Influence of Carbon Content on Superconductivity of Bi2Sr2CaCu2Ox
Deawha Soh1, Zhanguo Fan2, N. Korobova3
1Dept. of Electronic Engineering, Myongji University,
San 38-2, Nam-dong, Yongin-city, Kyunggi-do 449-728, Korea.
2Sch. of Material Science and Metallurgy, Northeastern University, China
3SHS lab., Combustion Problems Institute, Kazakhstan
Bi2Sr2CaCu2Ox was prepared by the conventional method of solid state reaction and SHS method. The samples were annealed in different atmosphere in order to examine the influence of atmospheres on the carbon contents in the Bi2Sr2CaCu2Ox compound. The lowest carbon content in Bi2Sr2CaCu2Ox could be attended when the sample was annealed in O2 at 800°C for 100 hours. The CO2 in air pollute the samples and increase the carbon content in the sintering process. The critical current density of the Bi2Sr2CaCu2Ox samples will decrease with the increasing carbon contents in the samples. The impurity carbon will deposit in the grain boundary, which makes critical current density lower.