.. _auto_dynakeyword_mat124:

*CREATE A MAT_124 WITH OR WITHOUT STRAIN-RATES FOR LS-DYNA*
===========================================================

Generates an LS-DYNA MAT_124 (Tension-Compression Plasticity) keyword block, optionally including Cowper-Symonds strain-rate parameters. Use this worker to author rate-dependent or rate-independent piecewise-linear plasticity material cards ready for inclusion in an LS-DYNA input deck.

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

Classification: **data**.

Tagged: ``Cowper_Symonds``, ``LS-DYNA``, ``MAT_124``, ``deck_authoring``, ``mat124``, ``material_keyword``, ``strain_rate``, ``tension_compression_plasticity``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Material Name
     - material_name
     - scalar
     - MAT 124
     - ✓
     - Alphanumeric label written into the MAT_124 keyword header (e.g. 'Steel_DP600'); default 'MAT 124' is acceptable for generic cards.
   * - Material ID
     - material_i_d
     - scalar
     - 1
     - ✓
     - Integer material ID referenced by part/section cards in the LS-DYNA deck; default 1, must be unique within the deck.
   * - Density
     - density
     - scalar
     - 7.89e-09
     - ✓
     - Mass density in consistent units (default 7.89e-9 tonne/mm³ for steel in mm-N-s); adjust for other unit systems or materials.
   * - Elastic Modulus
     - elastic_modulus
     - scalar
     - 210.0
     - ✓
     - Young's modulus in consistent units (default 210.0 GPa / kN/mm²); governs the elastic response before yield.
   * - Poissons Ratio
     - poissons_ratio
     - scalar
     - 0.3
     - ✓
     - Poisson's ratio (dimensionless, default 0.3); defines lateral-to-axial strain coupling in the elastic regime.
   * - C
     - c
     - scalar
     - 0.0
     - 
     - Cowper-Symonds strain-rate coefficient C (units 1/s, default 0.0); set to a non-zero value to activate rate-dependent hardening scaling.
   * - P
     - p
     - scalar
     - 0.0
     - 
     - Cowper-Symonds strain-rate exponent p (dimensionless, default 0.0); used together with C to scale yield stress at elevated strain rates.
   * - FAIL
     - fail
     - scalar
     - 0.0
     - 
     - Effective plastic strain at element erosion/failure (dimensionless, default 0.0 = no erosion); set a positive value to enable element deletion at the specified strain threshold.
   * - LCIDT
     - lc_ten
     - vector
     - —
     - ✓
     - Tensile Hardening Curve
   * - LCIDC
     - lc_comp
     - vector
     - —
     - 
     - Compression Hardening Curve
   * - LCIDTSR
     - lc_ten_sr
     - vector
     - —
     - 
     - Yield SF vs Strain-rate in Tension
   * - LCIDCSR
     - lc_comp_sr
     - vector
     - —
     - 
     - Yield SF vs Strain-rate in Compression
   * - SRFLG
     - srfl_g
     - string
     - 0.0
     - 
     - Strain-rate  Flag
   * - LCFAIL
     - lcfail
     - vector
     - —
     - 
     - Failure Plastic-strain vs Strain-rate
   * - Strain Rates
     - strain_rates
     - textarea
     - 0.0
     - 
     - Keyvalue for Strain rate data   <a class='btn btn-xs btn-default' target='_blank' href='https://www.d3view.com/docs/master/workflows/Glossary.html#keyvalueinput'> <i class='fa fa-external-link'> </i> View more </a>
   * - PC
     - pc
     - scalar
     - 0.0
     - 
     - Compressive mean-Pressure  at which the yield stress follows the LCIDC
   * - PT
     - pt
     - scalar
     - 0.0
     - 
     - Tensile mean-Pressure  at which the yield stress follows the LCIDT
   * - PCUTC
     - pcutc
     - scalar
     - 0.0
     - 
     - Pressure cut-off stress in Compression
   * - PCUTT
     - pcutt
     - scalar
     - 0.0
     - 
     - Pressure cut-off stress in Tension
   * - PCUTF
     - pcutf
     - scalar
     - 0.0
     - 
     - Pressure cut-off activation flag
   * - SRFILT
     - srfil_t
     - scalar
     - 0
     - 
     - Strain-rate Filtering
   * - K
     - k
     - scalar
     - 0
     - 
     - K
   * - Number Of Dig Points
     - numberof_dig_points
     - scalar
     - 100
     - 
     - LCINT
   * - Cuve ID
     - curve_id
     - scalar
     - 1
     - 
     - 
   * - Use Log for Strain Rates
     - use_log
     - string
     - no
     - 
     - Strain-rate  Flag

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - MAT_124
     - mat124
     - textarea
     - Formatted LS-DYNA *MAT_124 keyword text block, ready to be copied into or appended to an input deck (.k / .key file).

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

- cae.preprocessing.deck_authoring
- engineering.material.calibration
- 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_mat124</code>. Schema hash: <code>8b3150ca4304</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>