Effect of heat treatment on the phase transformation and magnetic properties of BPSCCO/LPMO composites

Bulk superconducting composites containing Bi1.6Pb0.4Sr2Ca2Cu3Oz (BPSCCO) and La0.6Pb0.4MnO3(LPMO) ceramics have been produced and investigated. The initial components were prepared by a solid-state reaction. The submicron powders mixed in weight ratio 99/1, 97/3, and 95/5 BSCCO/LPMO were heat treated at 840 °C for 24 h in oxygen atmosphere. The transformation and degradation of composites were studied in details by XRD, scanning electron microscopy (SEM), and the method of energy dispersive X-ray spectroscopy (EDX). It was established that the superconducting BPSCCO-2212 phase is predominate in the composites. Part of the ferromagnetic La0.6Pb0.4MnO3 phase was transformed in more complicated solid solution preliminary expressed by the formulae La(1−x−y)Pbx(Sr,Ca)yMn1−zCuzO3. AC magnetization MAC(T) and hysteresis loops M(H) of the composites were performed by Physical Property Measurement System (PPMS). It was observed the presence of both superconducting and magnetic phases in the composites after heat treatment.