The effects of 107 MeV Kr-84(17+) ion irradiation on YBa2Cu3O7-x-based second-generation coated conductors were investigated using a combination of transmission electron microscopy, diffraction and X-ray energy dispersive spectrometry. Defects 3-5 nm in diameter formed due to irradiation with relatively low fluences (similar to 2 x 10(10) and similar to 6 x 10(10) cm(-2)). Analysis of electron microscopy images and spectrometry data led to the conclusion that radiation defects are voids approximately 3 nm in diameter. Heavy ion irradiation results in the significant enhancement of YBCO/buffer oxides adhesion to the Hastelloy substrate, the reduction of stresses and the formation of a crack-free structure in the YBCO layer. The use of low-dose irradiation enables the critical current to be increased without lowering the transition temperature. (C) 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Melanie Blokesch, Sandrine Stutzmann, David William Adams, Laurie Righi