Comprehensive analysis of surfaces featuring functional characteristics by angular resolved scattering light measurement

Traditional surface metrology mainly focuses on measuring distances between the sensor and the workpiece to gain insights into the geometric properties of the workpiece. Surface texture parameters however may not always offer a comprehensive understanding of a surface's functional aspects. For certain applications that require highly sensitive process monitoring, the distribution of the surface gradient can serve as a crucial measure. The presented study aims to establish a direct correlation between the angular resolved scattering light distribution and the functional characteristics of surfaces. A direct measurement of the angular distribution does not exhibit the potential deviations that occur during the numerical derivation of measured topography data. While the sensor principle is commonly used for process monitoring, the relationship between the angular distribution and functional characteristics like wear, friction, and lubrication has not been widely described. We compare topography measurements and associated surface texture parameters with information derived from angular resolved scattering light measurements. Cylinder liner surfaces serve as a case study.