Study Reveals Impact of Surface Scratches on the Structural Integrity of Superconducting REBCO Tapes

Our colleages at Department of Superconductor at IEE SAS uncovered the significant effects of surface scratches on REBCO (Rare-Earth Barium Copper Oxide) superconducting tapes. These tapes, widely used in high-temperature superconductor (HTS) applications, face substantial mechanical stress during manufacturing and operation. The study, published in Physica C, reveals how even minor surface damage can lead to structural failure when these tapes are bent.

The research team investigated REBCO-coated tapes with surface scratches on their silver coating, a result of the manufacturing process. By bending the tapes at various diameters, the scientists discovered that delamination in the REBCO layer consistently initiated at scratched points, especially when bent at diameters smaller than 7 mm. Using scanning electron microscopy (SEM), the team captured detailed images showing delamination and critical current reductions—a clear indicator of reduced superconducting capacity.

The study found that bending the scratched tapes at diameters below 5 mm caused widespread delamination, compromising the material’s ability to carry high currents. Our findings highlight the need for strict quality control during production. Even minor surface scratches can significantly reduce the lifespan and reliability of REBCO tapes in high-stress applications.

This research provides valuable insights for industries utilizing HTS technology in applications like MRI machines and power cables. By improving production processes to minimize scratches, manufacturers can enhance the durability of REBCO tapes, ensuring consistent superconducting performance even under challenging conditions.

Link:  https://doi.org/10.1016/j.physc.2023.1354358

Authors: R. Ries, D. Hlaváč, M. Solovyov, F. Gömöry