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Material Command

A Material command block allows you to specify a new material type and define all its properties. The command block format is:

Material (matid),(name),(type)
   (Property commands - one per line)
Done

where

The Material command should contain lines to define all the material properties. The various material types expect different properties. The required properties for each material type are given in sections about that material. Many properties are case insensitive, but some (especially newer ones) are case sensitive; it is best to match the case of the tables. Besides material property commands, the Material block can contain no other commands except conditional blocks.

Material Tables

The following tables list materials supported by NairnFEA or NairnMPM. The boxes in the table tell which code supports the materials. For 2D MPM, the first X means it can be used in plane stress MPM, the second is for plain strain MPM, and that last is for axisymmetric analyses. Materials that are in the code, but not define in the tables below, can usually be used by using the methods for development materials. Besides these materials, the Material command is also used to define traction law materials.

Linear Elastic Small Strain Materials

The materials in this section are all small-strain, linear elastic materials. They allow for large rotations.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
Isotropic 1 Linear elastic, isotropic XX X XX
Transverse 2 Linear elastic, transversely isotropic with unrotated axial direction in the z (or θ if axisymmetric) direction or x-y (or r-z if axisymmetric) plane of 2D analyses is the material's isotropic plane. XX X XX
Orthotropic 4 Linear elastic, orthotropic material XX X XX
Bistable 10 Elastic, isotropic material with two stable states and reversible or irreversible transitions between the two states X X X

Hyperelastic Materials

The materials in this section are designed to solve finite strain (or large deformation) problems. They are formulated using hyperelasticity methods

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
Mooney 8 Mooney-Rivlin, hyperelastic, isotropic material. Neo-Hookean and a rubbery materials is a special case of this material. X X XX
Neo-Hookean 28 An alternate isotropic, hyperelastic, neo-Hookean material. X X XX -
IdealGas
22 Ideal or non-ideal van der Waals Gas, as a hyperelastic material. - X XX
TaitLiquid
27 Newtonian liquid with Tait law for pressure dependence as a hyperelastic material. - X XX

Elastic-Plastic Small Strain Materials

The materials in this section are all small-strain, elastic-plastic materials. They account for large rotations. They handle plasticity by combining one of these materials with any compatible hardening law.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
IsoPlasticity 9 Small-strain elastic-plastic material to be used with a selected hardening law. X X XX
HillPlastic 15 Elastic-plastic orthotropic material with a Hill yield criterion and hardening - X XX

Softening Small Strain Materials

The materials in this section implement anisotropic damage mechanics as a method for emulating fracture mechanics through constitutive law model rather than explicit crack propagation.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
IsoSoftening 50 Small-strain isotropic material with anisotropic damage mechanics. X X XX
IsoPlasticSoftening 53 Small-strain isotropic material that combines plasticity with anisotropic damage mechanic. X X XX
TransIsoSoftening 51 Small-strain transversely-isotropic material with anisotropic damage mechanics and with unrotated axial direction in the z (or θ if axisymmetric) direction or x-y (or r-z if axisymmetric) plane of 2D analyses is the material's isotropic plane. - X XX
OrthoSoftening 54 Small-strain orthotropic material with anisotropic damage mechanics. - X X
OrthoPlasticSoftening 56 Small-strain orthotropic material that combines plasticity with anisotropic damage mechanics. - X X
IsoPhaseFieldSoftening 57 Small-strain isotropic material that use phase field methods to mode cracks by variational fracture mechanics. X X X
IsoDamageMechanics 58 Small-strain isotropic material that evolves damage using isotropic damage mechanics methods. X X X

Hyperelastic-Plastic Materials

The materials in this section are formulated within the framework of hyper elasticity formulation. They can handle plasticity by combining them with any compatible hardening law.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
HEIsotropic 21 An isotropic, hyperelastic-plastic material to be used with a selected hardening law. - X XX
HEMGEOSMaterial 25 or 17 Hyperelastic-plastic isotropic material using the Mie-Grüneisen equation of state to be used with a selected hardening law. - X XX
ClampedNeohookean 29 Isotropic, hyperelastic-plastic material with elongations limited to maximum strains. - X XX

Viscoelastic Materials

The materials in this section are viscoelastic materials materials.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
Viscoelastic 7 Linear viscoelastic material with sum of relaxation times X X XX
TIViscoelastic 5 Viscoelastic, transversely isotropic with unrotated axial direction in the z (or θ if axisymmetric) direction or x-y (or r-z if axisymmetric) plane of 2D analyses is the material's isotropic plane. X X XX

PhaseTransition Materials

The materials in this section model phase transitions between other materials.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
PhaseTransition 30 Models a first order transtion between a solid and a liquid. - X XX

Specialty Materials

The materials in this section have special uses.

