Influence of Crystallographic Orientation on Energy Dissipation During Sliding

The aim of this study is to evaluate a methodology for modeling the influence of crystallographic grain orientation in sliding contacts. The simulations of translating interfering cylindrical asperities, using finite element analysis, were conducted using two different plasticity models for copper: a conventional isotropic, homogeneous J2 plasticity model and a continuum crystal plasticity model. Using crystal plasticity, the dependence of crystallographic orientation on plastic deformation and energy dissipation can be determined. The relative trends predicted using crystal plasticity are consistent with experiments that show friction depends on crystallographic orientation when plastic deformation is one of the primary energy dissipation mechanisms.

Download Full-text

Influence of Crystallographic Orientation on Energy Dissipation During Sliding

ASME/STLE 2007 International Joint Tribology Conference, Parts A and B ◽

10.1115/ijtc2007-44259 ◽

2007 ◽

Author(s):

Jeremy J. Dawkins ◽

Richard W. Neu

Keyword(s):

Plastic Deformation ◽

Energy Dissipation ◽

Crystal Plasticity ◽

Crystallographic Orientation ◽

Crystal Orientation ◽

Primary Energy ◽

Homogeneous Material ◽

Plasticity Model ◽

Deformation Response ◽

Crystal Plasticity Model

This work presents the results of a finite element study of the sliding contact of interfering cylindrical asperities. One asperity is modeled as elastic with steel properties, while the other asperity is modeled as elastic-plastic copper. The simulations were run using two different plasticity models for copper, conventional J2 plasticity describing an initially homogeneous material and a continuum crystal plasticity model that can capture the influence of crystallographic orientation on the deformation response. The use of the crystal plasticity model and frictionless contact enables us to study the dependence of plastic deformation and energy dissipation as a function of crystal orientation and vertical interference. The relative trends predicted using crystal plasticity are consistent with classical experiments showing the dependence of friction with crystal orientation when plastic deformation is the primary energy dissipation mechanism.

Download Full-text

Finite Element Analysis for Rate-Independent Crystal Plasticity Model

Transactions of the Korean Society of Mechanical Engineers A ◽

10.3795/ksme-a.2009.33.5.447 ◽

2009 ◽

Vol 33 (5) ◽

pp. 447-454 ◽

Cited By ~ 1

Author(s):

Sang-Yul Ha ◽

Ki-Tae Kim

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Crystal Plasticity ◽

Plasticity Model ◽

Element Analysis ◽

Crystal Plasticity Model

Download Full-text

Crystal plasticity model of residual stress in additive manufacturing using the element elimination and reactivation method

Computational Mechanics ◽

10.1007/s00466-021-02116-z ◽

2021 ◽

Author(s):

Nicolò Grilli ◽

Daijun Hu ◽

Dewen Yushu ◽

Fan Chen ◽

Wentao Yan

Keyword(s):

Residual Stress ◽

Plastic Deformation ◽

Additive Manufacturing ◽

Residual Stresses ◽

Crystal Plasticity ◽

Grain Orientation ◽

Large Temperature ◽

Plasticity Model ◽

Crystal Plasticity Model ◽

Element Elimination

AbstractSelective laser melting is receiving increasing interest as an additive manufacturing technique. Residual stresses induced by the large temperature gradients and inhomogeneous cooling process can favour the generation of cracks. In this work, a crystal plasticity finite element model is developed to simulate the formation of residual stresses and to understand the correlation between plastic deformation, grain orientation and residual stresses in the additive manufacturing process. The temperature profile and grain structure from thermal-fluid flow and grain growth simulations are implemented into the crystal plasticity model. An element elimination and reactivation method is proposed to model the melting and solidification and to reinitialize state variables, such as the plastic deformation, in the reactivated elements. The accuracy of this method is judged against previous method based on the stiffness degradation of liquid regions by comparing the plastic deformation as a function of time induced by thermal stresses. The method is used to investigate residual stresses parallel and perpendicular to the laser scan direction, and the correlation with the maximum Schmid factor of the grains along those directions. The magnitude of the residual stress can be predicted as a function of the depth, grain orientation and position with respect to the molten pool. The simulation results are directly comparable to X-ray diffraction experiments and stress–strain curves.

Download Full-text

Analysis of the Necking Behaviors with the Crystal Plasticity Model Using 3-Dimensional Shaped Grains

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.684.357 ◽

2013 ◽

Vol 684 ◽

pp. 357-361 ◽

Cited By ~ 2

Author(s):

Jong Bong Kim ◽

Jeong Whan Yoon

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Crystal Plasticity ◽

Void Nucleation ◽

Damage Model ◽

Initial Imperfection ◽

Plasticity Model ◽

Element Analysis ◽

3 Dimensional ◽

Crystal Plasticity Model

Without initial imperfection and damage evolution model, it is difficult to analyze the necking behavior by finite element analysis with continuum theory. Moreover, the results are greatly dependent on the size of the initial imperfection. In order to predict necking phenomenon without geometric imperfection, in this study, a crystal plasticity model was introduced in the 3-dimensional finite element analysis of tensile test. Grains were modeled by an octahedron and different orientations were allocated to each grain. Damage model was also used to predict the sudden drop of load carrying capacity after necking and to reflect the void nucleation and growth on the severely deformed region. Well-known Cockcroft-Latham damage model was used. Void nucleation, growth and coalescence behavior during necking were predicted reasonably.

Download Full-text