.. _auto_curves_engstress_variance:

*CREATE A CURVE USING THE STANDARD VARIANCE OF YIELD, ULTIMATE AND FAILURE STRESS*
==================================================================================

Generates engineering stress–strain variance curves by scaling a quasi-static base curve so that its yield, ultimate, and failure stress points span user-supplied min/max bounds. Use this worker when you need to produce a family of bounding stress–strain curves (e.g., for material scatter or design-of-experiments studies) from a set of dynamic and quasi-static coupon test curves.

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

Classification: **process**.

Tagged: ``bounding-curves``, ``coupon``, ``dynamic``, ``engstress``, ``failure``, ``material-scatter``, ``min-max``, ``quasi-static``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Dynamic Eng Stress Strain Curves
     - dynamic_eng_stress_strain_curves
     - vector
     - —
     - 
     - Collection of dynamic engineering stress–strain curves (multiple vectors allowed) used as reference population for variance scaling; optional if only quasi-static data is available.
   * - Quasi-Static Eng Stress Strain Curve
     - quasi-static_eng_stress_strain_curve
     - vector
     - —
     - 
     - Single quasi-static engineering stress–strain curve that serves as the base curve whose key stress points are rescaled to the supplied min/max bounds.
   * - QS Yield Stress Min
     - qs_yield_stress_min
     - scalar
     - 0
     - 
     - Minimum allowable quasi-static yield stress value (stress units consistent with the input curves, default 0); defines the lower bound of the yield stress scatter band.
   * - QS Yield Stress Max
     - qs_yield_stress_max
     - scalar
     - 0
     - 
     - Maximum allowable quasi-static yield stress value (stress units consistent with the input curves, default 0); defines the upper bound of the yield stress scatter band.
   * - QS Ultimate Stress Min
     - qs_ultimate_stress_min
     - scalar
     - 0
     - 
     - Minimum allowable quasi-static ultimate (peak) stress value (same stress units, default 0); sets the lower bound of the ultimate stress scatter band.
   * - QS Ultimate Stress Max
     - qs_ultimate_stress_max
     - scalar
     - 0
     - 
     - Maximum allowable quasi-static ultimate (peak) stress value (same stress units, default 0); sets the upper bound of the ultimate stress scatter band.
   * - QS Elongation Strain Min
     - qs_elongation_strain_min
     - scalar
     - 0
     - 
     - Minimum allowable quasi-static elongation (failure) strain value (dimensionless or %, default 0); sets the lower bound of the failure strain scatter band.
   * - QS Elongation Strain Max
     - qs_elongation_strain_max
     - scalar
     - 0
     - 
     - Maximum allowable quasi-static elongation (failure) strain value (dimensionless or %, default 0); sets the upper bound of the failure strain scatter band.
   * - Elastic Modulus
     - elastic_modulus
     - scalar
     - 0
     - 
     - 
   * - Yield Offset
     - yield_offset
     - scalar
     - 0.002
     - 
     - 
   * - Levels to generate
     - levelstogenerate
     - scalar
     - 3
     - 
     - 
   * - Level Names
     - level_names
     - scalar
     - min,mean,max
     - 
     - 

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curves_engstress_variance_output_1
     - curves_engstress_variance_output_1
     - vector
     - Generated engineering stress–strain variance curve (or family of curves) whose yield, ultimate, and failure stress points are bounded by the supplied min/max limits, ready for downstream material card authoring or DOE studies.

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

- data.curve.pair
- 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=curves_engstress_variance <https://www.d3view.com/api/workflow/example?id=curves_engstress_variance>`_

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curves_engstress_variance</code>. Schema hash: <code>21ea64bc91cd</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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