May 27, 2025 | by DatapointLabs | views 102
The accurate calibration of materials models is crucial for simulating the behavior of materials across various industries, including automotive, aerospace, and consumer goods. With the increasing complexity of modern materials, particularly polymers, foams, and composite materials, developing reliable and efficient calibration strategies is more important than ever. This paper presents a comprehensive comparative analysis of calibration strategies for material models applied to these materials, focusing on the challenges and best practices for each material class.
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Plastics
Foams
Composites
Presentations
Validation
March 10, 2025 | by Datapoint Newsletters | views 548
Applus+ DatapointLabs marks 30th anniversary; latest research; 2025 events
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Plastics
Foams
Composites
Research Papers
Newsletters
Quality
March 03, 2025 | by DatapointLabs | views 657
The accurate calibration of materials models is crucial for simulating the behavior of materials across various industries, including automotive, aerospace, and consumer goods. With the increasing complexity of modern materials, particularly polymers, foams, and composite materials, developing reliable and efficient calibration strategies is more important than ever. This paper presents a comprehensive comparative analysis of calibration strategies for material models applied to these materials, focusing on the challenges and best practices for each material class.
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Plastics
Foams
Composites
Presentations
Validation
May 22, 2023 | by Datapoint Newsletters | views 2471
DatapointLabs Founders Retire; Company Continues Focus on Materials in Simulation
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Thermal
Mechanical
Foams
Newsletters
Validation
May 15, 2023 | by DatapointLabs | views 2222
Simulations play a crucial role in engineering and material science, and their success heavily relies on the accuracy of input data. Material testing, data conversion, fitting, and formatting are essential steps in the simulation process. This conference will highlight the importance of material testing requirements that extend beyond ISO and ASTM standards to obtain reliable data for input into various common material models, such as Elastic-Plastic, Hyperelastic, and Rate Dependent models. The complexity of foam materials is shown through a case study of successful validation of polyurethane (PU) foam ball drop impact test using LAW 90. PU foams exhibit high deformation with rate dependency in compressive loading, as well as viscoelastic unloading behavior. Proper handling of input test data and critical settings in simulation setup are crucial for accurate results. The case study will showcase our streamlined approach to successful simulation of foam materials, including challenges and limitations of current material models.
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Mechanical
Foams
Hyperelastic
Rate Dependency
Altair RADIOSS
Validation
June 03, 2016 | by DatapointLabs | views 8452
This book is intended to be a companion to the NAFEMS book, "An Introduction to the Use of Material Models in FE". It informs Finite Element Analysis users of the manner and methodologies by which materials are tested in order to calibrate material models currently implemented in various FEA programs. While the authors seek first to satisfy the basic material models outlined in the companion book, they make important extensions to FEA used in currently active areas including explicit simulation.
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Mechanical
Plastics
Rubbers
Foams
Metals
Hyperelastic
Viscoelastic
Plasticity
Rate Dependency
Yielding/Failure Analysis
Aerospace and Defense
Automotive
Biomedical
Building Materials
Consumer Products
Energy and Petroleum
Material Supplier
Furniture
Industrial Goods
CAE Vendor/Supplier
Packaging
Home Appliances
Research Laboratory
High Speed Testing
Nonlinear Material Models
Structural Analysis
LS-DYNA
Abaqus
ANSYS
DIGIMAT
SOLIDWORKS
MSC.DYTRAN
MSC.MARC
MSC.NASTRAN
NX Nastran
PAM-COMFORT
PAM-CRASH
Altair RADIOSS
SIMULIA
Book Review
July 30, 2015 | by Helmut Gese | views 4807
"Today the automotive industry is faced with the demand to build light fuel-efficient vehicles while
optimizing its crashworthiness and stiffness. A wide variety of new metallic and polymeric materials
have been introduced to account for these increased requirements. Numerical analysis can
significantly support this process if the analysis is really predictive. Within the numerical model a
correct characterization of the material behaviour – including elasto-viscoplastic behaviour and failure
- is substantial. The particular behaviour of each material group must be covered by the material
model.
The user material model MF GenYld+CrachFEM allows for a modular combination of
phenomenological models (yield locus, strain hardening, damage evolution, criteria for fracture
initiation) to give an adequate representation of technical materials. This material model can be linked
to LS-DYNA when using the explicit-dynamic time integration scheme.
This paper gives an overview on the material characterization of ultra high strength steels (with focus
on failure prediction), non-reinforced polymers (with focus on anisotropic hardening of polymers), and
structural foams (with focus on compressibility and stress dependent damage evolution) with respect
to crash simulation. It will be shown that a comprehensive material model - including damage and
failure behaviour - enables a predictive simulation without iterative calibration of material parameters.
