Properties of ca doped in non-porous and porous of Y3CaBa4Cu8Oy compared to non-porous and porous of YBa2Cu3Oy ceramics / Zuliana Salmee Zainal Abidin

All samples powder were prepared using solid state method involved a series of heating and grinding. Ca was doped in Ba site of Y3Ba4CusOy superconductor. Sucrose was adding during pelletization and after that firing at 400°C in a furnace, open pores were created. Then all samples were final sintered at 950°C in open atmosphere. These samples characterized through using the X^ay diffraction (XRD) for phase evaluation, scanning electron microscopy (SEM) for grain morphology, and He closed cycle four point probe to determine the critical temperature, Tc and critical current density, Jc, Experimental results showed that the critical temperature, Tc depends on Ca substitution. When Ca doped in YaBa^ugOy, the value of critical temperature decreased, it is lower than critical temperature of YBa2Cu30y. From the graph represent resistivity versus temperature, the major phase is orthorhombic and most of the sample shows metallic behaviour.