*CYCLIC HARDENING

Specify the size of the elastic range for the combined hardening model.

This option is used to define the evolution of the size of the elastic range for the nonlinear combined isotropic/kinematic hardening model. It can be used only in conjunction with the PLASTIC option. The size of the elastic range remains constant during the analysis if this option is not used.

This page discusses:

See Also
*PLASTIC
In Other Guides
Models for Metals Subjected to Cyclic Loading
UHARD
VUHARD

ProductsAbaqus/StandardAbaqus/Explicit

TypeModel data

LevelModel

Optional parameters

DEPENDENCIES

Set this parameter equal to the number of field variable dependencies included in the definition of the cyclic hardening behavior, in addition to temperature. If this parameter is omitted, this behavior does not depend on field variables. See Material Data Definition for more information.

PARAMETERS

Include this parameter to provide the material parameters Q∞ and b directly.

USER

Include this parameter to define the size of the elastic range in user subroutine UHARD in Abaqus/Standard analyses and user subroutine VUHARD in Abaqus/Explicit analyses. This parameter cannot be included if the kinematic hardening component is specified via half-cycle test data using DATA TYPE=HALF CYCLE on the associated PLASTIC option.

Optional parameter for use with the USER parameter

PROPERTIES

Set this parameter equal to the number of property values needed as data in user subroutine UHARD in Abaqus/Standard analyses and user subroutine VUHARD in Abaqus/Explicit analyses. The default is PROPERTIES=0.

Optional parameters if neither PARAMETERS nor USER is included

EXTRAPOLATION

This parameter specifies the extrapolation method for the yield stress with respect to the equivalent plastic strain.

If you use the CYCLIC HARDENING option multiple times to specify test data at different equivalent plastic strain rates, you can use the EXTRAPOLATION parameter only one time, when you specify data at a zero equivalent plastic strain rate (CYCLIC HARDENING, RATE=0.0). On the subsequent options, you must either omit the EXTRAPOLATION parameter or specify the same method as that used at a zero equivalent plastic strain rate.

Set EXTRAPOLATION=CONSTANT (default) to use a constant value of the yield stress outside the specified range of the equivalent plastic strains.

Set EXTRAPOLATION=LINEAR to use linear extrapolation (based on the slope) of the yield stress outside the specified range of the equivalent plastic strains.

RATE

Set this parameter equal to the equivalent plastic strain rate, ε¯˙p⁢l, for which this stress-strain curve applies.

Data lines to give tabular material data

First line

  1. Equivalent stress defining the size of the elastic range.

  2. Equivalent plastic strain.

  3. Temperature.

  4. First field variable.

  5. Etc., up to five field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than five)

  1. Sixth field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the values of the isotropic component as a function of plastic strain, temperature, and other predefined variables.

Data lines to define the material parameters directly (PARAMETERS)

First line

  1. Equivalent stress defining the size of the elastic range at zero plastic strain.

  2. Isotropic hardening parameter, Q∞.

  3. Isotropic hardening parameter, b.

  4. Temperature.

  5. First field variable.

  6. Etc., up to four field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four)

  1. Fifth field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the dependence of the material parameters on temperature and other predefined field variables.

Data lines for USER with PROPERTIES

First line

  1. Give the hardening properties, eight per line.

Repeat this data line as often as necessary to define all hardening properties.