MgB2 süperiletken külçe malzemesine altın kaplamasının etkileri

Öz

Magnezyum diborür (MgB₂) süperiletken külçe malzemeleri argon atmosferinde ex-situ (hazır toz) ve in-situ (Mg+2B) katıhal reaksiyon yöntemiyle hazırlanmıştır. Ex-situ/in-situ MgB₂ süperiletken örneklerin bir yüzeyine ~50 µm altın (Au) kalın film kaplaması yapılmıştır. Bir yüzeyi Au kaplı ex-situ/in-situ MgB₂ süperiletken örnekler 650^oC–850^oC sıcaklık aralığın da 1 saat tavlanmıştır. Bu malzemelerin X-Işını Kırınım (XRD) yöntemi kullanılarak mikro yapısal değişimi ve direnç-sıcaklık ölçümleri (R-T) ile elektriksel karakteristiği incelenmiştir. Au kaplamasıyla MgB₂ malzemesinin c örgü parametresi ve özkütlesinin arttığı gözlenmiş, aynı zamanda bazı tavlama sıcaklığında kritik geçiş sıcaklığı (T_c) iyileşme göstermiştir.      

Anahtar Kelimeler

• Ex-situ/In-situ MgB2 süperiletken külçe malzeme,Au kaplama

Effects of gold coated on MgB2 superconducting bulk samples

Öz

Magnesium diboride (MgB₂) superconducting bulk materials were prepared by the ex-situ (commercial powder) and in-situ (Mg + 2B) solid state reaction method in argon atmosphere. One surface of the ex-situ / in-situ MgB₂ superconducting samples was coated ~50 μm gold (Au) thick film. Au-coated surface of ex-situ / in-situ MgB₂ superconducting samples was annealed at temperature range from 650^oC to 850^oC for 1 hour. The microstructural properties and electrical characteristics of these materials were investigated by X-Ray Diffraction (XRD) method and resistance-temperature measurements (R-T), respectively. It has been found that the lattice parameter c and density of MgB₂ material were increased by coating Au, also the critical transition temperature (T_c) was improved at some annealing temperatures.

Anahtar Kelimeler

• Ex-situ/In-situ MgB2 superconducting bulk sample,Au coating

Kaynakça

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