Process for the production of a coil made of a high temperature superconductor material, and a high-temperature superconducting coils having low AC loss

A process for the production of a superconducting coil, comprising:

• a) processing a shaped article produced using a melt cast method, if it is not provided with a cavity such that the shaped article is hollow, to form a hollow article, wherein the shaped article is made of a material which is superconducting or which becomes superconducting upon heat treatment,
• b) then providing the hollow article with incisions or cuts in the form of the future coil geometry,
• c) filling the incisions or cuts with a reinforcing material, and/or applying a reinforcing material externally to the shaped article,
• d) in the case of incisions, which only go partially through the article from the outside, internally machining the hollow article until the incisions become cuts, which go completely through the article from the outside to the inside, and
• e) partially or fully removing the reinforcement externally or internally from the hollow article.