Investigation on the effect of the test object material on the metrological performances of X-ray computed tomography systems

X-ray computed tomography (XCT) plays a significant role in industrial metrology, supporting the evolution of manufacturing technologies and the developments of advanced application. Indeed, it enables the measurement of a wide range of complex parts, characterized by internal and non-accessible features, micrometric details or free-form surfaces. However, the effect of a number of quantities, which affect the measurement results, limit the diffusion of the technology and need to be investigated. In this work, the effect of the material of the inspected object is analysed. A reference standard, consisting of a hole plate with a specific distribution of the holes, was designed in order to evaluate the influence of the material of the test object on the metrological performances of an industrial XCT system. The indications provided by the current draft of the ISO 10360-11 standard were followed to metrologically characterize the system, testing two hole-plates of different material, manufactured and calibrated for the study, separately and in combination with a ball plate.