ProductsAbaqus/StandardAbaqus/ExplicitAbaqus/CAE
TypeModel data LevelModel
Abaqus/CAEProperty module
Defining damage initiation as a material property
Required parameters
- CRITERION
-
Set CRITERION=DUCTILE to specify a damage initiation criterion based on the ductile
failure strain.
Set CRITERION=FLD to specify a damage initiation criterion based on a forming
limit diagram.
Set CRITERION=FLSD to specify a damage initiation criterion based on a forming
limit stress diagram.
Set CRITERION=HASHIN to specify damage initiation criteria based on the Hashin
analysis.
Set CRITERION=HYSTERESIS ENERGY to specify damage initiation criteria based on the inelastic
hysteresis energy dissipated per stabilized cycle in a low-cycle fatigue
analysis.
Set CRITERION=JOHNSON COOK to specify a damage initiation criterion based on the
Johnson-Cook failure strain.
Set CRITERION=MAXE to specify a damage initiation criterion based on the maximum
nominal strain for cohesive elements or enriched elements.
Set CRITERION=MAXS to specify a damage initiation criterion based on the maximum
nominal stress criterion for cohesive elements or enriched elements.
Set CRITERION=MAXPE to specify a damage initiation criterion based on the maximum
principal strain for enriched elements.
Set CRITERION=MAXPS to specify a damage initiation criterion based on the maximum
principal stress criterion for enriched elements.
Set CRITERION=MK to specify a damage initiation criterion based on a
Marciniak-Kuczynski analysis.
Set CRITERION=MSFLD to specify a damage initiation criterion based on the
Müschenborn and Sonne forming limit diagram.
Set CRITERION=QUADE to specify a damage initiation based on the quadratic
separation-interaction criterion for cohesive elements or enriched elements.
Set CRITERION=QUADS to specify a damage initiation based on the quadratic
traction-interaction criterion for cohesive elements or enriched elements.
Set CRITERION=SHEAR to specify a damage initiation criterion based on the shear
failure strain.
Set CRITERION=USER to specify a user-defined damage initiation criterion for
enriched elements.
Optional parameters
- ALPHA
-
This parameter can be used only in conjunction with CRITERION=HASHIN.
Set this parameter equal to the value of the coefficient that will multiply
the shear contribution to the Hashin's fiber initiation criterion. The default
value is .
- ACCUMULATION POWER
- This parameter can be used only with CRITERION=DUCTILE, CRITERION=SHEAR, and, in
Abaqus/Explicit, with CRITERION=JOHNSON COOK.
Set this parameter equal to the value of the power coefficient,
.
- DEFINITION
-
This parameter can be used only in conjunction with CRITERION=MSFLD.
Set DEFINITION=MSFLD (default) to specify the MSFLD damage initiation criterion by providing the limit equivalent
plastic strain as a tabular function of .
Set DEFINITION=FLD to specify the MSFLD damage initiation criterion by providing the limit major
strain as a tabular function of minor strain.
- DEPENDENCIES
-
Set this parameter equal to the number of field variables included in the
definition of the damage initiation properties. If this parameter is omitted,
it is assumed that the damage initiation properties are constant or depend only
on temperature. This parameter cannot be used with CRITERION=JOHNSON COOK.
- FAILURE MECHANISMS
-
This parameter can be used only in conjunction with CRITERION=USER.
Set this parameter equal to the total number of failure mechanisms to be
specified in a user-defined damage initiation criterion. This parameter value
must be a nonzero.
- FEQ
-
This parameter can be used only in conjunction with CRITERION=MK.
Set this parameter equal to the critical value of the deformation severity
index for equivalent plastic strains, .
The default value is .
Set this parameter equal to zero if the deformation severity factor for
equivalent plastic strains should not be considered for the evaluation of the
Marciniak-Kuczynski criterion.
- FNN
-
This parameter can be used only in conjunction with CRITERION=MK.
Set this parameter equal to the critical value of the deformation severity
index for strains normal to the groove direction, .
The default value is .
Set this parameter equal to zero if the deformation severity factor for
strains normal to the groove should not be considered for the evaluation of the
Marciniak-Kuczynski criterion.
