Elastic Modulus

Elastic modulus, E, (Young’s modulus). Can be temperature dependent.

Poisson Ratio

Poisson’s ratio (NU). Can be temperature dependent. Should be between -1.0 and 0.5.

Shear Modulus

Shear modulus (G). Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient

Thermal coefficient of expansion (A). Can be temperature dependent.

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

Elastic Modulus ii

Modulus of elasticity in 1-, 2-, and 3-directions. Can be temperature dependent.

Poisson Ratio ij

Poisson’s ratio for uniaxial loading in the three different directions. Can be temperature dependent.

Shear Modulus ij

In-plane and transverse shear moduli in ij planes. Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient ii

Thermal coefficients of expansion in the three directions. Can be temperature dependent.

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

Stiffness ij

Elements of the 6x6 symmetric material property matrix in the material coordinate system. Can be temperature dependent.

Density

Density (RHO). Can be temperature dependent.

Thermal Expansion Coefficient ij

Thermal coefficients of expansion. Can be temperature dependent.

Structural Damping Coefficient

Structural damping coefficient (GE). Can be temperature dependent.

Reference Temperature

Reference temperature (TREF).

Stress/Strain Curve

Defines the nonlinear elastic stress-strain curve. You must select a field from the listbox. It can be strain and/or temperature dependent. Tabular definition of the stress-strain curve via the Fields application using a material field of strain should follow the specifications as outlined by Nastran. The first point of the material field should be the origin and the second point must be at the initial yield point. This material curve is elastic, meaning that in both loading and unloading the material behavior follows the stress-strain curve as defined. It is not recommended that both nonlinear elastic and elastoplastic constitutive models be active or defined for the same material. For work hardening, use the Elastoplastic constitutive model. See the Nastran Quick Reference Guide for more details.

Tension/Compression TAB1

All data provided must reference a strain dependent field defining the test data. Please refer to the Nastran Quick Reference Guide for descriptions of each of these tabular inputs.

Equibiaxial Tension TAB2

Simple Shear Data TAB3

Pure Shear Data TAB4

Pure Volume Compression TABD

Distortional Deformation Coefficients, Aij

Material constants related to distortional deformation. The Order of the Polynomical determines the number of coefficients required as input.

Volumetric Deformation Coefficients, Di

Material constants related to volumetric deformation. The Order of the Polynomial determines the number of coefficients required as input.

Density RHO

Defines the mass density which is an optional property.

Volumetric Thermal Expansion Coefficient AV

Coefficient of volumetric thermal expansion.

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Structural Damping Coefficient GE

Structural damping element coefficient.

Strain Energy Function
C10, C01, C11, C20, C30

Strain energy densities as a function of the strain invariants in the material. May vary with temperature via a defined material field. This option consolidates several of the hyperelastic material models, including Neo-Hookean (C10 only), Mooney-Rivlin (C10 & C01), and Full Third Order Invariant (all coefficients).

Density RHO

Defines the mass density

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field.

Bulk Modulus K

Defines the Bulk Modulus.

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Structural Damping Coefficient GE

Structural damping element coefficient.

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

Defines the material mass density.

Coefficient of Thermal
Expansion

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Modulus k

in the Ogden equation. The number of moduli required as input is dependent on the Order of the Polynomial.

Exponent k

in the Ogden equation. The number of exponents required as input is dependent on the Order of the Polynomial.

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

Defines the material mass density.

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Modulus n

in the Foam equation. The number of moduli required as input is dependent on the Order of the Polynomial.

Deviatoric Exponent n

in the Foam equation. The number of exponents required as input is dependent on the Order of the Polynomial.

Volumetric Exponent n

in the Foam equation. The number of exponents required as input is dependent on the Order of the Polynomial.

NKT

Chain density times Boltzmann constant times temperature. May vary with temperature via a defined material field.

Chain Length

Average chemical chain cross length. May vary with temperature via a defined material field.

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

This defines the material mass density.

Thermal Expansion Coefficient

Defines the instantaneous coefficient of thermal expansion. This property is optional. May vary with temperature via a defined material field

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Tensile Modulus

Defines standard tension modulus (E). May vary with temperature via a defined material field.

