EFFECTS OF SURFACE PREPARATION ON FRICTION AND WEAR IN DRY SLIDING CONDITIONS

摘要

Wear tests were conducted using a ball-on-disc tester T-11. In the experiment, a 42CrMo4 rotating steel disc with a hardness of 40±2 HRC was placed in contact with a 100Cr6 steel ball with a diameter of 6.35 [mm]. The hardness of the ball was set to 62±2 HRC. Finishing treatment applied to the surfaces was sand blasting. Disc samples were prepared to obtain surfaces in similar range of the Sa parameter (arithmetical mean height of the surface) but other surface topography parameters vary. Dry sliding tests were conducted at sliding speeds of v_1 = 0.16; v_2 = 0.24 i v_3 = 0.32 [m/s]. The sliding distance was set to 282.6 [m], and the normal load was set to 9.81 [N]. During the tests, the friction force was monitored as a function of time. Disc and ball wear was measured after the tests using a white light interferometer Talysurf CCI Lite. Profiles were taken in four positions (900 apart) perpendicular to the wear track. Then, using an interferometer software program TalyMap Gold 6.0, they were computed and averaged. It was found that the initial surface topography has a significant influence on friction and wear levels under dry sliding conditions. It was also identified the correlation between several surface topography parameters and wear volume.