Title :
Kinetics of phase formation and transport properties of Bi-2223/Ag tapes fabricated by various calcined powders
Author :
Jiang, Chunhai ; Yoo, Jaimoo ; Ko, Jaewoong ; Chung, Hyungsik ; Qiao, Guiwen
Author_Institution :
Inst. of Metal Res., Chinese Acad. of Sci., Shenyang, China
fDate :
6/1/2003 12:00:00 AM
Abstract :
The kinetics of phase formation and transport properties of Bi-2223/Ag tapes fabricated by precursor powders with different phase assemblages have been studied. Our results show that the formation process of 2223 phase is strongly related to the secondary phases in precursors. A variation of the reaction-order, n, deduced from the Avrami relation, was observed along with the whole sintering processing. Within a sintering period of 65 h, n keeps the value of 0.7 for the tape made from the powder calcined at 830°C, while it changes from 0.3 or 0.4 to 1 for the tapes prepared with the powders calcined at 810°C and 820°C. Based on the analysis of phase formation and transport properties, the optimum calcination conditions for achieving high Jc tapes are discussed.
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); high-temperature superconductors; multifilamentary superconductors; phase diagrams; silver; sintering; strontium compounds; superconducting tapes; 65 h; 810 degC; 820 degC; 830 C; Avrami relation; Bi-2223/Ag tapes; Bi2Sr2Ca2Cu3O10-Ag; calcined powders; critical current density; phase assemblages; phase formation; reaction-order; secondary phases; sintering processing; transport properties; Assembly; Calcination; Kinetic theory; Machinery; Materials science and technology; Microstructure; Powders; Proposals; Research and development; Superconductivity;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2003.812060
