پديد آورنده :
عبدالحسيني سارسري، اسماعيل
عنوان :
بررسي اثر اندازه ي دانه ها بر خواص ساختاري الكتريكي و مغناطيسي سيم ابر رساناي Bi-2223/Ag
مقطع تحصيلي :
كارشناسي ارشد
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده فيزيك
صفحه شمار :
ده، 119، [II] ص.: مصور، جدول، نمودار
يادداشت :
ص. ع. به فارسي و انگليسي
استاد راهنما :
هادي سلامتي
استاد مشاور :
پرويز كاملي
توصيفگر ها :
ميدان بحراني , ميخكوبي شار , كلوخه سازي , فاكتور وامغناطش
تاريخ نمايه سازي :
31/2/86
استاد داور :
علي اكبر بابايي، محسن ذهبي
تاريخ ورود اطلاعات :
1396/02/31
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتال
چكيده انگليسي :
Abstract In this study we have prepared and studied superconducting properties ofBi1 66 Pb0 34 Sr2 Ca2 Cu3 Oy Bi2223 wires First we have studied the effect of precursorpowder size on the microstructure and intergranular behavior of polycrystalline of Bi2223superconductors using the XRD SEM electrical resistivity and AC susceptibilitymeasurements Polycrystalline of Bi2223 superconductors were prepared from the powderswith different milling times The XRD results show that by decreasing precursor powdersize the Bi2223 phase fraction increase It was found that the grain size and grainconnectivity improved by decreasing precursor powder size Analysis of the temperaturedependence of the AC susceptibility near the transition temperature Tc has been doneemploying Bean s critical state model The observed variation of intergranular criticalcurrent densities Jc with temperature indicates the decreasing of precursor powder sizein the Bi2223 system causes an increase in the intergranular critical current density Theeffect of particle size on the AC losses penetration depth and resistivity n of Bi 2223superconductors have been studied We have estimated the effective volume fraction of thegrains in the the framework of the critical state model based on the experimental results Second superconducting Bi1 66 Pb0 34 Sr2 Ca2 Cu3 Oy wires were prepared by powder intube PIT method and their superconducting properties were studied Our new studies on Bi 2223 Ag wire shows the presence of Ag and grinding timeenhance the transition temperature and the critical current of Bi 2223 phasesuperconductor wire The Ac susceptibility measurements were performs down to 77K using a Lake Shoresusceptometer Model 7000 The resistivity measurements were carried out by the fourprobe method using modified Lake Shore susceptometer down to 77K and a LeyboldClosed Cycle refrigerator down to 10K The microstructures of the sintered powder andselected wire samples were examined by scanning electron microscopy Phillips XL30 The critical current density was measured by the standard four probe technique
استاد راهنما :
هادي سلامتي
استاد مشاور :
پرويز كاملي
استاد داور :
علي اكبر بابايي، محسن ذهبي