Name#DescriptionNairnFEA2D NairnMPM3D NairnMPM
Interface 5 A definition of an imperfect interface X
Rigid 11 Not really a material, but useful for moving boundary conditions X X XX
Other Materials - See this section for method to use materials in the code engines that are not known to NairnFEAMPM. ???

Isotropic Material

For details see the OSUPDocs wiki. The properties are:

Transversely Isotropic Material

This material has the axial direction along the z axis and is isotropic in the x-y plane. Any other orientation is achieved by rotating from these initial orientations. Use the swapz property to move the axial direction into the 2D analysis plane. For more details see the OSUPDocs wiki. The properties are:

Orthotropic Material

An orthotropic material has different properties in all three directions. You can enter the properties in the x, y, and z direction. Any other orientation is achieved by rotating from these initial orientations. For more details see the OSUPDocs wiki. The properties are:

Interface Material

An interface material is used to model imperfect interfaces. This material is used in NairnFEA only. It can only be used to link two separate areas with normal solid elements. The edges of the areas most overlap with all nodes and elements at identical locations. The two interface properties are:

See Imperfect Interface Elements for more information on modeling imperfect interfaces in NairnFEA.

Linear Viscoelastic Material

This material is a small-strain, linear viscoelastic material with time-dependent bulk and shear moduli given by a sums of relaxation times. The pressure law can use small strain methods (with time-dependent bulk modulus) or large-deformation Mie-Grüneisen equation of state (MGEOS) (with time-independent but non-linear elastic bulk modulus). The input properties are:

The relaxation shear modulus is given by G(t) = G0 + G1exp(-t/tau1) + G2exp(-t/tau2) + ... + Gntausexp(-t/tauntaus) where the Gk and tauk are matched in the order they are supplied. The relaxation bulk modulus when pressureLaw is 0 is given by K(t) = K + K1exp(-t/tauK1) + K2exp(-t/tauK2) + ... + KntausKexp(-t/tauKntausK) where the Kk and tauKk are matched in the order they are supplied. For more details see the OSUPDocs wiki.

This material can be used in plane stress analysis, but only if pressureLaw=0 and artificial visocity is not used.

History Data for Linear Viscoelastic, Isotropic Materials

You can archive total volume change (J) and residual free expansion volume (Jres) in history variables 1 and 2 (Jres, but only when using MGEOS traction law. This material also tracks internal viscoelastic variables. These can be archived, but may not provide much useful information. They start in number 3 when using MGEOS traction law or 1 if when using small-stress pressure law.

Transversely Isotropic Viscoelastic Material

This material is a small-strain, linear viscoelastic material with five time-dependent moduli each given by a sum of relaxation times.The axial direction is along the z axis and the material is isotropic in the x-y plane. Any other orientation is achieved by rotating from these initial orientations. Use the swapz property to move the axial direction into the 2D analysis plane. The input properties are:

Each relaxation modulus is given by P(t) = P0 + P1exp(-t/tau1) + P2exp(-t/tau2) + ... + Pntausexp(-t/tauntaus) when the Pk and tauk are matched in the order they are supplied. For each of five properties, enter the steady value (which becomes P0) and follow that by series of Pk and tauk values For more details see the OSUPDocs wiki.

History Data for Transversely Isotropic Viscoelastic Materials

This material tracks numerous internal viscoelastic variables. They can be archived, but may not provide much useful information.

Mooney-Rivlin Hyperelastic Material

The material type is an isotropic, hyperelastic material. The stresses are defined from the strain energy. For mechanics details see the OSUPDocs wiki. The properties are:

This material is identical to an isotropic material at low strain with shear modulus given by G = G1+G2 and bulk modulus equal to K. A neo-Hookean material is a special case of a Mooney-Rivlin material by setting G2 = 0. You have to either either K and G1 OR E and nu. If E and nu are entered, K is found from E/(3*(1-2*nu)) and G1 from E/(2*(1+nu)) - G2 (in other words G1+G2 is the low strain shear modulus).

