PURPOSE: To manufacture a wiry multi-core multi-layer ceramic superconductor with excellent superconductor characteristic, particularly high critical current density, by applying the cross section reduction machining for each layer of a composite tape on a metal core material.
CONSTITUTION: Butt sections of both edge sections of a composite tape with the width about 32mm are seam-welded on a round bar made of Ag with the outer diameter 4mm, for example, to form a composite body. This composite body is heated for a preset period at the preset temperature in the atmosphere, and swage machining is applied by roll machining to reduce the cross section until the outer diameter of the composite body becomes 10mm, for example. This process is repeated multiple times, and the outer diameter of the composite body is made 5mm, for example, by the final swaging machining. The heat treatment under the same condition is then applied to obtain a ceramic superconductor with eight-layer ceramic superconductor layer, for example. A wiry multi-core multi-layer ceramic superconductor with more excellent superconductor characteristic, particularly high critical current density, as compared with the multi-core multi-layer ceramic superconductor manufactured in the conventional method is manufactured.