Modulus and hardness evaluation of polycrystalline superconductors by dynamic microindentation technique

In this study, depth-sensing Vickers indentation tests were conducted on polycrystalline superconductors under different peak load (0.49, 0.73, 0.98, and 1.22 N). The load (P)–penetration depth (h) curves were analyzed in order to evaluate the mechanical characteristics such as microhardness and elastic modulus. It was found that both of these characteristics exhibited significant peak load dependence which suggested a need for calculation of the load-independent hardness and modulus. The load independent hardness (0.88, 0.95, and 1.12 GPa) and modulus (1.98, 3.13, and 3.33 GPa) values were then calculated for YBCO, YBCO + 0.5% ZnO, and YBCO + 1% ZnO, respectively.