The flux pinning properties of yttrium substitution in Bi-2223 superconductor / Siti Sarah Nordin

This report present the study of flux pinning properties as well as the
superconducting properties of Bi1.6-xYxPb0.4Sr2Ca2Cu3O superconductor. The
samples with varying value of Y (x =0.00, 0.02, 0.05, 0.10 and 0.20) were prepared
by using solid state method. The samples were characterized by using four point
probe and X-ray diffraction (XRD). The critical temperature, Tc and critical current
density, Je measurement were done using four point probe method without applied
magnetic field. Pure sample (x = 0.00) was observed to have the highest value of
Tc and Jc. The Tc (onset) and Tc (zero) for pure sample are 111 K and 97 K respectively.
The Jc value for pure sample is 1.590 A/cm2 at temperature 40 K. The flux pinning
properties were observed using four point probe method with applied magnetic field
varying from O.OOT to 0.33T. The Jc-B characteristic show that pure sample has
better flux pinning properties compared to other samples and has the better peak
position of Fp/Fpmax in the magnetic field. The XRD pattern shows that all samples
exhibit orthorhombic structure and peak at 20 = 26° is being diminished at x =
0.10 and 0.20. From the results, it is show that yttrium substituted samples reduced
the superconducting properties and as well as the flux pinning properties of the Bi2223
superconductor.