Characterizations of the surfaces of shocked-Bi–Pb–Sr–Ca–Cu–O particles for a magnetic sensor

Abstract

Bi–Pb–Sr–Ca–Cu–O (BPSCCO) oxide superconductors are very attractive material as a highly sensitive magnetic sensor by using BPSCCO calcined powder. And it is found that the magnetic sensitivity increases as the value of critical current density (Jc) increases. Researches for applications of high-Tc BPSCCO particles have been made to overcome the weak-link problem around the grain boundaries for higher Jc. Shock compaction for BPSCCO particles have been investigated to obtain higher Jc by shock compaction technique. From x-ray diffraction (XRD)-analysis, it is found that the (BiPb)2Sr2Ca2Cu3Ox (Bi-2223) phase appeared after the shock compaction process under 3.79GPa and annealed at 850°C for 48h with the (BiPb)2Sr2Ca1Cu2Ox (Bi-2212) phase. From atomic force microscope (AFM) image of the surface for BPSCCO specimens after shock compaction and annealed at 850°C for 48h, it is found from the section analysis that the surface of the specimens for shocked BPSCCO particles has large grains of 8–10μm in length pa...