Kozyrev A. Scientific fundamentals of the thermobaric formation of the nanostructure of MgB2-based electrotechnical materials with high level of superconducting properties

The dissertation is devoted to solving the actual scientific and technical problem of creation of MgB2-based superconducting materials for electrotechnic which has been successfully solved by establishment of patterns of thermobaric formation of superconducting nanostructure and pinning mechanisms. This allowed achieving the highest values of superconducting characteristics than known from the literature and developing manufacturing technologies of MgB2-based superconducting materials with properties and dimensions necessary for their effective use in superconducting electric machines, current limiters and powerful magnets operating at boiling temperatures of liquid hydrogen and neon. It been shown that high level of critical current density in MgB2, as well as in solid solutions MgB2-xOx with MgB2 structure, is achieved due to forming a nanostructure with a high content of dispersed inclusions or nanolayers of Mg-B-O and higher magnesium borides by pinning on the boundaries of these phases.