strengthening the materials core of manufacturing enterprises

Posts in Category: 'Rubbers'


The Role of Materials in Simulation-Driven Product Development

DatapointLabs Technical Center for Materials has a mission to strengthen the materials core of manufacturing enterprises by facilitating the use of new materials, novel manufacturing processes, and simulation-based product development. A whole-process approach is needed to address the role of materials in this context.

...read full post

Mechanical Plastics Rubbers Metals Hyperelastic Nonlinear Material Models Structural Analysis ANSYS Validation 3D Printing Matereality Materials Information Management


Mid-Stage Validation as a Process Step in Simulation V&V

Physically accurate simulation is a requirement for initiatives such as late-stage prototyping, additive manufacturing and digital twinning. The use of mid-stage validation has been shown to be a valuable tool to measure solver accuracy prior to use in simulation. Factors such as simulation settings, element type, mesh size, choice of material model, the material model parameter conversion process, quality and suitability of material property data used can all be evaluated. These validations do not use real-life parts, but instead use carefully designed standardized geometries in a controlled physical test that probes the accuracy of the simulation. With this a priori knowledge, it is possible to make meaningful design decisions. Confidence is gained that the simulation replicates real-life physical behavior. We present three case studies using different solvers and materials, which illustrate the broad applicability of this technique.

...read full post

Mechanical Plastics Rubbers Metals Structural Analysis LS-DYNA Abaqus ANSYS Research Papers Presentations Validation 3D Printing


Datapoint Newsletter: Winter '17, Volume 23.1

New test capabilities, Matereality v10.2, upcoming presentations

...read full post

Mechanical Plastics Rubbers Hyperelastic Visco-elastic Rate Dependency High Speed Testing Structural Analysis Composites Newsletters Validation


Datapoint Newsletter: Fall '16, Volume 22.4

CAETestBench Validations; Matereality Enterprise Workflows; Latest Publications Available on Knowmats

...read full post

Plastics Rubbers Metals Hyperelastic Plasticity Rate Dependency Automotive Nonlinear Material Models LS-DYNA Abaqus ANSYS RADIOSS Newsletters Validation 3D Printing


Workshop: Testing, Modeling and Validation for Plastics & Rubber Simulation in ANSYS

Plastics exhibit non-linear viscoelastic behavior followed by a combination of deviatoric and volumetric plastic deformation until failure. Capturing these phenomena correctly in simulation presents a challenge because of limitations in commonly used material models. We follow an approach where we outline the general behavioral phenomena, then prescribe material models for handling different phases of plastics deformation. Edge cases will then be covered to complete the picture. Topics to be addressed include: Using elasto-plasticity; When to use hyperelasticity; Brittle polymers – filled plastics; Failure modes to consider; Criteria for survival; Choosing materials; Spatial non-isotropy from injection molding; Importance of residual stress; Visco-elastic and creep effects; Strain-rate effects for drop test and crash simulations; Fitting material data to FEA material models; The use of mid-stage validation as a tool to confirm the quality of simulation before use in real-life applications.

...read full post

Density Rheology Thermal Mechanical Plastics Rubbers Hyperelastic Visco-elastic Plasticity Rate Dependency Yielding/Failure analysis Injection Molding Structural Analysis ANSYS Presentations Validation


Determination and Use of Material Properties for Finite Element Analysis: Book Review

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.

...read full post

Mechanical Plastics Rubbers Foams Metals Hyperelastic Visco-elastic 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 RADIOSS SIMULIA Book Review


Ejection system design: Optimization with SIGMASOFT Virtual Molding

As the demand for functional integration and the need of design differentiation in manufactured products increase, the complexity of plastic parts increases as well; thus some previous knowledge on effective ejection systems becomes insufficient and the challenges in the design of ejection systems grow consistently.

...read full post

Rheology Plastics Rubbers Visco-elastic Automotive Biomedical Injection Molding SIGMASOFT Newsletters


Cold Runner Design - Getting the whole picture matters

The profitability of a molded rubber product depends to a large extent on the mold efficiency. To achieve the maximum productivity, besides the larges possible number of cavities it is desirable to minimize the rubber consumption and to produce parts without defects.

...read full post

Rheology Rubbers Automotive Biomedical Injection Molding SIGMASOFT Newsletters


A Simplified Approach for Strain-Rate Dependent Hyperelastic Materials with Damage

"Simulation of rubber-like materials is usually based on hyperelasticity. If strain-rate dependency has to be considered viscous dampers are added to the rheological model. A disadvantage of such a description is timeconsuming parameter identification associated with the damping constants. In this paper, a tabulated formulation is presented which allows fast generation of input data based on uniaxial static and dynamic tensile tests at different strain rates. Unloading, i.e. forming of a hysteresis, can also be modeled easily based on a damage formulation. We show the theoretical background and algorithmic setup of our model which has been implemented in the explicit solver LS-DYNA [1]-[3]. Apart from purely numerical examples, the validation of a soft and a hard rubber under loading and subsequent unloading at different strain rates is shown."

