[line-stress-strain] Engineering Stress-Strain Curve

[MarkusNeusinger]

Description

A stress-strain curve shows the relationship between applied stress and resulting strain in a material under loading. It reveals elastic region, yield point, strain hardening, ultimate tensile strength, and fracture point — characterizing material mechanical behavior.

Applications

• Comparing mechanical properties of different materials or alloys
• Determining yield strength for structural design
• Quality control testing in manufacturing
• Teaching material science and mechanics of materials

Data

• strain (numeric) — engineering strain (dimensionless, typically 0 to 0.5)
• stress_mpa (numeric) — engineering stress in MPa
• Size: 100-500 data points

Notes

• Label key regions: elastic, plastic, necking
• Mark yield point (0.2% offset method), UTS, and fracture point
• Show elastic modulus (Young's modulus) as slope annotation in elastic region
• Optional: overlay multiple materials for comparison

[claude]

✅ Spec ID: line-stress-strain

Rationale: Uses line as the plot type since this is fundamentally a line/curve visualization, with stress-strain as the variant identifying the specific engineering relationship. Distinct from sn-curve-basic (fatigue S-N curve) which plots stress vs. cycles-to-failure.

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: line-stress-strain

PR: #4439

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specification.md

line-stress-strain: Engineering Stress-Strain Curve

Description

An engineering stress-strain curve visualizes the relationship between applied stress (MPa) and resulting strain (dimensionless) in a material under uniaxial tensile loading. The curve reveals distinct mechanical behavior regions — elastic deformation, yielding, strain hardening, and necking — culminating in fracture. It is the foundational plot for characterizing material mechanical properties and comparing material performance.

Applications

• Comparing mechanical properties (yield strength, UTS, ductility) of different materials or alloys for design selection
• Determining yield strength using the 0.2% offset method for structural engineering design calculations
• Quality control testing in manufacturing to verify materials meet specified mechanical property requirements
• Teaching material science and mechanics of materials concepts in engineering education

Data

• strain (numeric) — engineering strain (dimensionless), typically ranging from 0 to 0.5
• stress_mpa (numeric) — engineering stress in megapascals (MPa)
• Size: 100-500 data points sampled from a tensile test
• Example: Tensile test data for mild steel showing elastic region, yield plateau, strain hardening, and necking to fracture

Notes

• Label key regions on the curve: elastic, plastic (strain hardening), and necking
• Mark critical points: yield point (0.2% offset method), ultimate tensile strength (UTS), and fracture point
• Annotate the elastic modulus (Young's modulus) as the slope in the elastic region, with a visible slope line or text annotation
• Draw the 0.2% offset line (parallel to the elastic region, offset by 0.002 strain) to illustrate yield point determination
• Optional: overlay curves for multiple materials to enable direct comparison of mechanical behavior

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: line-stress-strain
PR: #4439 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

Or use workflow dispatch for bulk operations.

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🤖 spec-create workflow