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Metallic glasses (MGs) have unusual structural characteristics and resulting unique properties, but effectively modulating their structure is difficult. The recently achieved two-way structural tuning (ordering-disordering) between distinct states in MGs offers an opportunity to overcome this challenge. However, pressures up to tens of GPa were required for the process, which limits sample sizes at the micrometer scale and challenges further comprehensive research. Here, by introducing concurrent shear straining with compressive force using high-pressure torsion, the pressure to trigger the disordering transition is significantly reduced to a few GPa. This enables the acquisition of millimeter-sized samples for comprehensive study, including synchrotron x-ray diffraction and small angle x-ray scatting, nanoindentation, electrical resistivity, and differential scanning calorimetry. It is evidenced that the two-way tuning of MG can be achieved both structurally and thermodynamically, which could help deepen our understanding of the mechanism behind the two-way tuning and promote exploration of distinct MGs. [Display omitted] [ABSTRACT FROM AUTHOR]

Hexagonal silicon (Si-IV) has recently attracted considerable research interest due to its extraordinary optical properties and possibility to convert into a direct semiconductor under strain with great potential for applications. However, the mechanical properties of Si-IV, which are critical for its applications, have not been experimentally studied yet. In this study, combining nanoindentation and in situ high-pressure synchrotron X-ray diffraction, we thoroughly investigated the mechanical properties of Si-IV. The results suggest that the elastic moduli and hardness of Si-IV are close to those of the common diamond cubic silicon. The similar mechanical properties of Si-IV and diamond cubic silicon are beneficial for integrating Si-IV into conventional Si-based devices using similar industrial processing and for its photovoltaic and optoelectronic applications. [Display omitted] [ABSTRACT FROM AUTHOR]