Defining a porous metal plasticity model

The porous metal plasticity model describes materials that exhibit damage in the form of void initiation and growth. You can also use this model for some powder metal process simulations at high relative densities (relative density is defined as the ratio of the volume of solid material to the total volume of the material). The model is based on Gurson's porous metal plasticity theory with void nucleation and is intended for use with materials that have a relative density that is greater than 0.9. The model is adequate for relatively monotonic loading.

Context:

See Porous metal plasticity, for more information.

  1. From the menu bar in the Edit Material dialog box, select MechanicalPlasticityPorous Metal Plasticity.

    (For information on displaying the Edit Material dialog box, see Creating or editing a material.)

  2. Enter a value for the initial Relative density of the material.

  3. Toggle on Use temperature-dependent data to define data that depend on temperature.

    A column labeled Temp appears in the Data table.

  4. 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 data depend.

  5. Enter the following data in the Data table:

    q1, q2, and q3

    Material parameters q1, q2, q3.

    For typical metals the ranges of the parameters reported in the literature are q1 = 1.0 to 1.5, q2 = 1.0, and q3 = q12 = 1.0 to 2.25 (see Necking of a round tensile bar). The original Gurson model is recovered when q1 = q2 = q3 = 1.0.

    Temp

    Temperature.

    Field n

    Predefined field variables.

    You may need to expand the dialog box to see all the columns in the Data table. For detailed information on how to enter data, see Entering tabular data.

  6. If desired, select Porous Failure Criteria from the Suboption menu to specify material failure criteria for an Abaqus/Explicit analysis. See Defining porous material failure criteria” for details.

  7. If desired, select Void Nucleation from the Suboption menu to define the nucleation of voids in the porous material. See Defining void nucleation in a porous material” for details.

  8. Click OK to create the material and to close the Edit Material dialog box. Alternatively, you can select another material behavior to define from the menus in the Edit Material dialog box (see Browsing and modifying material behaviors, for more information).