- FNT
-
This parameter can be used only in conjunction with CRITERION=MK.
Set this parameter equal to the critical value of the deformation severity
index for shear strains, .
The default value is .
Set this parameter equal to zero if the deformation severity factor for
shear strains should not be considered for the evaluation of the
Marciniak-Kuczynski criterion.
- FREQUENCY
-
This parameter can be used only in conjunction with CRITERION=MK.
Set this parameter equal to the frequency, in increments, at which the
Marciniak-Kuczynski analysis is going to be performed. By default, the
M-K analysis is performed every increment;
that is, FREQUENCY=1.
- GROWTH TOLERANCE
-
This parameter can be used only in conjunction with CRITERION=MAXPE, CRITERION=MAXPS, CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, CRITERION=QUADS, or CRITERION=USER for enriched elements in
Abaqus/Standard.
Include this parameter to define a separate tolerance used for crack growth.
Set this parameter equal to the tolerance within which the damage initiation
criterion in enriched elements with an existing crack must be satisfied. If
this parameter is included but no value is specified, the value is set by the TOLERANCE parameter.
- KS
-
This parameter can be used only in conjunction with CRITERION=SHEAR.
Set this parameter equal to the value of .
The default value is .
- LODE DEPENDENT
-
Include this parameter to define a ductile damage initiation criterion that
depends on the Lode angle.
- NORMAL DIRECTION
-
This parameter can be used only in conjunction with CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, or CRITERION=QUADS for enriched elements in
Abaqus/Standard.
Set NORMAL DIRECTION=1 (default) to specify that a new crack orthogonal to the
element local 1-direction will be introduced when the damage initiation
criterion is satisfied.
Set NORMAL DIRECTION=2 to specify that a new crack orthogonal to the element local
2-direction will be introduced when the damage initiation criterion is
satisfied.
- NUMBER IMPERFECTIONS
-
This parameter can be used only in conjunction with CRITERION=MK.
Set this parameter equal to the number of imperfections to be considered for
the evaluation of the Marciniak-Kuczynski analysis. These imperfections are
assumed to be equally spaced in the angular direction. By default, four
imperfections are used.
- OMEGA
-
This parameter can be used only in conjunction with CRITERION=MSFLD in
Abaqus/Explicit.
Set this parameter equal to the factor
used for filtering the ratio of principal strain rates used for the evaluation
of the MSFLD damage initiation criterion. The
default value is .
- PEINC
-
This parameter can be used only in conjunction with CRITERION=MSFLD in
Abaqus/Explicit.
Set this parameter equal to the accumulated increment in equivalent plastic
strain used to trigger the evaluation of the
MSFLD damage initiation criterion. The default
value is
(
%).
- POSITION
-
This parameter can be used only in conjunction with CRITERION=MAXPE, CRITERION=MAXPS, CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, CRITERION=QUADS, or CRITERION=USER for enriched elements in
Abaqus/Standard.
Set POSITION=CENTROID (default) to use the stress/strain at the element centroid
ahead of the crack tip to determine if the damage initiation criterion is
satisfied and to determine the crack propagation direction (if needed).
Set POSITION=COMBINED to use the stress/strain extrapolated to the crack tip to
determine if the damage initiation criterion is satisfied and to use the
stress/strain at the element centroid to determine the crack propagation
direction (if needed).
Set POSITION=CRACKTIP to use the stress/strain extrapolated to the crack tip to
determine if the damage initiation criterion is satisfied and to determine the
crack propagation direction (if needed).
Set POSITION=NONLOCAL to use the stress/strain extrapolated to the crack tip to
determine if the damage initiation criterion is satisfied and to use the
stress/strain averaged over a group of elements around the crack tip in the
enriched region to determine the crack propagation direction (if needed). This
option can be used only in conjunction with CRITERION=MAXPE or CRITERION=MAXPS.
- PROPERTIES
-
This parameter can be used only in conjunction with CRITERION=USER.
Set this parameter equal to the number of material constants being specified
for a user-defined damage initiation criterion. The parameter value must be a
nonzero value.
- RATE DEPENDENT
-
This parameter can be used only in conjunction with CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, or CRITERION=QUADS for cohesive elements with traction separation behavior in
Abaqus/Explicit.
