.. _auto_dynakeyword_mat083:

*CREATE A MAT_083 FOR LS-DYNA*
==============================

Generates an LS-DYNA MAT_083 (*MAT_FU_CHANG_FOAM) keyword block for rate-dependent foam materials. Accepts density, elastic modulus, and strain-rate–dependent stress–strain curves, then outputs a ready-to-include keyword text. Use this worker when authoring foam material cards for crash or structural decks that require strain-rate sensitivity.

When to use
-----------

Classification: **data**.

Tagged: ``MAT_FU_CHANG_FOAM``, ``deck-authoring``, ``foam``, ``keyword``, ``ls-dyna``, ``mat_083``, ``material-card``, ``strain-rate``.

Inputs
------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20 20 20

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Material Name
     - material_name
     - scalar
     - —
     - 
     - Alphanumeric label written into the MAT_083 card header (e.g. 'FOAM_PU_45kg'); leave blank to omit the name field.
   * - Material ID
     - material_i_d
     - scalar
     - —
     - 
     - Integer material ID referenced by *PART cards in the deck (e.g. 83); must be unique within the model.
   * - Table Id
     - table_id
     - scalar
     - —
     - 
     - LS-DYNA table ID (integer) that groups the strain-rate curves via *DEFINE_TABLE; provide when using a pre-existing table instead of individual curve IDs.
   * - Curve Id
     - curve_id
     - scalar
     - —
     - 
     - LS-DYNA load-curve ID (integer) for the single quasi-static stress–strain curve; used when no multi-rate table is supplied.
   * - Density
     - density
     - scalar
     - —
     - 
     - Mass density of the foam (units consistent with the deck, e.g. tonne/mm³ for standard LS-DYNA models); required for a valid material card.
   * - Elastic Modulus
     - elastic_modulus
     - scalar
     - —
     - 
     - Young's modulus / initial elastic stiffness of the foam (units consistent with the deck, e.g. MPa); drives the unloading slope in MAT_083.
   * - Hardening Curve
     - strain-rate_curves
     - vector
     - —
     - 
     - Comma-separated list of stress-vs-strain curve vectors, one per strain rate, ordered to match the values in the 'Strain rates' input; each curve must cover the full expected strain range.
   * - Strain Rates
     - strainrates
     - scalar
     - —
     - 
     - Comma-separated list of strain-rate values (e.g. '0.001,0.1,1.0,10.0') corresponding positionally to the curves supplied in 'Strain-rate Curves'; units must match the deck time base.
   * - TC
     - t_c
     - scalar
     - —
     - 
     - 
   * - KCON
     - kco_n
     - scalar
     - —
     - 
     - 
   * - DAMP
     - dam_p
     - scalar
     - —
     - 
     - 
   * - BVFLAG
     - bvfla_g
     - scalar
     - —
     - 
     - 
   * - SFLAG
     - sfla_g
     - scalar
     - —
     - 
     - 
   * - RFLAG
     - rfla_g
     - scalar
     - —
     - 
     - 
   * - TFLAG
     - tfla_g
     - scalar
     - —
     - 
     - 
   * - SRAF
     - sra_f
     - scalar
     - —
     - 
     - 
   * - REF
     - re_f
     - scalar
     - —
     - 
     - 
   * - HU
     - h_u
     - scalar
     - —
     - 
     - 
   * - Shape
     - shape
     - scalar
     - —
     - 
     - 
   * - Number Of Dig Points
     - numberof_dig_points
     - scalar
     - 200
     - 
     - LCINT

Outputs
-------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - dynakeyword_mat083_output_1
     - dynakeyword_mat083_output_1
     - text
     - Plain-text LS-DYNA keyword block (*MAT_FU_CHANG_FOAM / MAT_083) ready to be appended to or included in an LS-DYNA input deck.

Disciplines
-----------

- cae.preprocessing.deck_authoring
- engineering.crash.dynamics
- engineering.material.library

.. raw:: html

   <hr style="margin-top:2em">
   <p style="font-size:11px;color:#888">
   Auto-generated from <code>transformation</code> schema. Worker id: <code>dynakeyword_mat083</code>. Schema hash: <code>b283b5583752</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>