scholarly journals Constitutive Model of Shape Memory Alloy and its Finite Element Implementation for Medical Applications

2016 ◽  
Author(s):  
Yanping Wang
Keyword(s):  
Finite Element ◽  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory ◽  
Medical Applications ◽  
Finite Element Implementation

A constitutive model for Fe-based shape memory alloy considering martensitic transformation and plastic sliding coupling: Application to a finite element structural analysis

2012 ◽  
Vol 23 (10) ◽  
pp. 1143-1160 ◽  
Author(s):  
Walid Khalil ◽  
Alain Mikolajczak ◽  
Céline Bouby ◽  
Tarak Ben Zineb
Keyword(s):  
Finite Element ◽  
Phase Transformation ◽  
Structural Analysis ◽  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory ◽  
Internal Variables ◽  
Thermomechanical Loading ◽  
Proposed Model ◽  
Numerical Tool

In this article, we propose a finite element numerical tool adapted to a Fe-based shape memory alloy structural analysis, based on a developed constitutive model that describes the effect of phase transformation, plastic sliding, and their interactions on the thermomechanical behavior. This model was derived from an assumed expression of the Gibbs free energy taking into account nonlinear interaction quantities related to inter- and intragranular incompatibilities as well as mechanical and chemical quantities. Two scalar internal variables were considered to describe the phase transformation and plastic sliding effects. The hysteretic and specific behavior patterns of Fe-based shape memory alloy during reverse transformation were studied by assuming a dissipation expression. The proposed model effectively describes the complex thermomechanical loading paths. The numerical tool derived from the implicit resolution of the nonlinear partial derivative constitutive equations was implemented into the Abaqus® finite element code via the User MATerial (UMAT) subroutine. After tests to verify the model for homogeneous and heterogeneous thermomechanical loadings, an example of Fe-based shape memory alloy application was studied, which corresponds to a tightening system made up of fishplates for crane rails. The results we obtained were compared to experimental ones.

Finite element simulation of ferromagnetic shape memory alloys using a revised constitutive model

2017 ◽  
Vol 28 (19) ◽  
pp. 2853-2871 ◽  
Author(s):  
Siavash Jafarzadeh ◽  
Mahmoud Kadkhodaei
Keyword(s):  
Finite Element ◽  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Model Parameters ◽  
Ferromagnetic Shape Memory Alloy ◽  
Ferromagnetic Shape Memory Alloys ◽  
Numerical Predictions ◽  
Ferromagnetic Shape Memory

In this article, a previously developed constitutive model for ferromagnetic shape memory alloys is phenomenologically enhanced using experimental observations. A modified phase diagram along with a method for calibration of the required model parameters is further presented. The model is implemented into a user material subroutine to equip commercial finite element software ABAQUS with the capability of simulating magneto-mechanical behaviors of ferromagnetic shape memory alloys. A combined convergence scheme is employed to solve the implicit equations. The proposed model together with the presented numerical solution is shown to be able to study shape memory effect and pseudoelasticity at different constant magnetic fields. The simulated magnetic loading/unloading cycles at different constant stresses are found to be well-fitted to the experimental findings. As a practical application of the ferromagnetic shape memory alloy coupled magneto-mechanical response, a spring actuator (a bias spring serially connected to one ferromagnetic shape memory alloy element) is investigated, and the numerical predictions are shown to be in a good agreement with available experimental results. As a novel case, geometrically graded NiMnGa elements are also introduced and are simulated with the use of this approach.

scholarly journals Finite Element Analysis for the Self-Loosening Behavior of the Bolted Joint with a Superelastic Shape Memory Alloy

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1592 ◽  
Author(s):  
Xiangjun Jiang ◽  
Jin Huang ◽  
Yongkun Wang ◽  
Baotong Li ◽  
Jingli Du ◽  
...  
Keyword(s):  
Finite Element ◽  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory ◽  
Computational Procedure ◽  
The Self ◽  
External Loading ◽  
Bolted Joint ◽  
Element Analysis ◽  
Dissipation Energy

A macroscopic constitutive model is proposed in this research to reproduce the uniaxial transition ratcheting behaviors of the superelastic shape memory alloy (SMA) undergoing cyclic loading, based on the cosine-type phase transition equation with the initial martensite evolution coefficient that provides the predictive residual martensite accumulation evolution and the nonlinear feature of hysteresis loop. The calculated results are compared with the experimental results to show the validity of the present computational procedure in transition ratcheting. Finite element implementation for the self-loosening behavior of the superelastic SMA bolt is then carried out based on the proposed constitutive model to analyze the curves of stress-strain responses on the bolt bar, clamping force reduction law, dissipation energy change law of the bolted joint for different external loading cases, and preload force of the bolt.

scholarly journals Finite Element Modeling of A phenomenological Constitutive Model for Super-elastic Shape Memory Alloy and its Application for Preload Process Analysis of Bolted Joint

2018 ◽  
Author(s):  
Xiangjun Jiang ◽  
Jin Huang ◽  
Yongkun Wang ◽  
Fengqun Pan ◽  
Baotong Li ◽  
...  
Keyword(s):  
Finite Element ◽  
Shape Memory Alloy ◽  
Constitutive Model ◽  
Shape Memory ◽  
Volume Fraction ◽  
Process Analysis ◽  
Bolted Joint ◽  
Integration Algorithm ◽  
Applied Loading ◽  
Proposed Model

A phenomenological constitutive model is developed to describe the uniaxial transformation ratcheting behaviors of super–elastic shape memory alloy (SMA) by employing a cosine–type phase transformation equation with the initial martensite evolution coefficient that can capture the feature of the predictive residual martensite accumulation evolution and the nonlinear hysteresis loop on a finite element (FE) analysis framework. The effect of the applied loading level on transformation ratcheting are considered in the proposed model. The evolutions of transformation ratcheting and transformation stresses are constructed as the function of the accumulated residual martensite volume fraction. The FE implementation of the proposed model is carried out for the numerical analysis of transformation ratcheting of the SMA bar element. The integration algorithm and the expression of consistent tangent modulus are deduced in a new form for the forward and reverse transformation. The numerical results are compared with those of existing model and the experimental results to show the validity of the proposed model and its FE implementation in transformation ratcheting. Finally, a FE modeling is established for a repeated preload analysis of SMA bolted joint

Sign in / Sign up

Export Citation Format

Share Document