Influence of surface roughness on computed tomography dimensional measurements

Abstract X-ray computed tomography (CT) is increasingly used in dimensional metrology. However, several influencing factors affect CT dimensional measurements. In particular, significant deviations can be observed between CT and tactile measurements especially when measuring parts with rough surfaces. The dependence of such deviations from surface morphology has not been thoroughly studied yet. In this work, the influence of surface roughness on CT dimensional measurements is investigated considering the combined effect of surface morphology and CT measurement characteristics. Experimental investigations and numerical simulations are used to determine the systematic effect on CT dimensional measurements for roughness profiles with different material distribution.