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A molecular-dynamics study of ductile and brittle fracture in model non-crystalline solids

M. L. Falk
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Abstract

Molecular-dynamics simulations of fracture in metallic glass-like systems are observed to undergo embrittlement due to a small change in interatomic potential. This change in fracture toughness, however, is not accompanied by a corresponding change in flow stress. Theories of brittle fracture proposed by Freund and Hutchinson indicate that strain rate sensitivity is the controling physical parameter in these cases. A recent theory of viscoplasticity in this class of solids by Falk and Langer further suggests that the change in strain rate sensitivity corresponds to a change in the susceptibility of local shear transformation zones to applied shear stresses. A simple model of these zones is develped in order to quantify the dependence of this sensitivity on the interparticle potential.

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M. L. Falk. 1999-02-08. A molecular-dynamics study of ductile and brittle fracture in model non-crystalline solids. https://doi.org/10.1103/physrevb.60.7062

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