A literature review was carried out to assess the current state of the art practices for standard reference geometries and IQIs for all radiographic techniques. The review findings were used to design three new geometries for further consideration and development.
Taking into account these findings, and the requirements from ESA, the potential geometries were subjected to a set of weighted evaluation criteria, which resulted in the final design (Figure 1).
The final design is based around a step cylinder comprised of aluminium, with removable internal cylindrical pins that are raised within the part to represent different penetrable thicknesses. In order to assess the image quality, micrometre scale line features were placed in a circular pattern around the removable pins along with hemispherical patterns to represent porosity. Figure 2 shows an XCT image of the manufactured step cylinder.
This design offers a flexible platform for expansion and adjustment in terms of size, resolution and material. The modular design will allow the investigation of image quality for various penetration pathways of the XCT system as well as for multi-material components.