Variances in cylinder bore surface finish influence oil consumption, wear, and scuffing. Recently published studies indicate oil consumption is a significant contributor to pre-ignition in small high power density engines and natural gas engines. Implementation of a three dimensional Surface Finish Analysis System to quantify the honed surface provides multiple benefits in engine development. The resultant improved cylinder bore surface can be utilized to minimize development time.
Three Dimensional surface finish analyses provide higher quality surface finish data permitting fewer measurements with increased statistical confidence when compared to the historic industry standard, Two Dimensional Profilometer finish data. The three dimensional analysis systems build on the advantages already established by a Volvo, Mercedes, and Volkswagen 14-year program. The three dimensional system utilizes this foundation to create an improved cylinder bore surface finish analysis system utilizing a unique, nondestructive, replicate method and advanced software system. The replicating method has exceptional repeatability and demonstrates no statistical difference from the destructive, direct imaging approach, while covering the whole ring travel as opposed to the ∼3-10 mm of a Two Dimensional Profilometer.
The three dimensional surface finish analyses offer additional unique features not possible with a Two Dimensional Profilometer. Torn and Folded Material, cross hatch angle and porosity in addition to surface finish can be quantified. Porosity and its effect on two dimensional finish values are important as the number of spray coated cylinder bores increase.