History Data for Mooney-Rivlin Material

This material use history #1 to store the volumetric strain (i.e., the determinant of the deformation gradient). The total strain, which is equal to the elastic strain, is stored in the elastic strain variable and the plastic strain stores the left Cauchy Green tensor.

Neo-Hookean Material

The material type is an isotropic, hyperelastic material. The stresses are defined from the strain energy. For mechanics details see the OSUPDocs wiki. The properties are:

From the first five properties, you must enter K and G, Lame and G, OR E and nu. If you enter any other combination or more than two, an error will result. This material is identical to an isotropic material at low strain with the entered mechanical properties.

History Data for Neo-Hookean Material

This material uses history #1 to store the volumetric strain (i.e., the determinant of the deformation gradient). The total strain, which is equal to the elastic strain, is stored in the elastic strain variable and the plastic strain stores the left Cauchy Green tensor.

Clamped Neo-Hookean Material

The material type is a large-deformation, isotropic, hyperelastic material. It yields when the tensile and/or compression elongation reaches critical values of 1+θs and/or 1-θc. The underlying elastic component of the deformation is a neo-Hookean material. After yielding, the mechanical properties soften in tension or harden in compression according to an entered hardening coefficient. The material properties are

History Data for Clamped Neo-Hookean Material

  1. The volumetric ratio or J = V/V0 (i.e., the determinant of the deformation gradient)
  2. The plastic volumetric ratio or JP = J/JE where JE is determinant of the elastic deformation gradient)

The total strain is stored in the elastic strain variable while the plastic strain stores the left Cauchy Green tensor. You have to archive both strain and plastic strain for the visualization to be able to plot elastic and plastic strains.

Ideal Gas Material

The material type is an ideal gas or a non-ideal van der Walls gas, implemented as a large-deformation, isotropic, hyperelastic material at finite deformations. The detailed documentation is currently only available on the OSUPDocs wiki.

Tait Liquid

The material type is an Newtonian liquid using the Tait equation for dependence of pressure on temperature and volume. It is implemented as a large-deformation, isotropic, hyperelastic material at finite deformations (see OSUPDocs wiki for implementation details). The properties are:

If one viscosity is given and no logshearrate, the material has constant viscosity. If multiple logshearrate and viscosity commands are used, each pair defines points for piecewise linear representation of viscosity as a function of log shear rate. You must enter an equal number of logshearrate and viscosity commands with monotonically increasing shear rates. The liquid's viscosity will be interpolated within the provided points. Shear rates below the minimum or above the maximum provided shear rates will be equal to the viscosity at the minimum or maximum shear rate, respectively.

History Data for Tait Liquid

The following history variables are stored:

  1. Volumetric strain ratio J = V/V0 (i.e., the determinant of the deformation gradient).
  2. Volumetric residual strain ratio Jres.
  3. Shear rate.

Isotropic Elastic-Plastic Material

This material is small-strain, isotropic material with plasticity. The plasticity response is handled by selecting a hardening law response. The properties are:

History Data for Isotropic, Elastic-Plastic Material

The material has none, but the hardening law will have at least one.

In particle properties, the "strain" will be the total strain and the "plastic strain" will have the plastic strain. The total strain is the sum of elastic and plastic strains. You have to archive both strain and plastic strain for the visualization to be able to plot elastic and plastic strains.

Isotropic, Hyperelastic-Plastic Material

The material is a large-deformation, isotropic, hyperelastic-plastic material. For mechanics details see the OSUPDocs wiki. The properties are:

History Data for Isotropic Hyperelastic-Plastic Materials

The first history variables are determined by the hardening law. After those variables, the next history variable stores the volumetric strain (i.e., the determinant of the deformation gradient, [F]). The total strain is stored in the elastic strain variable while the plastic strain stores the plastic. You have to archive both strain and plastic strain for the visualization to be able to plot elastic and plastic strains.

