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The electronic structure inheritance of lanthanide-solvent atoms in lanthanide-based metallic glasses has been proposed. Is a polyamorphism possible in lanthanide-solute metallic glasses? So far, polyamorphic phase transitions in metallic glass containing lanthanide have been observed only in lanthanide-solvent metallic glasses. Here, a pressure-induced transition between two distinct amorphous states, accompanied by a 7% volume collapse at ambient pressure, was observed in La43.4Pr18.6Al14Cu24 metallic glass, with low lanthanide content, by using in situ X-ray total scattering method. The transformation also indicated by changes in short range and medium range order. Thus, it is proposed that the lanthanide-solute metallic glasses also inherit 4f electronic transition from pure lanthanide element in polyamorphic transition. This discovery offers a supplement to research on lanthanide-based metallic glasses, which further provides a new perspective of the polyamorphic transformation in metallic glasses containing lanthanide element.

In this paper, TiC p /Ni 3 Al composites are synthesized in situ at near theoretical density under high-pressure (1.5-6.5 GPa), high-temperature (1073-1473 K) conditions. The grain size of TiC-reinforced particles is nanometer scale, which influences the Vickers microhardness of the composites. The effect of pressure on the grain size of TiC is discussed.

Using diamond anvil cell (DAC) technique, in situ high-pressure Raman scattering and energy-dispersive X-ray diffraction (EDXRD) experiments were used at room temperature to study 3C-SiC with an average grain size of 30 nm. In contrast to its bulk counterpart, a decrease of the Born's transverse effective charge of these nanocrystals was observed with increasing pressure from measurements of the longitudinal and transverse optical phonon modes (longitudinal optical-transverse optical) splitting. This is therefore indicative of a diminishing ionicity of nanocrystalline 3C-SiC on compression.

Using the diamond anvil cell technique, angle-dispersive X-ray diffraction and Raman spectroscopy were employed to study the high pressure behavior of mercury cyanamide. Its decomposition under pressure starts at 1.9 GPa and is not completed even up to 10 GPa. The decomposition product α-Hg transforms to β-Hg during 7–10 GPa, while the C/N residual is not detectable by X-ray diffraction. The zero pressure bulk modulus of mercury cyanamide is estimated as 38.5 GPa.

In this paper, TiC p /Ni 3 Al composites are synthesized in situ at near theoretical density under high-pressure (1.5-6.5 GPa), high-temperature (1073-1473 K) conditions. The grain size of TiC-reinforced particles is nanometer scale, which influences the Vickers microhardness of the composites. The effect of pressure on the grain size of TiC is discussed.

Using the diamond anvil cell technique, angle-dispersive X-ray diffraction and Raman spectroscopy were employed to study the high pressure behavior of mercury cyanamide. Its decomposition under pressure starts at 1.9 GPa and is not completed even up to 10 GPa. The decomposition product α-Hg transforms to β-Hg during 7–10 GPa, while the C/N residual is not detectable by X-ray diffraction. The zero pressure bulk modulus of mercury cyanamide is estimated as 38.5 GPa.