Patent Application
20130032630
1. Technical Field
The present disclosure generally relates to friction stir welding repairing methods, and particularly, to a friction stir welding repairing method for a metallic housing.
2. Description of the Related Art
Friction stir welding is widely used to join aluminum alloy because it is simple to perform.
A metal structure of the stirred product can be uneven in consistency, since the material of the stirred portion of the product plastically flows during the friction stir welding process. After treatment, the different areas, specifically the stirred and unstirred portions of the product, may exhibit different textures. The joining portion of between the workpieces provides an unfavorable appearance. Despite product annealing, the difference in appearance of the joined portion persists. Therefore, this cannot satisfy a product with the stirred surface presented as an outer surface. Achievement of a favorable appearance in products obtained by friction stir welding remains a challenge.
Therefore, there is room for improvement within the art.
The components in the drawings are not necessarily drawn to scale, the emphasis instead placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
In step S202, the cover 102 is attached to the main body 101, thereby defining a joint line 103 therebetween. In the illustrate embodiment, the joint line 103 is defined at one side of the cover 102 and the main body 101. A predetermined welding area 104 is defined by the main body 101 and the cover 102 extending along the joint line 103. The predetermined welding area 104 is strip-shaped.
In step S203, a joining tool 200 is provided. The joining tool 200 includes a shaft shoulder 210 and a stir pin 220 extending from a friction surface 211 of the shaft shoulder 210. The stir pin 220 is aligned with the shaft shoulder 210 at the central axis in an imaginary straight line. A diameter of the stir pin 220 is smaller than that of the shaft shoulder 210. The stir pin 220 is a non-consumable stir pin utilized in the friction stir welding process, and has a cylindrical friction surface 221.
In step S204, the joining tool 200 is rotated and inserted between the main body 101 and the cover 102. In the friction stir welding process, the stir pin 220 is rotated and vertically inserted between the main body 101 and the cover 102, until the friction surface 211 of the shaft shoulder 210 extends slightly into the predetermined welding area 104. The joining tool 200 rotates at a relatively high speed, and is inserted between the main body 101 and the cover 102 at a relatively low speed. Therefore, the main body 101 and the cover 102 are plasticized and joined together by rotating the joining tool 200. For example, the joining tool 200 may rotate at a speed from about 2700 r/min to 3000 r/min, and inserts between the main body 101 and the cover 102 at a speed from about 20 mm/min to about 40 mm/min. In the illustrated embodiment, the joining tool 200 rotates at a speed of about 2800 r/min, and inserts between the main body 101 and the cover 102 at a speed of about 30 mm/min.
In step S205, the joining tool 200 rotates along the axis thereof relative to the main body 101 and the cover 102 and moves along the joint line 103. Therefore, the cylindrical friction surface 221 of the stir pin 220 rubs the main body 101 and the cover 102, and the friction surface 211 of the shaft shoulder 210 rubs the predetermined welding area 104. Thus, the joining tool 200 produces a local region of highly plasticized material such that the main body 101 and the cover 102 diffuse amongst each other. As such, the main body 101 and the cover 102 are joined. The joining tool 200 may move along the joint line 103 at a speed from about 40 mm/min to about 600 mm/min, and in the present embodiment, the joining tool 200 moves along the joint line 103 at a speed from about 100 mm/min, in which a rotation axis of the joining tool 200 deviates from a direction perpendicular to the predetermined welding area 104 at about 5 degrees or about 6 degrees.
In step S206, the joining tool 200 is drawn or taken out of the predetermined welding area 104, and then the predetermined welding area 104 is cooled to form the metallic housing 100. The predetermined welding area 104 may be cooled by water or wind, or by positioning in the air for a certain time.
After the step S206, the metallic housing 100 may generate a defective welding area 105. When the joining tool 200 is drawn out of the predetermined welding area 104, a hole is remained in the predetermined welding area 104, and may be not filled with the plasticized metal material; therefore, the defective welding area 105 is generated. In the illustrated embodiment, the defective welding area 105 is a circular hole.
In step S207, the defective welding area 105 is repaired by a friction stir welding repairing method. Referring to
In step S401 of the friction stir welding repairing method, a repairing welding tool 300 includes a main portion 301 and a stir end 3011 extending from an end of the main portion 301. A diameter of the stir end 3011 is larger than that of the defective welding area 105. In the illustrated embodiment, the main portion 301 and the stir end 3011 are cylindrical. The stir end 3011 has a cylindrical surface 3013 and a concave end surface 3015 connecting to the cylindrical surface 3011. An annular blade 3017 is formed at a connecting portion of the cylindrical surface 3013 and the concave end surface 3015. A depth of the concave end surface 3015 may be from about 0.5 mm to about 1 mm. The concave end surface 3015 may be a spherical surface.
In step S402 of the friction stir welding repairing method, the repairing welding tool 300 is rotated and inserted to a region of the predetermined welding area 104 adjacent to the defective welding area 105, in which the stir end 3011 is substantially at an angle tangent to the defective welding area 105 (see
Referring to
In step S404 of the friction stir welding repairing method, the repairing welding tool 300 is pulled out of the metallic housing 100, and then the defective welding area 105 is cooled. The defective welding area 105 may be cooled by water or wind, or be positioned in the air for a certain time.
Referring to
Because the repairing welding tool 300 is substantially cylindrical, the repairing welding tool 300 is easily manufactured and correspondingly has a relatively low manufacturing cost. In addition, in the friction stir welding repairing process, the repairing welding tool 300 only need to move across the defective welding area 105 once, therefore, the repair efficiency is improved. Furthermore, because the rotating axis of the repairing welding tool 300 deviates from the direction perpendicular to the defective welding area 105 at 5 degrees, the plasticized material can be evenly driven to flatten the defective welding area 105, and thus the metallic housing 100 can have an attractive appearance.
While the present disclosure has been described with reference to particular embodiments, the description is illustrative of the disclosure and is not to be construed as limiting the disclosure. Therefore, various modifications can be made to the embodiments by those of ordinary skill in the art without departing from the true spirit and scope of the disclosure, as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201110223577.5 | Aug 2011 | CN | national |
