A constitutive model of nanocrystalline metals based on competing grain boundary and grain interior deformation mechanisms

Date

2011-12-01

Author

Gürses, Ercan

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In this work, a viscoplastic constitutive model for nanocrystalline metals is presented. The model is based on competing grain boundary and grain interior deformation mechanisms. In particular, inelastic deformations caused by grain boundary diffusion, grain boundary sliding and dislocation activities are considered. Effects of pressure on the grain boundary diffusion and sliding mechanisms are taken into account. Furthermore, the influence of grain size distribution on macroscopic response is studied. The model is shown to capture the fundamental mechanical characteristics of nanocrystalline metals. These include grain size dependence of the strength, i.e., both the traditional and the inverse Hall-Fetch effects, the tension-compression asymmetry and the enhanced rate sensitivity.

Subject Keywords

Mechanical Engineering, General Materials Science, Mechanics of Materials, Condensed Matter Physics

URI

https://hdl.handle.net/11511/36287

Journal

MATERIALS LETTERS

DOI

https://doi.org/10.1016/j.matlet.2011.07.039

Collections

Department of Aerospace Engineering, Article

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Citation Formats

E. Gürses, “A constitutive model of nanocrystalline metals based on competing grain boundary and grain interior deformation mechanisms,” MATERIALS LETTERS, pp. 3391–3395, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36287.