Influence of geometric defects on the compression behaviour of thin shell lattices fabricated by micro laser powder bed fusion

Lifton, Joseph and Feih, Stefanie (2022) Influence of geometric defects on the compression behaviour of thin shell lattices fabricated by micro laser powder bed fusion. Additive Manufacturing, 58, [103038]. (doi:10.1016/j.addma.2022.103038).

Abstract

X-ray computed tomography (XCT) is a promising tool for making dimensional measurements of complex engineering components. The adoption of XCT as a measurement tool is hindered by the inability to evaluate the uncertainty of XCT-based dimensional measurements; simply put, XCT users cannot specify how good (or bad) their measurements are. In this work, equations and a method are given to evaluate the standard uncertainty due to the voxel size; this being one of several sources of uncertainty in XCT-based dimensional measurements. It is envisioned that this standard uncertainty component will be combined with other standard uncertainties in a task-specific uncertainty budget, thus providing end users with a statement of XCT measurement uncertainty. It is claimed here that evaluating the standard uncertainty of the voxel size by means of a calibrated length leads to a traceable voxel size. For the example considered in this work, the voxel size is evaluated to be 80.005 μm ± 0.001 μm, with the voxel size uncertainty expressed as one standard deviation. When the standard uncertainty of the voxel size is propagated through to the final measurement result of a machined aluminium length bar, the standard uncertainty due to the voxel size is evaluated as ± 1.01 μm for a bi-directional length of nominally 55 mm.

This record has no associated files available for download.

Contributors

Author: Joseph Lifton

Download statistics