.. _auto_curve_swift_extrapolate:

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

Extends a stress-strain curve beyond the necking point using Swift power-law extrapolation. Provide the effective true stress–strain curve up to necking, the elastic modulus, Swift hardening exponent, and the desired strain range to generate a smoothly extrapolated full curve suitable for MAT_24 or similar material card input.

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

Classification: **process**.

Tagged: ``curve-extrapolation``, ``extrapolation``, ``hardening``, ``mat_24``, ``necking``, ``power-law``, ``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
     - —
     - 
     - Effective true stress vs. true plastic strain curve measured up to the onset of necking (X = strain, Y = stress); leave unconnected only if you intend to supply all parameters without a seed curve.
   * - Emod
     - emod
     - scalar
     - 210
     - 
     - Young's modulus (GPa or consistent unit matching the stress axis of the input curve); default 210 GPa is appropriate for steel — change for aluminium, titanium, etc.
   * - N
     - n
     - scalar
     - 0
     - 
     - Swift hardening exponent n controlling the slope of the power-law extrapolation (σ = C·εⁿ); default 0 disables extrapolation slope — set to the fitted n value from tensile test data.
   * - X Begin
     - x_begin
     - scalar
     - 0
     - 
     - Strain value at which the extrapolated region starts (typically the last measured strain point); default 0 — should be set to the necking-onset strain of the input curve.
   * - X End
     - x_end
     - scalar
     - 1
     - 
     - Strain value at which extrapolation terminates (i.e., maximum true plastic strain in the output); default 1.0 — adjust to the fracture strain or simulation requirement.
   * - Number Of Points
     - numberof_points
     - scalar
     - 100
     - 
     - Total number of evenly spaced data points in the output extrapolated curve; default 100 — increase for smoother curves in high-strain-rate or fine-mesh simulations.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curve_swift_extrapolate_output_1
     - curve_swift_extrapolate_output_1
     - vector
     - Full true stress vs. true plastic strain curve with Swift-extrapolated points appended beyond the necking strain, ready for use as a material hardening curve in LS-DYNA MAT_24 or equivalent.

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_extrapolate <https://www.d3view.com/api/workflow/example?id=curve_swift_extrapolate>`_

.. raw:: html

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_swift_extrapolate</code>. Schema hash: <code>884fa6cebf1c</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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