6533b7ddfe1ef96bd1275345

RESEARCH PRODUCT

Plastic yielding of glass in high-pressure torsion apparatus

subject

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International audience; Hardness measurements performed at room temperature have demonstrated that glass can flow under elevated pressure, whereas the effect of high pressure on glass rheology remains poorly quantified. Here, we applied a high-pressure torsion (HPT) apparatus to deform SCHOTT SF6 â glass and attempted to quantify the effect of pressure and temperature on the shear deformation of glass subjected to pressures from 0.3 GPa to 7 GPa and temperatures from 25 ℃ to 496 ℃. Results show that the plastic yield deformation was occurring during the HPT experiments on the SF6 glass at elevated temperature from 350 ℃ to 496 ℃. The yield stress of SF6 glass decreases with increasing temperature and decreasing pressure. An extended Arrhenius model with one set of parameters, namely infinite yield stress Y0=0.17±0.1 GPa, activation energy Ea=4.8±0.5 kJ/mol and activation volume Va=1.4±0.2 cm 3 /mol, can explain the experimental results well.