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PYXIS, a software package based on the MATLAB platform, is suitable for the in‐depth analysis of synchrotron X‐ray Laue micro/nanodiffraction and energy scan data. The main objective of the software is to analyze the following three aspects of the data. First, in a single Laue diffraction pattern, it can remove the background, search and index the peaks, and obtain the crystal orientation and the elastic strain tensor. A novel zone‐axis assisted indexing algorithm has been developed to speed up this process. Second, a batch of Laue patterns obtained from a scan can be analyzed simultaneously to map the orientation and strain distributions, which is achieved efficiently by applying a peak position comparison strategy. An analysis of a Laue microdiffraction scan of the cross section of Li7La3Zr2O12 solid‐state electrolyte has been taken as an example in this article to illustrate these functions. The third unique function in PYXIS involves data mining of energy scans. Considering a Ni‐based superalloy as an example, the energy scan data sets are processed to reconstruct the diffraction peaks in three dimensions, allowing extraction of the lattice constants, lattice misfit and dislocation characteristics from the peak profiles. [ABSTRACT FROM AUTHOR]

The effects of grain boundaries (GBs) on the initiation of hydrogen-induced blisters in pure iron were investigated using synchrotron polychromatic X-ray Laue nano-diffraction. It was found that the random GBs were more susceptible to blistering than the coincidence site lattice grain boundaries. High strain levels and severe plastic deformation were observed around the random GBs after hydrogen charging, but not on the coincidence site lattice grain boundaries. Unlabelled Image [ABSTRACT FROM AUTHOR]

[Display omitted] • Redundant dislocations are revealed to play a dominant role in laser shock peening induced plastic deformation in Ni-based superalloys. • Local dislocation densities in γ and γʹ phases are quantified separately using µXRD in a laser shock peened Ni-based superalloy. • A quantitative relationship between micro-scale local hardness increment and dislocation density is established over a millimeter range. Laser shock peening (LSP), a surface modification technique, is promising to enhance the strength and wear resistance for Ni-based superalloys. To understand the strengthening mechanism in a laser shock peened Ni-based superalloy DZ417G, we utilize synchrotron poly- and monochromatic X-ray microdiffraction, as well as electron microscopy and microhardness to quantify the local microstructures and mechanical properties at various depths. In the 1.2-mm-deep hardened layer, the microhardness increases monotonically by ∼50% from the unaffected interior to the surface. Quantitative microdiffraction analysis shows that large amounts of dislocations are introduced by LSP. High densities of 7.1 × 1015 m−2 and 11.8 × 1015 m−2 are seen close to the peened surface for the γ- and γ′-phases, respectively, which are 5 and 20 times of those in the unaffected region. Different gradients of dislocation density are observed for the two phases from interior to surface, and their combined effect accounts well for the hardness increment. Due to the unaltered γ′-precipitates and chemical composition in the LSP affected zone, the large density of dislocations dominates the observed strengthening. Combined poly- and monochromatic X-ray microdiffraction allows quantifying the local microstructures of plastic deformation over a large sampling scale that can hardly be achieved using other materials characterization techniques. [ABSTRACT FROM AUTHOR]