Maximum 1st Invariant

Defines . May vary with temperature via a defined material field.

Bulk Modulus K

Defines the Bulk Modulus.

Density RHO

This defines the material mass density.

Coefficient of Thermal
Expansion

Defines the coefficient of thermal expansion.

Reference Temperature TREF

Defines the reference temperature for the thermal expansion coefficient.

Yield Function

Yield function (YF) criterion:

von Mises, Tresca, Mohr-Coulomb, & Drucker-Prager supported on MATS1 entry. All others are for SOL 600 and placed on the MATEP entry. SOL 400 only supports von Mises.

Hardening Rule

Hardening Rule (HR). These are Isotropic, Kinematic, and Combined isotropic and kinematic and are placed on the MATS1 entry or MATEP entry depending on solution sequence and yield function selected. Hardening rules Power Law, Rate Power Law, Johnson-Cook, Kumar are available when no Yield Function is specified. This is used for SOL 600 only on MATEP entry.

Strain Rate Method

Selects an option for strain-rate dependent yield stress used in SOL 600. Cowper-Symonds requires input of Denominator C and Inverse Exponent P.

Stress/Strain Curve

This data must reference a strain dependent field. It can also be temperature and strain rate dependent. LIMIT1 in MATS1 determined from supplied tabular field of stress-strain curve. Data is placed on TABLES1 entry.

Internal Friction Angle

Defined for Mohr-Coulomb and Drucker-Prager yield function placed on the MATS entry LIMIT2.

Yield Point

Stress at Yield

Initial yield stress.

Beta

Parameter beta for parabolic Mohr-Coulomb or Buyukozturk concrete models. Placed on the MATEP entry.

10th Cycle Yield Stress

Equivalent 10th cycle tensile yield stress for Oak Ridge National Labs models (ORNL). Placed on the MATEP entry.

Denominator C

Inverse Exponent P

Constants for the Cowper-Symonds strain rate method.

Coefficient A / B / C / Bi

Exponent M / N

Coefficient and exponent data for Power Law, Rate Power Law, Johnson-Cook, and Kumar hardening rules.

initial Strain Rate

Room Temperature

Melt Temperature

Additional data input for the Johnson-Cook hardening rule.

Yield Function

Yield function (YF) criterion:

von Mises, Tresca, Mohr-Coulomb, & Drucker-Prager supported on MATS1 entry.

Hardening Rule

Hardening Rule (HR). These are Isotropic, Kinematic, and Combined isotropic and kinematic and are placed on the MATS1 entry.

Strain Rate Method

No strain rate methods are available for the Hardening Slope data.

Hardening Slope

Work hardening slope (H) - slope of stress versus plastic strain. Defined in units of stress. For an elastic-perfectly plastic case, use the Perfectly Plastic data input option.

Internal Friction Angle

Defined for Mohr-Coulomb and Drucker-Prager yield function placed on the MATS entry LIMIT2.

Yield Point

Initial yield stress.

Yield Function

See the Stress / Strain Curve table above. All options are identical except there must be a yield function selected.

Hardening Rule

None are available since no hardening is possible for a perfectly plastic material.

Strain Rate Method

Piecewise linear or Cowper-Symonds are available.

Yield Point

Initial yield stress.

All other data input is described in the Stress/Strain Curve table above.

Yield Function

No yield functions are available as the material is defined as rigid and then plastic, so no yield is possible.

Hardening Rule

See the Stress / Strain Curve table above. Valid options are the Power Law, Power Rate Law, Johnson-Cook, Kumar, and Piecewise Linear.

Strain Rate Method

Piecewise linear or Cowper-Symonds are available only if the Piecewise Linear hardening rule is selected.

Stress/Strain Curve

Necessary only when not using one of the power law hardening rules (Piecewise-Linear). This data must reference a strain dependent field. It can also be temperature and strain rate dependent. LIMIT1 in MATS1 determined from supplied tabular field of stress-strain curve. Data is placed on TABLES1 entry.

