Time-Dependent Diffusion Coefficient of Fe in MgB{sub 2} Superconductors

Journal Article · Fri Dec 15 00:00:00 EST 2017 · Journal of Superconductivity and Novel Magnetism

DOI:https://doi.org/10.1007/S10948-017-4113-6· OSTI ID:22771752

Belenli, Ibrahim ^[1]

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1. Abant Izzet Baysal University, Department of Physics, Faculty of Arts and Science (Turkey)

The iron (Fe) diffusion in superconducting MgB{sub 2} bulk samples has been studied for sintering time durations of 15 min, 30 min, 1 h, 2 h, and 4 h at 900{sup ∘}C. Fe coating bulk polycrstalline superconducting MgB{sub 2} samples for Fe coating were prepared by pelletizing and used in the diffusion experiments with initial sintering at 800{sup ∘}C for 1 h. A thin layer of Fe was coated on MgB{sub 2} pellets by evaporation in vacuum. Effects of Fe diffusion on the structural, electrical, and superconducting properties of MgB{sub 2} have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR), energy-dispersive X-ray spectroscopy (EDS), and resistivity measurements. Fe diffused samples have slightly increased critical transition temperatures and have larger lattice parameter c values, in comparison with bare samples. Fe diffusion coefficients were calculated from depth profiles of c parameter and room temperature resistivity values. Depth profiles were obtained by successive removal of thin layers from Fe diffused surfaces of the samples. Our results have shown that the Fe diffusion coefficient decreases with increasing sintering time and resistivity measurements can be utilized for determination of diffusion coefficient.

• OSTI ID: 22771752
• Journal Information: Journal of Superconductivity and Novel Magnetism, Vol. 30, Issue 12; Other Information: Copyright (c) 2017 Springer Science+Business Media, LLC, part of Springer Nature; Article Copyright (c) 2017 Springer Science+Business Media New York; http://www.springer-ny.com; Country of input: International Atomic Energy Agency (IAEA); ISSN 1557-1939
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTROSCOPY
DIFFUSION
EVAPORATION
INFRARED SPECTRA
IRON
LATTICE PARAMETERS
MAGNESIUM BORIDES
PELLETIZING
PELLETS
POLYCRYSTALS
SCANNING ELECTRON MICROSCOPY
SINTERING
SUPERCONDUCTORS
SURFACE COATING
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
TIME DEPENDENCE
TRANSITION TEMPERATURE
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY