JP2000015448A - Joining method of titanium and aluminum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joining method of titanium and aluminum which does not require special equipment and a special joining environment and makes joining in the atmosphere possible. SOLUTION: Prior to joining between a titanium material 1 of a base metal and an aluminum material 2, surface defatting and a blast treatment is done on a joining face of a titanium material side, a thermal spray film layer 3 of aluminum base is formed thereon, further subjected to a fusion diffusion treatment with TIG welding. The titanium material 1, which has the thermal spray film layer after the fusion diffusion treatment as a joining face, and the aluminum material 2 are butted, both are joined with using TIG welding using an aluminum filler material or brazing joing using brazing filler metal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for firmly joining titanium (including a titanium alloy) and aluminum (including an aluminum alloy), which is a dissimilar metal, by welding or brazing.

[0002]

2. Description of the Related Art Titanium-based materials, such as pure titanium and titanium alloys, form a hard and brittle intermetallic compound at the time of dissimilar material welding with other metallic materials such as iron-based materials. It is considered impossible, and a method such as explosive compression bonding or diffusion bonding is used for joining the titanium-based material and the aluminum-based material in addition to the brazing joining method.

[0003]

The high frequency brazing method and the in-furnace brazing method, which are relatively frequently used for joining a titanium material and an aluminum material, are carried out in a predetermined atmosphere gas such as argon gas or in a vacuum. In particular, the atmosphere must be sufficiently adjusted so that components such as H, O, N, and C are not absorbed during the work, and special equipment is required. Costs have to be increased as equipment costs rise.

[0004] Explosive crimping and diffusion bonding methods other than the brazing method require larger and special equipment than the brazing method, and are generally used only for bonding for special applications. It is difficult to say that the joining technique is simple.

[0005] The present invention has been made in view of the above problems, without the need for special equipment and a specific atmosphere,
It is an object of the present invention to provide a joining method that enables joining of a titanium-based material and an aluminum-based material under an air atmosphere.

[0006]

According to the first aspect of the present invention, when a titanium-based material such as pure titanium or a titanium alloy is joined to an aluminum-based material such as aluminum or an aluminum alloy, the joining of the titanium-based material is performed. Applying a thermal spraying process using an aluminum-based material as a thermal spraying material on the surface, performing a melt-diffusion process on the thermal-sprayed film layer, And then TI
G welding or brazing to join them together.

According to a second aspect of the present invention, prior to the thermal spraying process according to the first aspect of the present invention, a blast process is performed on the joint surface of the titanium-based material.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, the thermal diffusion coating of the thermal sprayed coating layer is performed by T.
It is characterized by the IG welding method.

It is desirable to perform a degreasing treatment on the joint surface before or after the blast treatment, and the thickness of the sprayed coating layer is determined so that the subsequent melt diffusion treatment is easy and the joint surface of the weld joint is formed. Considering this, 0.1-1.
A range of 0 mm is desirable.

Therefore, according to the first to third aspects of the present invention, a blasting process, a thermal spraying process, and a melt diffusion process are sequentially performed on a portion to be a joining surface of a titanium-based material under an air atmosphere, and then silver-aluminum. Brazing under air atmosphere using a brazing filler metal (Ag-Al brazing filler metal), an aluminum base brazing filler metal (pure aluminum or aluminum alloy as it is), or an aluminum-based brazing filler metal TIG welding is performed using a material by a known method. According to this method, the affinity between the aluminum-based thermal spray material melt-diffused on the joining surface of the titanium-based material serving as the base material, the welding material or the brazing material, and the aluminum-based material serving as the mating base material is extremely good. Therefore, a strong joining force can be obtained while joining different metals.

[0011]

According to the present invention, it is possible to easily realize the joining of a titanium-based material and an aluminum-based material, which are dissimilar metal materials, in the air without requiring special equipment or a special environment. is there.

[0012]

FIG. 1 is a view showing a preferred embodiment of the present invention, in which a titanium-based material (pure titanium or titanium alloy) 1 as a base material is the same as an aluminum-based material (pure aluminum or aluminum alloy). 2) is shown.

As shown in FIG. 1A, a joining surface 1a of a titanium-based material 1 serving as one base material is first subjected to surface degreasing and pickling, followed by blasting.

Next, as shown in FIG. 1B, the blasted joint surface 1a is subjected to thermal spraying using pure aluminum or an aluminum alloy as a thermal spray material to form a thermal spray coating layer 3. The film thickness of the thermal spray coating layer 3 is set to 0.1 to 0.1 in consideration of easiness of a melt diffusion process to be described later and a point that the thermal spray coating layer 3 itself becomes a welding joint surface.
Set within a range of 1 mm.

Further, as shown in FIG. 1C, a melt energy is given to the previously formed thermal sprayed coating layer 3 by a TIG welding method, and the coating layer 3 is subjected to a melt diffusion treatment. As a result, a melt diffusion layer 4 is formed at the boundary between the titanium-based material 1 as the base material and the aluminum-based thermal spray coating layer 3.

Subsequently, as shown in FIG. 3D, the titanium-based material 1 as one base material and the aluminum-based material as the other base material are formed by using the sprayed coating layer 3 after the above-mentioned melt diffusion treatment as a bonding surface. Then, TIG welding is performed by a conventional method using an aluminum-based filler material, and the base material titanium-based material 1 and the aluminum-based material 2 are welded and joined. In addition, the welding part is shown with the code 5.

Alternatively, instead of the above TIG welding, silver-
The titanium-based material 1 and the aluminum-based material 2 which are base materials are brazed and joined using an aluminum-based brazing material or an aluminum-based brazing material. Examples of the brazing material include Ag-33Al, Ag-50Al, and Ag-30Al.
-Ni or Mn, Al purging sheet or the like is suitable.

The above TIG welding or brazing is performed in the atmosphere.

The present inventor made samples by the above-described TIG welding and brazing, respectively, and measured the joining strength. As a result, it was confirmed that necessary and sufficient joining strength was obtained in each case.

[Brief description of the drawings]

FIG. 1 is a process explanatory view showing a more specific embodiment of the joining method of the present invention.

[Explanation of symbols]

 1: Titanium-based material 2: Aluminum-based material 3: Sprayed coating layer

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B23K 9/167 B23K 9/167 B 9/235 9/235 Z C23C 4/02 C23C 4/02 4/08 4/08 4/18 4/18 // B23K 103: 18 F term (reference) 4E001 AA03 BB07 CB01 CB04 DG00 DG01 QA02 4K031 AA08 AB07 BA01 CB37 CB39 FA02 FA13

Claims (3)

[Claims] When joining a titanium-based material, which is pure titanium or a titanium alloy, and an aluminum-based material, which is aluminum or an aluminum alloy, spraying is performed by using an aluminum-based material as a spraying material on a joint surface on the titanium-based material side. Applying a melt-diffusion process to the sprayed coating layer, and performing TIG welding or brazing after abutting the titanium-based material and the aluminum-based material with the sprayed coating layer after the melt-diffusion process as a bonding surface. A method for joining titanium and aluminum, comprising: joining the two. 2. The method for joining titanium and aluminum according to claim 1, wherein a blast treatment is performed on a joining surface of the titanium-based material before the thermal spraying treatment. 3. The method according to claim 1, wherein the melt diffusion treatment of the thermal spray coating layer is performed by a TIG welding method.
The method for joining titanium and aluminum according to the above.