Indexed on: 01 Apr '91Published on: 01 Apr '91Published in: Bulletin of Materials Science
EnhancedTc in calcium-free Tl compounds of the series TlmBa2Can−1CunOx (2201) has been reported. Three different starting compositions (2201, 1201 and 2202) were studied extensively with varying conditions of preparation. Under optimized conditions (sintering temperature 970°C and duration 3–10 min) the highestTc(onset) ranges from 103 K to ∼ 115 K andTc (zero) ∼ 95 K was found. XRD studies showed the transformation of all the three nominal compositions into 2201 phase with differentTcs.