On tension-compression asymmetry in ultrafine-grained and nanocrystalline metals

Date

2010-12-01

Author

Gürses, Ercan

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We present present a physically motivated computational study explaining the tension/compression (T/C) asymmetry phenomenon in nanocrystalline (nc) and ultrafine-grained (ufg) face centered cubic (fcc) metals utilizing a variational constitutive model where the nc-metal is modeled as a two-phase material consisting of a grain interior phase and a grain boundary affected zone (GBAZ). We show that the existence of voids and their growth in GBAZ renders the material pressure sensitivity due to porous plasticity and that the utilized model provides a physically sound mechanism to capture the experimentally observed T/C asymmetry in nc- and ufg-metals.

Subject Keywords

General Physics and Astronomy, General Materials Science, General Computer Science, Mechanics of Materials, General Chemistry, Computational Mathematics

URI

https://hdl.handle.net/11511/42707

Journal

COMPUTATIONAL MATERIALS SCIENCE

DOI

https://doi.org/10.1016/j.commatsci.2010.09.028

Collections

Department of Aerospace Engineering, Article

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Citation Formats

E. Gürses, “On tension-compression asymmetry in ultrafine-grained and nanocrystalline metals,” COMPUTATIONAL MATERIALS SCIENCE, pp. 639–644, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42707.