Abstract: A method includes the following: an incidence step in which ultrasonic waves from an insertion side and the side opposite thereto of a tool are caused to be incident on a joint part when a workpiece is joined by the tool that has a probe and a shoulder which supports the probe and that is for friction stir welding; an image acquisition step for obtaining an ultrasonic wave transmission image of the joint part using the ultrasonic waves; and a determination step for determining that the joint part has been joined if width-dimensions of the joint part obtained from the ultrasonic wave transmission image are equivalent to at least the outer diameter d of the probe and if no defect of a prescribed size or greater is found in a range equivalent to the outer diameter D of the shoulder or less in the ultrasonic wave transmission image.

Abstract: A method includes the following: an incidence step in which ultrasonic waves from an insertion side and the side opposite thereto of a tool are caused to be incident on a joint part when a workpiece is joined by the tool that has a probe and a shoulder which supports the probe and that is for friction stir welding; an image acquisition step for obtaining an ultrasonic wave transmission image of the joint part using the ultrasonic waves; and a determination step for determining that the joint part has been joined if width-dimensions of the joint part obtained from the ultrasonic wave transmission image are equivalent to at least the outer diameter d of the probe and if no defect of a prescribed size or greater is found in a range equivalent to the outer diameter D of the shoulder or less in the ultrasonic wave transmission image.

Abstract: The present invention relates to a technique for producing a jointed member by subjecting two to-be-jointed members which are contacted each other to friction stir welding. The method for producing a jointed member executes a dwelling step in which a probe is rotated only for a predetermined period at at least one of a probe starting point position which is a position of the probe for forming a joint starting point in the to-be-jointed member and a probe end point position which is a position of the probe for forming a joint end point in the to-be-jointed member.

Abstract: A method for manufacturing a panel structure in which a reference position of a first frame in an axial direction is first welded to one face of a face plate, a not-yet-welded position closest to the reference position in the axial direction is second welded to the one face, and welding is performed discontinuously to the one face from the not-yet-welded position closest to the reference position at portions on both sides in the axial direction on the basis of the reference position.

Abstract: A method for manufacturing a panel structure in which a reference position of a first frame in an axial direction is first welded to one face of a face plate, a not-yet-welded position closest to the reference position in the axial direction is second welded to the one face, and welding is performed discontinuously to the one face from the not-yet-welded position closest to the reference position at portions on both sides in the axial direction on the basis of the reference position.

Abstract: The present invention relates to a technique for producing a jointed member by subjecting two to-be-jointed members which are contacted each other to friction stir welding. The method for producing a jointed member executes a dwelling step in which a probe is rotated only for a predetermined period at least one of a probe starting point position which is a position of the probe for forming a joint starting point in the to-be-jointed member and a probe end point position which is a position of the probe for forming a joint end point in the to-be-jointed member.