Abstract:In order to reveal the wear and corrosion characteristics of metal materials under torsional contact in liquid medium at constant temperature, a new device for torsional wear corrosion test was developed. Using the test system, torsional wear corrosion tests of Ti6Al4V were carried out in saline solution at 37℃ under a normal load of 50 N, a torsional angular displacement amplitude of ±3°, and a frequency of 0.5 Hz. The results showed that the friction torque curves of the Ti6Al4V alloy in saline solution could be divided four stages: the friction torque was very low at first; it increased gradually to a peak value; after the peak, it decreased slightly; and then increased gradually to a relatively stable value at last. Three types of torques vs angular displacement curves in shapes of line, elliptical, and quasi-parallelogram presented during the tests. At the beginning of torsion, the free corrosion potential of the Ti6Al4V alloy had a rapid negative shift, followed by a slow positive shift to a relatively stable value lower than before torsion. Simultaneously, the corrosion current increased rapidly and then decreased to a relatively stable value higher than before torsion. The damage of Ti6Al4V alloy was typically caused by coupled wear and corrosion.