Design and manufacturing aspects of gauges for Detail Detection Sensitivity monitoring in industrial X-ray CT

Indrustrial X-ray Computed Tomography (iCT) is increasingly being used in dimensional metrology and non-destructive testing (NDT).It is particularly valuable in high-value and safety-critical manufacturing, where complex internal geometry and/or material combinations can prevent the use of classical measurement methods.However, some challenges still limit its widespread use.It can be difficult to establish measurement traceability, as well as to determine detectability limits of internal flaws or geometrical features.As XiCT is stemming from the NDT field, decades of experience and data is available on visual inspection and limits of detectability of flaws by human operators.Detail Detection Sensitivity (DDS) is a parameter used to quantify this limit, using the size of the smallest visually detectable hole in an Image Quality Indicator (IQI) as a limit of detectability.The new ASTM standard E3505 as well as the EURAMET project "SensMonCT II" (JRP 23NRM05) aims to develop new test gauges which will be optimised for the determination of the DDS of iCT systems.Different design aspects of the proposed gauges as well as different manufacturing methods are described in this paper.We will show first results of manufactured gauges conforming to the new ASTM E3505-25 standard on DDS and take a look at how to ensure traceability of the gauges for quality assurance.