Abstract
Superconductivity and structure of YBCO with added WO3 have been investigated. The result indicates that the addition of up to 5% WO3 does not destroy the superconducting properties of YBCO. It is found that the samples with the WO3 addition directly quenched from 900 degrees C in an oxygen atmosphere have a transition temperature of 88 K. The tetragonal-to-orthorhombic transformation takes place within a short time in the YBCO-WO3 samples. Extra peaks can be observed in the x-ray diffraction pattern, indicating that there is a second phase in the samples.