中国物理B ›› 1997, Vol. 6 ›› Issue (8): 614-618.doi: 10.1088/1004-423X/6/8/007
石磊1, 庞文华1, 李晓光1, 周贵恩1, 张裕恒2, 冯勇3, 杜社军3, 周廉3
SHI LEI (石磊)a, FENG YONG (冯勇)b, PANG WEN-HUA (庞文华)a, DU SHE-JUN (杜社军)b, ZHOU LIAN (周廉)b, LI XIAO-GUANG (李晓光)a, ZHOU GUI-EN (周贵恩)a, ZHANG YU-HENGac
摘要: Undoped and WO3-doped Y-Ba-Cu-O ceramics have been slowly cooled in flowing oxygen or quenched in air from 900℃ to room temperature, after sintering at 900℃ for 3Oh in flowing oxygen. The ac susceptibility measurements show that the Tc of the quenched WO3-doped Y-Ba-Gu-O superconductor can reach 88K, while the undoped Y-Ba-Cu-O ceramic quenched in air is a non-superconductor. X-ray diffraction data show that WO3 does not enter into the YBa2Cu3O7-x lattice but forms all impurity phase. The WO3-doped YBCO specimens quenched in air consist of orthorhombic YBa2Cu3O7-x phase and an impurity phase which increases with increasing WO3 content. Raman spectra chow that oxygen contents are different for undoped and WO3-doped samples. It la suggested that suitable doping with WO3 can change the oxygen content and reduce the effect of thermal treatments on the superconductivity of Y-Ba-Cu-O system.
中图分类号: (Other heat and thermomechanical treatments)