Dynamic Failure in Amorphous Solids via a Cavitation Instability

TL;DR

This paper investigates the dynamic failure of amorphous solids through cavitation instability, incorporating elasticity and visco-plasticity using Shear Transformation Zone theory to reveal fast cavitation modes with plastic deformation.

Contribution

It introduces a combined elastic and visco-plastic model for cavitation failure in amorphous materials using Shear Transformation Zone theory, highlighting new fast cavitation modes.

Findings

Existence of fast cavitation modes in amorphous systems

Plastic deformations accompany cavitation modes

Insights into failure physics of amorphous solids

Abstract

The understanding of dynamic failure in amorphous materials via the propagation of free boundaries like cracks and voids must go beyond elasticity theory, since plasticity intervenes in a crucial and poorly understood manner near the moving free boundary. In this Letter we focus on failure via a cavitation instability in a radially-symmetric stressed material, set up the free boundary dynamics taking both elasticity and visco-plasticity into account, using the recently proposed athermal Shear Transformation Zone theory. We demonstrate the existence (in amorphous systems) of fast cavitation modes accompanied by extensive plastic deformations and discuss the revealed physics.