.. _auto_dynakeyword_mat100df:

*CREATE A MAT_100 DF KEYWORD FOR LS-DYNA*
=========================================

Generates an LS-DYNA *MAT_100_DA (spotweld failure) keyword block from user-supplied material parameters such as elastic modulus, yield stress, and failure strain. Use this worker to author or inject a MAT_100 DF card into a simulation deck without manually formatting the keyword file.

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

Classification: **data**.

Tagged: ``deck_authoring``, ``dyna_keyword``, ``keyword``, ``ls-dyna``, ``mat_100``, ``mat_100_df``, ``material``, ``spotweld``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Material Name
     - material_name
     - scalar
     - —
     - 
     - User-defined label string for the material card (e.g. 'Steel_Spotweld'); optional — leave blank to omit the name field in the keyword.
   * - Material ID
     - material_i_d
     - scalar
     - —
     - 
     - Integer material ID (MID) that uniquely identifies this *MAT card within the LS-DYNA deck; optional — required when embedding the keyword into an existing model.
   * - RHO
     - rh_o
     - scalar
     - —
     - 
     - Mass density (RHO) of the material in consistent model units (e.g. kg/mm³ or t/mm³); optional — must be provided for a valid LS-DYNA keyword.
   * - EMOD
     - emo_d
     - scalar
     - —
     - 
     - Young's (elastic) modulus (EMOD) in pressure units consistent with the model (e.g. MPa or GPa); optional — governs elastic stiffness of the spotweld.
   * - PR
     - p_r
     - scalar
     - —
     - 
     - Poisson's ratio (PR), dimensionless, typically 0.28–0.33 for metals; optional — controls lateral strain coupling in the elastic regime.
   * - SIGY
     - sig_y
     - scalar
     - —
     - 
     - Initial yield stress (SIGY) in pressure units matching EMOD; optional — defines the onset of plastic deformation in the spotweld.
   * - ETAN
     - eta_n
     - scalar
     - —
     - 
     - Tangent (plastic hardening) modulus (ETAN) in pressure units; optional — set to 0 for elastic-perfectly-plastic behaviour.
   * - EFAIL
     - efai_l
     - scalar
     - —
     - 
     - Effective plastic strain at element failure (EFAIL); optional — element is deleted when this strain is reached; leave null to disable strain-based failure.
   * - NRR
     - nr_r
     - scalar
     - —
     - 
     - Normalisation / exponent parameter NRR used in the MAT_100 failure surface definition; optional — consult the LS-DYNA theory manual for applicable range.
   * - NRS
     - nr_s
     - scalar
     - —
     - 
     - 
   * - NRT
     - nr_t
     - scalar
     - —
     - 
     - 
   * - MRR
     - mr_r
     - scalar
     - —
     - 
     - 
   * - MSS
     - ms_s
     - scalar
     - —
     - 
     - 
   * - MTT
     - mt_t
     - scalar
     - —
     - 
     - 
   * - NF
     - n_f
     - scalar
     - —
     - 
     - 
   * - RS
     - r_s
     - scalar
     - —
     - 
     - 
   * - OPT
     - op_t
     - scalar
     - —
     - 
     - 
   * - F VAL
     - f_va_l
     - scalar
     - —
     - 
     - 
   * - TRUE T
     - tru_e_t
     - scalar
     - —
     - 
     - 
   * - DMGOPT
     - dmgop_t
     - scalar
     - —
     - 
     - 

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - dynakeyword_mat100df_output_1
     - dynakeyword_mat100df_output_1
     - text
     - Formatted LS-DYNA *MAT_100_DA keyword text block (plain text / string) ready to be written to or appended into a .k / .key deck file.

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

- cae.preprocessing.deck_authoring
- 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_mat100df</code>. Schema hash: <code>98f577f1e8ae</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>