Effect graphite on magnesium diboride superconductivity synthesized by combustion method under argon pressure: Part I

Solid-state synthesis of a superconductor based on magnesium diboride doped by graphite microparticles (MgB2@C) at argon atmosphere has been described. The offered method allows the possibility to increase the critical current density of the studied samples at relatively low temperature in the inert environment. The superconducting characteristics of samples critical current density (Jc) and critical transition temperature (Tc) have been measured. The impact of the doping additives on superconducting characteristics of magnesium diboride has been analyzed. The results showed that the best optimal characteristics are for MgB2@3%C that reveals a good critical transition temperature 38,8 K and the higher critical current density 2,7 x 106 A / cm2 at 5 K