Thick Y--Ba--Cu--O Films on Corundum Substrates

摘要: The possibility of preparing superconducting thick films of YBa sub 2 Cu sub 3 O sub 7--x in a stream of air on cheap and widely used corundum substrates has been investigated with the aim of finding the relations between annealing regimes, structure and superconducting properties of films with good film surface quality and adhesion to the substrate. Specimens 40-60 mu m thick were prepared from particles approx 10 mu m in size and studied by X-ray diffraction. Annealing temperatures of 500-1000 deg C were studied, and the corresponding film electrical resistance measured. It was found that thick films of the system retaining the structure and superconductor properties of the starting powder can be prepared by annealing in air only in the annealing temperature range 920-930 deg C.