Material Properties
View and edit thermal, rheological, mechanical, and PVT properties for materials.
Materials Database
Use the Materials Database tab on the Materials dialog to view the material properties of any material in Inspire Mold. Click Edit to modify a material's properties and save a custom version of the material on the My Materials tab. You can also Import and Export materials to and from the database.
To view a material's properties, select the Material Group and Name at the top of the Materials dialog:
Material Property  Description  

Material Group  Lists the materials available in the Materials Database.  
Material Name  Lists the common polymers available for the specified material group. 
Description of Material Data
The injection molding solver requires the material properties of the polymer, mold, mold insert, part insert, and fiber to be specified.
 Physical and thermal properties
 Equation of State  PVT data
 Rheological (constitutive) properties
 Mechanical properties
 Additive data
 Physical and thermal properties
 Mechanical properties
Data Format and Units
 The current version of the solver expects the material data in .json format,
 All parameters are input in SI units
Polymer Data
It is assumed that the polymer data is measured with its fillers and other additives.
Physical and Thermal Properties
Each property can be specified as a scalar or as a table when considering variations due to temperature changes. Review the properties on the Thermal tab for the specified material:
Material Property  Description 

Specific Heat  Specifies the heat energy required to increase the temperature of a unit
quantity J/(KgK). Specific heat of the polymer
can be specified as a scalar value or as a function of temperature in the form of a
table. Solver keyword: SPECIFIC_HEAT 
Conductivity (Thermal Conductivity)  Specifies the heat conductivity of the material
(W/mK). Thermal conductivity of the polymer
can be specified as a scalar value or as a function of temperature in the form of a
table. Solver keyword: CONDUCTIVITY 
Density  Specifies the density of the polymer melt at the reference temperature in
(kg/m^{3}). Melt density is assumed
to remain constant during the filling phase. During packing simulation, Tait 2phase
model for the equation of state is used to compute polymer density. Solver keyword: DENSITY 
Rhealogical Properties
The solver models the rheology of the polymer using generalized Newtonian models. Models currently available in the solver compute viscosity as a function of effective shear rate and temperature. All the constitutive models are set by defining an appropriate combination of : a) an empirical model relating viscosity with shear rate and b) the temperature dependence. Temperature dependence is denoted using the symbol α_{T}.
Review the properties on the Rhealogical tab for the specified material:
Material Property  Description 

Constitutive Model  Five models are included in the Materials Database. Select the model
appropriate for your material choice. Review the Exponent, Consistency and Relative
Shear Stress for your chosen model.

Temperature Dependence  Temperature dependency of the viscosity can be modeled through one of the
following ways. The chosen model is specified with the temperature dependence
parameter, which is set with an integer value from 0 to 3:

Miscellaneous  Review these parameters:

Fiber Info  Inlet fiber distribution is assumed to be random. Review the fiber content for
the specified material including:
Note: Some materials do not include fiber orientation data. To add this data,
edit an existing material and save it as a new material in the My Materials
tab.

Mechanical Properties
The solver uses Young's modulus, Poisson's ratio, and the thermal expansion coefficient to perform warpage calculations of the solidified part. Review the properties on the Mechanical tab for the specified material:
Material PropertyIsotropic Model  Description 

Young's Modulus  Young's modulus of a material is a measure of the resistance of the material to deformation when subjected to stress. It is a measure of stiffness of the material. Units: Pa Solver keyword: YOUNG_MODULUS. 
Poisson Ratio  Poisson's ratio is the ratio of lateral and longitudinal strain when subjected to uniaxial stress. Solver keyword: POISSON_RATIO 
Yield Stress 
Specifies the stress point at which the material deformation changes from elastic to plastic. Units: Pa 
Coefficient of Thermal Expansion 
The thermal expansion coefficient describes the extent of changes in the size of the object due to variation in temperature: Units: 1/K Solver keyword: COEFFICIENT_THERMAL_EXPANSION 
Equation of State  PVT Data
The pressurevolumetemperature (PVT) relationship is modeled using Tait's twophase equation of state. The PVT behavior of the polymer in both solid and melt state is described using 14 parameters. These parameters are indicated with letter b and with a numerical subscript (19) and a letter subscript (m=melt, s=solid). The following equations describe the equation of state and its parameters.
Parameters b_{5} to b_{9} are identical for both melt and solid. They are repeated for simplicity of the data file and structure of the code.
TAIT_PARAMETERS_MOLTEN_STATE = [b_{1m} , b_{2m}, b_{3m}, b_{4m}, b_{5}, b_{6}, b_{7}, b_{8}, b_{9}]
TAIT_PARAMETERS_SOLID_STATE = [b_{1s}, b_{2s}, b_{3s}, b_{4s}, b_{5}, b_{6}, b_{7}, b_{8}, b_{9}]
Database keywords: TAIT_PARAMETERS_MOLTEN_STATE, TAIT_PARAMETERS_SOLID_STATEProcessing Data
 Valid for semicrystalline materials
 The temperature at which the crystalline structures melt
 The solver does not use this. Will become useful when we implement crystallization kinetics
 Solver keyword: MELTING_TEMPERATURE
 The temperature at which material ceases to flow
 It is greater than Glass Transition Temperature
 Solver keyword: NO_FLOW_TEMPERATURE
 The temperature at which the part can be safely ejected
 Solver keyword: EJECTION_TEMPERATURE
 Recommended minimum mold temperature
 Solver keyword: MINIMUM_MOLD_TEMPERATURE
 Recommended maximum mold temperature
 Solver keyword: MAXIMUM_MOLD_TEMPERATURE
 Recommended minimum melt temperature
 Solver keyword: MINIMUM_MELT_TEMPERATURE
 Recommended maximum melt temperature
 Solver keyword: MAXIMUM_MELT_TEMPERATURE
 The absolute maximum allowed for the melt temperature at the inlet
 Solver keyword: ABSOLUTE_MAXIMUM_MELT_TEMPERATURE
Mold / Mold Insert / Part Insert Data
Reference Temperature: Reference Temperature at which the data is measured. Units: K

