Multiscale Constitutive Model Development and Finite Element Implementation for Magnetostrictive Materials

2007 ◽  
Author(s):  
William S. Oates
Keyword(s):  
Finite Element ◽  
Constitutive Model ◽  
Axial Magnetic Field ◽  
Mean Field Approximation ◽  
Ferromagnetic Behavior ◽  
Length Scale ◽  
Modeling Framework ◽  
Finite Element Software ◽  
Finite Element Implementation ◽  
Magnetostrictive Materials

A multiscale constitutive model is developed and applied to magnetostrictive materials to predict multi-axial ferromagnetic switching. The modeling framework is an extension of a one-dimensional homogenized energy model that employs a stochastic distribution of localized magnetic moments. Here, the model is extended to multi-axial ferromagnetic switching in a polycrystalline ferromagnetic material. A mean-field approximation is adopted to quantify ferromagnetic switching from multi-axial magnetic field loading at the single crystal length scale. Polycrystalline ferromagnetic behavior is modeled by homogenizing stochastic distributions of underlying microscopic fields associated with material inhomogeneities at the grain length scale. Approximations of the stochastic distributions are made to improve computational efficiency for finite element implementation. The constitutive model is numerically validated and implemented in the commercial finite element software, COMSOL.

EFFECT OF BOUNDARY CONDITIONS ON PROCESS- INDUCED STRESSES IN A PLAIN WEAVE UNIT CELL

2021 ◽  
Author(s):  
K. BUKENYA ◽  
M. N. OLAYA ◽  
E. J. PINEDA ◽  
M. MAIARU
Keyword(s):  
Finite Element ◽  
Boundary Conditions ◽  
Process Modeling ◽  
Complex Geometry ◽  
Polymer Matrix Composites ◽  
Unit Cell ◽  
Modeling Framework ◽  
Element Analysis ◽  
Finite Element Software ◽  
Aerospace Applications

Woven polymer matrix composites (PMCs) are leveraged in aerospace applications for their desirable specific properties, yet they are vulnerable to high residual stresses during manufacturing and their complex geometry makes experimental results difficult to observe. Process modeling is needed to characterize the effects of the curing and predict end stress states. Finite element software can be used to model woven architectures, however accurate representation of processing conditions remains a challenge when it comes to selecting boundary conditions. The effect of BCs on process-induced stress within woven PMCs is studied. The commercial Finite Element Analysis (FEA) software Abaqus is coupled with user-written subroutines in a process modeling framework. A two-dimensionally (2D) woven PMC repeating unit cell (RUC) is modeled with TexGen and Abaqus. Virtual curing is imposed on the bulk matrix. The BC study is conducted with Free, Periodic, Flat, and Flat-Free configurations. Results show that the end stress state is sensitive to the boundary condition assumptions. Flat BC results show great agreement with Periodic BCs. Residual stress results from process modeling are then compared with a linear-elastic thermal cooldown analysis in Abaqus. Cooldown results indicate an overestimation in matrix stresses compared with process modeling.

FINITE ELEMENT IMPLEMENTATION OF A SUPER-ELASTIC CONSTITUTIVE MODEL FOR TRANSFORMATION RATCHETTING OF NiTi ALLOY

2012 ◽  
Vol 09 (01) ◽  
pp. 1240022 ◽  
Author(s):  
Q. H. KAN ◽  
G. Z. KANG ◽  
S. J. GUO
Keyword(s):  
Finite Element ◽  
Constitutive Model ◽  
Niti Alloy ◽  
Cyclic Stress ◽  
Euler Method ◽  
Convergence Criterion ◽  
Integration Algorithm ◽  
Finite Element Implementation ◽  
Backward Euler ◽  
Forward Transformation

In the previous work, a new constitutive model describing the transformation ratchetting of super-elastic NiTi alloy was proposed. The finite element implementation of the proposed model is discussed in this work, because such implementation is necessary to launch a numerical analysis for the cyclic stress–strain responses of NiTi alloy devices including the transformation ratchetting. During the implementation, a new stress integration algorithm is adopted, and a new expression of the consistent tangent modulus is derived for the forward transformation and the reverse transformation. The finite element implementation is elaborated by the user subroutine of UMAT in ABAQUS based on backward Euler method. The accumulated error during cyclic transformation is controlled by a robust convergence criterion. Finally, the validity of such implementation is verified by several numerical examples.

scholarly journals Constitutive model of coupled damage-plasticity and its finite element implementation

2003 ◽  
Vol 12 (4) ◽  
pp. 381-405 ◽  
Author(s):  
Adnan Ibrahimbegović ◽  
Damijan Markovič ◽  
Fabrice Gatuingt
Keyword(s):  
Finite Element ◽  
Constitutive Model ◽  
Finite Element Implementation

Settlement Analysis of Foundation Base on Finite Element Method

2012 ◽  
Vol 204-208 ◽  
pp. 670-673
Author(s):  
Xiao Song ◽  
Hui Zhang ◽  
Guang Sheng Xu
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Constitutive Model ◽  
Contact Element ◽  
Composite Foundation ◽  
Elastic Plastic ◽  
Finite Element Software ◽  
Foundation Base ◽  
Settlement Analysis ◽  
Surrounding Soil

Composite foundation influence parameters were discussed based on Drucker-prager elastic-plastic constitutive model in this paper. Contact element was adopted to simulate the interaction between pile and surrounding soil. Finite element software-ANSYS was applied to study and analyze the distribution and deformation of foundation.

Sign in / Sign up

Export Citation Format

Share Document