| Summary: | Dysprosium-doped at Ca site in low density Bi1.6Pb0.4Sr2Ca2-xDyxCu3Oy with varying stoichiometry (where x=0.000, 0.025, 0.05, 0.1 and 0.2) were prepared by solid state method. In this work, the samples were characterized by X-ray diffraction analysis (XRD), field emission scanning electron microscopy (FESEM), electrical resistance, and critical current density (JC) measurements. All of the results indicated deterioration on the superconducting properties due to the substitution of dyprosium at Ca site compared to undoped samples. It has been observed that the JC of low-density Bi-2223 at 60 K under zero magnetic field for Dy-free and x=0.050 (optimum doping level) was measured to be 12.120 A/cm2 and 1.547 A/cm2 respectively. Superconductivity transition temperature, TC of undoped samples were found to be higher than doped samples. For undoped samples the TC zero was observed at 102 K and it decreased to 55 K, 66 K, 40 K and 40 K for x=0.025, 0.050, 0.100, and 0.200 respectively. The XRD results showed the c-axis decrease as the Dy doping increase and the crystal structure of the doping samples changed from tetragonal to orthorhombic. FESEM results showed the surface morphology of Dy doping indicated a weaker link between grains compared to the undoped samples. © 2015, Malaysian Society of Analytical Sciences. All rights reserved.
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