Preparation of Novel High Temperature Superconductor Compounds (Cu-1223 and Sn-1223) From Hg-1223

number: 
3958
إنجليزية
department: 
Degree: 
Author: 
Israa Maher Jamal Taher
Supervisor: 
Prof. Dr. Emad Khudair Al-Shakarchi
year: 
2017

The main problem is the replacing of Hg atom by covalent atoms such as (Cu,Sn) atoms in the compound ((H )B C C ) by consider (x=0-1). Firstly, the high temperature superconductor of (HgB C C ) Hg-1223 had been synthesized experimentally by solid state reaction. The high temperature superconductor (CuB C C ) Cu-1223, (SnB C C ) Sn-1223 had been synthesized by solid state reaction.There are many parameters affected the preparation technique such as flow of oxygen, sintering temperature and compacted pressure. The ceramic samples of((HgB C C ),(CuB C C ) and (SnB C C ) was analyzed by XRD technique to show the phase of Hg-1223. The XRD-pattern exhibited the presence of Hg-1223, Cu-1223 and Sn-1223 like tetragonal phase incomparable with the ASTM data sheet.The analysis of XRD-pattern showed that the high phase Hg-1223 was predominated in the crystal structure of all compound (CuB C C ) and (SnB C C ). The XRD-pattern with the aid of a computer software to determine the lattice parameters. The lattice parameters for Hg-1223 were a=3.99 , b=3.99  and c=16.47 , the compound Cu-1223 had a=4.171 , b=4.171  and c=16.743  and the compound Sn-1223 had a=4.05  , b=4.05  and c=15.682 .The EDX analysis for all compounds was investigated to show the elemental ratio in the mixture in agreement with the applied concentration of elements. The SEM analysis for all ceramic samples were showed the surface morphology and then the nature of grains and their size. The Iodiometric Titration Method also had been used to show the oxygen excess that was the role to enhance the mechanism of superconductivity.The resistivity measurement plays an important role in proving the predominate phase and the superconductor behavior through the presence of critical temperature which was about 115 K, 128 K and 110 K for superconductor compounds Hg-1223, Cu-1223 and Sn-1223 respectively. In order to remove the low phase Cu-1212 appearance in the crystal structure of the high temperature superconductor compound Cu-1223 and to improve the superconductor properties we repeated the sintering process. As a result the XRD analysis indicated that the low phase Cu-1212 predominated in the crystal structure which was had tetragonal phase with the lattice parameters a=3.55  , b=3.55  and c=12.37 . The resistivity measurement was supported the low phase Cu-1212 with critical temperature about 64 K.The main problem is the replacing of Hg atom by covalent atoms such as (Cu,Sn) atoms in the compound ((H )B C C ) by consider (x=0-1). Firstly, the high temperature superconductor of (HgB C C ) Hg-1223 had been synthesized experimentally by solid state reaction. The high temperature superconductor (CuB C C ) Cu-1223, (SnB C C ) Sn-1223 had been synthesized by solid state reaction.There are many parameters affected the preparation technique such as flow of oxygen, sintering temperature and compacted pressure. The ceramic samples of((HgB C C ),(CuB C C ) and (SnB C C ) was analyzed by XRD technique to show the phase of Hg-1223. The XRD-pattern exhibited the presence of Hg-1223, Cu-1223 and Sn-1223 like tetragonal phase incomparable with the ASTM data sheet.The analysis of XRD-pattern showed that the high phase Hg-1223 was predominated in the crystal structure of all compound (CuB C C ) and (SnB C C ). The XRD-pattern with the aid of a computer software to determine the lattice parameters. The lattice parameters for Hg-1223 were a=3.99 , b=3.99  and c=16.47 , the compound Cu-1223 had a=4.171 , b=4.171  and c=16.743  and the compound Sn-1223 had a=4.05  , b=4.05  and c=15.682 . The EDX analysis for all compounds was investigated to show the elemental ratio in the mixture in agreement with the applied concentration of elements. The SEM analysis for all ceramic samples were showed the surface morphology and then the nature of grains and their size. The Iodiometric Titration Method also had been used to show the oxygen excess that was the role to enhance the mechanism of superconductivity.The resistivity measurement plays an important role in proving the predominate phase and the superconductor behavior through the presence of critical temperature which was about 115 K, 128 K and 110 K for superconductor compounds Hg-1223, Cu-1223 and Sn-1223 respectively. In order to remove the low phase Cu-1212 appearance in the crystal structure of the high temperature superconductor compound Cu-1223 and to improve the superconductor properties we repeated the sintering process. As a result the XRD analysis indicated that the low phase Cu-1212 predominated in the crystal structure which was had tetragonal phase with the lattice parameters a=3.55  , b=3.55  and c=12.37 . The resistivity measurement was supported the low phase Cu-1212 with critical temperature about 64 K.