Influence of praseodymium impurity on mechanical design performance and morphological features of hightemperature superconductors

In this thesis study, the changes of mechanical performance parameters, durable tetragonal phase, surface morphology appearance and basic mechanical characteristics of praseodymium doped Bi-2212 ceramic materials produced by standard solid state reaction method were examined in detail by Vickers microhardness (Hv) and scanning electron microscope (SEM). has been examined. Additionally, the elemental distributions of the produced samples were examined by the energy-dispersive X-ray spectrometry (EDX) method. EDX experimental results show that all prepared ceramic materials were successfully produced. In addition, maximum copper ions were detected in the crystal structure of Bi-2212 material prepared at x = 0.02 Pr ratio. Again, according to the Vickers microhardness results obtained, the optimum Pr contribution rate for the Bi-2212 crystal system was found to be x = 0.02. In this context, the presence of optimum doping ratio has caused an increase in slip systems in the Bi-2212 material, an increase in surface compression residual stress regions, and the formation of new chemical bonds between foreign and host atoms in the crystal structure. SEM measurements showed that this material has the most homogeneous surface among other materials. Again, it showed that this material has the best crystal quality, best connections between layers, smooth surface morphology, great particle dispersion and orientation. The increase in crystal quality reduced the porous structure and increased the interaction between grains. These results show that the optimum Pr-doped Bi-2212 ceramic material prevents the stress-induced phase transition and causes the development of durable tetragonal phasing, and accordingly, the Bi-2212 ceramic system offers the highest basic mechanical performance feature.