The crack formation in filaments of multi-filamentary Bi2Sr2Ca2Cu3Ox tapes as function of applied longitudinal strain is visualized by means of magneto-optical imaging. Strain is applied at the desired temperature inside a helium flow cryostat. Cracks form transverse to the current carrying direction of the filaments. Before the tape breaks entirely, all filaments have formed a large number of transverse cracks, spaced with an average crack distance of ≈200 μm. The crack formation is compared with the degradation of the critical current as a function of the applied strain. The critical current degrades already before the first crack is observed. This is explained by the limited number of filaments visible in the experiment.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering