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Posts in Category: 'Material Supplier'


Damage Modeling under Impact Loading in Talc-Filled Polypropylene Compounds

Topics covered: Damage in mineral filled polypropylene under impact conditions; damage modeling and parameter identification (prior art, LyondellBasell contributions, debate in the CAE community); experimental and numerical validation; next steps

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Mechanical Plastics Rate Dependency Yielding/Failure analysis Automotive Material Supplier High Speed Testing LS-DYNA Presentations


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.

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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


Using an Intermediate Validation Step to Increase CAE Confidence

Simulations contain assumptions and uncertainties that a designer must evaluate to obtain a measure of accuracy. The assumptions of the product design can be differentiated from the ones for the solver and material model through the use of a mid-stage validation. An open loop validation uses a controlled test on a standardized part to compare results from a simulation to the physical experiment. From the validation, confidence in the material model and solver is gained. In this study, the material properties of a polypropylene are tested to characterize for an *ELASTIC *PLASTIC model in ABAQUS. A validation of a quasi-static three-point bending experiment of a parallel ribbed plate is then performed and simulated. A comparison of the strain fields resulting from the complex stress state on the face of the ribs obtained by digital image correlation (DIC) vs. simulation is used to quantify the simulation's fidelity.

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Plastics Plasticity Automotive Biomedical Consumer Products Material Supplier Toys/Sporting Goods Furniture Packaging Home Appliances Nonlinear Material Models Structural Analysis Abaqus Research Papers Validation


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.

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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


The Use of Digital Image Correlation (DIC) and Strain Gauges to Validate Simulation 

As part of Cornell University's mechanical engineering curriculum and study of classical beam theory, an aluminium beam is deformed to a specific load. Theoretical strains are calculated at certain points along the beam using beam theory, and then verified by using strain gauges placed at these points on the beam. This experiment is then extended to simulation of the same test setup in simulation software, where strains are analyzed at the same points. Discrepancies between the simulation, theory, and strain gauge results have often plagued the test, especially when incorporating more complex beam design. Through use of digital image correlation (DIC) it is possible to pinpoint some of the problem areas in the beam analysis and provide a better understanding of the localized strains that occur at any point in the deformed beam. The use of DIC provides a full field validation of simulation data, rather than a single spot check that strain gauges can provide. This validation technique helps to eliminate error that is associated with strain gauge placement and the possibility of missing strain hot spots that can arise when analyzing complex deformations or geometries.

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Plastics Metals Aerospace and Defense Automotive Biomedical Building Materials Consumer Products Material Supplier Toys/Sporting Goods Electonics/Electrical Industrial Goods CAE Vendor/Supplier Mold Maker/Designer Structural Analysis ANSYS Presentations


Validating Simulation Using Digital Image Correlation 

There is interest in quantifying the differences between simulation and real life experimentation. This kind of work establishes a baseline for more complex simulations bringing a notion of traceability to the practice of CAE. We present the use of digital image correlation as a way to capture strain fields from component testing and compare these to simulation. Factors that are important in ensuring fidelity between simulation and experiment will be discussed.

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Plastics Aerospace and Defense Automotive Biomedical Material Supplier Electonics/Electrical CAE Vendor/Supplier 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.

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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


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.

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


A Robust Methodology to Calibrate Crash Material Models for Polymers

High strain rate material modelling of polymers for use in crash and drop testing has been plagued by a number of problems. These include poor quality and noisy data, material models unsuited to polymer behaviour and unclear material model calibration guidelines. The modelling of polymers is thus a risky proposition with a highly variable success rate. In previous work, we tackled each of the above problems individually. In this paper, we summarize and then proceed to present a material modelling strategy that can be applied for a wide variety of polymers.

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Mechanical Plastics Aerospace and Defense Automotive Consumer Products Material Supplier Industrial Goods Packaging Home Appliances High Speed Testing Nonlinear Material Models Structural Analysis LS-DYNA Abaqus ANSYS MSC.DYTRAN PAM-CRASH RADIOSS Research Papers


Selecting Material Models for the Simulation of Foams 

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


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.

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


Simulating Plastics in Drop and Crash Tests 

If you want a crash simulation involving plastics to yield useful results, it is important to model the material behavior appropriately. The high strain rates have a significant effect on the properties, and failure can be ductile or brittle in nature, depending on a number of factors.

