COMPUTE SWIFT EXPONENT FROM HARDENING CURVES¶
Fits the Swift power-law hardening exponent (n) to one or more effective stress–strain hardening curves by iterating over candidate n values in discrete increments and minimising the deviation against digitised reference points. Use this worker when calibrating Swift/isotropic hardening parameters for material card authoring (e.g. MAT_24).
When to use¶
Classification: process.
Tagged: curve_fitting, hardening, mat_24, material_calibration, n_exponent, power_law, swift.
Inputs¶
| Label | ID | Type | Default | Required | Description |
|---|---|---|---|---|---|
| Hardening Curves | eff_curves | vector | — | One or more effective stress–plastic-strain hardening curves (true stress vs. true strain) against which the Swift exponent will be fitted; accepts multiple curves for batch processing. | |
| Modulus | modulus | scalar | 210.0 | Young’s modulus used to separate elastic from plastic strain during fitting (GPa or consistent pressure unit); default 210.0 GPa is appropriate for steel — change for aluminium or other alloys. | |
| Swift N Inc | n_inc | scalar | 0.1 | Search increment for the Swift n exponent during the fitting iteration; default 0.1 gives a coarse scan — reduce (e.g. 0.01) for higher precision at the cost of more iterations. | |
| Number of Digitized Points to compare to Reference | ndig | scalar | 100 | Number of uniformly-spaced digitised points sampled from the reference curve for the least-squares comparison; default 100 is sufficient for most hardening curves — increase for very long or noisy curves. | |
| Number of Swift Segments after Necking | nseg | scalar | 1 | Number of Swift law segments to fit in the post-necking region; default 1 (single-segment Swift law) — increase only when a piecewise extension beyond necking is required. |
Outputs¶
| Label | ID | Type | Description |
|---|---|---|---|
| Computed Swift N Values | computed_swift_n_values | dataset | Dataset containing the best-fit Swift n exponent (and supporting fit metrics) for each input hardening curve, indexed by curve identifier. |
Disciplines¶
- data.curve.pair
- 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_get_swift_exponent_from_hardening_curves
Auto-generated from transformation schema. Worker id: curves_get_swift_exponent_from_hardening_curves. Schema hash: 59e135b37b4e. Hand-curated docs in workerexamples/ override this page when present.