Abstract
The effect of BaSnO3 nanoparticles addition on the structural and mechanical properties of (Bi, Pb)-2223 superconducting phase by means of X-rays diffraction analysis (XRD), scanning electron microscope (SEM), electrical resistance and Vickers microhardness measurement was studied. BaSnO3 nanomaterial and (BaSnO3)(x)(Bi, Pb)-2223 superconducting samples were prepared using co-precipitation method and standard solid-state reaction techniques, respectively. From XRD data, the addition of BaSnO3 into (Bi, Pb)-2223 phase does not affect the tetragonal structure and the lattice parameters. SEM images indicate that the microstructure of (Bi, Pb)-2223 was enhanced by adding BaSnO3 nanoparticles by filling its pores and voids. The superconducting transition temperature T-c as well as the critical transport current density J(c), estimated from electrical resistivity measurements, are increased up to x = 0.5 wt%, then decreased with further increase in x. Vickers microhardness measurements H-v were carried out at room temperature as a function of applied. The experimental H-v results were analysed in view of Meyer's law, Hays and Kendall (HK) approach, elastic/plastic deformation (EPD) and proportional specimen resistance (PSR). All samples exhibit normal indentation size effect (ISE), in addition to that, the analysis shows that the Hays and Kendall model is the most suitable one to describe the load independent microhardness for (BaSnO3)(x)(Bi, Pb)-2223 superconducting samples.