Effect of Mechanical Alloying on the Microstructure and Properties of C-Doped ${\rm MgB}_{2}$ Wire by Ex-Situ Process

We fabricated C-doped MgB
₂
wires using the
ex-situ
process via the mechanical alloying (MA) technique to improve the doping effect and evaluated the effect of MA and C content on the phase formation, microstructure, and critical properties. The mixtures of MgB
₂
and 0, 1, and 5 at% carbon black (CB) powders underwent MA using a planetary ball mill system for 25 hours. The powders were loaded into Fe tubes, drawn into wires, and sintered at 1000degC for 1 hour in flowing Ar gas.