Determination of fundamental parameters for the cross-hatched cylinder liner micro-geometry

This paper is part of a project aiming at optimizing the cylinder-liner/piston-ring contact performance: oil consumption, friction and wear. The surface micro-geometry has a major influence on these characteristics. Classical cylinder-liners display cross-hatched patterns. Grooves modify contact pressure distributions and act as lubricant reservoirs and pipes redistributing oil. The load-carrying capacity is greatly influenced by the number of grooves and their geometry. An automatic groove geometry identification (depth, width, angle) is performed on cylinder-liner surface measurements. The surfaces were measured at two instants: new and after a fired engine test. The micro-geometry evolution is discussed.