One of the challenges of advanced simulation with Abaqus is knowing how to represent the materials in your structure. Defining a simple linear elastic material model is pretty straightforward. Defining a nonlinear elastic material, such as a rubber or elastomer material is a bit more complicated, but we have some well-developed courses to attend to learn more about that subject. Rubber and elastomeric materials can get even more complicated than just their nonlinear elastic behavior, exhibiting significant viscous behavior and something called Mullin's damage. The image above shows test data exhibiting all of these behaviors. It is very common that one needs to decide which behavior is important for your particular application. Trying to develop an "all-encompassing" material model that captures things such as rate dependence, temperature dependence, etc., is often not required to get some good design guidance from simulation.
We are going to create a series of e-learning posts that address common issues in material modeling and calibration. This post will act as both an overview and curriculum. Please check back on this post from time to time as we will be adding material every month or so.
If the material behavior you are trying to replicate is homogeneous within the measured part of the specimen, then calibration can be carried out using equations – if you know them. Two common non-homogeneous deformations are i) necking in a tensile test and ii) compression puck with friction. For non-homogeneous deformations, we often use multi-element Abaqus analyses for calibration. Other times, the deformation might be homogeneous, but you don’t know the stress-strain relation equations (in closed form). In that case we often use Abaqus analysis of a “unit-cube” for calibration. We will have individual posts that describe each of these types of calibration approaches.
A New Material Model Calibration App in the 3DEXPERIENCE Platform
Fun with Flags (Fun with Error Norms)
Using Extensometer test data in material model calibration
Using NN Surrogates for material model calibration
Using NN surrogates for material calibration: example 2
Material Modeling Symposium at the SAoE - June 18, 2018
Continuum Damage Mechanics: References
General Questions about Materials Modeling
Calibration of a homogeneous deformation using closed-form equations in Excel:
(some of these examples also show the use of Abaqus/CAE for calibration)
Neo-Hookean Calibration of an Elastomer
Yeoh Model Calibration of an Elastomer
Understanding Prony series viscoelasticity - Part 1
Understanding Prony series viscoelasticity - Part 2 (relation between storage & loss moduli and Prony series)
Calibration of Prony series from DMA test data
Linear and Nonlinear Viscoelasticity (updated Feb, 2021)
Converting a *HYSTERESIS model to PRF form
DMA Conversion Parameters, New in R2021x FD05
Time-Temperature Superposition (TTS), TRS, WLF
Time-Temperature Superposition using DMA test data
Calibration of a homogeneous deformation using a unit-cube in Abaqus:
Hyperelasticity with Permanent Set; Demo of Calibration in A/CAE
Calibration of a non-homogeneous deformation using Isight + Abaqus:
Isight Calibration of a Bonded Rubber Puck
General Purpose Calibration using Isight optimization:
Isight Corner : How to calibrate materials using Isight?
Integrated Hyper+Prony Calibration solution for the time varying response of elastomers
Modeling and Calibration of Polymers and Plastics:
Playback - eSeminar on “Modeling of Polymers and Plastics with Abaqus”
Modeling of Adhesives
Calibration of a PRF Material Model for Polypropylene
Multiscale Material Modeling (micromechanics):
Multiscale Material Modeling in Abaqus/CAE with NASA's FEAMAC: Introduction
Multiscale Material Modeling in Abaqus/CAE with NASA's FEAMAC: Workshop Example 1
Multiscale Material Modeling in Abaqus/CAE with NASA's FEAMAC: Workshop Example 2
We will use this post to organize test data that can be shared:
Sharing Material Test Data - new material added Nov, 2024
We will use this post to organize test specimen models that can be shared:
Sharing Abaqus test specimen models
We will use this post to share UMATs and VUMATs:
Sharing Abaqus UMATs, VUMATs, and User-Subs
Future posts will cover these other topics:
General testing issues, common measurements issues, raw test data cleanup, extensometers (averaging), DIC methods
calibration tools – Excel, A/CAE, A/CAE plugins, Isight, MCalibration
Using tensile dogbone Abaqus models for calibration of necking
Defining a power law plasticity model for post-necking simulation in metals
Error norms ?
DS Knowledgebase Resources:
Creating custom material calibration plug-ins in Abaqus/CAE
Abaqus/CAE plug-in utility to calibrate Nitinol material behavior
Using cyclic stress-strain curves with kinematic hardening plasticity in Abaqus
Good reference papers for Abaqus material models (link to AUC/SCC paper search):
Yang, et al, 2001 AUC ; (covers hyperelasticity, viscoelasticity and WLF)
Experimental Characterisation and Modelling of Rubber for ABAQUS
Kim, et al, 2009 SCC ; (covers Drucker Prager and DR creep for plastics):
Strowig, et al, 2011 SCC ; (DIC measurements) :
Please comment on the area of material modeling and calibration that you would like to see discussed !
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