The doping effect of Ti and Zr on the superconducting properties and the microstructure of sintered MgB2 bulk materials has been studied. The transition metal is found to work as a sintering assistant, which significantly enhances the grain connection of the MgB2 bulk materials during sintering processing. With this technique, we have fabricated Ti-doped MgB2 bulk materials consisting of fine 10 nm scale particles and achieved a high Jc over 1 MA/cm2 in 0 T at 20 K. The large enhancement of Jc is explained by the excellent connection between grains and a high density of pinning centers served by grain boundaries and MgO nanoparticles.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering