| CPC B29C 65/0681 (2013.01) [B29K 2101/12 (2013.01); B29K 2105/08 (2013.01)] | 14 Claims |

|
1. A friction stir spot welding method, comprising:
disposing a first member and a second member to form an overlapping part where the first member and the second member overlap each other while being at least partially in contact with each other, wherein the first member is formed of a thermoplastic resin molding mixed with a fiber material, and the second member is formed of a molding containing at least a thermoplastic resin;
disposing a tool, which is a double-acting tool for friction stir spot welding including a pin and a shoulder including a hollow part into which the pin is inserted, against the overlapping part so that a rotation axis of the tool is along an overlapping direction of the first member and the second member while rotating at least the pin around the rotation axis;
plunging the pin into the overlapping part from a first member side to perform friction stir so that extension fibers extended from the fiber material of the first member in the overlapping part remain around a plunging region of the pin while retracting the shoulder from the overlapping part in a direction of the rotation axis to release the thermoplastic resin molding overflowed by the plunging of the pin into a surrounding region of the pin by the retraction of the shoulder; and
bringing the shoulder close to the overlapping part in the direction of the rotation axis to wrap the extension fibers when the resin molding material overflowed is backfilled into the plunging region from the surrounding region while retracting the pin from the overlapping part.
|