The FALCON double-detector Laue diffractometer add-on for grain mapping at POLDI

Abstract

Laue 3D neutron diffraction tomography (Laue 3DNDT) is a novel tomographic approach that enables non-destructive resolution of the 3D microstructure of polycrystalline materials, utilizing a high-intensity white beam of neutrons, resulting in high experimental efficiency. This article describes the functionality of the fast-acquisition Laue camera for neutrons (FALCON), a double-detector system setup used for Laue 3DNDT experiments at the pulse-overlap diffractometer (POLDI) at the SINQ neutron source of the Paul Scherrer Institute. The reported commissioning includes standard experimental protocols, strategies for acquiring data and a detailed characterization of the measurement system. Finally, single-crystal measurements for calibration and a full grain map of a CoNiGa oligocrystalline sample, extracted from a pilot study, are presented. A detailed understanding of the performance of the FALCON instrumentation is vital for the future advancement of the Laue 3DNDT algorithm, including, but not limited to, improved morphology reconstructions and strain mapping.