ChemInform Abstract: Kinetics and Formation of the 110 K Phase in the Bismuth-Lead- Strontium-Calcium-Copper-Oxygen System.

✍ Scribed by W. ZHU; C. K. KUO; P. S. NICHOLSON

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 31 KB
• Volume: 28
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199745025

✦ Synopsis

Kinetics and Formation of the 110 K Phase in the Bismuth-Lead-Strontium-Calcium-Copper-Oxygen System.

-Kinetics and mechanism of formation of the title phase, (Bi,Pb) 2Sr2Ca2Cu2Ox (110 K or 2223) are studied by high temp. XRD, SEM, TEM, and DTA methods. Analysis of the kinetic data, gathered for p(O2) values of ≈1-35 kPa (0.01-0.35 atm), using the Avrami equation show that the reaction is diffusion controlled. The growth of the 110 K phase starts at the grain boundaries of the (Bi,Pb)2Sr2Ca2Cu2Ox (80 K or 2212) phase and the growth rate depends on the rate of mass transport to the 110 K/80 K interface. The kinetics of formation are accelerated by a liquid which forms at ¿842 • C in air and is rich in Ca/Sr, Cu, and Pb. -