Large domain growth of Ag-doped YBaCuO-system superconductor

The effect of Ag addition on the phase diagram, solidification conditions and fabrication of large domain YBaCuO-system has been studied. Calcined powder of composition Y1.8Ba2.4Cu3.4O9-x with 0.5 wt.% Pt and 0, 1, 5, 10, 20 and 30 wt.% Ag was prepared. The melting point of each powder was measured by differential thermal analysis (DTA). A large domain (45 mm diameter and 20 mm thick) of the Ag-doped YBaCuO-system superconductor was prepared for each composition by a seeding and unidirectional growth technique which involved controlling the furnace temperature gradient. In order to assess the quality of the crystal orientation, the distribution of trapped flux density was measured. The entire sample was magnetized uniformly and the trapped magnetic field observed to form a single dome shape.