Nowadays, 2G HTSC tapes are used in many industrial applications: motors, generators, current limiters, power cables, transformers. The duration of the reliable and stable operation of these devices is determined by the properties of the HTSC tapes on the basis of which they are designed. One of the known problems of HTS operation is the appearance of irreversible local changes in the structure due to prolonged flow of electric current, which can lead to a deterioration in the current-carrying ability.

In this work, that phenomenon in industrial samples of 2G HTSC tapes was investigated. Copper-coated YBaCuO tapes produced by SuperOx were used as samples. A superconducting bridge was previously formed on the surface of the tape by chemical etching. A direct current of I=0.9Ic was passed through the sample. The duration of exposure was about 100 hours. The current density in the area of the bridge was about 10^5A/cm^2. The measurements were carried out at liquid nitrogen temperature (77 K). The influence of the electric current flow on the Ic value of the sample after 1, 10 and 100 hours of exposure is evaluated by means of the I – V characteristic. A comparison between a control sample at room temperature, a sample at the temperature of liquid nitrogen not subjected to current flow stress and sample exposed to current flow was made.