.. _auto_lsdyna_spotweld_material_generator:

*CONVERTS LS-DYNA MATERIAL TO SPOTWELD MATERIAL DATA*
=====================================================

Reads an LS-DYNA input deck and spotweld test-data files to generate calibrated spotweld material parameters for use in LS-DYNA models. It filters base materials by Young's modulus, cross-references a bill-of-materials weld-pair table, and outputs failure envelopes, test datasets, and a ready-to-use LS-DYNA spotweld material keyword block.

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

Tagged: ``btgsd``, ``failure_envelope``, ``keyword``, ``lsdyna``, ``material_generation``, ``spotweld``, ``stdf``, ``weld``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - LS-DYNA Input File
     - lsdyna_file
     - file
     - —
     - ✓
     - LS-DYNA input deck (.k / .key) from which base material definitions are extracted; materials whose Young's modulus does not match the specified value are ignored.
   * - STDF
     - spotweld_file
     - file
     - —
     - ✓
     - Excel STDF (Spotweld Test Data File) containing physical spotweld coupon test results; each sheet must be named using the convention MAT1_THICKNESS1_MAT2_THICKNESS2_TESTTYPE (e.g., DP600_1.5_DP600_1.5_TENSION).
   * - Youngs Modulus
     - youngs_modulus
     - text
     - 210
     - ✓
     - Reference Young's modulus in GPa (default 210 for steel); any material in the LS-DYNA deck whose modulus does not match this value is excluded from spotweld material generation.
   * - BTGSD
     - bill_of_materials_file
     - file
     - —
     - ✓
     - Excel BTGSD (Bill-of-Materials / weld-pair definition) file specifying which material–thickness pairs are joined at each spotweld location, used to match test data to the correct weld configuration.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - Materials
     - materials
     - dataset
     - Tabular dataset of filtered base materials extracted from the LS-DYNA deck, retaining only entries whose Young's modulus matches the specified reference value.
   * - Spotweld test data
     - spotweld_data
     - dataset
     - Parsed and normalised spotweld coupon test data ingested from the STDF Excel file, organised by material–thickness–test-type combination.
   * - Spotweld failures
     - spotweld_failures
     - dataset
     - Computed spotweld failure envelope dataset (force/moment limits per weld configuration) derived from the test data and used to define the material failure surface.
   * - Spotweld LS-DYNA keyword material
     - spotweld_material
     - text
     - Ready-to-include LS-DYNA keyword text block (e.g., *MAT_SPOTWELD / *CONSTRAINED_SPOTWELD) containing the calibrated spotweld material parameters for direct insertion into a simulation deck.
   * - Bill-of-Materials
     - bom_data
     - dataset
     - Parsed bill-of-materials dataset showing weld-pair assignments (material, thickness, joint type) as read from the BTGSD Excel file.
   * - Logs
     - logs
     - dataset
     - Processing log dataset recording warnings, skipped materials, sheet-name parsing errors, and any mismatches between the BOM and available test data.

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

- cae.preprocessing.deck_authoring
- engineering.crash.dynamics
- engineering.material.calibration
- engineering.material.failure

.. raw:: html

   <hr style="margin-top:2em">
   <p style="font-size:11px;color:#888">
   Auto-generated from <code>platform</code> schema. Worker id: <code>lsdyna_spotweld_material_generator</code>. Schema hash: <code>5cc81ad988cc</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>