Abstract
High purity Ti3AlC2 samples were prepared by an infiltration sintering method. The current carrying friction and wear characteristics of high pure bulk Ti3AlC2 dry sliding against a GCr15 bearing steel disc were experimentally investigated on a pin-on-disk type tester at several sliding speeds from 20 to 60 m s−1, different electric currents from 0 to 100 A and normal pressures from 0·1 to 0·6 MPa. It was found that the highly pure Ti3AlC2 exhibits an increasing friction coefficient (0·11–0·65) and an increasing wear rate (2·13–7·75×10−6 mm3 N−1 m−1) with the electric current increasing from 0 to 100 A; the normal pressure (0·1–0·6 MPa) and the sliding speed (20–60 m s−1) also have a complex but relatively weak influence on them. The minimum value of friction coefficient was 0·11 when the sliding electric current, speed and normal pressure were set to 0 A, 60 m s−1 and 0·6 MPa; the wear rate reached the maximum value 7·75×10−6 mm3 N−1 m −1 when the sliding electric current, speed and normal pressure respectively were set to 100 A, 60 m s−1 and 0·6 MPa. The low friction coefficient can be attributed to the presence of a continuous frictional oxide film consisting of an amorphous mixture of Al, Ti and Fe oxides on the friction surface, which have a significant antifriction effect on the friction surfaces. The percentage of oxide film cover was relatively higher when the electric current was 0 A, while the percentage of oxide film cover decreased with increasing electric current. The increase in the wear rate was ascribed to the ablation of the electric arc when the electric current was high.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call