Year: 2024
Type: article
Abstract: Pressure-induced phase transformations (PTs) in Si, the most important electronic material, have been broadly studied, whereas strain-induced PTs have never been studied in situ. Here, we reveal in situ various important plastic strain-induced PT phenomena. A correlation between the direct and inverse Hall-Petch effect of particle size on yield strength and pressure for strain-induced PT is predicted theoretically and confirmed experimentally for Si-I→Si-II PT. For 100 nm particles, the strain-induced PT Si-I→Si-II initiates at 0.3 GPa under both compression and shear while it starts at 16.2 GPa under hydrostatic conditions. The Si-I→Si-III PT starts at 0.6 GPa but does not occur under hydrostatic pressure. Pressure in small Si-II and Si-III regions of micron and 100 nm particles is ∼5-7 GPa higher than in Si-I. For 100 nm Si, a sequence of Si-I → I + II → I + II + III PT is observed, and the coexistence of four phases, Si-I, II, III, and XI, is found under torsion. Retaining Si-II and single-phase Si-III at ambient pressure and obtaining reverse Si-II→Si-I PT demonstrates the possibilities of manipulating different synthetic paths. The obtained results corroborate the elaborated dislocation pileup-based mechanism and have numerous applications for developing economic defect-induced synthesis of nanostructured materials, surface treatment (polishing, turning, etc.), and friction.
Source: Nature Communications
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,790
Funders: National Science Foundation, U.S. Department of Defense, U.S. Department of Energy, Iowa State University, Office of Science, National Nuclear Security Administration, Division of Materials Research, Division of Civil, Mechanical and Manufacturing Innovation, Army Research Office, Argonne National Laboratory
Awards: G102163711, G107546177, G1313983767, G1664757510, New Rules for Coupled Severe Plastic Deformations, Phase Transformations, and Structural Changes in Metals under High Pressure, G2287611682, G262962599, G2959414255, G3075337988, G3318903820, G3589692066, G419621733, G4402414094, G498139845, G513797252, G5737615044, DEFORMATIONAL, TRANSFORMATIONAL, AND MICROSTRUCTURAL MATERIAL BEHAVIOR OF SELECTED MATERIALS UNDER HIGH PRESSURE, SEVERE PLASTIC DEFORMATIONS, AND HIGH STRAIN RATES, Plasticity, Phase Transformations, and their Interaction under High Pressure in Silicon, G6848031779, G6918803902, G7450529542, G908003055, G969889393, G993149817
OpenAlex ID: W4401605967