8 ADVANCED MATERIALS & PROCESSES | JULY/AUGUST 2024 the optimal composition, processing conditions, and microstructure of the magnet for that application, significantly reducing development time. www.nims.go.jp. ATOMIC DISORDER IMPROVES PROPERTIES Researchers from Washington University in St. Louis, Mo., and the University of Southern California, Los Angeles, discovered a new pathway to obtain novel optical and electronic properties from structural disorder. The team found that tiny displacements of just a few picometers in the atomic structure of a crystal could have minimal impacts on optical properties in one direction yet produce huge functional enhancements when viewed from another angle. In their studies, the refractive index of the material changed dramatically with atomic disorder. TESTING | CHARACTERIZATION MODELS LEAD TO BETTER MAGNETS Scientists at the National Institute for Materials Science, Japan, simulated the magnetization reversal of Nd-Fe-B magnets using large-scale finite element models based on tomographic data obtained by electron microscopy. Such simulations have shed light on microstructural features that hinder coercivity, and the new tomography-based models are expected to lead to development of sustainable permanent magnets with improved performance. A new approach to reconstruct the microstructure of ultrafine-grained Nd-Fe-B magnets in large-scale models was proposed in this study. Specifically, the tomographic data from a series of 2D images obtained by scanning electron microscopy in combination with consistent focused ion beam polishing can be converted into a high-quality 3D finite element model. A bonus is that this tomography- based approach is universal and can be applied to other polycrystalline materials addressing a wide range of materials science problems. The micromagnetic simulations on the tomography-based models reproduced the coercivity of ultrafine- grained Nd-Fe-B magnets. The proposed digital twins of the Nd-Fe-B magnets are precise enough to reproduce both the microstructure and magnetic properties, useful for designing high- performance permanent magnets on demand. For example, when researchers input the magnetic properties required for a specific application, a data-driven research pipeline with integrated digital twins would be able to propose Triangular holes make this material more likely to crack from left to right. Courtesy of N.R. Brodnik et al./Phys. Rev. Lett. LIFT, the Department of Defense (DOD) national advanced materials manufacturing innovation institute, launched a project to explore the potential for a new hypersonic and extreme environment test facility at or near Selfridge Air National Guard Base in Michigan. Operating at speeds of Mach 5 or higher, hypersonics and counter-hypersonic vehicles are among the DOD’s top priorities. lift.technology. NSL Analytical Services relocated one of its two Cleveland-area testing laboratories to a new 20,000-sq-ft facility in March. The move doubles the size of its prior metallurgical lab operation and adds hightemperature stress rupture testing for aerospace and additive manufacturing to its offerings. nslanalytical.com. BRIEFS A vector map showing picometer-scale displacements of titanium atoms overlaid onto a scanning transmission electron micrograph that shows the position of different atomic columns. Courtesy of Rohan Mishra and Jayakanth Ravichandran. The processing of FIB-SEM images includes: (a) 2D segmentation; (b) generation of closepacked 3D convex grains; (c) and isolation from each other by the intergranular phase, while triple junctions are made invisible except for zoomed region showing the mesh around one of them. Courtesy of npj Computational Materials (2024). DOI: 10.1038/s41524-024-01218-5. (a) (b) (c)
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