International Journal of Advanced Applied Physics Research (Special Issue 1) |
Enhancement of Phase Formation and Critical Current Density in (Bi,Pb)-2223 Superconductor by Boron Addition and Ball Milling |
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Pages 1-5
N.G. Margiani, S.K. Nikoghosyan, Z.A. Adamia, D.I. Dzanashvili, V.S. Kuzanyan, N.A. Papunashvili, I.G. Kvartskhava, A.G. Sarkisyan and V.V. Zhghamadze
DOI: http://dx.doi.org/10.15379/2408-977X.2016.01 Published: 28 January 2016 |
Abstract |
The effects of crystalline boron addition and ball milling on the phase formation and transport properties of (Bi,Pb)-2223 HTS have been studied. Samples with nominal composition Bi1.7Pb0.3Sr2Ca2Cu3BxOy, x=0 - 0.5, were prepared via a solid state reaction route. Superconducting properties of undoped (reference) and boron-added (Bi,Pb)-2223 compounds were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), resistivity and transport critical current density (Jc) measurements. Obtained results have shown that boron additive leads to the acceleration of high-Tc phase formation and enhancement of Jc in (Bi,Pb)-2223 superconductor. The estimated volume fraction of (Bi,Pb)-2223 phase increases from ~25 % for reference specimen to ~75 % for x=0.15. Moreover, strong increase in the Jc was observed for the x=0.15 sample (Jc=340 A/cm2), compared to a reference sample (Jc=115 A/cm2). We have studied the effect of high-energy ball milling on Jc in reference and x=0.15 samples. Addition of B in combination with the ball milling leads to the further enhancement of Jc up to 490 A/cm2, whereas the ball milling of reference specimen causes the marked decrease in both Jc and Tc values. Improvement of superconducting properties in (Bi,Pb)-2223 superconductor can be attributed to the acceleration of high-Tc phase formation along with the enhancement of intergrain coupling due to the elemental boron addition. |
Keywords |
(Bi,Pb)-2223 phase, Crystalline boron additive, Ball milling, Electrical resistivity, Critical temperature,Critical current density. |
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