Abstract
Melt-textured growth of the YBa2Cu3O7-x phase from a supercooled melt created locally aligned, needle-shaped grains of the orthorhombic 1-2-3 phase. However, a strong wettability of the Cu-rich liquid phase (BaCuO2+CuO) on the (100) plane of MgO hindered complete formation of the 1-2-3 phase, and we observed the phase separation of the 2-1-1 phase (Y2BaCuOx) and Cu-rich precipitates from the stoichiometric melt of YBa2Cu3O7-x.