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Microstructure control of in situ metal matrix nanocomposites (MMNCs) poses a barrier to their large-scale production. Here, we interrogate in unprecedented detail the formation mechanisms, morphologies, and microstructures of an in situ Al/TiC MMNC processed via salt flux reaction. Through synchrotron-based X-ray nanotomography (TXM) and scanning and transmission electron microscopy, we visualize in over five orders-of-magnitude of length-scale the TiC nanoparticles, Al_3Ti intermetallics, and their co-locations. 3D reconstructions from TXM revealed a surprising variety of Al_3Ti morphologies, including an orthogonal plate structure. By combining our experimental results with phase-field simulations, we demonstrate that this growth form originates from the intermetallic nucleating epitaxially on a TiC particle which is larger than a critical size at a given undercooling. Yet TiC particles that are too small to nucleate Al_3Ti can also impact the growth of the intermetallic, by splitting the intermetallic plates during solidification. These insights on the divalent roles of the nanoparticles offer general guidelines for the synthesis and processing of MMNCs. 

Image registration is broadly used in various scenarios in which similar scenes in different images are to be aligned. However, image registration becomes challenging when the contrasts and backgrounds in the images are vastly different. This work proposes using the total variation of the difference map between two images (TVDM) as a dissimilarity metric in rigid registration. A method based on TVDM minimization is implemented for image rigid registration. The method is tested with both synthesized and real experimental data that have various noise and background conditions. The performance of the proposed method is compared with the results of other rigid registration methods. It is demonstrated that the proposed method is highly accurate and robust and outperforms other methods in all of the tests. The new algorithm provides a robust option for image registrations that are critical to many nano-scale X-ray imaging and microscopy applications. 

A transmission X-ray microscope (TXM) can investigate morphological and chemical information of a tens to hundred micrometre-thick specimen on a length scale of tens to hundreds of nanometres. It has broad applications in material sciences and battery research. TXM data processing is composed of multiple steps. A workflow software has been developed that integrates all the tools required for general TXM data processing and visualization. The software is written in Python and has a graphic user interface in Jupyter Notebook . Users have access to the intermediate analysis results within Jupyter Notebook and have options to insert extra data processing steps in addition to those that are integrated in the software. The software seamlessly integrates ImageJ as its primary image viewer, providing rich image visualization and processing routines. As a guide for users, several TXM specific data analysis issues and examples are also presented. 

Ni-rich layered oxides as high-capacity battery cathodes suffer from degradation at high voltages. We utilize a dry surface modification method, mechanofusion (MF), to achieve enhanced battery stability. The simplicity, high yield, and flexibility make it cost-effective and highly attractive for processing at the industrial scale. The underlying mechanisms responsible for performance improvement are unveiled by a systematic study combining multiple probes, e.g., 3D nano-tomography, spectroscopic imaging, in situ synchrotron diffraction, and finite element analysis (FEA). MF affects the bulk crystallography by introducing partially disordered structure, microstrain, and local lattice variation. Furthermore, the crack initiation and propagation pattern during delithiation are regulated and the overall mechanical fracture is reduced after such surface coating. We validate that MF can alter the bulk charging pathways. Such a synergic effect between surface modification and bulk charge distribution is fundamentally important for designing next-generation battery cathode materials.