  A comparative study of pure, SiC, and C doped MgB2 wires has revealed that
the SiC doping allowed C substitution and MgB2 formation to take place
simultaneously at low temperatures. C substitution enhances Hc2, while the
defects, small grain size and nanoinclusions induced by C incorporation and low
temperature processing are responsible for the improvement in Jc. The
irreversibility field (Hirr) for the SiC doped sample reached the benchmarking
value of 10 T at 20 K, exceeding that of NbTi at 4.2 K. This dual reaction
model also enables us to predict desirable dopants for enhancing the
performance properties of MgB2.
