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

Date

2010-12-01

Author

Gürses, Ercan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

133
views

0
downloads

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

Suggestions

OpenMETU
Core

Application of non-convex rate dependent gradient plasticity to the modeling and simulation of inelastic microstructure development and inhomogeneous material behavior Klusemann, Benjamin; Yalçınkaya, Tuncay; Geers, M. G. D.; Svendsen, Bob (Elsevier BV, 2013-12-01) In this study, a two-dimensional rate-dependent gradient crystal plasticity model for non-convex energetic hardening is formulated and applied to the simulation of inelastic microstructure formation. In particular, non-convex hardening is modeled via a Landau-Devonshire potential for self-hardening and two interaction-matrix-based forms for latent hardening. The algorithmic formulation and the numerical implementation treats the displacement and the glide-system slips as the primary field variables. The num...
Three dimensional computational analysis of fatigue crack propagation in functionally graded materials Sabuncuoglu, Baris; Dağ, Serkan; YILDIRIM, BORA (Elsevier BV, 2012-02-01) This article proposes a new finite elements based three dimensional method developed to study the phenomenon of fatigue crack propagation in functionally graded materials (FGMs). The particular problem examined in detail is that of an initially-elliptical crack located in a functionally graded medium, subjected to mode I cyclic loading. The crack is modelled by employing three dimensional finite elements; and the stress intensity factors (SIFs) around the crack front are computed by the application of the d...
Analysis and simulation of the backscattering enhancement phenomenon from randomly distributed point scatterers Ağar, Kartal Şahin; Koç, Seyit Sencer; Department of Electrical and Electronics Engineering (2007) This thesis investigates analysis and simulation of the backscattering enhancement phenomenon from randomly distributed point scatterers. These point scatterers are randomly distributed within a cube or a sphere and then the backscattering enhancement phenomenon from both cubical and spherical distributions are examined throughout the thesis. The general characteristic differences between cubical and spherical distribution about the scattering phenomenon are observed. T-matrix method is used for analytic in...
Higher order approximate dynamic models for layered composites Yalcin, Omer Fatih; Mengi, Yalcin; Turhan, Dogan (Elsevier BV, 2007-05-01) Based on a higher order dynamic approximate theory developed in the present study for anisotropic elastic plates, two dynamic models, discrete and continuum models (DM and CM), are proposed for layered composites. Of the two models, CM is more important, which is established in the study of periodic layered composites using smoothing operations. CM has the properties: it contains inherently the interface and Floquet conditions and facilitates the analysis of the. composite, in particular, when the number of...
Exponential stability of periodic solutions of recurrent neural networks with functional dependence on piecewise constant argument Akhmet, Marat; Cengiz, Nur (The Scientific and Technological Research Council of Turkey, 2018-01-01) In this study, we develop a model of recurrent neural networks with functional dependence on piecewise constant argument of generalized type. Using the theoretical results obtained for functional differential equations with piecewise constant argument, we investigate conditions for existence and uniqueness of solutions, bounded solutions, and exponential stability of periodic solutions. We provide conditions based on the parameters of the model.

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.