Yba2Cu3O7-x melt-textured thick films deposited on alumina-toughened zirconia substrate

Melt textured superconducting YBCO films with an approximate thickness of 50-120 mu m and Tc(0) values ranging between 86.5 and 88.5 K have been prepared on polycrystalline yttria-stabilized zirconia substrate, toughened by 20 wt.% Al2O3. Between the substrate and superconducting film an interface layer was formed Their AC and DC magnetization characteristics were measured and the values of the magnetic penetration field Hp, were estimated. The penetration field Hp, of 2.7 kA m(-1) was If obtained for the thinner film deposited with a higher spin coating rate, while for the thicker film deposited with a lower spin coating rate H-pl = 4.4 kA m(-1). Repeated temperature cycling between room and liquid nitrogen temperatures and corresponding measurement of the magnetization hysteresis curves reveal the significant decrease of the grain superconducting properties caused probably by arising cracks.