Why nanoprojectiles work differently than macroimpactors: The role of plastic flow

Atomistic simulation data on crater formation due to the hypervelocity impact of nanoprojectiles of up to 55 nm diameter and with targets containing up to 10^10 atoms are compared to available experimental data on micron-, mm-, and cm-sized projectiles. We show that previous scaling laws do not hold...

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Bibliographic Details
Authors: Anders, Christian, Bringa, Eduardo Marcial, Ziegenhain, Gerolf, Graham, Giles A., Hansen, J. Freddy, Park, Nigel, Teslich, Nick E., Urbassek, Herbert M.
Format: article
Status:Published version
Publication Date:2012
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/199500
Online Access:http://hdl.handle.net/11336/199500
Access Level:Open access
Keyword:craters
molecular dynamics
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Description
Summary:Atomistic simulation data on crater formation due to the hypervelocity impact of nanoprojectiles of up to 55 nm diameter and with targets containing up to 10^10 atoms are compared to available experimental data on micron-, mm-, and cm-sized projectiles. We show that previous scaling laws do not hold in the nanoregime and outline the reasons: within our simulations we observe that the cratering mechanism changes, going from the smallest to the largest simulated scales, from an evaporative regime to a regime where melt and plastic flow dominate, as is expected in larger microscale experiments. The importance of the strain-rate dependence of strength and of dislocation production and motion are discussed.