A testing programme has been done for each material group in order to allow a fitting of the
parameters of the material model first. In a second step different component tests have been carried
out, which were part of a systematic procedure to validate the appropriate predictions of the crash
behaviour with LS-Dyna and user material MF_GenYld+CrachFEM for each material group."
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Mechanical
Plastics
Foams
Metals
Rate Dependency
Yielding/Failure Analysis
Automotive
High Speed Testing
LS-DYNA
Research Papers
July 27, 2015 | by Paul Du Bois | views 4821
"Recently new materials were introduced to enhance different aspects of automotive safety while minimizing the
weight added to the vehicle. Such foams are no longer isotropic but typically show a preferred strong direction due
to their manufacturing process. Different stress/ strain curves are obtained from material testing in different
directions. A new material model was added to the LS-DYNA code in order to allow a correct numerical simulation
of such materials. Ease-of-use was a primary concern in the development of this user-subroutine: we required stress/
strain curves from material testing to be directly usable as input parameters for the numerical model without
conversion. The user-subroutine is implemented as
MAT_TRANSVERSELY_ANISOTROPIC_CRUSHABLE_FOAM, Mat law 142 in LS-DYNA Version 960-1106.
In this paper we summarize the background of the material law and illustrate some applications in the field of
interior head-impact. The obvious advantage of incorporating such detail in the simulation lies in the numerical
assessment of impacts that are slightly offset with respect to the foam’s primary strength direction."
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Mechanical
Foams
Rate Dependency
Automotive
High Speed Testing
LS-DYNA
Research Papers
July 27, 2015 | by Paul Du Bois | views 4574
Lightweight design is one of the major principles in automotive engineering and has made polymer materials to inherent parts of modern cars. In addition to their lightweight thermoplastics, elastomers, fabric and composites also incur important functions in passive safety. In the age of virtual prototyping, assuring these functions requires the accurate modeling of the mechanical behavior of each component. Due to their molecular structure, polymer materials often show viscoelastic characteristics such as creep, relaxation and recovery. However, considering the general state of the art in crash simulation, the viscoelastic characteristics are mainly neglected or replaced by viscoplastic or hyperelastic and strain rate dependent material models. This is either due to the available material models that are often restricted to linear viscoelasticity and thus cannot model the experimental data or due to the time consuming parameter identification. In this study, a nonlinear viscoelastic material model for foams is developed and implemented as a user material subroutine in LS-DYNA. The material response consists of an equilibrium and a non-equilibrium part. The first one is modeled with a hyperelastic formulation based on the work of Chang [8] and formerly implemented as *MAT_FU_CHANG_FOAM in LS-DYNA (*MAT_083). The second one includes the nonlinear viscoelastic behavior following the multiple integral theory by Green and Rivlin [9]. The polyurethane foam Confor CF-45 used as part of the legform impactor in pedestrian safety was chosen for its highly nonlinear viscoelastic properties to test the presented approach. The investigation shows the ability of the method to reliably simulate some important nonlinear viscoelastic phenomena such as saturation.
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Mechanical
Foams
Viscoelastic
Automotive
Nonlinear Material Models
LS-DYNA
Research Papers
October 08, 2014 | by DatapointLabs | views 4803
LS-DYNA software contains a wealth of material models that allow for the simulation of transient phenomena. The Matereality® CAE Modeler is a generalized pre-processor software used to convert material property data into material parameters for different material models used in CAE. In a continuation of previously presented work, we discuss the extension of the CAE Modeler software to commonly used material models beyond MAT_024. Software enhancements include advanced point picking to perform extrapolations beyond the tested data, as well as the ability to fine-tune the material models while scrutinizing the trends shown in the underlying raw data. Advanced modeling features include the ability to tune the rate dependency as well as the initial response. Additional material models that are quite complex and difficult to calibrate are supported, including those for hyperelastic and viscoelastic behavior. As before, the written material cards are directly readable into the LS-DYNA software, but now they can also be stored and catalogued in a material card library for later reuse.
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Plastics
Rubbers
Foams
Metals
High Speed Testing
Injection Molding
Nonlinear Material Models
Structural Analysis
LS-DYNA
Composites
Presentations
April 30, 2014 | by DatapointLabs | views 4604
The use of CAE in design decision-making has created a need for proven simulation accuracy. The two areas where simulation touches the ground are with material data and experimental verification and validation (V&V). Precise, well designed and quantitative experiments are key to ensure that the simulation initiates with correct material behavior. Similar validation experiments are needed to verify simulation and manage the risk associated with this predictive technology.
