Preparation of YBCO superconducting thick film by electrophoresis

The thick films of YBa2Cu3Ox (YBCO) superconductor were prepared by electrophoretic deposition, using pre-sintered YBCO powder dispersed in acetone solution. The alumina (Al2O3) ceramic plate, coated with Ag, was used as the cathode substrate and the stainless steel mesh electrode was used as the counter electrode in suspension for electrophoresis. The conditions of applied voltages and temperatures, contents of iodine additives, and deposition times for electrophoretic deposition of YBCO thick films were studied in detail. As a result, the optimum value of iodine content in acetone was 200 mg/l, the applied electrical potential for electrophoresis was 200-300 V for 10 mm electrode gap, and the content of YBCO powder was 10-20 g/l in acetone suspension solution. The critical temperature was determined at 91 K by AC susceptibility curve and the critical current density, J(c), was measured by a four-point prove method at the value of 700 A/cm(2) deposited on the Ag coated Al2O3 substrate and 1456 A/cm2 deposited on the Ag wire (77 K, 0 T). (C) 2000 Elsevier Science B.V. All rights reserved.