ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
An isothermal transformation curve marking the orthorhombic (O) to tetragonal (T) phase transition boundary has been established over a wide temperature range. There exists within the time-temperature-transformation diagram two distinct and separate regions containing superconducting samples with narrow 90- and 60-K transition temperatures, respectively. An oxygen diffusion coefficient at 300 °C in these materials is estimated based on isothermal data. The kinetic process of the T-O transformation is studied. It is found, at all temperatures investigated, that extended annealing reduces the normal-state conductivity of the material and that the best samples are produced for intermediate annealing times.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.340360
