Role of Tungsten Oxide in enhancing superconducting and mechanical properties of YBa2Cu3O7-δ

Abstract

The practical application of high temperature superconductors require a quite higher value of critical current density Jc, which is mandatory towards practical fields like superconducting magnetic sensors, superconducting wires, tapes etc. To have a sustainable practical applications like magnetic bearing and magnetic shields, etc. the variation of elastic parameters of the composite materials require attention. To achieve some of the properties as above the nanocomposite of (1-x) YBa2Cu3O7-δ / x (WO3) was synthesized by standard solid state reaction technique. The structural and surface morphology of the sample was examined through X-ray diffraction and Field emission scanning electron microscopy respectively. The superconducting transition temperature was confirmed from the self-field transport measurement. Various superconducting parameters obtained from the transport analysis were discussed. The electric field versus current density curve showed the enhancement of critical current density (JC) due to the addition of WO3 nanoparticles. This may be attributed to better connectivity between the superconducting grains resulting in an increase of superconducting volume fraction of the samples. Furthermore, to study the variation of elastic parameters of the composite samples, the ultrasonic pulse-echo technique was utilized. The ultrasonic velocities are increased with increasing wt. % of WO3 additives. Simultaneously, the Longitudinal Modulus (L), Modulus of Rigidity (G), and Young’s Modulus (Y) are also increased with increasing wt. % of WO3. It may be due to the opposition developed by the WO3 additives towards the dislocation motion between the superconducting grains, as such additives reside near the grain boundary regions.