Using scanning and transmission electron microscopy, we studied silicon particles formed during the solidification of Al-7%Si alloy when different modifying mixtures were introduced into the melt: (1) a mixture of ultrafine powders Na3AlF6 + K2ZrF6 + TiO2 + ZrO2; (2) K2ZrF6; and (3) the flux Arsal. By differential scanning calorimetry, it was established that modifying mixtures significantly in...

Resonant x-ray reflectivity of the surface of the liquid phase of the Bi(43)Sn(57) eutectic alloy reveals atomic-scale demixing extending over three near-surface atomic layers. Because of the absence of an underlying atomic lattice which typically defines adsorption in crystalline alloys, studies of adsorption in liquid alloys provide unique insight on interatomic interactions at the surface. T...

Oxidation resistance of the ferritic Fe-Cr-W-Zr alloy with dispersed Fe2Zr phase were investigated in stagnant air and static oxygen-saturated liquid Pb-Bi eutectic separately considering service environment advanced generation IV nuclear reactors. A duplex structure including an outer Fe2O3 layer inner (Fe,Cr,Zr)2O3 is developed after oxidation air, while a three-layered consisting magnetite l...

The amount of the primary phase crystallized in a eutectic alloy at set cooling rate is determined by composition. Only small can be near-eutectic composition alloy. Here we show an interesting phenomenon which microstructure changed application mechanical vibration to Al–Si during from molten metal semi-solid state. α-Al obtained with more than equilibrium solidification. non-equilibrium phase...

Oleg G. Shpyrko,1,2,* Reinhard Streitel,1 Venkatachalapathy S. K. Balagurusamy,1 Alexei Yu. Grigoriev,1 Moshe Deutsch,3 Benjamin M. Ocko,4 Mati Meron,5 Binhua Lin,5 and Peter S. Pershan1 1Department of Physics and School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA 2Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 604...

We report the unusual glass-forming ability (GFA) of a family of Cu-based alloys, Cu46Zr47-xAl7Yx (0<x< or =10, in at. %), and investigate the origin of this unique property. By an injection mold casting method, these alloys can be readily solidified into amorphous structures with the smallest dimension ranging from 4 mm up to 1 cm without detectable crystallinity. Such superior GFA is found pr...

In this study, we demonstrated a new class of frequency-switchable metamaterial absorber in the X-band. Eutectic gallium-indium (EGaIn), a liquid metal alloy, was injected in a microfluidic channel engraved on polymethyl methacrylate (PMMA) to achieve frequency switching. Numerical simulation and experimental results are presented for two cases: when the microfluidic channels are empty, and whe...

In this work the effect of cooling rate on dual-phase (L12/B2) AlCoCrFeNi2.1 Eutectic High-Entropy Alloy was investigated. powders were made using a drop-tube facility, achieving sizes ranging from 850 µm ? d < 1000–38 53 with corresponding estimated rates 114 Ks?1 to 1.75×106 K s?1 respectively. Average interlamellar spacing decreases 2.10 in as-cast alloy 348 nm 38 size fraction. Although dec...

X-ray measurements reveal a crystalline monolayer at the surface of the eutectic liquid Au82Si18, at temperatures above the alloy's melting point. Surface-induced atomic layering, the hallmark of liquid metals, is also found below the crystalline monolayer. The layering depth, however, is threefold greater than that of all liquid metals studied to date. The crystallinity of the surface monolaye...

We have formed compositionally abrupt interfaces in silicon-germanium (Si-Ge) and Si-SiGe heterostructure nanowires by using solid aluminum-gold alloy catalyst particles rather than the conventional liquid semiconductor-metal eutectic droplets. We demonstrated single interfaces that are defect-free and close to atomically abrupt, as well as quantum dots (i.e., Ge layers tens of atomic planes th...