Using X-Ray computed tomography for effective porosity characterisation in additively manufactured metallic parts

Abstract

Common microscopy approaches are considered as destructive technologies for porosity characterization in metallic parts for various engineering components. They are not only time consuming, but also causes wastage of materials due to the need of fabricating numerous batches of specimens just for such characterization. However, X-ray computed tomography has recently emerged as a viable technique to evaluate the porosity content in metallic components without the need of physically damaging them on purpose. Therefore, in this study, X-ray computed tomography and conventional 3D optical microscopy cross-section analysis approaches were used to compare the porosity profile obtained in 316L stainless steel additively manufactured using selective laser melting. both X-ray computed tomography and optical microscopy results both consistently show high densification (>99%) and low porosity (<0.7%) levels, suggesting optimum processing parameters were selected for the selective laser melting process. Similarly, the results of pore size, morphology, and distribution also compare well between both techniques. Overall, X-ray computed tomography is proven to be an effective non-destructive technique to assess porosity and defects in additively manufactured parts.