THE EFFECTS OF Y2BACUO5 SUBSTRATE ON THE MELT-TEXTURED GROWTH OF YBA2CU3O7-DELTA CRYSTALS

The effects of contact area as well as the weight fraction of Y2BaCuO5 (211) substrate on the melt textured growth (MTG) of YBa2Cu3O7-delta (123) crystals are investigated. It is found that the 123 grain size a nd its orientation have been greatly improved by a well designed 211 s ubstrate with maximized number of contact points. The size of the 123 single domain has been extended up to 2.7 cm with no porosity and crac ks by applying 50% of contact area and 35% of absorbed liquid weight i nto 211 substrate. magnetization and levitation measurements show that the MTG 123 crystals have a high J(c) and a good performance in high magnetic fields.