Mie-Grüneisen Equation of State Materials

This hyperelastic material uses large deformation theory for pressure response and for shear and yielding. The pressure is determined by the Mie-Grüneisen equation of state. The yielding process can be selected using any hardening law. The properties are:

In this material, the pressure is related to the volumetric compression strain (x = -ΔV/V0) by the Mie-Grüneisen equation of state. When x>0, the material is in compression and pressure is

P = ρ0C02x(1 - 0.5 γ0 x) / (1 - S1x - S2x2 - S3x3)2 + ρ0γ0e

where e is the internal energy made up of elastic, plastic, and heat energy. The heat energy depends on temperature relative to a reference temperature; the reference temperature is set using the StressFreeTemp command. When x<0, the material is in tension and the pressure changes to

P = ρ0C02x + ρ0γ0e

The first term is bulk modulus terms with the low-strain bulk modulus being ρ0C02. For more details see the OSUPDocs wiki.

This equation of state automatically handles thermal expansion by inclusion of thermal energy in the internal energy. You do not need to enter a thermal expansion coefficient, but you do need to enter heat capacity Cv to get the thermal expansion correctly.

History Data for Mie-Grüneisen Equation of State Material

The first history variables are determined by the hardening law. After those variables, the next history variable stores the volumetric strain (i.e., the determinant of the deformation gradient, [F]). The total strain is stored in the elastic strain variable, while the plastic strain stores the elastic, left Cauchy Green tensor. You have to archive both strain and plastic strain for the visualization to be able to plot elastic and plastic strains.

Hill Plastic Material

This material is an orthotropic material but can yield in response to the the anisotropic Hill yield criterion (see below), which allows yielding at different stresses when loaded in different directions. Enter the underlying orthotropic material properties and then enter the direction-dependent yield stresses. Any omitted yield stress will be assumed to be infinite (i.e., no yielding in that direction). The properties are:

The anisotropic yield criterion is

[ F(σyy - σzz)2 + G(σxx - σzz)2 + H(σyy - σxx)2 + 2Lτyz2 + 2Mτxz2 + 2Nτxy2 ]1/2 - H(α)

where H(α) is a hardening law as a function of cumulative plastic strain and σxx, σyy, σzz, τyz, τxz, and τxy are stresses in the material axis system after rotation from the analysis coordinates. The constant are determined by the yield stresses:

2F = (1/yldyy2) + (1/yldzz2) - (1/yldxx2)
2G = (1/yldxx2) + (1/yldzz2) - (1/yldyy2)
2H = (1/yldxx2) + (1/yldyy2) - (1/yldzz2)
2L = (1/yldyz2)
2M = (1/yldxz2)
2N = (1/yldxy2)

The τyz and τxz terms and their yield stresses are not needed for 2D analyses.

If nhard>0, the hardning law is H(α) = 1 + Khard*αnhard, but if nhard<0, the hardening law is changed to H(α) = (1 + Khard*α)nhard. If exphard is provided instead, the hardening law is exponential or H(α) = 1 + (Khard/exphard)*(1-exp(-exphard*α)). If both nhard and exphard are provided, the last one provided will determine the hardening law. If alphaMax is provided exponential hardening converts to linear softening using the final slope of the exponential hardening law (this parameter is used to prevent exponential hardening from decaying to elastic-plastic response).

For more details see the OSUPDocs wiki.

History Data for Hill Plastic material

  1. The cumulative equivalent plastic strain, α, defined as the sum of sqrt(2/3)||dεp||.

In particle properties, the "strain" will be the total strain and the "plastic strain" will have the plastic strain. The total strain is the sum of elastic and plastic strains. You have to archive both strain and plastic strain for the visualization to be able to plot elastic and plastic strains.

Bistable Isotropic Material

This material has two isotopic states. The first state (state "0") must be fully defined. Any property omitted for the second state (state "d") will be assumed to be identical to the first state. The mechanical and transport properties in the two states are set with:

The transition between the two states is determined either by a dilation rule, a distortion rule, or a Von Mises stress rule (see transition property). In dilation rule, the transition occurs when the volumetric strain reaches the entered critical value. In distortion rule, the transition occurs when the second strain invariant reaches a critical value. By a Von Mises stress rule, the transition occurs when the Von Mises stress reaches a critical value. When using a dilation rule, the new stress-strain relation can include a changed offset in volumetric strain corresponding to stress-free conditions at a non-zero dilation relative to the initial state (see DeltaVOffset property). This change normally leads to an instantaneous change in stress upon transition. When using a distortion or Von Mises stress rule, the offset is ignored and the change is only a change in slope of mechanical properties. For more details see the OSUPDocs wiki. The properties determining the transition are:

History Data for Bistable, Isotropic Elastic Materials

History variable 1 will be 0 for the initial state and 1 for the deformed state after a transition. This variable can be archived as history1.

