.. _auto_curves_engstress_stats:

*COMPUTES KEY VALUES SUCH AS YIELD, NECKING ETC.*
=================================================

Computes key statistical properties from engineering stress-strain curves, including Yield Stress (0.2 % offset or alternative methods), Necking point, Ultimate Tensile Strength, and Fracture values. Use this worker to characterise coupon test data before material calibration or library ingestion.

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

Classification: **process**.

Tagged: ``UTS``, ``coupon``, ``engstress``, ``fracture``, ``material_characterization``, ``necking``, ``offset_method``, ``slip_correction``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Eng Stress Strain Curves
     - eng_stress_strain_curves
     - vector
     - —
     - 
     - One or more engineering stress-strain curves (stress in MPa, strain dimensionless) obtained from coupon tests; accepts multiple curves for batch processing.
   * - Slope
     - slope
     - scalar
     - 210
     - 
     - Young's Modulus in GPa used to fit the initial linear region and locate the offset line; default 210 GPa (steel) — set to 0 to let the worker auto-detect the best-fit initial slope.
   * - Yield Offset
     - yield_offset
     - scalar
     - 0.002
     - 
     - Strain offset for the 0.2 % offset yield criterion (dimensionless); default 0.002 — increase for thermoplastics or materials with a gradual elastic-to-plastic transition.
   * - True Intersection Type
     - true_intersection_type
     - list
     - xlast
     - 
     - Selects which intersection point between the true stress-strain curve and its derivative is used to identify the necking onset: 'xlast' (default, most conservative), 'xfirst', or 'xavg'.
   * - Treat Mechanical Slip
     - treat_slip
     - list
     - no
     - 
     - When set to 'yes', mechanical slip or grip-seating offset is detected and removed from the curve before computing statistics; default 'no'.
   * - Remove Failure
     - remove_failure
     - list
     - no
     - 
     - When set to 'yes', the post-fracture load-drop region is stripped from the curve before statistics are computed; default 'no'.
   * - Yield Type
     - yield_type
     - list
     - offset
     - 
     - Type of yield determiniation. By default it uses offset of the line parallel to the slope.

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curves_engstress_stats_output_1
     - curves_engstress_stats_output_1
     - dataset
     - Dataset (tabular) containing per-curve key-value statistics — Yield Stress, Yield Strain, UTS, Necking Stress/Strain, Fracture Stress/Strain, and Young's Modulus — one row per input curve.

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

- data.statistics
- engineering.material.characterization
- engineering.material.specimen

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

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

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curves_engstress_stats</code>. Schema hash: <code>0603b85a38dc</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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