A uranium-molybdenum alloy clad in 6061 aluminum has the potential to lead to a wide application of low-enriched uranium fuels, replacing highly enriched uranium for research reactors. A Zr coating acts as a diffusion barrier between the fuel and the aluminum cladding. In this study, U-10Mo (mass %) was coated with Zr using a plasma spray technique recognized as a fast and economical coating method. Neutron time-of-flight diffraction was used to study the microstructure evolution by quantifying

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... the phase fractions of involved phases as well as the texture evolution of U-10Mo and Zr during plasma spray coating with Zr. Quantitative texture analysis revealed that the texture was drastically changed for high coating temperatures, likely due to selective grain growth. Furthermore, the Zr coating showed a preferential orientation, which could be correlated with the initial texture of the uncoated U-10Mo. This could be explained by the epitaxial growth of the Zr on the U-10Mo substrate. Quantum Beam Sci. 2018, 2, 12 2 of 11 microstructure evolution of the fuel material is under research, and the physical properties [4-7] as well as the crystallographic phases [3, 4, 6, 8] , including the time-temperature-transformation (TTT) diagram [9,10], have been investigated by diffraction methods, few studies of microstructural changes, such as texture evolution, resulting from other fuel fabrication process steps are known. These may also cause anisotropy in material properties and therefore require attention. Furthermore, U-Mo fuel foils will be clad in 6061 aluminum. In order to prevent interaction between the fuel meat and the cladding, a zirconium metal diffusion barrier will be applied to the fuel prior to cladding [1, [11] [12] [13] . Hot roll bonding, electroplating, and plasma spraying [14] after cold rolling have been studied to apply the Zr layer on the U-10Mo (mass %)-referred to as U-10Mo in the following. However, only recently has the bulk microstructure evolution of the U-10Mo foil during spray-coating, which should be studied for a better understanding of the anisotropic behavior of the material, been investigated [15] . The objective of this study, therefore, is to understand the texture evolution in U-10Mo nuclear fuel foils during plasma spray coating with Zr by means of a detailed component analysis of the orientation distribution function (ODF) of the observed textures. While pole figures are frequently used to represent textures, quantitative analysis of the ODF, such as the determination of volume fractions of fibers and components, provides a much more complete picture of the microstructure evolution [16] [17] [18] [19] , as it allows for the prediction of metallurgical phenomena such as the recrystallization of γ phase. The ODF analysis for cubic crystal structures is very well known due to the extensive research on steels [20] [21] [22] . The results of this body of work is applied here to interpret textures in the much less investigated bcc U-10Mo. This report focuses on the texture data; other properties are provided and discussed in another manuscript [15] . Neutrons are an excellent probe for bulk texture measurements of uranium and its alloys, as it probes the entire sample volume, whereas X-ray or electron-based methods at best probe a few micrometers in these materials. Furthermore, full pattern diffraction data analysis utilizing tens of diffraction peaks, including overlapped ones, by Rietveld texture analysis allows for texture analysis of materials when no separate peaks are available to measure individual pole figures.