LUBRICATED FRICTION AND WEAR SIMULATION OF MULTI-SCRATCHES IN ASPERITY-ASPERITY CONTACT

Multi-scratch tests of ball-on-ball (3.175 mm diameter 52100 steel) in lubrication were carried out to simulate the friction and wear proces s of the asperity-asperity contact in sliding. The results show that t he friction coefficient increases with the increased scratch number fr om about 0.1 at the 1st scratch to about 0.4 at the 40th scratch. Ther e is no plastic deformation and wear on the contact surface for the Is t scratch. However, friction coefficient rises to 0.15 at the 5th scra tch and abrasive wear occurs in the contact area. Then, with the scrat ch number increased further, the friction coefficient continues to inc rease and the contact surface undergoes different wear stages: plastic smearing (10th scratch), surface flaw initiation (20th scratch), and tensile crack initiation and propagation (40th scratch). (C) 1998 Else vier Science S.A. All rights reserved.