On the Modeling of Adhesive Wear with Consideration of Loading Sequence

Established models for predicting adhesive wear in sliding tribo-systems are based on the assumption that applied load remains constant. However, in many applications, load rarely remains constant—changing from low-to-high and high-to-low, or always fluctuating. Hence, the applicability of the existing wear models for prediction purposes becomes questionable. In the present work, an attempt is made to develop a wear model using the principles of thermodynamics to address this drawback. The proposed wear model establishes a relationship between the so-called degradation coefficient, load-dependent friction force, and the contact temperature. Efficacy of the proposed wear model is demonstrated by considering four cases of published data with variable loading sequence as well as additional series of ball-on-disk experiments conducted as a part of this study to validate the theory. A detailed explanation is provided to illustrate how a constant degradation coefficient value could predict the cumulative wear volume in applications dealing with variable loading while the Archard wear coefficient could not.