Experimental investigations on the accuracy of X-ray computed tomography for porosity measurements of additive manufactured parts

Recent advances in Additive Manufacturing (AM) have shown a great potential in production of intricate structures due to its almost unlimited design freedom even for internal features. However, inherent imperfections such as internal porosity arise from the AM process. As these internal defects cannot be completely removed, knowing the information about the defects shape, size and distribution becomes crucial. Recently, X-ray computed tomography (CT) has emerged as an advanced tool for internal defects measurement; however, the errors of CT porosity measurements have not yet been thoroughly quantified. In this work, in a first step, CT porosity analysis conducted on Ti6Al4V specimens produced by AM is compared to results by Archimedes method, microscopic analysis and multisensor CMM. In a second step, a newly developed reference object is used for evaluating errors of CT porosity measurements.