Improvement of Electromagnetic Properties for Y_1.5Ba₂Cu₃O_7−y Superconducting Bulk

Creating perforations in bulk superconductors and infusing them with a conductive metallic medium enhances the thermal conductivity and mechanical properties of ceramic superconductors. In this study, the top-seeded melt growth (TSMG) technique was employed along with die pressing to fabricate single-grain YBCO bulk superconductors with engineered perforations. These perforations were introduced into YBCO powder compacts using a specially designed die, without hindering YBCO grain growth during the TSMG process. Subsequently, the YBCO bulk samples underwent oxygenation and cooling to 77 K through a field cooling method. The trapped magnetic field distribution on the top surfaces of these bulk YBCO samples, both with and without perforations, was assessed using a Hall probe. This paper reports the perforation process in bulk superconductors and its effect on the trapped magnetic fields of single-grain YBCO superconductors. Notably, samples with engineered perforations exhibited a significantly lower number of pores compared to those without. The single-grain YBCO bulk superconductor with six 3 mm-diameter artificial holes demonstrated high trapped magnetic fields and magnetic levitation capabilities.