20.500.12556/RUL-188481 X-Ray CT inspection limitations in a thick-walled LPBF hydraulic manifold an industrial case study Metal additive manufacturing (AM) enables compact hydraulic manifolds with curved internal channels, reduced part count and integrated functionality. However, these benefits also create major inspection challenges, especially in thick metallic sections containing closely spaced and intersecting passages. This study examines the practical use of X-ray computed tomography (CT) for an industrial hydraulic manifold manufactured from maraging steel MS1 by laser powder bed fusion (LPBF). Selected cross-sections from the reconstructed CT volume were compared with the nominal computer-aided design (CAD) geometry and evaluated using a qualitative interpretability classification supported by comparative image contrast-to-noise ratio (CNR) analysis and approximate projected steel thicknesses. Clearly interpretable regions showed higher and more consistent CNR, whereas geometrically congested regions generally exhibited lower and more variable local contrast. However, projected material thickness alone did not determine interpretability, indicating an additional influence of geometric overlap, orientation and reconstruction artefacts. Particular attention was given to a channel wall adjacent to a locally collapsed external support structure. No spatially persistent through-wall discontinuity was identified, although smaller defects, local wall thinning and metallurgical changes could not be excluded. A pneumatic immersion test at 0.8 MPa showed no visible bubble formation or observable pressure decrease. This pressure exceeded the expected operating pressure of the affected relief or tank channel but was substantially below the 35 MPa maximum intended pressure of the pressure-side circuits and therefore did not constitute structural qualification. The study demonstrates that whole-component CT can provide useful local inspection information for complex LPBF manifolds, but its reliability depends strongly on local geometry and acquisition conditions. Quantitative image assessment and complementary functional testing may therefore be required when CT results are insufficient for complete qualification. laser powder bed fusion hydraulic manifold X-ray computed tomography non-destructive testing internal channels leak testing lasersko taljenje v prašni postelji hidravlični bloki računalniška tomografija z x-žarki nedestruktivno testiranje notranji kanali testiranje puščanja true false true Angleški jezik Slovenski jezik Članek v reviji 2026-09-23 11:37:04 2026-09-23 11:37:22 2026-09-24 04:25:27 0000-00-00 00:00:00 2026 0 0 19 str. iss. 9, art. 969 Vol. 16 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.386:621.762 2075-4701 10.3390/met16090969 292157699 Bartolj_..._X-Ray_CT_inspection....pdf Bartolj_..._X-Ray_CT_inspection....pdf 1 6F1D6D01173CF42115EDB1CB7B83D8DC 49d3072646d768ae852ea8c114466da3a952a8914d55e662c342134aea94e0e9 8667c148-b732-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=248665 https://www.mdpi.com/2075-4701/16/9/969 1 501e064a-b732-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=248664 Fakulteta za strojništvo 0 0 0