Experimental and numerical study of the running-in wear coefficient during dry sliding contact

The steady-state performance of a tribo-pair is influenced, to a great extent, by the operating conditions at which it is run-in. To gain insight into the influence of operating conditions, experiments are conducted using a pin-on-disk test rig to evaluate the running-in duration under a combination of different loads and speeds. The wear rate and the arithmetic average of asperity heights, R a , and friction coefficient are measured during the running-in period. It is shown that the transient behavior during the running-in period is significantly influenced by the loading condition. At the onset of the steady-state period, the surface roughness, the wear coefficient, and friction coefficient reach a plateau. However, the steady-state friction and wear behavior is influenced by the transient history associated with the running-in period. A predictive model is developed that utilizes the principles of the continuum damage mechanics (CDM) to predict the wear coefficient for transient and steady regimes. Comparisons of the measured wear coefficient and the calculated wear coefficient show acceptable agreement.