Yazarlar |
Prof. Dr. Özgür ÖZTÜRK
Kastamonu Üniversitesi, Türkiye |
Doç. Dr. Elif AŞIKUZUN TOKEŞER
Kastamonu Üniversitesi, Türkiye |
Öğr. Gör. Dr. Şeydanur KAYA
Kastamonu Üniversitesi, Türkiye |
Murat Erdem
Abant İzzet Baysal Üniversitesi, Türkiye |
Serap Safran
Ankara Üniversitesi, Türkiye |
Atilla Kılıç
Abant İzzet Baysal Üniversitesi, Türkiye |
Cabir Terzioğlu
Abant İzzet Baysal Üniversitesi, Türkiye |
Özet |
The effects of Ar ambient pressure (vacuum and 0, 10, and 20 B) and annealing times (0.5 and 1 h) on microstructural, superconducting, and mechanical properties of bulk superconducting MgB2 are investigated. The samples are produced using the solid-state reaction method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements are performed for determination of the crystal structure and surface morphology of MgB2 samples, respectively. The superconducting properties are studied by AC magnetic susceptibility measurements. Microhardness analyses are made using the Vickers microhardness test for determination of mechanical properties of all samples. Increasing the Ar pressure decreases the lattice parameters and hence the average grain size. Increasing the annealing time results in larger lattice parameters and larger grain formation. The susceptibility measurements revealed a two-step transition which is reminiscent of granular superconductors. The intra-grain transition temperature is determined to be 38.4 K for all samples. The inter-grain transition temperature of 37.2 K is obtained for samples produced under Ar ambient pressure. The samples produced under Ar ambient pressure have better superconducting properties than the ones produced in vacuum. Increasing the annealing time under vacuum further decreases the superconducting properties probably due to Mg loss. |
Anahtar Kelimeler |
MgB superconductors 2 | SEM | Susceptibility | Vickers microhardness | XRD |
Makale Türü | Özgün Makale |
Makale Alt Türü | SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale |
Dergi Adı | Journal of Superconductivity and Novel Magnetism |
Dergi ISSN | 1557-1939 |
Dergi Tarandığı Indeksler | SCI-Expanded |
Makale Dili | İngilizce |
Basım Tarihi | 07-2015 |
Cilt No | 28 |
Sayı | 7 |
Sayfalar | 1943 / 1952 |
Doi Numarası | 10.1007/s10948-015-3003-z |
Makale Linki | http://link.springer.com/10.1007/s10948-015-3003-z |
Atıf Sayıları | |
SCOPUS | 9 |