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Abstract In this study, a combinatorial and high-throughput approach was leveraged to investigate nanotwin behavior in the ternary CuNiAl alloy system. Combinatorial co-sputtering was used to synthesize 169 unique CuNiAl alloy compositions, which were characterized in both the as-sputtered and annealed conditions to elucidate relationships between composition, nanotwin formation, and phase evolution. Compositional effects on phase formation were investigated using high-throughput X-ray diffraction, while scanning transmission electron microscopy was used to identify nanotwin compositional boundaries and isolate the roles of varied composition and nanotwin formation on microstructural evolution. It was determined that Al content was the primary variable influencing thermal evolution in the nanotwinned CuNiAl alloys, as it altered the thermodynamic driving forces by changing composition and reducing the as-sputtered twin boundary spacing. Overall, this work demonstrates a novel approach to globally study unexplored nanotwin synthesis domains beyond binary alloys. Graphical Abstract 

Abstract The role of interfaces and the controlling synthesis parameters of graded dealloyed nanoporous metallic materials are investigated, focusing on the dealloying front progression in complex precursor materials with multiple alloy compositions. Specifically, the effects of relative density and chemical potential on the dealloying front in sputtered bilayer copper alloy films are explored with two case studies: Cu–Al/Cu–Al and Cu–Al/Cu–Zn. Cross-sectional scanning electron (SEM) micrographs and energy-dispersive X-ray spectroscopy mapping trace the dealloying front across three time intervals, while top-surface and cross-sectional SEM probes the final dealloyed foam morphology. Final ligament sizes were found to be independent of the synthesis parameters (21–28 nm), due to a combination of fast reaction times and phosphate-inhibited surface diffusion of Cu atoms. The chemical potential gradient yielded faster reaction times, whereas slower reaction times and a higher at.% of Cu in the top layer of precursor material produced a more uniform morphology. Graphical abstract 

Abstract The effect of target geometry on coating microstructure and morphology is correlated to changes in deposition conditions, plasma characteristics, and film growth during planar and hollow cathode sputtering. The sputtering plasma properties for the two target geometries were characterized via Langmuir probe analysis as a function of power density and Ar pressure to determine the evolution of ion density for each configuration. Films were then synthesized at the low (0.4 W cm⁻²) and high (1.2 W cm⁻²) power densities and characterized using x-ray diffraction, scanning electron microscopy, and electron backscatter diffraction to link changes in texturing, morphology, and microstructure with variations in ion density and sputtering deposition conditions caused by target geometry. It was observed that varying target geometry led to an over threefold increase in deposition rate, homologous temperature, and ion density, which altered the morphology and texture of the film without significant changes to the grain size.