Modified Crushable Foam

LS-DYNA now offers a modified version of *MAT_CRUSHABLE_FOAM in the form of *MAT_MODIFIED_CRUSHABLE_FOAM . In the new material model, the strain rate effects can be included in the foam a *DEFINE_TABLE . To reduce or eliminate the noise in the evaulation of the new yield stress as a function of strain and strain-rate, LS-DYNA offers a modified strain-rate calculation and also a max variation of strain at every cyle. This is depicted in the following image.

When using this model, the effective plastic strain is replaced with the volumetric strain variable in D3PLOT for easy fringe plotting.

(Click for a larger view)
Strain Rates in Crushable Foam

  • Sandeep says:

    Hi Pls tell me how do i model MAT57 for foam shell mesh

  • Elham says:


    When using crushable foam material, how does ls dyna calculate the E, module of Elasticity? is this the maximum slope of stress strain curve? is there a way that it accepts a lower value for E?


    • Suri Bala says:

      HI Elham,

      E is takes as the max of what we provide in the material card and the maximum slope of the stress-strain curve.


  • Elham says:

    Hi Suri,

    Thank you very much for your reply. Is this E only used for tension calculation, or it is used for compression as well? I assume in compression it should follow the input curve from the beginning, right?

    Thank you,

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