A 20-cm-long YBCO tape fabricated by the Rolling Assisted Bi-axially Textured Substrate (RABiTS) technique was used to study the quench behavior of a second-generation high-temperature superconductor (HTS). Quench tests of the sample were performed in a conduction cooling condition with a cryocooler. The sample was subjected to a short overcurrent pulse to create normal zones, followed by a longer operating current up to the critical currents of the weaker zones of the tape. Distinctive normal zone propagation was observed for the first time on a YBCO tape. Propagation velocities of 1.4 to 8.3 mm/s were measured, which increase linearly with the current. Stability margins and a minimum propagation current were also observed. One-dimensional thermal modeling showed good agreement with the test results.
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