A molecular-dynamics study of ductile and brittle fracture in model noncrystalline solids
نویسنده
چکیده
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.
منابع مشابه
Ju l 1 99 8 A molecular - dynamics study of ductile and brittle fracture in model noncrystalline solids
A molecular-dynamics study of ductile and brittle fracture in model noncrystalline solids Abstract Molecular-dynamics simulations of fracture in model amorphous solids are shown to exhibit brittle or ductile behavior depending on small changes in interatomic potential. Yet, simulations of these two model solids under pure shear reveal no significant difference in their ultimate yield stress. To...
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