This option is used to provide material properties that define the initiation of damage.
Products: ABAQUS/Standard ABAQUS/Explicit
Type: Model data
Level: Model
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=MAXE to specify a damage initiation criterion based on the maximum separation criterion for cohesive elements.
Set CRITERION=MAXS to specify a damage initiation criterion based on the maximum traction criterion for cohesive elements.
Set CRITERION=MK to specify a damage initiation criterion based on a Marciniak-Kuczynski analysis.
Set CRITERION=QUADE to specify a damage initiation based on the quadratic separation-interaction criterion for cohesive elements.
Set CRITERION=QUADS to specify a damage initiation based on the quadratic traction-interaction criterion for cohesive elements.
Set CRITERION=SHEAR to specify a damage initiation criterion based on the shear failure strain.
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. See “Specifying field variable dependence” in “Material data definition,” Section 9.1.2 of the ABAQUS Analysis User's Manual, for more information.
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.
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.
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.
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=0.
This parameter can be used only in conjunction with CRITERION=SHEAR.
Set this parameter equal to the value of 
. The default value is 
.
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.
First line:
Equivalent fracture 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 fracture strain at damage initiation as a function of triaxiality, strain rate, temperature, and other predefined field variables.
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.
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.
First line:
Flaw 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 flaw size as a function of angular distance, temperature, and other predefined field variables.
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.
Third field variables.
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 maximum normal and shear tractions at damage initiation as a function of temperature and other predefined field variables.
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.
Third field variables.
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 maximum normal and shear tractions at damage initiation as a function of temperature and other predefined field variables.
First line:
Equivalent fracture 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 fracture strain at damage initiation as a function of the shear stress ratio, strain rate, temperature, and other predefined field variables.