| 摘要 |
PROBLEM TO BE SOLVED: To provide a joining method of extruded shapes which minimizes preliminary working, uses no bolt or the like, and forms a joined part having stable strength and a flat surface. SOLUTION: In the joining method, respective end surfaces 4 of a pair of extruded shapes 2, 2 having hollow parts 3, 3 are mutually abutted along the longitudinal direction, a reinforcing material 5 having a cross section analogous with the hollow parts 3 is fit extending over the respective hollow parts 3 of the both shapes 2, friction- and agitation-welding is applied to the upper walls 2a of the respective shapes 2 along the above described end surfaces 4 by a tool having a frictional pin and a surface holding part, and a joined structure 1 of the extruded shapes, which has a welded part 9 inside and in whose surface a flat welding line 8 is formed, is obtained. In the above described welding, respective upper walls 2a in the vicinity of the end surfaces 4 of the shapes 2 are heated at a high speed and solidified while agitating in a solid phase, and moreover the above described reinforcing material 5 is also served as a cooling metal. Therefore, stable joining strength is obtained and port- processing such as grinding is hardly necessitated because the surface of the above described welding line 8 is flat. |
