Reversible plasticity and multi-periodicity in cyclically sheared amorphous solids

by Mr. Asaf Szulc

at Condensed Matter Seminar

Mon, 30 May 2022, 11:30
Sacta-Rashi Building for Physics (54), room 207


Understanding the response of amorphous materials to time-varying mechanical loads has important implications in different fields, such as mechanical and chemical engineering, materials science, geophysics, and condensed matter physics. When oscillatory shear of small to moderate amplitudes is applied to an amorphous solid, it reaches states where the response to the cyclic forcing is periodic. Furthermore, in many cases, the periodicity is greater than the periodicity of the forcing. This work studied how interactions between elementary plastic events give rise to such multi-periodic responses. We used a graph-theoretical approach that allowed us to identify the individual, reversible, plastic events active during the cycle and a simple model of hysteresis that together allows us to unravel the mechanisms behind multi-periodicity. We show that whereas most reversible plastic events are uni-periodic, some plastic events exhibit periodic stability oscillations around the drive amplitude, which causes the entire system to respond in a multi-periodic manner. We further show that these oscillations stem from cooperative dynamics arising from interactions between plastic events.

Created on 23-05-2022 by Meidan, Dganit (dganit)
Updaded on 23-05-2022 by Meidan, Dganit (dganit)