November 21, 2014 | by DatapointLabs | views 5170
Thermoplastic materials are one of the largest categories of materials to be injection molded. Simulation of the injection molding process requires sophisticated and exact material properties to be measured. This presentation will discuss the testing required to characterize a material for use in SIGMASOFT, as well as the significance of material model parameters. Differences in testing methodology for amorphous and semi-crystalline polymers will be covered, along with step-by-step implementation into the software to produce a successful injection molding simulation simulation.
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Plastics
Electonics/Electrical
Injection Molding
Nonlinear Material Models
Structural Analysis
SIGMASOFT
Presentations
July 22, 2015 | by Paul Du Bois | views 5152
"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."
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Mechanical
Rubbers
Hyperelastic
Rate Dependency
Yielding/Failure Analysis
Automotive
High Speed Testing
LS-DYNA
Research Papers
July 14, 2011 | by Datapoint Newsletters | views 5136
New Lab Space & Equipment
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Mechanical
Newsletters
April 06, 2012 | by Datapoint Newsletters | views 5134
Technical Note: On the Conditioning of Plastics Prior to Testing. Expansion of Conditioning Capabilities.
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Newsletters
June 17, 2008 | by Datapoint Newsletters | views 5121
New Tests and TestPaks. New Presentations On-line.
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LS-DYNA
Altair RADIOSS
VISI Flow
Newsletters
Validation
September 15, 2011 | by Datapoint Newsletters | views 5118
Expansion: New Lab Space, New TestPaks. DIGIMAT MX Reverse Engineering Update.
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Mechanical
DIGIMAT
PAM-COMFORT
Newsletters
July 27, 2015 | by Paul Du Bois | views 5106
"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
March 13, 2001 | by DatapointLabs | views 5104
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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