Mechanical properties of YBCO and YBCO+ZnO polycrystalline superconductors using Vickers hardness test at cryogenic temperatures

Vickers hardness tests were carried out on YBCO and YBCO + 1 wt% ZnO polycrystalline superconductors from 40 to 293 K. It was found that the hardness was increased with 1 wt%ZnO addition to YBCO. Thermal activation energies of samples YBCO and YBCO + 1 wt%ZnO were found to be 0.0036 and 0.0026 eV, respectively. No creep was observed in the load–displacement experiments carried out for both samples at low temperatures, when the load was kept fixed for 15 s. It was detected that elastic recovery ratio of the 1 wt%ZnO added YBCO sample was higher than that of YBCO at both low temperature and room temperature.