...read full post

Mechanical Rubbers Hyperelastic Rate Dependency Yielding/Failure analysis Automotive High Speed Testing LS-DYNA Research Papers


A Simplified Approach to the Simulation of Rubber-like Materials under Dynamic Loading

"The simulation of rubber materials is becoming increasingly important in automotive crashworthiness simulations. Although highly sophisticated material laws are available in LS-DYNA to model rubber parts, the determination of material properties can be non-trivial and time consuming. In many applications, the rubber component is mainly loaded uniaxially at rather high strain rates. In this paper a simplified material model for rubber is presented allowing for a fast generation of input data based on uniaxial static and dynamic test data."

...read full post

Mechanical Rubbers Hyperelastic Rate Dependency Automotive High Speed Testing LS-DYNA Research Papers


Software for Creating LS-DYNA Material Model Parameters from Test Data 

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.

...read full post

Plastics Rubbers Foams Metals High Speed Testing Injection Molding Nonlinear Material Models Structural Analysis LS-DYNA Composites Presentations


Providing an Experimental Basis in Support of FEA 

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.

...read full post

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


Datapoint Newsletter: Winter '12, Volume 18.1

Expanded Mechanical Test Capabilities.

...read full post

Mechanical Rubbers Newsletters


Material Parameter Calibration Services for Abaqus Non-Linear Material Models

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.

...read full post

Plastics Rubbers Foams Metals High Speed Testing Nonlinear Material Models Structural Analysis Abaqus Composites SIMULIA Presentations


Understanding and Coping with Material Modeling Limitations in FEA 

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.

...read full post

Plastics Rubbers Foams Aerospace and Defense Automotive Biomedical Consumer Products Material Supplier Toys/Sporting Goods Electonics/Electrical Industrial Goods Packaging Home Appliances Presentations


Characterization of Damage in Hyperelastic Materials Using Standard Test Methods and Abaqus

Over the past couple of decades, standard test methods and material models have existed for rubber-like materials. These materials were classified under the category of Hyperelastic materials. Well established physical test methods and computational procedures exist for the characterization of the material behavior in tension, compression, shear volumetric response, tear strength etc. However, effective modeling of the fracture behavior of hyperelastic materials using finite element techniques is very challenging. In this paper, we make an attempt to demonstrate the use of such standard test methods and the applicability of such test data for performing finite element analyses of complex nonlinear problems using Abaqus. Our goal is to demonstrate the effective use of standard physical test data to model multi-axial loading situations and fracture of hyperelastic materials through tear tests and indentation test simulations.

...read full post

Rubbers Material Supplier Industrial Goods Nonlinear Material Models Structural Analysis Abaqus Research Papers


Datapoint Newsletter: Spring '09, Volume 15.1

DatapointLabs Featured in Technical Conferences.

...read full post

Plastics Rubbers Foams Hyperelastic High Speed Testing Nonlinear Material Models LS-DYNA Abaqus Newsletters


Material Modeling of Soft Material for Non-linear NVH 

Abaqus’ Non-linear NVH capability permits the capture of material behavior of rubber seals and bushings, plastic parts and foam inserts which have a significant influence on the simulation. In this presentation, we discuss material calibration procedures for this application.

...read full post

Plastics Rubbers Automotive Building Materials Material Supplier Nonlinear Material Models Structural Analysis Abaqus Presentations


Material Modeling and Mold Analysis 

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.

...read full post

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


Characterization and Modeling of Non-linear Behavior of Plastics 

A considerable amount of CAE today is devoted to the simulation of non-metallic materials, many of which exhibit non-linear behavior. However, most material models to date are still based on metals theory. This places severe restrictions on the proper description of their behavior in CAE. In this paper, we describe non-linear elastic behavior and its interrelationship with plastic behavior in plastics. Special attention is given to the differentiation between visco-elastic (recoverable) strain and plastic (non-recoverable) strain. The goal of this work is to have a material model for plastics that can describe both loading and unloading behavior accurately and provide an accurate measure of damage accumulation during complex loading operations.

...read full post

Plastics Rubbers Aerospace and Defense Automotive Biomedical Consumer Products Material Supplier Toys/Sporting Goods Packaging Home Appliances Nonlinear Material Models Structural Analysis Abaqus Research Papers


Handbook for Plastics Analysis

This book covers some of the most significant techniques used in modern analytical technology to characterize plastic and composite materials.

...read full post

Plastics Rubbers Foams Composites


Practical Issues in the Development and Implementation of Hyperelastic Models

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.

...read full post

Rubbers Foams Aerospace and Defense Automotive Biomedical Nonlinear Material Models Structural Analysis Abaqus ANSYS SolidWorks MSC.MARC NX Nastran Research Papers


Principles of Polymer Engineering, 2nd Edition: Book Review

This book presents a concise and easily readable introduction to polymer behavior for design and production engineers. It seeks to explain the behavior of plastics and rubber using a materials science framework, by relating observed phenomena to changes in morphological and molecular structure. This presents a powerful way for engineers to grasp the underlying factors that make polymers the complex materials that they are. The reader is encouraged to step away from using linear-elastic metals concepts when designing with plastics. The pitfalls of such simplifications are pointed out and guidelines are presented to aid the designer in adopting a non-linear approach.

...read full post

Plastics Rubbers Nonlinear Material Models Book Review