Аннотация
Synthesis of the magnesium diboride doped by microparticles of barium oxide (MgB2@BaO) composites using a solid-state reaction method has been described. The proposed method gives the possibility to enhance the critical current density of the investigated samples at low temperature in the inert atmosphere. The superconducting parameters (Tc and Jc) have been measured. The influence of the doping agents on superconducting parameters of MgB2 has been analyzed. Obtained results revealed that the best optimal parameters are for 0.7MgB2@BaO sample that shows the highest critical transition temperature 39.3 K and critical current density 1.7*106 A/cm2. It was found that an increasing BaO content leads to the formation of a useful phase of BaB6, which demonstrates positive effects on the superconducting properties, acting as the effective pinning centers.