FORMATION AND PHASE-DECOMPOSITION OF TEXTURED YBA2CU4O8 SUPERCONDUCTOR

Textured YBa2Cu4O8 SUPerconductor has been fabricated from melt-textur ed YBa2Cu3Ox by hot isostatic pressing (hipping). Under conditions of high oxygen partial pressure created by the oxygen released from the s uperconductor during hipping, the textured YBa2Cu3Ox is converted into YBa2Cu4O8. The textured YBa2Cu4O8 is then subjected to a short heat t reatment to decompose into YBa2Cu3Ox in order to introduce a fine-scal e defect structure. Transport-current measurements on the hipped and h eat-treated samples reveal that the superconducting transition tempera ture and the high J(c) are recovered after decomposition and the trans port J(c) increases with increasing heat-treatment times.