Study on YbBaCuO superconductor of Yb2O3-BaCO3-CuO

The preparation of YbBaCuO superconductor was investigated due to its lower melting point than YBaCuO. DTA measurement showed that the melting point o f YbBa2Cu3Ox was about 980 degrees C, which was 30 degrees C lower than tha t of YBa2Cu3Ox compound. But the liquid phase appeared at 910 degrees C, me aning YbBa2Cu3Ox began to decompose below 980 degrees C. Therefore, solid s tate sintering process of YbBa2Cu3Ox should be taken place below 910 degree s C. The SmBaCuO crystals were used as seeds to introduce the large YbBaCuO crystal growth. In the melt-condensed process, the heating temperature was reduced from 980 degrees C to 900 degrees C during 40 h, in that period th e textured YbBaCuO was well-grown. The structure of textured YbBaCuO was ob served with SEM and XRD, and the zero resistance superconductivity and the critical current density of textured YbBaCuO were at 86 K and 770 A/cm(2) ( 77 K, 0 H), respectively. (C) 2000 Elsevier Science B.V. All rights reserve d.