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Plastics Aerospace and Defense Automotive Biomedical Consumer Products Material Supplier Toys/Sporting Goods Industrial Goods Packaging High Speed Testing Nonlinear Material Models Structural Analysis LS-DYNA Abaqus ANSYS MSC.DYTRAN PAM-CRASH RADIOSS Research Papers


Material Modeling Strategies for Crash and Drop Test Simulation

Many LS-DYNA models are used for plastics crash simulation. However, common models are not designed for plastics. We present best practices developed for adapting common models to plastics, as well as best testing protocols to generate clean, accurate rate-dependent data.

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Metals Aerospace and Defense Automotive Consumer Products Material Supplier Industrial Goods Packaging High Speed Testing Nonlinear Material Models Structural Analysis LS-DYNA Abaqus ANSYS MSC.DYTRAN PAM-CRASH Presentations


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.

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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


Methodology for Selection of Material Models for Plastics Impact Simulation 

The volume of plastics that are subjected to impact simulation has grown rapidly. In a previous paper, we discussed why different material models are needed to describe the highly varied behavior exhibited by these materials. In this paper, we cover the subject in more detail, exploring in depth, the nuances of commonly used LS-DYNA material models for plastics, covering important exceptions and criteria related to their use.

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Plastics Aerospace and Defense Automotive Consumer Products Material Supplier Industrial Goods Packaging Nonlinear Material Models Structural Analysis LS-DYNA Abaqus ANSYS PAM-CRASH RADIOSS Research Papers


A Novel Technique to Measure Tensile Properties of Plastics at High Strain Rates

High strain-rate properties have many applications in the simulation of automotive crash and product drop testing. These properties are difficult to measure. These difficulties result from inaccuracies in extensometry at high strain rates due to extensometer slippage and background noise due to the sudden increase in stress at the start of the test. To eliminate these inaccuracies we use an inferential technique that correlates strain to extension at low strain rates and show that this can be extended to measure strain at higher strain rates

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Mechanical Plastics Rate Dependency Aerospace and Defense Automotive Consumer Products Material Supplier Toys/Sporting Goods Packaging Home Appliances High Speed Testing Nonlinear Material Models Structural Analysis LS-DYNA Abaqus ANSYS MSC.DYTRAN PAM-CRASH Research Papers


Closing the Gap: Improving Solution Accuracy with Better Material Models 

We discuss open issues in material models for plastics and propose better means of acquiring the right material data for Moldflow simulations using current testing technologies.

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Plastics Material Supplier Mold Maker/Designer Injection Molding Moldflow Presentations


Material Models in Simulation, Part 3: New viscosity models 

We discuss developments in viscosity modeling. New models are not generalized, but are designed to predict expected trends for polymers and incorporate both Newtonian and shear-thinning behavior.

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Plastics Material Supplier Mold Maker/Designer Injection Molding Moldflow Presentations


Understanding the Role of Material Properties in Simulations, Part 2

We discuss material properties in injection molding simulations, including the definition of property requirements, identification of evaluation parameters, and the role of material properties at each stage of the injection molding process, from mold filling through cooling, post-filling and shrinkage/warpage considerations.

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Plastics Material Supplier Mold Maker/Designer Packaging Injection Molding Moldflow Moldex3D Cadmould C-MOLD Presentations


High Speed Stress Strain Material Properties as Inputs for the Simulation of Impact Situations

With the recent changes in the crashworthiness requirements for US automobiles for improved safety, design engineers are being challenged to design interior trim systems comprised of polymeric materials to meet these new impact requirements. Impact analysis programs are being used increasingly by designers to gain an insight into the final part performance during the design stage. Material models play a crucial role in these design simulations by representing the response of the material to an applied stimulus. In this work, we seek to develop novel test methods to generate high speed stress-strain properties of plastics, which can be used as input to structural analysis programs...

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Plastics Metals Aerospace and Defense Material Supplier Toys/Sporting Goods Packaging Home Appliances High Speed Testing Nonlinear Material Models Structural Analysis Thermoforming LS-DYNA Abaqus ANSYS MSC.DYTRAN PAM-CRASH Research Papers