Optical Topography Measurement and Material Characterisation of Alu Cylinder Walls

Surface topography characterisation of engine cylinder walls using optical methods such as microscopic stripe projection, white light interferometry (WLI) and micro ellipsometry is outlined. Both the surface topography and also the kind of material can be measured, in especially the Si particle size and location distribution and the overall profile amplitude distribution. In case of an iron coated aluminium matrix a simple method is described to quickly check the equal roughening of the surface and the pore size distribution. The measurement result decides whether rework is necessary before the time consuming and expensive spraying process is performed.