Nucleation of plasticity in nanoparticle collisions

While at small collision velocities collisions of nanoparticles (NPs) are elastic, they become plastic at higher velocities. We study the elastic-plastic threshold and the onset of plasticity using molecular dynamics simulation for a Lennard-Jones material. The reasons behind the R-2/3 increase of t...

Full description

Bibliographic Details
Authors: Millán, Emmanuel Nicolás, Tramontina Videla, Diego Ramiro, Urbassek, Herbert M., Bringa, Eduardo Marcial
Format: article
Status:Published version
Publication Date:2016
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/56501
Online Access:http://hdl.handle.net/11336/56501
Access Level:Open access
Keyword:Nanoparticles
Molecular Dynamics
Plasticity
Nucleation
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Description
Summary:While at small collision velocities collisions of nanoparticles (NPs) are elastic, they become plastic at higher velocities. We study the elastic-plastic threshold and the onset of plasticity using molecular dynamics simulation for a Lennard-Jones material. The reasons behind the R-2/3 increase of the threshold velocity for small NP radii R found recently are discussed. At the threshold, NP orientation strongly influences the generation of plasticity, and averaging over many orientations is required to predict the critical velocity for dislocation generation. The onset of plasticity is governed by the generation of isolated stacking faults and nanotwins spanning the entire NP. At higher velocities, the fraction of defects becomes proportional to the total number of atoms in the NP.