Isotropic, Small-Strain Material with Anisotropic Damage

The material is an isotropic, small strain material and currently only in OSParticulas. Once damage initiates (using any appropriate initiation law), the material develops a crack and propagates damage using anisotropic damage mechanics. The damage process is controlled by available softening laws. For more details see the OSUPDocs wiki.The properties are:

The particle plastic strain will archive the total cracking strain in the global axis system. The plastic energy will archive the total amount of energy released by damage to the particle.

History Data for Isotropic, Small-Strain Materials with Anisotropic Damage

  1. 0.1 to indicate undamaged, 0.9 or 1.1 to indicate damage propagation following initiation by tensile failure (if 0.9) or shear failure (if 1.1), and between 2 and 3 after failure by decohesion. After failure, the fraction energy dissipated by mode I damage is GI/Gtotal = h[1]-2.
  2. δn or the maximum normal cracking strain.
  3. δxy or the maximum x-y shear cracking strain.
  4. δxz or the maximum x-z cracking strain (for 3D cuboid only), but changed to mode I dissipated energy for all other cases.
  5. dn or damage variable for normal loading.
  6. dxy or damage variable for x-y shear loading.
  7. dxz or damage variable for x-z shear loading (for 3D cuboid only), but changed to mode II dissipated energy for all other cases.
  8. For 2D it is cos(α), but for 3D it is Euler angle α.
  9. For 2D it is sin(α), but for 3D it is Euler angle β.
  10. For 2D it is not used, but for 3D it is Euler angle γ.
  11. Ac/Vp where Ac is crack area within the particle and Vp is particle volume.
  12. Relative strength derived at the start by coefVariation and coefVariation propertiesMode.
  13. Relative toughness derived at the start by coefVariation and coefVariation propertiesMode.

History variables 8-10 are storing Euler angles α, β, and γ (in radians) for a Z-Y-Z rotation scheme; only α is needed for 2D and it is stored as cos(α) and sin(α) instead of as angles.

Isotropic, Plastic, Small-Strain Material with Anisotropic Damage

This material is an isotropic, elastic-plastic material that can also develop aniostropic damage. For more details see the OSUPDocs wiki. The properties are:

The particle plastic strain will archive the sum of plastic and cracking strain in the global axis system. The plastic energy will archive the total amount of energy released by plsticity or by damage to the particle.

History Data for Isotropic, Plastic, Small-Strain Materials with Anisotropic Damage

Transversely isotropic, Small-Strain Material with Anisotropic Damage

This material is a transversely-isotropic elastic materials that can also develop aniostropic damage. The detailed documentation is currently only available on OSUPDocs wiki.

Orthotropic, Small-Strain Material with Anisotropic Damage

This material is an orthotropic, elastic material that can also develop aniostropic damage. The detailed documentation is currently only available on OSUPDocs wiki.

Orthotropic, Small-Strain Material with Anisotropic Damage and Plasticity

This material is an orthotropic, elastic-plastic material that can also develop aniostropic damage. The detailed documentation is currently only available on OSUPDocs wiki.

Isotropic, Small-Strain Material using Phase Field Fracture

This material is an isotropic that evolves damage using variational mechanics. It requires being run along with methods for phase field calculations. The detailed documentation is currently only available on OSUPDocs wiki. In brief, the properties are:

History Data for Isotropic, Plastic, Small-Strain Materials with Anisotropic Damage

  1. Maximum energy history term that provides source terms for phase field evolution
  2. Damage state equation to 0 if not failed and 1 if failure (''i.e.'', phase value has reached 1)
  3. Current phase field value
  4. Change in phase field since the last time step. It is used in constitutive law modeled and is scaled by 0.5 when using USAVG method.

Isotropic, Small-Strain Material with Isotropic Damage and Plasticity

This material is an isotropic material that evolves damage using isotropic damage mechanics. The detailed documentation is currently only available on OSUPDocs wiki. In brief, the properties are:

An alternative to randomly varying strength or toughness using coefVariation and coefVariationMode properties is to set the relative values using a PropertyRamp Custom Task. For example, a BMP image of a Gaussian random field could assign relative strengths or toughness with random variations that include spatial correlations.

