Effects of precursor powders and sintering processes on the superconducting properties of MgB2
Year: 2004
Type: article
Abstract: Different precursor powders and procedures were used to fabricate MgB 2 superconductor. It was found that the purity of the B powder had strong effects on the T c and J c of MgB 2 . The J c of the sample made from 90% B powder decreased 40 times at 3 T and 20 K compared with the 99% B powder samples. The impurity phases might be the reason for the suppression of the T c and the J c . Variation of the Mg:B ratio also influenced the MgB 2 properties. J c decreased with fluctuations from the normal rate (Mg:B = 1:2). It was found that the effects of the oxidization of the Mg powder on J c were not strong when the Mg powder was only slightly oxidized. However, when the Mg powder was severely oxidized, the J c decreased significantly. A two-step sintering process was adopted to make MgB 2 . In this process, the first sintering stage was at a lower temperature. It was found that this pre-sintering did not have a good effect on the properties, despite the fact that the mass density was improved. The phase composition and microstructure were analysed to explain the different effects.
Authors: Sihai Zhou, A V Pan, J Horvat, M J Qin, H K Liu
Institution: University of Wollongong
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2147652912