Surface as a carrier of information about the tribological process

Production processes and the processes of wear leave their fingerprints on the surface texture of machine components. Therefore, surface texture is, without a doubt, a carrier of information about these processes. The specialized analysis of surface texture can deliver much useful information about the changes of the surface that occurred during tribological processes as well as information about the phenomena occurring during these processes. This paper presents the kind of analysis done on the basis of the piston skirt surface texture after engine operating conditions. This important engine element was chosen as an object of research since, according to the literature review, the analysis of this surface type is complicated because the base (valley) structure has a deterministic character, but the plateau structure - a random one. The approach presented in the paper gives the possibility to obtain information about changes of particular surface texture layers, thus providing such information as the initial height of the original profile (before wear) and the standard deviation of the plateau part of the surface of the piston skirt. The impact of wear processes on the participation of the particular components of the surface texture is also pointed out. On the basis of the information derived from the model, the method of estimation of local linear wear of the piston skirt is introduced. The possibilities of this approach are presented and discussed as well as a critical analysis of the results.