First Order Phase Transition Material

The material models a phase transtition between a solid phase and a liquid phase. It is currently only in OSParticulas. The properties are:

History Data for First Order Phase Transition Material

  1. The current phase with 0 for solid and 1 for liquid
  2. The particle's melting temperature (which is randomized using Tsigma>0).

History numbers of n>2 will return history number n-2 of the solid phase (if it has that history number.

Rigid Material

This type of material is actually two materials in one, depending on the value for its direction property (which is defined below):

  1. If direction is 0 through 7, the material is not really a material and points that are this type of rigid material will not really be part of the MPM analysis. These rigid material points are used to set boundary conditions on the grid that move with the particles. As the rigid material points move through the grid, all nodes connected to those points will be assigned grid-based boundary conditions for the selected particle properties of velocity, temperature, and/or concentration. To have the boundary condition vary in time, time step, and position, use the settingFunction(2)(3) and valueFunction properties below to set the value rather than using the initial particle properties to pick a constant value.
  2. If direction is 8, the material will correspond to actual material points that moves through the analysis. Since they are rigid, they will move with their prescribed velocity. They will interact with other material points only through multimaterial contact or imperfect interface laws and thus this type of rigid material can only be used in multimaterial mode MPM calculations.

For more details and these two types of rigid materials, see the OSUPdocs wiki. The properties are:

Development Materials

The code engines may provide materials that can be used but are not known to NairnFEAMPM. For example, a common way others can contribute to NairnMPM is to develop new material models. If such materials are created, you can fully use such materials in calculations run from NairnFEAMPM, even though this application may not know about them.

There are two kinds of development materials. The first are those fairly well developed and integrated in the source code distribution and its documentation. If you can read about a material in source code documentation (or on the OSUPDocs wiki), then it is likely you can enter it NairnFEAMPM just like fully-supported materials. In other words, you use a standard Material block with one property on each line. The only difference is that there is no help on such materials here. Instead, you have to refer to the OSUPDocs wiki for that material. For each property listed in that documentation, you replace the XML command with a NairnFEAMPM command where the NairnFEAMPM command is the XML tag (and it is case sensitive) and the first (and only) argument is the value of the XML tag. For example to enter a property documented as "<S1>1.35</S2>", you would define it using "S1 1.25".

The second kind of development materials are those developed by third parties without any parallel modifications to NairnFEAMPM. These types of materials can still be used, but you have to enter the material properties using XML commands rather than built-in input commands, which is done by using the XMLData command. When using the XMLData command, you need to define a material ID that can be referenced by other input commands in the commands file. An example of such a defined material is

XMLData Material,"MGSCGL ID"
  <Material Type="17" Name="Tungsten">
    <C0>4004</C0>
    <S1>1.35</S1>
    <S2>0</S2>
    <gamma0>1.64</gamma0>
    <G>160000</G>
    <rho>19.256</rho>
    <hardening>SCGL</hardening>
    <yield>2200</yield>
    <Cv>134</Cv>
    <GPpG0>0.01e-3</GPpG0>
    <GTpG0>-2.2e-4</GTpG0>
    <yieldMax>4000</yieldMax>
    <betahard>7.7</betahard>
    <nhard>0.13</nhard>
  </Material>
EndXMLData

The "MGSCGL ID" in the first line defines the material's ID. The XML commands contained within the XMLData command define the material by using code engine methods.

Common Material Properties

The following material properties are common to all types of materials, although not used by all materials. These properties are only used in MPM analyses.

Basic Properties

These are basic material properties

Fracture Toughness Properties

These properties set material properties that determine the fracture toughness of the material and control various aspects of crack propagation. Note that whether or not the properties are used depends on the selected criterion for crack growth.

Crack Propagation Properties

The criterion, direction, and traction properties (and the analogous alternate propagation properties) are set with following commands

Contact Properties

These commands allow custom contact properties for each material pair in multimaterial mode MPM:

Artificial Viscosity

Poroelasticity Properties

Some materials support poroelasticity calculations and the properties in this section control pore pressure flow between particles and coupling between stress and strain and pore pressure. The properties to use depend on symmetry of the parent material.

Isotropic Poroelasticity Properties

Transversely Isotropic Poroelasticity Properties

Orthotropic Poroelasticity Properties