects such as voids and poor bonding.

High-strength joints can be obtained, and complex and precise Al parts and kl/Cu composite parts can be manufactured.

By using the brazing filler metal for joining of the present invention, joining is possible without performing Ar ion beam treatment, and a high-strength joint can be obtained.

A low-temperature plating sheet can be manufactured by using KT and Al alloy as a core material and forming the joining brazing material of the present invention on the surface thereof.

Table 1 Table 2 Table 3 Table 4

Claims (4)

[Claims] 1. In the method of joining Al and Al alloys, the brazing filler metal contains 25 to 35% Mg, 3 to 15% Cu, and the balance is Al.
A method for joining Al and Al alloys, characterized by using an Al-Mg-Cu alloy consisting of: 2. In claim 1, the brazing material for joining is 25 to 35% Mg, 3 to 15% Cu, 3 to 5% Si,
Al-M containing 0.5-1.0% Zn and the balance Al
A characterized by using g-Cu-Si-Zn alloy
A method for joining L and Al alloys. 3. Claims 1 and 2, wherein the brazing filler metal is an amorphous alloy;
Alloy joining method. 4. In claims 1 and 2, after removing the oxide film (Al_2O_3) and dirt from the joint surfaces of Al and Al alloy by dry etching, an amorphous alloy film is formed on the joint surfaces by sputtering. A method for joining Al and Al alloys, which is characterized in that after they are provided, the joining surfaces are faced to each other and joined at a joining temperature of 480° C. to 520° C. in a vacuum or an inert gas atmosphere.