Abstract: The current-carrying frictional pair composed of inner raceway， outer raceway，and flexible ring is the conductive core component of the space rotating electrical transmission mechanism. To investigate the effect of vacuum temperature on the transmission performance of flexible rings， rolling current-carrying tribological tests were carried out in the temperature range of -30℃~120℃ in 1×10^-3Pa vacuum. As the temperature increased from -30℃ to 120℃，the steady-state average friction force decreased from 3.96N to 1.48N， and the elastic force decreased from 6.8N to 5.9N. There was no significant change in the average contact resistance and wear amount. Microscopic morphology showed that the wear width increased from 47.37μm to 66.71μm， the roughness of the worn area dropped from 0.45μm to 0.25μm.The extrusion deformation caused by high-temperature softening of materials should be the main reason for the widening of wear marks.Material softening and its concomitant widening of wear marks lead to a decline in the elastic force of the flexible ring.

Key words: temperature, wear width, rolling current-carrying tribology, soften, vacuum