| 摘要 |
PROBLEM TO BE SOLVED: To provide a tool for friction stir welding and a device for friction stir welding with the tool for friction stir welding capable of excellent jointing of work by generating sufficient plastic flow.SOLUTION: The tool comprises: a first surface 15 which is rotated relatively to a jointing part on axis line O under a state where the first surface contacts to the jointing part of a work, and has 0.8 μm or more and 25 μm or less of a value as calculated average roughness Ra; and a second surface 16 which is formed in a successive manner to the first surface 15, is rotated relatively to the jointing part on the axis line O under a state where the second surface contacts to the jointing part, and has a value as calculated average roughness Ra less than that of the first surface 15.SELECTED DRAWING: Figure 2 |
