*VISCOUS

Specify viscous material properties for the two-layer viscoplastic model.

This option is used to define the viscous properties for the two-layer viscoplastic material model. It must be used in conjunction with the ELASTIC and PLASTIC options.

This page discusses:

Optional parameters

DEPENDENCIES

Set this parameter equal to the number of field variable dependencies included in the definition of the material properties, in addition to temperature. If this parameter is omitted, it is assumed that the material properties depend only on temperature. See Material Data Definition for more information.

LAW

Set LAW=STRAIN (default) to choose a strain hardening law. This parameter setting is superseded by LAW=POWER LAW.

Set LAW=TIME to choose a time hardening law. This parameter setting is superseded by LAW=TIME POWER LAW.

Set LAW=USER to input the creep law using user subroutine CREEP.

Set LAW=ANAND to choose an Anand law.

Set LAW=DARVEAUX to choose a Darveaux law.

Set LAW=DOUBLE POWER to choose a double power law.

Set LAW=POWER LAW to choose a power law. It is recommended that you use this parameter setting rather than LAW=STRAIN.

Set LAW=TIME POWER LAW to choose a time power law. It is recommended that you use this parameter setting rather than LAW=TIME.

TIME

This parameter is relevant only when LAW=TIME or LAW=TIME POWER LAW.

Set TIME=CREEP to use creep time.

Set TIME=TOTAL (default) to use total time.

Data lines for LAW=TIME or LAW=STRAIN

First line
  1. A. (Units of F-nL2nT-1-m.)

  2. n.

  3. m.

  4. f.

  5. Temperature.

  6. First field variable.

  7. Second field variable.

  8. Third field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than three)
  1. Fourth 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 viscous constants on temperature and other predefined field variable.

Data lines for LAW=USER

First line
  1. f.

  2. Temperature.

  3. First field variable.

  4. Second field variable.

  5. Etc. up to seven field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than seven)
  1. Eighth 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 viscous constants on temperature and other predefined field variables.

Data lines for LAW=ANAND

First line
  1. S1. (Units of FL−2.)

  2. Q/R. (Units of θ.)

  3. A. (Units of T−1.)

  4. ξ.

  5. m.

  6. A0. (Units of FL−2.)

  7. s^. (Units of FL−2.)

  8. n.

Second line
  1. a.

  2. S2. (Units of FL−2θ-1.)

  3. S3. (Units of FL−2θ-2.)

  4. A1. (Units of FL−2θ-1.)

  5. A2. (Units of FL−2θ-2.)

  6. A3. (Units of FL−2T.)

  7. A4. (Units of FL−2T2.)

  8. f.

Data lines for LAW=DARVEAUX

First line
  1. Css. (Units of T−1.)

  2. Q/R. (Units of θ.)

  3. α. (Units of F−1L2.)

  4. n.

  5. ϵT.

  6. B.

  7. f.

Data lines for LAW=DOUBLE POWER

First line
  1. A1. (Units of T−1.)

  2. B1. (Units of θ.)

  3. C1.

  4. A2. (Units of T−1.)

  5. B2. (Units of θ.)

  6. C2.

  7. σ0. (Units of FL−2.)

  8. f.

Data lines for LAW=POWER LAW

First line
  1. q0. Units of FL−2.)

  2. n.

  3. m.

  4. Blank space.

  5. ε˙0. The default is 1.0. (Units of T−1.)

  6. f.

  7. Temperature.

  8. First field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than one)
  1. Second 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 viscous constants on temperature and other predefined field variables.

Data lines for LAW=TIME POWER LAW

First line
  1. q0. (Units of FL−2.)

  2. n.

  3. m.

  4. ε˙0. The default is 1.0. (Units of T−1.)

  5. f.

  6. Temperature.

  7. First field variable.

  8. Second field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than two)
  1. Third 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 viscous constants on temperature and other predefined field variables.