The Influence of Thermal Aging on the Mechanical Properties of Electromagnetic Wire for Transformer

In order to study whether the temperature and corrosive sulfur affect the mechanical properties of the electromagnetic wire under long-term normal operation conditions, and then cause the change of the transformer's ability to withstand short-circuit, this paper conducts the low-temperature aging test of CTC conductors and the mechanical performance test of copper wire after sulfur corrosion. After acting on the CTC conductors at different times, the flexural strength test was carried out, and it was obtained that the mechanical properties of epoxy self-adhesive paint did not decrease due to the increase of thermal aging time in the normal operating temperature range of the transformer of the CTC conductors; after the measurement of the copper wire is 220°C and below, the yield strength Rp0.2 of the copper wire does not show an obvious decreasing (annealing effect), by carrying out 300ppm DBDS, 220°C, 72h corrosion sample preparation after the test, the yield strength of copper wire did not show a significant downward trend. In this paper, it can be concluded that the mechanical properties of CTC conductors are basically not affected by thermal aging, that is, the length of temperature action time under the normal operation condition of transformer.