Abstract
For bulk face-centered cubic metals in conventional tests, the effects of sample shape on the yield stress are negligibly small, and the strength dependence on temperature is very weak. Using molecular dynamics simulations, here we demonstrate marked differences in yield stress for Cu pillars with different cross-sectional geometries, or tested at different temperatures, when the sample dimensions are on the nanometer scale. The origin of this change in yield behavior from conventional bulk Cu is explained by analyzing dislocation emission from the surfaces and corners as the mechanism to mediate plasticity. Based on a systematic characterization of the surface structure, atomic-level stresses and strains, a local strain criterion is proposed for yielding in such nanoscale objects.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
