Production of non-stoichiometric YBCO powder with high oxygen content by self-combustion sol gel method for the production of SQUID sensors

The nonstoichiometric composition of YBCO is due to the superconducting temperature and the desired critical current density for a wide range of uses, including the use of highly sensitive SQUID sensors. But its superconducting properties are subject to severe changes with the oxygen index and purity of the composition. The properties and superconductivity temperature of the compound are related to producing pure and homogeneous with a precise ratio of this non-stoichiometric compound in phase Y: 123. In this study, the production of this high-temperature superconductor was carried out using a self-combustion sol-gel process with nitrate forming elements. The phase Y: 123 was prepared at annealing temperature of 940 ° C with suitable purity. In these conditions, the superconducting phase Y: 123 was produced and the impurities were removed and on the other hand, the need for further thermal treatment and the costly annealing process were removed. The optimum conditions for the production of Y: 123 superconducting powder were obtained by sol gel self-combustion method. Finally, optimal conditions for deposition of this compound on the substrate for producing the SQUID sensor were investigated and an optimal condition was presented.

Keywords:

High temperature super conductor , SQUID , YBCO , STO , sol gel self-combustion