SOLIDIFICATION CHARACTERISTICS OF TEXTURED 123-PHASE IN YBCO BY LASER FLOATING-ZONE LEVELING (LFZL) METHOD

Because of incongruent melting in YBa2Cu3O7-x, it is difficult to grow the textured 123 phase directly from the laser-heated molten zone in the laser floating zone (LFZ) method. To overcome this problem, the laser floating zone leveling (LFZL) method was utilized following a pseudo-binary diagram along the Y2BaCuO5-YBa2Cu3O7-x tie line and a crystal rod of textured 123 phases was directly grown from the molten zone. Experimental results indicate that the orientation of the textured tetragonal 123 phases is perpendicular to the c-axis and that the T(c) of the grown crystal rod is 91.2 K after annealing at 550-degrees-C for 40 h in flowing oxygen. Also, the solidified morphologies of some crystal rods grown at different growth rates were observed.