Thermal and Mechanical Investigations of (Bi,Pb)-2212 superconductor added with different oxide nanoparticles

Abstract In this study, superconducting samples of type Bi1.6Pb0.4Sr1.9Ca1.1Cu2.1Oy,(Bi, Pb))-2212, added with CdO, CdMnO, and CdFeO nanoparticles, were synthesized using a solid state reaction technique. The samples were examined using X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Thermogravimetric analysis (TGA) was utilized to evaluate the thermal stability of the pure sample throughout the different stages of the phase formation and the effect of the nanoparticles addition. The weight loss/gain by the three additions is related to the excess of oxygen, confirmed via Iodometric titration analysis and from the findings of oxygen diffusion energy using TGA data. Vickers microhardness measurements were conducted at various applied loads (0.49–9.8 N). All of the prepared samples displayed a typical 'indentation size effect' (ISE) behavior based on the HV measurements. It was found that the optimum addition of nanoparticles, for increasing the microhardness of the (Bi, Pb)-2212 phase, was at x = 0.05 wt. %. Furthermore, various mechanical properties as Elastic modulus (E), yield strength (Y), fracture toughness(K), and brittleness index (B) were calculated for three additions of the samples studied. As for the theoretical examination of HV in the saturation limit regions, the indentation-induced cracking (IIC) model wins the comparison.