A qualitative empirical model of cylinder bore wear

Designers of internal combustion engines have useful equations for many of the factors influencing reliability and performance, but not for wear. In this investigation, a laboratory simulator was used to identify the important variables influencing cylinder bore wear. The same characteristics of wear were observed in the simulator as in running engines, even though the simulator did not attempt to duplicate all the conditions found within an engine. Data were collected showing the influence of several parameters. In particular, a strong effect from ring material was observed. A new picture of wear in cylinders is presented, consistent with the data and previous work on boundary lubrication. This qualitative model accounts for the evolution of the cylinder running surface in terms of composition and texture changes. The model can be used to determine the relative importance of the many variables that can influence wear behavior, including contributions from lubricant chemistry, material properties, and mechanical loading. (C) 1999 Elsevier Science S.A, All rights reserved.