Include this parameter to define the damage initiation criterion as a
function of the effective rate of separation.
- R CRACK DIRECTION
-
This parameter can be used only in conjunction with POSITION=NONLOCAL.
Set this parameter equal to the radius around the crack tip within which the
elements are included for calculating the averaged stress/strain used to obtain
the crack propagation direction. The default value is three times the typical
element characteristic length in the enriched region.
- SMOOTHING
-
This parameter can be used only in conjunction with POSITION=NONLOCAL.
Set SMOOTHING=NONE (default) to use the stress/strain at the integration points
directly for averaging.
Set SMOOTHING=NODAL to assemble the stress/strain to element nodes and then
interpolate to the integration points for averaging.
- TOLERANCE
-
This parameter can be used only in conjunction with CRITERION=MAXPE, CRITERION=MAXPS, CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, CRITERION=QUADS, or CRITERION=USER for enriched elements in
Abaqus/Standard.
Set this parameter equal to the tolerance within which the damage initiation
criterion must be satisfied. The default is 0.05.
- UNSTABLE GROWTH TOLERANCE
-
This parameter can be used only in conjunction with CRITERION=MAXPE, CRITERION=MAXPS, CRITERION=MAXE, CRITERION=MAXS, CRITERION=QUADE, CRITERION=QUADS, or CRITERION=USER for enriched elements in
Abaqus/Standard.
Include this parameter to define a separate tolerance used for unstable
crack growth.
Set this parameter equal to the tolerance within which the damage initiation
criterion in enriched elements with an existing crack must be satisfied for
multiple elements to be allowed to crack without excessively cutting back the
increment size in an unstable crack growth analysis. If this parameter is
included but no value is specified, the default value is infinity.
- WEIGHTING METHOD
-
This parameter can be used only in conjunction with POSITION=NONLOCAL.
Set WEIGHTING METHOD=UNIFORM (default) to average the stress/strain with a uniform weight
function.
Set WEIGHTING METHOD=GAUSS to average the stress/strain with a Gaussian weight function.
Set WEIGHTING METHOD=CUBIC SPLINE to average the stress/strain with a cubic spline weight
function.
Set WEIGHTING METHOD=USER to average the stress/strain with a user-defined weight
function.
Data lines
to specify damage initiation for CRITERION=DUCTILE without the LODE DEPENDENT parameter
- First line
-
Equivalent plastic strain at damage initiation.
-
Stress triaxiality, ().
-
Strain rate.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the equivalent plastic strain at damage
initiation as a function of triaxiality, strain rate, temperature, and other
predefined field
variables.
Data lines
to specify damage initiation for CRITERION=DUCTILE, LODE DEPENDENT- First
line
-
Equivalent plastic strain at damage initiation.
-
Stress triaxiality, .
-
Lode angle term, .
-
Strain rate.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Third field variable.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)
-
Fourth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the equivalent plastic strain at damage
initiation as a function of triaxiality, Lode angle, strain rate, temperature,
and other predefined field
variables.
Data lines
to specify damage initiation for CRITERION=FLD- First
line
-
Major principal strain at damage initiation.
-
Minor principal strain.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to five field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)
-
Sixth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the major principal strain at damage initiation
as a function of minor principal strain, temperature, and other predefined
field
variables.
Data lines
to specify damage initiation for CRITERION=FLSD- First
line
-
Major principal stress at damage initiation.
-
Minor principal stress.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to five field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)
-
Sixth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the major principal stress at damage initiation
as a function of minor principal stress, temperature, and other predefined
field
variables.
Data lines
to specify damage initiation for CRITERION=HASHIN- First
line
-
Longitudinal tensile strength of the lamina.
-
Longitudinal compressive strength of the lamina.
-
Transverse tensile strength of the lamina.
-
Transverse compressive strength of the lamina.
-
Longitudinal shear strength of the lamina.
-
Transverse shear strength of the lamina.
-
Temperature, if temperature dependent.
-
First field variable.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than one)
-
Second field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the dependence of the strengths on temperature
and other predefined field
variables.
