Ulisses Ferreira Kaneko

Multi-technique high resolution X-ray mapping enhanced by the recent advent of 4th generation synchrotron facilities can produce colossal datasets, challenging traditional analysis methods. Such difficulty is clearly materialized when probing the crystal structure of inhomogeneous samples, where the number of diffraction patterns quickly increases with map resolution, making the identification of crystal phases within a vast collection of reflections unfeasibly challenging by direct human inspection. Here we develop an analysis approach based on a physics-informed similarity measure and unsupervised clustering algorithms for identifying independent phases within a diffraction spatial map, which allowed us to identify the material distribution across a high-pressure cerium hydride. By investigating the specific compound, we also contribute to the understanding of synthesis inhomogeneities among the superhydrides, a prominent superconductor class in condensed matter physics whose characterization is highly challenging even for state-of-the-art materials techniques. The analysis framework we present may be readily extended to any correlated set of curves whose features are tied to specific entities such as structural phases.

This study investigated the effects of plasma electrolytic oxidation (PEO) treatment in a Ca- and P-rich electrolyte on the surface of the Ti-6Al-4V alloy with distinct α/β phase proportions previously induced by heat treatments. The results revealed that the α/β phase proportions were successfully altered by the heat treatment temperatures, forming α phase plates surrounded by β phase precipitates. PEO-treated samples exhibited a thick and microsized porous TiO₂ coating in the anatase and rutile crystalline forms. The oxide layer was depleted by Al and V atoms, while Ca and P were gradually enriched along the coatings. Chemical analysis also indicated the absorption of water and organic molecules into the outer layer. PEO-treated samples had microscale roughness and thickness, hydrophilic behavior, and surface energy mainly formed by the dispersive component. The bulk’s elastic modulus decreased with β phase precipitation, while the alloying elements directly influenced the Vickers microhardness. The corrosion tests indicated a stable and protective layer in the PEO-treated samples, showing better corrosion resistance than untreated ones. Overall, the findings indicated that the α and β phase proportion significantly impacts the mechanical properties, while the PEO treatment acts in the corrosion protection and surface aspects, suggesting that combining both approaches could be a powerful tool in biomedical applications.

Glass and glass ceramics are very functional materials, albeit their structural complexity. Their relevance ranges from fundamental science problems in the fields of physics, chemistry, and geoscience, to applications in health areas, engineering, or technological matters that require high performance. Enhancing our understanding of these materials' performance and refining sample preparation methods remains paramount in this field. Synchrotron facilities offer a suite of powerful techniques for the detailed characterization of glasses and glass ceramics. These methods provide valuable insights into their atomic and molecular structure, phase transformations, mechanical behavior, and thermal properties, ultimately contributing to the development of improved materials for a wide range of applications. In‐depth investigations conducted under extreme conditions of pressure and temperature have yielded pivotal insights into densification mechanisms, phase transitions, crystallization kinetics, and their consequential macroscopic properties. The emergence of fourth‐generation synchrotrons brings in a wave of novel experimental possibilities that may exert a profound influence on this field in the coming decade. In this study, we unveil a selection of the remarkable capabilities now accessible to researchers at the Brazilian Synchrotron Light Source—Sirius, within the realm of extreme methods of analysis (EMA) beamline for investigating vitreous systems under extreme conditions.