a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein the shape size and regions and the like of the drawing may be exaggerated for clarity hereinafter exemplary embodiments of a superconducting cable will be described in detail with reference to the accompanying drawings fig2 and 3 show cross sectional views of dies used for a manufacturing process in which cryostats are subjected to hot extrusion the superconducting cable according to this embodiment has a core positioned therein an inner cryostat surrounds a periphery of the core and a heat insulating tape surrounds a periphery of the inner cryostat to form a heat insulating layer in addition an outer cryostat surrounds a periphery of the heat insulating layer in the superconducting cable configured as described above the inner cryostat is manufactured by a hot extrusion method from 100 series aluminum of purity 99 or higher or al u2014 zn alloys such as a1050 a1100 a2017 a2014 a3003 a3004 a5052 a5n01 a5083 a6061 a6n01 a6063 a7003 and a7075 hereinafter collectively referred to as u201c aluminum u201d since the inner cryostat is manufactured by the hot extrusion method a welded site is not formed in the inner cryostat the existing inner cryostat is formed by bending stainless steel into a circular shape welding bent end parts and grinding the welded sites to smooth the surface thereof however since the inner cryostat according to this embodiment.