Data lines
to specify damage initiation for CRITERION=HYSTERESIS ENERGY- First
line
-
Material constant .
(Units of )
-
Material constant .
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to five field variables per line.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)
-
Sixth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the dependence of material constants on
temperature and other predefined field
variables.
Data lines
to specify damage initiation for CRITERION=JOHNSON COOK- First (and
only) line
-
Johnson-Cook failure parameter, .
-
Johnson-Cook failure parameter, .
-
Johnson-Cook failure parameter, .
-
Johnson-Cook failure parameter, .
-
Johnson-Cook failure parameter, .
-
Melting temperature, .
-
Transition temperature, .
-
Reference strain rate, .
Data lines
to specify damage initiation for CRITERION=MK- First
line
-
Groove size relative to nominal thickness of the section,
.
-
Angle (in degrees) with respect to the 1-direction of the local material
orientation.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to five field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)
-
Sixth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the groove size as a function of angular
distance, temperature, and other predefined field
variables.
Data lines
to specify damage initiation for CRITERION=MSFLD, DEFINITION=MSFLD- First
line
-
Equivalent plastic strain at initiation of localized necking.
-
Ratio of minor to major principal strains, .
-
Equivalent plastic strain rate.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the equivalent plastic strain at damage
initiation as a function of ,
equivalent plastic strain rate, temperature, and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=MSFLD, DEFINITION=FLD- First
line
-
Major principal strain at initiation of localized necking.
-
Minor principal strain.
-
Equivalent plastic strain rate.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the major principal strain at damage initiation
as a function of minor principal strain, equivalent plastic strain rate,
temperature, and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=QUADE or CRITERION=MAXE without the RATE DEPENDENT parameter
- First line
-
Nominal strain at damage initiation in a normal-only mode.
-
Nominal strain at damage initiation in a shear-only mode that involves
separation only along the first shear direction.
-
Nominal strain at damage initiation in a shear-only mode that involves
separation only along the second shear direction.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum normal and shear tractions at
damage initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=QUADE, RATE DEPENDENT or CRITERION=MAXE, RATE DEPENDENT- First
line
-
Nominal strain at damage initiation in a normal-only mode.
-
Nominal strain at damage initiation in a shear-only mode that involves
separation only along the first shear direction.
-
Nominal strain at damage initiation in a shear-only mode that involves
separation only along the second shear direction.
-
Effective rate of separation.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum normal and shear tractions at
damage initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=QUADS or CRITERION=MAXS without the RATE DEPENDENT parameter
- First line
-
Maximum nominal stress in the normal-only mode.
-
Maximum nominal stress in the first shear direction (for a mode that
involves separation only in this direction).
-
Maximum nominal stress in the second shear direction (for a mode that
involves separation only in this direction).
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum normal and shear tractions at
damage initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=QUADS, RATE DEPENDENT or CRITERION=MAXS, RATE DEPENDENT- First
line
-
Maximum nominal stress in the normal-only mode.
-
Maximum nominal stress in the first shear direction (for a mode that
involves separation only in this direction).
-
Maximum nominal stress in the second shear direction (for a mode that
involves separation only in this direction).
-
Effective rate of separation.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum normal and shear tractions at
damage initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=MAXPE- First
line
-
Maximum principal strain at damage initiation.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to six field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than six)
-
Seventh field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum principal strain at damage
initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=MAXPS- First
line
-
Maximum principal stress at damage initiation.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to six field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than six)
-
Seventh field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the maximum principal stress at damage
initiation as a function of temperature and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=SHEAR- First
line
-
Equivalent plastic strain at damage initiation.
-
Shear stress ratio, .
-
Strain rate.
-
Temperature, if temperature dependent.
-
First field variable.
-
Second field variable.
-
Etc., up to four field variables.
- Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)
-
Fifth field variable.
-
Etc., up to eight field variables per line.
Repeat this set of data lines
as often as necessary to define the equivalent plastic strain at damage
initiation as a function of the shear stress ratio, strain rate, temperature,
and other predefined field
variables.
Data
lines to specify damage initiation for CRITERION=USER- First
line
-
Give the material constants, eight per line.
Repeat this data line as often
as necessary to define all material constants.
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