The demands on decreased environmental impact from vehicles are resulting in a strong push for decreased engine oil and fuel consumption.

Recent engine tests have shown a promising reduction in oil consumption when using cylinder liners with a smoother finish than the current plateau honing.

One approach to produce smoother liner surfaces is to replace SiC ceramic honing stones with diamond tools. However, even though the diamond honing process results in higher productivity, improved quality control is needed to monitor the degree of cold worked material - “blechmantel” (German), and the resulting risk of increased wear and scuffing.

A number of petrol and diesel engine cylinder liners have been mapped to be able to verify the quality and consequences, in terms of wear and function, of the honing process. A new mapping method, combining SEM images and quantitative image analysis with traditional 2D profilometry has been developed and tested in this study. The surface mapping method developed was employed before and after the test to study effect of running-in wear on the surface, features characterized with the SEM- and the 2D profilometer.

The results show that combining SEM- and profilometric methods gives a good picture of the effects of varying the cylinder liner pressure and roughness. The core roughness decreases more for diesel liners than for petrol liners.. A probable cause is that the more severe diesel high pressure run-in conditions are able to effectively “truncate” the plateaux and remove residing plastically deformed un-cut honing residues while the less severe petrol liner conditions do not manage to remove the blechmantel and irregularities to an important extent.