Fabrication and superconducting properties of ex-situ processed MgB2/Fe monofilament tapes without any intermediate annealing
Küçük Resim Yok
Tarih
2011
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
We have investigated the effect of annealing time and temperature on the formation of the MgB2 phase, transition temperature (T-c), lattice parameters (a and c), full width at half maximum (FWHM) of the X-ray diffraction, crystallinity, resistivity (rho), residual resistivity ratio (RRR), active cross-sectional area fraction (A(F)), and critical current densities (J(c)) of MgB2/Fe monofilament tapes fabricated using an ex-situ powder-in-tube (PIT) method without any intermediate annealing. To obtain the optimum annealing temperature, MgB2/Fe monofilament tapes were annealed at 650, 750, 850, 950, and 1050 degrees C for 60 minutes. From these investigations, the optimum annealing temperature was found to be 950 degrees C. Then, to obtain the optimum annealing time, the samples were annealed at 950 degrees C for 15, 30, 60, 120, 180, and 240 minutes. The samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS), optical microscope, critical transition temperature (T-c), and critical current density (J(c)) measurements. The transport and microstructure investigations show that T-c, J(c), and the microstructure properties are remarkably enhanced with increasing annealing temperature up to 950 degrees C. The highest value of the critical current density was obtained after annealing at 950 degrees C for 60 minutes. The J(c) and T-c(offset) c values of the sample annealed at 950 degrees C for 60 minutes were found to be 260.43 A/cm(2) at 20 K and 38.1 K, respectively.
Açıklama
Anahtar Kelimeler
MgB2/Fe Monofilament Tapes
Kaynak
Chinese Journal Of Physics
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
49
Sayı
3
