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X‐ray diffractometers primarily designed for surface X‐ray diffraction are often used to measure the diffraction from powders, textured materials and fiber‐texture samples in 2gθ scans. Unlike in high‐energy powder diffraction, only a fraction of the powder rings is typically measured, and the data consist of many detector images across the 2gθ range. Such diffractometers typically scan in directions not possible on a conventional laboratory diffractometer, which gives enhanced control of the scattering vector relative to the sample orientation. There are, however, very few examples where the measured intensity is directly used, such as for profile/Rietveld refinement, as is common with other powder diffraction data. Although the underlying physics is known, converting the data is time consuming and the appropriate corrections are dispersed across several publications, often not with powder diffraction in mind. This paper presents the angle calculations and correction factors required to calculate meaningful intensities for 2gθ scans with a (2 + 3)‐type diffractometer and an area detector. Some of the limitations with respect to texture, refraction and instrumental resolution are also discussed, as is the kind of information that one can hope to obtain. [ABSTRACT FROM AUTHOR]

The CO 2 corrosion-induced scale developed in the surface region of the low-grade carbon steel is thoroughly investigated to understand the corrosion mechanisms involved during exposure to CO 2 -saturated aqueous environments. In this work, in addition to the electron microscopy and lab-source X-ray diffraction (XRD) methods, ex-situ depth-resolved phase identification of the corrosion scales developed on steel with different initial microstructures is performed using synchrotron grazing incidence XRD at different incidence angles. The CO 2 corrosion mechanism is discussed considering the observed distribution of the corrosion products formed at a different depth relative to the time of electrochemical exposure of the steels. [Display omitted] • Mode of corrosion propagation affects scale composition, distribution & morphology. • Corrosion scale morphology depends on the initial steel microstructure. • Variation in local pH atop different micro-regions forms differential scale. • Higher local pH within cementite lamellas accelerates mixed carbonate precipitation. • Vertical interfaces in corrosion scale causes higher ionic permeability. [ABSTRACT FROM AUTHOR]