.. _auto_curve_swift_voce_extrapolate:

*ADD POINTS BY EXTRAPOLATING SWIFT EXTRAPOLATION*
=================================================

Extends an effective true stress–strain curve beyond the measured necking strain using a combined Swift–Voce hardening law. Supply the fitted Swift (K, n, ε₀) and Voce (A, B, C) parameters along with the desired extrapolation strain range to append analytically computed points to the input curve. Use this worker to prepare full flow-stress curves for material card authoring in LS-DYNA or similar solvers.

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

Classification: **process**.

Tagged: ``extrapolation``, ``flow_stress``, ``hardening``, ``mat_24``, ``material_curve``, ``necking``, ``stress_strain``, ``swift``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Curve To Be Extrapolated
     - curvetobeextrapolated
     - vector
     - —
     - 
     - Input effective true stress–strain curve measured up to the onset of necking (X = plastic strain [-], Y = true stress [MPa]); the extrapolated points will be appended to this curve.
   * - Strain Start
     - strain_start
     - scalar
     - 0.0
     - 
     - Plastic strain value [-] at which the Swift–Voce extrapolation begins; typically set to the last measured strain point or the necking strain (default 0.0).
   * - Strain End
     - strain_end
     - scalar
     - 0.0
     - 
     - Plastic strain value [-] at which the extrapolation terminates; must be greater than strain_start and defines the upper bound of the appended curve segment (default 0.0).
   * - Swift K
     - swift_k
     - scalar
     - 0.0
     - 
     - Swift hardening coefficient K [MPa] in the Swift law σ = K(ε₀ + ε)ⁿ; obtain from a prior Swift parameter-fit worker (default 0.0).
   * - Swift N
     - swift_n
     - scalar
     - 0.0
     - 
     - Swift hardening exponent n [-] in the Swift law σ = K(ε₀ + ε)ⁿ; obtain from a prior Swift parameter-fit worker (default 0.0).
   * - Voce A
     - voce_a
     - scalar
     - 0.0
     - 
     - Voce saturation stress parameter A [MPa] in the Voce law σ = A − B·exp(−C·ε); obtain from a prior Voce parameter-fit worker (default 0.0).
   * - Voce B
     - voce_b
     - scalar
     - 0.0
     - 
     - Voce stress-range parameter B [MPa] in the Voce law σ = A − B·exp(−C·ε); obtain from a prior Voce parameter-fit worker (default 0.0).
   * - Voce C
     - voce_c
     - scalar
     - 0.0
     - 
     - Voce saturation-rate parameter C [-] in the Voce law σ = A − B·exp(−C·ε); controls how quickly the stress saturates toward A (default 0.0).
   * - Swift Percentage
     - swift_percentage
     - scalar
     - 0.5
     - 
     - 
   * - Voce Percentage
     - voce_percentage
     - scalar
     - 0.5
     - 
     - 
   * - Num Dig Points
     - num_dig_points
     - scalar
     - 100
     - 
     - 

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curve_swift_voce_extrapolate_output_1
     - curve_swift_voce_extrapolate_output_1
     - vector
     - Extended effective true stress–strain curve (X = plastic strain [-], Y = true stress [MPa]) consisting of the original measured points with the Swift–Voce extrapolated segment appended, ready for material card import.

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

- data.curve.transform
- engineering.material.calibration
- engineering.material.characterization

Runnable example
----------------

A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: `/api/workflow/example?id=curve_swift_voce_extrapolate <https://www.d3view.com/api/workflow/example?id=curve_swift_voce_extrapolate>`_

.. raw:: html

   <hr style="margin-top:2em">
   <p style="font-size:11px;color:#888">
   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_swift_voce_extrapolate</code>. Schema hash: <code>d5f743725b6a</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>