| 摘要 |
PROBLEM TO BE SOLVED: To provide a friction stir welding method and a friction stir welding device which suppress occurrence of a weld defective part and suitably perform friction stir welding of a bevel part, while suppressing a load applied to a rotary tool even when a thickness on the bevel part is changed.SOLUTION: A friction stir welding method includes: a first friction stir welding process of moving a first rotary tool arranged on an upper side in a thickness direction across a bevel part 6 while rotating the first rotary tool and, thereby, forming a first stir region E1 on the bevel part 6; and a second friction stir welding process of moving a second rotary tool arranged on a lower side in the thickness direction across the bevel part 6 simultaneously with the first friction stir welding process or after execution of the first friction stir welding process while rotating the second rotary tool and, thereby, forming a second stir region E2 on the bevel part 6. Therein, the first stir region E1 forms a region reaching an inner part from the upper side of the bevel part 6, the second stir region E2 forms a region reaching an inner part from the lower side of the bevel part 6, and the first stir region E1 and the second stir region E2 overlap with each other on the inner part of the bevel part 6 in the thickness direction. |
