Microstructural evolution and hardening phenomenon caused by aging of AlSi10Mg alloy by laser powder bed fusion.

Microstructures and age-hardening phenomena of directly aged (artificial aged) AlSi10Mg alloys fabricated by laser powder bed fusion (LPBF) were characterized using scanning transmission electron microscopy, atom probe tomography, and Vickers hardness testing. The microstructure derived from overlapping melt pools has a full cellular structure consisting of eutectic Si walls surrounding α-Al cells. In the initial stage of aging, solute clusters with density on the order of 10/m were formed in α-Al cells.

Synthesis of a Mesoporous SnO Catalyst Support and the Effect of Its Pore Size on the Performance of Polymer Electrolyte Fuel Cells.

The aim of this study was to clarify the effectiveness and challenges of applying mesoporous tin oxide (SnO)-based supports for Pt catalysts in the cathodes of polymer electrolyte fuel cells (PEFCs) to simultaneously achieve high performance and high durability. Recently, the focus of PEFC application in automobiles has shifted to heavy-duty vehicles (HDVs), which require high durability, high energy-conversion efficiency, and high power density. It has been reported that employing mesoporous carbon supports improves the initial performance by mitigating catalyst poisoning caused by sulfonic acid groups of the ionomer as well as by reducing the oxygen transport resistance through the Pt/ionomer interface.

Model-based deconvolution for particle analysis applied to a through-focus series of HAADF-STEM images.

This paper presents an approach for determining the sizes and three-dimensional (3D) positions of nanoparticles from a through-focus series of high-angle annular dark-field scanning transmission electron microscopy images. By assuming spherical particles with uniform density, the sizes and 3D positions can be derived via Wiener deconvolution using a series of kernels prepared by the convolution of the 3D point spread function of the electron beam and the 3D density distribution of spheres with different radii. This process is referred to as a model-based deconvolution.

A practical method for determining film thickness using X-ray absorption spectroscopy in total electron yield mode.

Thin films formed on surfaces have a large impact on the properties of materials and devices. In this study, a method is proposed using X-ray absorption spectroscopy to derive the film thickness of a thin film formed on a substrate using the spectral separation and logarithmic equation, which is a modified version of the formula used in electron spectroscopy. In the equation, the decay length in X-ray absorption spectroscopy is longer than in electron spectroscopy due to a cascade of inelastic scattering of electrons generated in a solid.