USE OF HIGH-DENSITY Y2BACUO5 SUBSTRATES IN THE MELT PROCESSING OF YBA2CU3O7-X BARS WITH HIGH TRANSPORT CRITICAL-CURRENT

Y2BaCuO5 (211) bars sintered at high temperatures were used as substra tes in melt processing of long YBa2Cu3O7-x (123) bars. Use of high-den sity 211 substrates (sintered at 1250 degrees C for 12 h) resulted in less liquid extraction, as compared to low-density 211 bars (sintered at 940 degrees C for 24 h). In addition, it was found that the high-de nsity bars influence the texture of 123, as domains were observed to g row from the 211/123 interface. A 6 cm long single domain sample with a cross-sectional area of 0.54 cm(2) was melt processed by using a 211 substrate. A de transport critical current of 1500 A along the c-dire ction of this full-length bar was measured at 77 K and in a self-field .