Deformation of Plastically Compressible Hardening-Softening-Hardening Solids

Event details
Date | 14.05.2012 |
Hour | 15:00 › 16:00 |
Speaker | Prof. Alan Needleman, University of North Texas, USA |
Location | |
Category | Conferences - Seminars |
Calculations have shown that a phenomenological elastic-viscoplastic constitutive relation that allows for plastic compressibility can give rise to a progressive buckling-type mode of deformation as seen in experiments on vertically aligned carbon nanotube (VACNT) pillars although a more common response with such a constitutive relation is a propagating instability. A phenomenological constitutive relation that can give rise to this deformation mode is discussed. This constitutive relation is used in 2D and 3D finite deformation, finite element analyses to model the response of compressible hardening-softening-hardening solids under various imposed loadings, including uniaxial compression, uniaxial tension and indentation. The effect of material parameter variations on the mechanical response and the type of instabilities that emerge is considered. Both numerical issues and the issue of extracting material properties from measurements of overall loads and deformations are discussed. The responses of hardening-softening-hardening solids are compared with the corresponding responses of non-softening solids as well as with the phenomenology seen in experiments. This is joint work with Shelby Hutchens, Nisha Mohan and Professor Julia Greer of Caltech.
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Practical information
- General public
- Free
Organizer
- IGM