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Plastics
Rubbers
Foams
Metals
Automotive
Biomedical
Building Materials
Consumer Products
Energy and Petroleum
Material Supplier
Toys/Sporting Goods
Electonics/Electrical
Industrial Goods
CAE Vendor/Supplier
Mold Maker/Designer
Nonlinear Material Models
Structural Analysis
Abaqus
Composites
SIMULIA
Presentations
May 08, 2011 | by DatapointLabs | views 4922
DatapointLabs' TestPaks (material testing + model calibration + Abaqus input decks) for rate-dependent, hyperelastic, viscoelastic, NVH, and the use of Abaqus CAE Modeler to transform raw data into material cards will be presented. A representative from Idiada will present a case study explaining the use of DatapointLabs’ material data and TestPaks for simulation.
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Plastics
Rubbers
Foams
Metals
High Speed Testing
Nonlinear Material Models
Structural Analysis
Abaqus
Composites
SIMULIA
Presentations
September 23, 2010 | by Datapoint Newsletters | views 4735
DatapointLabs Joins TechNet Alliance. ANSYS Chaboche Model. CAE-INPUT Decks Now Available for ANSYS Polyflow. Foam Modeling in ANSYS.
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Foams
Metals
ANSYS
POLYFLOW Blow Molding
POLYFLOW Extrusion
POLYFLOW Thermoforming
Newsletters
July 21, 2010 | by DatapointLabs | views 4667
The limitations of modeling materials for simulation are discussed, including lack of clarity in material model requirements, gaps between the material data and the model to which it will be fitted, issues in obtaining pertinent properties, difficulties in parameter conversion (fitting), and preparation of input files for the software being used. Means to address these limitations are presented, including understanding the model completely, measuring the correct data with precision on the right material, selecting the best model for the data and ensuring the best fit of the model to the data, validating the model against a simple experiment, and following best practices to create an error-free input file.
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Plastics
Rubbers
Foams
Aerospace and Defense
Automotive
Biomedical
Consumer Products
Material Supplier
Toys/Sporting Goods
Electonics/Electrical
Industrial Goods
Packaging
Home Appliances
Presentations
April 13, 2009 | by DatapointLabs | views 4831
We seek to lay down a framework to help us understand the different behavioral classes of foams. Following a methodology that we previously applied to plastics, we will then attempt to propose the right LS-DYNA material models that best capture these behaviours. Guidelines for model selection will be presented as well as best practices for characterization. Limitations of existing material models will be discussed.
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Foams
Automotive
Consumer Products
Material Supplier
Packaging
Home Appliances
High Speed Testing
Nonlinear Material Models
Structural Analysis
LS-DYNA
Abaqus
ANSYS
MSC.DYTRAN
Research Papers
May 16, 2008 | by DatapointLabs | views 4984
We present a perspective on material modeling as applied to mold analysis requirements. Melt-solid transitions and the case for a unified material model are discussed, along with prediction of post-filling material behavior and shrinkage, and the impact of viscous heating on flow behavior and material degradation.
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Plastics
Rubbers
Foams
Metals
Aerospace and Defense
Automotive
Biomedical
Consumer Products
Energy and Petroleum
Electonics/Electrical
Industrial Goods
CAE Vendor/Supplier
Packaging
Home Appliances
Blow Molding
Extrusion
Injection Molding
Nonlinear Material Models
Moldflow
Composites
Presentations
Gels
Oils/Lubricants
Waxes
April 23, 2003 | by DatapointLabs | views 4477
This book covers some of the most significant techniques used in modern analytical technology to characterize plastic and composite materials.
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Plastics
Rubbers
Foams
Composites
March 13, 2001 | by DatapointLabs | views 4825
Hyperelastic models are used extensively in the finite element analysis of rubber and elastomers. These models need to be able to describe elastomeric behavior at large deformations and under different modes of deformation. In order to accomplish this daunting task, material models have been presented that can mathematically describe this behavior [1]. There are several in common use today, notably, the Mooney-Rivlin, Ogden and Arruda Boyce. Each of these has advantages that we will discuss in this article. Further, we will examine the applicability of a particular material model for a given modeling situation.
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Rubbers
Foams
Aerospace and Defense
Automotive
Biomedical
Nonlinear Material Models
Structural Analysis
Abaqus
ANSYS
SOLIDWORKS
MSC.MARC
NX Nastran
Research Papers
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