Effect of nano-SiC and nano-si doping on critical current density of MgB2

The discovery of superconductivity in magnesium diboride (MgB
2
) has opened up a new field in materials science research. It offers a possibility of a new class of high performance superconducting materials for practical applications because of the relatively low cost of fabrication, high critical current densities (J
c
) and fields, large coherence length, absence of weak links, higher T
C
(T
C
= 39 K) compared with Nb
3
Sn and Nb-Ti alloys (two or four times that of Nb
3
Sn and Nb-Ti alloys). However, the weak flux pinning in the magnetic field remains a major challenge. This paper reports the most interesting results on nanomaterial (SiC and Si) doping in magnesium diboride. The high density of nano-scale defects introduced by doping is responsible for the enhanced pinning. The fabrication method, critical current density, microstructures, flux pinning and cost for magnesium diboride bulks, wires and tapes are also discussed. It is believed that high performance SiC doped MgB
2
will have a great potential for many practical applications at 5 K to 25K up to 5T.