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Crack‐free monocrystalline β‐normalSiC films having very smooth final surfaces may be reproducibly grown at 1600 K and 760 torr on (100) Si substrates using SiH4 and C2H4 and H2 if the Si is initially reacted with the C2H4 alone. This initial step produces a buffer layer which reduces the mismatches in expansion coefficients and lattice parameters and thus allows the subsequent growth of the β‐normalSiC film to a thickness exceeding 5 μm. It is necessary to heat the Si wafers from room temperature to the reaction temperature in a C2H4 and H2 environment rather than preheating the substrates to the reaction temperature. An off‐axis orientation of the Si in excess of approximately 3° results in a very rough final growth surface on the β‐normalSiC film.

Single-phase solid-solution refractory high-entropy alloys (HEAs) show remarkable mechanical properties, such as their high yield strength and substantial softening resistance at elevated temperatures. Hence, the in-depth study of the deformation behavior for body-centered cubic (BCC) refractory HEAs is a critical issue to explore the uncovered/unique deformation mechanisms. We have investigated the elastic and plastic deformation behaviors of a single BCC NbTaTiV refractory HEA at elevated temperatures using integrated experimental efforts and theoretical calculations. The in situ neutron diffraction results reveal a temperature-dependent elastic anisotropic deformation behavior. The single-crystal elastic moduli and macroscopic Young’s, shear, and bulk moduli were determined from the in situ neutron diffraction, showing great agreement with first-principles calculations, machine learning, and resonant ultrasound spectroscopy results. Furthermore, the edge dislocation–dominant plastic deformation behaviors, which are different from conventional BCC alloys, were quantitatively described by the Williamson-Hall plot profile modeling and high-angle annular dark-field scanning transmission electron microscopy.

We report that a series of lanthanide-based bulk metallic glasses show a pressure-induced polyamorphic phase transition observed by in situ angle-dispersive x-ray diffraction under high pressures. The transition started from a low-density state at lower pressures, and went through continuous densification ending with a high-density state at higher pressures. We demonstrate that, under high pressure, this new type of polyamorphism in densely packed metallic glasses is inherited from its lanthanide-solvent constituent and related to the electronic structure of 4f electrons. The found electronic structure inheritance could provide the guidance for designing new metallic glasses with unique functional physical properties.

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