Effect of Addition of TiO{sub}2/SiO{sub}2 Nanoparticles on H{sub}(c2) and H{sub}(irr) in MgB{sub}2 Bulks

摘要

In this paper, MgB{sub}2 bulks were prepared with doped TiO{sub}2 nanoparticles surface-modified by 5-10% SiO{sub}2. Quantitative X-ray diffraction (XRD) analysis was performed to obtain the weight fraction of impurities using the Rietveld method. The effects of addition of TiO{sub}2/SiO{sub}2 nanoparticles on the critical temperature (T{sub}c), the upper critical field (H{sub}(c2)), and the irreversibility field (H{sub}(irr)) as a function of doping rates at 750°Care reported. It has been found that the addition of TiO{sub}2/SiO{sub}2 nanoparticles resulted in small depressions in T{sub}c, while the H{sub}(c2) and H{sub}(irr) performances were improved due to TiO{sub}2/SiO{sub}2 nanoparticle doping.