High‐Resolution Microfocus X‐Ray Computed Tomography for 3D Surface Roughness Measurements of Additive Manufactured Porous Materials

Since commercially available profiling systems fail when determining the surface roughness of porous materials, we propose a novel protocol for surface roughness quantification of 3D additive manufactured porous structures based on high‐resolution microfocus X‐ray computed tomography (micro‐CT) images. It allows to non‐destructively assess the roughness of these porous materials at the outer surface as well as inside the structure. The noise in the images and the spatial image resolution both have a significant effect on the accuracy of the micro‐CT‐based roughness measurements. Comparing the roughness parameters of flat substrates determined both with commercially available (optical and contact) profiling systems and the micro‐CT‐based roughness measurement protocol shows that micro‐CT can be applied accurately and in a robust manner for surface roughness quantification of 3D additive manufactured porous materials with a micro‐scale roughness. Depending on the dimensions of the roughness, the micro‐CT acquisition parameters, i.e., frame averaging and spatial image resolution, need to be fine‐tuned. Submicron‐scale roughness can currently not be quantified.