University of Illinois Urbana-Champaign

Surface stress and reversing size effect in the initial yielding of ultrathin films

Gioia, Gustavo; Dai, Xiangyu

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https://hdl.handle.net/2142/327

Description

Title
Surface stress and reversing size effect in the initial yielding of ultrathin films
Author(s)
  • Gioia, Gustavo
  • Dai, Xiangyu
Issue Date
2005-08
Abstract
Very recent experiments indicate that in free-standing metallic films of constant grain size the initial yield stress increases as the film becomes thinner, it peaks for a thickness on the order of 100 nm, and then starts to decrease. This reversing size effect poses two challenges: (1) It cannot be explained using currently available models and (2) it appears to contradict the classical experimental results due to J. W. Beams. Here we show that the reversing size effect can be explained and the contradiction dispelled by taking into account how the initial yielding is affected by the surface stress. We also predict that the mode of failure of a film changes from ductile to brittle for a thickness on the order of 100 nm, in accord with experiments.
Publisher
Department of Theoretical and Applied Mechanics (UIUC)
Series/Report Name or Number
TAM Reports 1069, (2005)
ISSN
0073-5264
Type of Resource
text
Language
en
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http://hdl.handle.net/2142/327

Owning Collections

Technical Reports - Theoretical and Applied Mechanics (TAM) PRIMARY
TAM technical reports include manuscripts intended for publication, theses judged to have general interest, notes prepared for short courses, symposia compiled from outstanding undergraduate projects, and reports prepared for research-sponsoring agencies.