Defining tensile failure

The tensile failure model uses the hydrostatic pressure stress as a failure measure to model dynamic spall (the crumbling of a material) or a pressure cutoff. For more information, see Tensile Failure Model.

  1. Create a material model as described in one of the following sections:

  2. From the Suboptions menu in the Edit Material dialog box, select Tensile Failure.

    A Suboption Editor appears.

  3. Click the arrows to the right of the Number of field variables field to increase or decrease the number of field variables on which the hydrostatic cutoff stress depends.
  4. Select Use temperature-dependent data to define the data that depend on temperature.

    A column labeled Temp appears in the Data table.

  5. Specify the failure choice for the failed material points.

    • Select Allow element deletion when the failure criterion is met to allow element removal.
    • Specify behavior for the pressure stress and deviatoric stresses.
      1. From the Pressure list, select the behavior for the pressure stress.
        • Select BRITTLE to require the pressure stress to be compressive when the failure criterion is met.
        • Select DUCTILE to limit the pressure stress by the hydrostatic cutoff stress when the failure criterion is met.
      2. From the Shear list, select the behavior for the deviatoric stresses.
        • Select BRITTLE to set the deviatoric stress to zero when the failure criterion is met.
        • Select DUCTILE to specify that the deviatoric stresses are unaffected when the failure criterion is met.

  6. Enter the following data in the Data table:

    Hydrostatic cutoff stress

    Value of the hydrostatic cutoff stress, σ cutoff (positive in tension).

    Temp

    Temperature.

    Field n

    Predefined field variables.

    For detailed information on how to enter data, see Entering tabular data.

  7. Click OK to return to the Edit Material dialog box.