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Inspire Extrude Polymer
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Reference
Find information about material data blocks in GRF files.
Material Models
HyperXtrude associates each component with a material. Each material is defined inside the material data block in the GRF file.
Polymer Material Properties
HyperXtrude supports six different models to describe the constitutive behavior of polymers. The material models available in HyperXtrude are:
Criminale-Ericksen-Filbey Viscoelastic Model
In this model, the deviatoric part of the stress tensor is expressed as function of the viscosity and the normal stress coefficients.

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Inspire Extrude Metal
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Inspire Extrude Polymer
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- What is Inspire Extrude Polymer?
  Inspire Extrude Polymer offers an analysis tool for virtual testing, validation, correction and optimization of extrusion die designs.
- FAQs
  Find answers to Frequently Asked Questions from our users.
- Extrusion Analysis
  Setup and perform an Extrusion analysis.
- Tool Deflection Analysis
  Setup and perform a Tool Deflection analysis.
- Calibration Analysis
  Setup and perform a Calibration analysis.
- Reference
  Find information about material data blocks in GRF files.
  - Material Models
    HyperXtrude associates each component with a material. Each material is defined inside the material data block in the GRF file.
    - Assign Material properties
      This block of information is for assigning the material properties to each element MATID.This block also enables you to identify different regions of the mesh with a unique name so as to use it for post-processing or mesh adaptation. A single MATERIAL can be assigned to more than one MATID.
    - Fluid Material Properties
      The Fluid material type is a parameter used with the BEGIN MATERIAL data block.
    - Workpiece Material Properties
      The Workpiece material is used to describe the extrudate in metal extrusion. Typically, this material is applied to the components in the mesh that describe the negative volume created by the tool (such as, billet, pockets, feeder cavity, welding chamber, porthole etc.) Inside the user profile, we assign this material even to the boundary faces of the workpiece components. HyperXtrude supports the following constitutive models for metals:
    - Polymer Material Properties
      HyperXtrude supports six different models to describe the constitutive behavior of polymers. The material models available in HyperXtrude are:
      - Power Law Model
        This is a two parameter model and it is described by the following equation.
      - Spriggs Power Law Model
        This is a three-paramter model described by the following equation.
      - Carreau Yasuda Model
        Carreau Yasuda model is expressed by the following equation. This model has five parameters, zero shear viscosity, infinite shear viscosity, time constant, transition parameter, and power law exponent.
      - Cross Model
        Cross model is expressed by the following equation. This model has three parameters: consistency A, exponent n, and reference shear stress t*. Consistency is modified using the temperature dependent function a_T to introduce the effect of temperature on the computed viscosity.
      - Modified Cross Model
        Modified Cross model is expressed by the following equation. This model has three parameters: consistency A, exponent n, and reference shear stress t*. Consistency is modified using the temperature dependent function a_T to introduce the effect of temperature on the computed viscosity. There is a very subtle difference between Cross and Modified Cross model, this difference enables (by appropriate choice of parameters) one to easily set up Carreau-Yasuda model to mimic the modified Cross model.
      - Herschel Bulkley Model
        Regularized Herschel-Bulkley model is a four-parameter model and it is given by the following equation.
      - Criminale-Ericksen-Filbey Viscoelastic Model
        In this model, the deviatoric part of the stress tensor is expressed as function of the viscosity and the normal stress coefficients.
      - Temperature Dependence
        Viscosity is a strong function of temperature. HyperXtrude has five user options for specifying the temperature dependence of polymer viscosity. These options are:
    - Solid Material Properties
      The Solid material type is a parameter used with the BEGIN MATERIAL data block. This material must be used when solving conjugate heat transfer problems.
    - Tool Material Properties
      The Tool material type is similar to the Solid material type and is a parameter used with the BEGIN MATERIAL data block. This material must be used when solving conjugate heat transfer problems. For Tool, HyperXtrude allows you to specify the conductivity in the form of diagonal tensor.
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Criminale-Ericksen-Filbey Viscoelastic Model

In this model, the deviatoric part of the stress tensor is expressed as function of the viscosity and the normal stress coefficients.

This model can be used with any of the above mentioned non-Newtonian models and the specific model selected is used only to describe the viscosity of the material. The first and second normal stress coefficient functions are described as an exponential function of the computed shear rate. In this specific implementation, the second normal stress coefficient is implemented as a function of the first normal stress coefficient.


Parameter	Description	Units	Data Type	Typical Value
ViscoElasticModel	Two valid choices are “None” (default) and “CEF”	None	String	"CEF"
CEF_Coefficient1	Constant in the exponential function describing the first normal stress coefficient	Pa/s2	Constant	1.0e+04
CEF_Coefficeint2	Constant in the exponential function describing the second normal stress coefficient	Pa/s2	Constant	-.10
CEF_Exponent	Exponent in the function describing the first normal stress coefficient	None	Constant	-1.5