Elasticity in Amorphous Solids: Nonlinear or Piece-Wise Linear?

Autor: Dubey, Awadhesh K., Procaccia, Itamar, Shor, Carmel A. B. Z., Singh, Murari
Rok vydání: 2015
Předmět:
Zdroj: Phys. Rev. Lett. 116, 085502 (2016)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevLett.116.085502
Popis: Quasi-static strain-controlled measurements of stress vs strain curves in macroscopic amorphous solids result in a nonlinear looking curve that ends up either in mechanical collapse or in a steady-state with fluctuations around a mean stress that remains constant with increasing strain. It is therefore very tempting to fit a nonlinear expansion of the stress in powers of the strain. We argue here that at low temperatures the meaning of such an expansion needs to be reconsidered. We point out the enormous difference between quenched and annealed averages of the stress vs. strain curves, and propose that a useful description of the mechanical response is given by a stress (or strain) dependent shear modulus for which a theoretical evaluation exists. The elastic response is piece-wise linear rather than nonlinear.
Comment: 5 pages, 5 figures
Databáze: arXiv