New High Tc-Value Investigated in Superconducting System YBa2（C u3）1-xA gxO6.5x＋δ  

作　　者：Emad K. Al-Shakarchi Salwan K.J. Al-Ani Wedad. M. Faysal 

机构地区：[1]Physics Department, College of Science, Al-Nahrain University, Baghdad, Iraq [2]Physics Department, College of Science, Baghdad University, Baghdad, Iraq

出　　处：《Journal of Physical Science and Application》2012年第9期352-358,共7页物理科学与应用（英文版）

摘　　要：A ceramic superconductor compound with composition YBa2（C u3）1-xA gxO6.5x＋δhas been prepared experimentally by solid state reaction from principal roots of high purity materials like Y203, BaO, CuO and Ag20. The study was concentrated on the effect of partial substitution of Ag with respect to Cu atoms by the ratios （x = 0, 1, 0.2, 0.3, 0.4 and 0.5） through different analysis and measurements. X-ray diffraction （XRD）, Scanning Electron Microscope （SEM） and Resistivity measurement is play an important role to show the improvement on high superconducting phase. It was found that the best substituted value of （x = 0.5） investigated a favor value of Tc equal nearly to （123 K）, due to more excess of Ag atoms in the structure. X-ray diffraction showed an orthorhombic structure related to high-To phase with high stability through diminishing some peaks related to low temperature superconducting phase, that was related to presence of multiphase derivative from YBCO-phase. SEM pictures give us more details on the surface morphology, grain and grain boundaries, it gives an indication on successful of sintering process, the last one is very important in forming superconducting phase.

关 键 词：Superconductor compound 123-compound resistivity measurements X-ray diffraction. 

分 类 号：O511[理学—低温物理] O614.612[理学—物理]