Bismuth-based superconducting wire

Bismuth-based superconducting material was discovered in Japan. Sumitomo Electric is the world's first company to produce long bismuth-based superconducting wire, which has now become a global standard. Bismuth-based superconducting material is made of bismuth - strontium - calcium - copper - oxygen (Bi-Sr-Ca-Cu-O). The 2223 phase with composition ratio of Bi, Sr, Ca and Cu is 2:2:2:3 has high critical temperature (110 K) and therefore is attracting much attention as a commercially viable material since its discovery. Sumitomo Electric has been researching the solid phase method for combined processing of silver and bismuth-based HTS material. Using its innovative process called "Controlled Over Pressure (CT-OP)", quality and productivity for Bi-based HTS wires are improved substantially.



The improvement of critical current and other achievements were obtained by applying the CT-OP process during the research that was partly supported by the New Energy and Industrial Technology Development Organization (NEDO) through the International Superconductivity Technology Center (ISTEC) as collaborative research and Development of Fundamental Technologies of Superconductivity Applications.
   
source from sumitoto