All other data input is described in the Stress/Strain Curve table above. Rigid Plastic is only used in SOL 600 and only for isotropic materials.

Tension Stress Limit

Stress limits for tension, compression, and shear used to compute margins of safety in certain elements. They have no effect on the computational procedures.

Compression Stress Limit

Shear Stress Limit

Failure criteria for the isotropic and two-dimensional orthotropic and anisotropic materials appear in the ST, SC, and SS fields on MAT1 and MAT2 entries and the Xt, Xc, Yt, Yc, and S fields on the MAT8 entry.

Failure Limits

For 2D orthotropic on the MAT8 entry, the limits can be defined as stress or strain allowables. This is not applicable to isotropic and anisotropic materials.

Tension Stress Limit

Stress limits for tension, compression, and shear are the same as those defined for non-composite failure.

Compression Stress Limit

Shear Stress Limit

Bonding Shear Stress Limit

Allowable shear stress of the bonding material. SB field on the PCOMP entry.

Failure criteria for the isotropic and two-dimensional orthotropic and anisotropic materials appear in the ST, SC, and SS fields on MAT1 and MAT2 entries and the Xt, Xc, Yt, Yc, and S fields on the MAT8 entry unless composites are being used in which case the data is written to the PCOMP entry as necessary.

Progressive Failure Options

Progressive failure options are None, standard Progressive Failure, Gradual or Immediate selective progressive failure for SOL 600. SOL 400 does not support progressive failure models and will ignore this setting if set to anything other than None. Only failure indices are computed when no progressive failure is specified. Anisotropic materials do not support progressive failure.

Tension Stress Limit X / Y /Z
Tension Strain Limit X / Y / Z

Compression Stress Limit X / Y / Z
Compression Strain Limit X / Y / Z

Shear Stress Limit XY / YZ / ZX
Shear Strain Limit XY / YZ / ZX

Tension, compression, and shear stress or strain limits used in the Maximum Stress or Strain, Hill, Hoffman, and Tsai-Wu failure criteria.

Shear Stress Bond (SB)

Allowable shear stress of bonding material between layers for composites only. This is used in SOL 600 only and is ignored for SOL 400.

Failure Index

Failure index used for Hill, Hoffman, and Tsai-Wu criteria.

Interactive Strength XY / YZ / ZX

Interactive strength constants for specified plane used in the Tsai-Wu criterion.

Max Fiber / Matrix Tension
Max Fiber / Matrix Compression

Max Tape Fiber Tension
Max Tape Fiber Compression

Max 1st Fiber Tension / Compression
Max 2nd Cross Fiber Tension / Compression

Max Thickness Tension
Max Thickness Compression

Definable stress limits for Hashin, Puck, Hashin-Tape, and Hashin-Fiber criteria.

Layer Shear Strength
Transverse Shear Strength YZ / ZX

Shear stress limits for Hashing, Puck, Hashin-Tape, and Hashin-Fiber criteria.

Slope P12C / P12T / P23C / P23T of Fracture Envelope

Slopes of the failure envelope used in Puck failure criterion.

Deactivate Tension X / Y/ Z
Deactivate Compress X / Y / Z
Deactivate Shear XY / YZ / ZX

Deactivate Elements

Deactivate Fiber / Matrix Tension
Deactivate Fiber /Matrix Compression
Deactivate Matrix Tension
Deactivate Matrix Compression

If any value other than blank or 0.0 is entered for progressive failure options Gradual and Immediate, failed elements are deactivated (placed ICi fields in MATF entry). See the Nastran Quick Reference Guide for information.

Residual Stiffness Factor
Matrix Compression Factor
Shear Stiffness Factor
E33 Fiber Failure Factor
Shear Fiber Failure Factor

Reduction fractions or factors. Values can be between 0.0 and 1.0. Used only for Gradual or Immediate progressive failure modes (placed on Ai fields in MATF entry). See the Nastran Quick Reference Guide for more information.

Data defined by the use of this form to define the primary stiffness, primary damping, and secondary damping for a creep model with tabular input appears on the CREEP entry for non-SOL 600 runs. Only isotropic materials use this data input method.