| 摘要 |
<p>A method for friction-stir-welding two hollow workpieces 1 and 2 wherein, while open end portions of the workpieces 1 and 2 are butted with each other, and an annular support member 3 is disposed so as to support the butt end portions from the inside, the workpieces 1 and 2 are joined together by friction stir welding. An annular, radially outward projection 4 is formed on the entire outer circumferential surface of the support member 3 in an intermediate region along the width of the support member 3. Support portions 5 and 6 to be fitted into corresponding end portions of the workpieces 1 and 2 for supporting the workpieces 1 and 2 from the inside are formed on the support member 3 at the corresponding opposite sides of the annular, radially outward projection 4. While the support portions 5 and 6 of the support member 3 are fitted into the workpieces 1 and 2, respectively, and end faces of the workpieces 1 and 2 abut the annular, radially outward projection, the butt end portions of the workpieces 1 and 2 and the support member 3 are subjected to friction stir welding that is performed from the outside. This method enables welding of the hollow workpieces 1 and 2 without involvement of occurrence of joint defect.</p> |