Solver keyword: REFERENCE_TEMPERATURE
 Density of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: kg/m^{3}
 Solver keyword: DENSITY
 Specific heat of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: J/(kgK)
 Solver keyword: SPECIFIC_HEAT
 Thermal conductivity of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: W/(mK)
 Solver keyword: CONDUCTIVITY
 Young's modulus of the material. Units: Pa
 Solver keyword: YOUNG_MODULUS
 Poisson's ratio of the material.
 Solver keyword: POISSON_RATIO
 The thermal expansion coefficient of the material. Units: 1/K
 Solver keyword: COEFFICIENT_THERMAL_EXPANSION
Fiber Material data  For Stress Analysis of the Molded Part
This data is independent of the polymer or the percentage of weight in the mix. This is the basic fiber material data.
 Reference Temperature at which the data is measured. Ideally it should be temperature at which the test is performed. Units: K

Solver keyword: REFERENCE_TEMPERARTURE
 Density of the fiber at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: kg/m^{3}
 Solver keyword: DENSITY
 Specific heat of the fiber at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: J/(kgK)
 Solver keyword: SPECIFIC_HEAT
 Thermal conductivity of the fiber at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: W/(mK)
 Solver keyword: CONDUCTIVITY
 Young's modulus of the fiber. Units: Pa
 Solver keyword: YOUNG_MODULUS
 Poisson's ratio of the fiber.
 Solver keyword: POISSON_RATIO
 The thermal expansion coefficient of the fiber. Units: 1/K
 Solver keyword: COEFFICIENT_THERMAL_EXPANSION
Base Polymer Data For Stress Analysis of the Molded Part
 Reference Temperature at which the data is measured. Units: K
 Solver keyword: REFERENCE_TEMPERATURE
 Density of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: kg/m^{3}
 Solver keyword: DENSITY
 Specific heat of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: J/(kgK)
 Solver keyword: SPECIFIC_HEAT
 Thermal conductivity of the material at reference temperature. Solver will also support a temperature dependent table in the place of a single value at the reference temperature. Units: W/(mK)
 Solver keyword: CONDUCTIVITY
 Young's modulus of the material. Units: Pa
 Solver keyword: YOUNG_MODULUS
 Poisson's ratio of the material.
 Solver keyword: POISSON_RATIO
 The thermal expansion coefficient of the material. Units: 1/K
 Solver keyword: COEFFICIENT_THERMAL_EXPANSION
Unit Summary
Data  Unit 

Density  kg/m^{3} 
Specific Heat  J/(kgK) 
Conductivity  W/(mK) 
Yield Stress  Pa 
Young Modulus  Pa 
Poisson Ratio   
Coefficient Thermal Expansion  1/K 
Reference Temperature  K 
Minimum Mold Temperature  K 
Maximum Mold Temperature  K 
Minimum Melt Temperature  K 
Maximum Melt Temperature  K 
Glass Transition Temperature  K 
No Flow Temperature  K 
Ejection Temperature  K 
Viscosity model:  
Modified Cross:   
Consistency  Pa.s 
Exponent   
Reference Shear stress (tau)  Pa 
Zero Shear Viscosity  Pa.s 
Infinite Shear Viscosity  Pa.s 
Min Strainrate Limit  1/s 
Max Strainrate Limit  1/s 
Temperature Dependence:  
WLF:  
Constant C1   
Constant C2  K 
Pressure Dependency D3  K/Pa 
Tait Parameters:


Filler Data:  
Fiber Percentage  Percentage of fiber in the melt by weight 
Fiber Minimum Length  m 
Fiber Maximum Length  m 
Fiber Average Diameter  m 