Improved irreversibility behavior and critical current density in MgB2-diamond nanocomposites

MgB2-diamond nanocomposite superconductors have been synthesized by addition of nanodiamond powder. Microstructural analysis shows that the nanocomposite superconductor consists of tightly packed MgB2 nanograins (∼50–100 nm) with highly dispersed and uniformly distributed diamond nanoparticles (∼10–20 nm) inside the grains. The Jc–H and Hiir–T characteristics have been significantly improved in this MgB2-diamond nanocomposite, compared to MgB2 bulk materials prepared by other techniques. Also, the Jc value of 1×104 A/cm2 at 20 K and 4 T and the Hirr value of 6.4 T at 20 K have been achieved.