Published online by Cambridge University Press: 18 March 2011
Resistive superconducting (SC) transition, current-voltage characteristics, and X-ray diffraction (XRD) of YBaCuO ceramics have been studied after exposure to 18 MeV proton beam at 300 K. In the interval of 1013 −5×1014 cm−2 the irradiation induced oxygenation of weak intergrain contacts and grain alignment, anisotropy and broadening of SC-transition measured along and across the proton beam, and residual magnetization were found. The proton induced anisotropic texture is responsible for the critical current increase at 77 K and the resistivity decrease at 90–200 K. In a higher dose interval of 1013 −1015 cm−2 the SC-transition parameters degrade and the resistivity increases, depending on a texture degree, weak intergrain links become deoxygenated and no texture occurs. The magnetization (pinning) and the anisotropy of SC-transition can be due to localization of charges at the proton induced defects (mostly in oxygen sublattices).