Abstract: A testing method for a joined body, in which a second pipe member having an outer diameter smaller than that of a first pipe member having at least one through hole is inserted into the first pipe member and the second pipe member is expanded to form a joining portion, the testing method includes: applying an elastic wave vibration to the joined body of the first pipe member and the second pipe member, for plural visual field regions at different positions in a circumferential direction of the joined body, acquiring a vibration distribution of the second pipe member measured through the through hole and a vibration distribution of the first pipe member in a visual field region including the joining portion of the first pipe member and the second pipe member, which are measured optically and in a batch, and determining quality of joining in the entire joining portion based on the acquired vibration distributions.

Abstract: An electromagnetic forming method includes: a step of setting pipe periphery members at plural positions along an axial direction of a pipe material; a step of setting a coil unit on a side of one end, in the axial direction, of the pipe material, the coil unit including a conductor wound portion, conductor extension portions, and a resin-made conductor support portion; a step of setting a support member on a side of the other end, in the axial direction, of the pipe material; a coil unit holding step; a coil setting step; and a swaging step. The coil setting step and the swaging step are performed in this order at each of the plural positions of the pipe material while the coil unit is kept held by the support member.

Abstract: An electromagnetic forming method includes: a step of setting pipe periphery members at plural positions along an axial direction of a pipe material; a step of setting a coil unit on a side of one end, in the axial direction, of the pipe material, the coil unit including a conductor wound portion, conductor extension portions, and a resin-made conductor support portion; a step of setting a support member on a side of the other end, in the axial direction, of the pipe material; a coil unit holding step; a coil setting step; and a swaging step. The coil setting step and the swaging step are performed in this order at each of the plural positions of the pipe material while the coil unit is kept held by the support member.