Melt processing of superconducting YBa_(2)Cu_(3)O_(7-partial deriv) thick films on AgPd substrates via atmosphere control

摘要

Superconducting YBa_(2)Cu_(3)O_(7-partial deriv) (123) c-axis textured thick films have been prepared on AgPd substrates by a modified screen printing and melt processing method. Heating the samples in an inert gas (N_(2)) has enabled melt processing to take place at lower temperatures than conventional YBCO thick film processing in O_(2). The atmosphere is switched to p(O_(2))=100% at peak temperature in order to initiate the crystallisation of the 123 phase. Variation in properties of the films with changes in the peak processing temperature has been investigated. Samples processed at peak temperatures of ≥980℃ show better microstructures and superconducting properties than those processed at lower temperatures. Quenching experiments have also been performed in order to investigate further the phase relationships and crystallisation mechanism of the 123 phase.