Superconductor Science and Technology · 2019 · 15 citations · 41 references
Natural SciencesMaterials SciencePhysicsCeramicsCondensed Matter PhysicsNanomaterialsFracture MechanicsGrain GrowthGrain Structure AnalysisGrain Structure FormationMagnetic OxidesSuperconducting MaterialsCerium Oxide NanoparticlesCrack FormationFerrimagnetic OxidesInfiltrationMicrostructureMicrostructure ObservationsRare-earth OxidesSuperconducting Ceramics
Abstract YBCO bulk single-grain samples with and without cerium oxide addition, were prepared by the two-step top seeded infiltration growth. The microstructure observations showed that cerium oxide addition led to formation of small Y 2 BaCuO 5 (Y211) particles in the YBa 2 Cu 3 O 7 single-grain matix. On the other hand, the sample without cerium oxide addition exhibited clusters of large Y211 particles. Observed difference in Y211 paricles led to significantly different size of a/c-oxygenation cracks. While the mean length of a/c-cracks in the sample with cerium oxide addition was several hundred micrometers, it was smaller than 50 μ m in the sample without cerium oxide addition. It was shown that the clusters of large Y211 particles can effectively prevent extension of oxygenation a/c-cracks. The trapped magnetic field measured at 77 K is shown.
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