Temperature–dependent dynamic plasticity of micro-scale fused silica

The ability to predict the micro-scale strength and plasticity of fused-silica micro-components is crucial as their miniaturization applications in harsh environments advance. This study focusses on micro-mechanical behavior fused silica micropillars at high temperatures variable strain rates. 160 with a diameter 1.6 µm have been tested between ?120 °C 600 rates 10-3 s?1 1 s?1, which are date unexplored conditions. Between 300 °C, yield strengths (6–8 GPa) rate sensitivities (?0.03) vary only marginally. However, significant decrease by more than 50 % (2.5–4.5 an increase sensitivity factor 3 (0.09) observed. Post-compression synchrotron-based ptychographic X-ray computed tomography (PXCT) plastically deformed revealed transition deformation mechanisms: Shear-localization shear-promoted densification 25 °C; homogeneous shear-flow limited radial cracking unconstrained due weak confinement °C. FEM results support these observations while separating geometric from material-intrinsic effects. These suggest that classification glass deforms predominantly through should be challenged – least under compression, predominant mode loading applications.