Relaxation of internal stresses in composite second-generation high-temperature superconductors by means of high energy ion irradiation

Abstract

In order to remove internal stresses in composite 2-G YBCO(123) high-temperature superconductors (HTS), they are irradiated with 40Ar8+ ions with an energy of 48 MeV or 84Kr17+ ions with an energy of 107 MeV and a fluence of (1–2) ×1010 ion/cm2. Growth stresses in samples have been studied by scanning electron microscopy and X-ray diffraction analysis. It has been found that initial samples contain significant internal stresses, which, over the course of time, lead to the destruction of the superconducting layer. These stresses disappear after ion irradiation in the regimes specified. Possible mechanisms of stress relaxation are discussed.