Temperature and driving rate effects on the yielding transition of amorphous solids
ORAL
Abstract
Abstract: (1154/1300)
The yielding transition in amorphous solids is well studied in the athermal and quasistatic (AQS) limit, where its jerky, avalanching flow is an exemplary realization of self-organized criticality. Crucially, the critical exponents of these avalanches present in quasistatic driving have been connected to the Herschel-Bulkley (HB) exponent that governs the macroscopic response of the material to high driving rates. Here, by equipping a mesoscale elastoplastic model (EPM) for amorphous plasticity with a temperature dependent yielding of weak sites, we investigate how the yielding transition is affected by temperature. We find that avalanche sizes can be truncated by either temperature or finite-size effects and derive a dynamic phase diagram capturing the onset of continuous flow as a function of temperature, driving rate, and system size [1]. We find that in the continuously flowing phase, the HB exponent transitions to a lower value when the temperature is high [1]. We present scaling arguments that connect the smaller temperature truncated avalanches to this high-temperature HB exponent and compare this to alterations in HB scaling found in a related mean-field model.
[1] D. Korchinski and J. Rottler, Dynamic Phase Diagram of Plastically Deformed Amorphous Solids at Finite Temperature, Phys. Rev. E 106, 034103 (2022).
The yielding transition in amorphous solids is well studied in the athermal and quasistatic (AQS) limit, where its jerky, avalanching flow is an exemplary realization of self-organized criticality. Crucially, the critical exponents of these avalanches present in quasistatic driving have been connected to the Herschel-Bulkley (HB) exponent that governs the macroscopic response of the material to high driving rates. Here, by equipping a mesoscale elastoplastic model (EPM) for amorphous plasticity with a temperature dependent yielding of weak sites, we investigate how the yielding transition is affected by temperature. We find that avalanche sizes can be truncated by either temperature or finite-size effects and derive a dynamic phase diagram capturing the onset of continuous flow as a function of temperature, driving rate, and system size [1]. We find that in the continuously flowing phase, the HB exponent transitions to a lower value when the temperature is high [1]. We present scaling arguments that connect the smaller temperature truncated avalanches to this high-temperature HB exponent and compare this to alterations in HB scaling found in a related mean-field model.
[1] D. Korchinski and J. Rottler, Dynamic Phase Diagram of Plastically Deformed Amorphous Solids at Finite Temperature, Phys. Rev. E 106, 034103 (2022).
*This research was undertaken thanks, in part, to funding from the Max Planck-UBC-UTokyo Center for Quantum Materials and the Canada First Research Excellence Fund, Quantum Materials and Future Technologies Program. Financial supported was also provided by the NSERC:PGSD.
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Publication: D. Korchinski and J. Rottler, Dynamic Phase Diagram of Plastically Deformed Amorphous Solids at Finite Temperature, Phys. Rev. E 106, 034103 (2022).
Presenters
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Daniel J Korchinski
- University of British Columbia