HOLDING JIG AND HOLDING JIG SET FOR DOUBLE-ACTION FRICTION STIR SPOT WELDING, DOUBLE-ACTION FRICTION STIR SPOT WELDING DEVICE, AND DOUBLE-ACTION FRICTION STIR SPOT WELDING METHOD

摘要

A double-action friction stir spot welding device (10A) or a double-action friction stir spot welding method according to the present disclosure, wherein: a pin member (11) and a cylindrical shoulder member (12) that rotates around the same axis as the pin member (11) are used as a rotation tool; and a clamp member (13) is used as a holding jig, the clamp member (13) having a cylindrical shape positioned so as to surround the outer side of the shoulder member (12), and pressing a welding object (60) from the surface (60a) thereof using a circular pressing surface (13a) at the distal end of the clamp member (13). The clamp member (13) has an inclined surface (13b) that contacts the inner-side edge of the pressing surface (13a) and inclines so that the inside diameter of the clamp member (13) decreases toward the inner side as viewed from the pressing surface (13a).