X-ray computed tomography for metal additive manufacturing: Challenges and solutions for accuracy enhancement

Additively manufactured parts are characterized by metrological challenges and complexities, due to several reasons, including the inherent presence of internal defects and complex surface topography. Micro X-ray computed tomography is currently used to perform dimensional evaluations, porosity analysis and, more recently, surface topography measurements of additively manufactured parts thanks to the possibility of analysing non-destructively also non-accessible geometries and micro-scale features. However, the accuracy of these evaluations can be limited due to the high complexity of such parts. This work summarizes the results of experimental investigations on metrological challenges and accuracy of tomographic analyses, based on studies performed on Ti6Al4V specimens produced via selective laser melting.