ADD POINTS BY EXTRAPOLATING SWIFT EXTRAPOLATION

Extends an effective true stress–strain curve beyond the measured necking strain using a combined Swift–Voce hardening law. Supply the fitted Swift (K, n, ε₀) and Voce (A, B, C) parameters along with the desired extrapolation strain range to append analytically computed points to the input curve. Use this worker to prepare full flow-stress curves for material card authoring in LS-DYNA or similar solvers.

When to use

Classification: process.

Tagged: extrapolation, flow_stress, hardening, mat_24, material_curve, necking, stress_strain, swift.

Inputs

Label ID Type Default Required Description
Curve To Be Extrapolated curvetobeextrapolated vector   Input effective true stress–strain curve measured up to the onset of necking (X = plastic strain [-], Y = true stress [MPa]); the extrapolated points will be appended to this curve.
Strain Start strain_start scalar 0.0   Plastic strain value [-] at which the Swift–Voce extrapolation begins; typically set to the last measured strain point or the necking strain (default 0.0).
Strain End strain_end scalar 0.0   Plastic strain value [-] at which the extrapolation terminates; must be greater than strain_start and defines the upper bound of the appended curve segment (default 0.0).
Swift K swift_k scalar 0.0   Swift hardening coefficient K [MPa] in the Swift law σ = K(ε₀ + ε)ⁿ; obtain from a prior Swift parameter-fit worker (default 0.0).
Swift N swift_n scalar 0.0   Swift hardening exponent n [-] in the Swift law σ = K(ε₀ + ε)ⁿ; obtain from a prior Swift parameter-fit worker (default 0.0).
Voce A voce_a scalar 0.0   Voce saturation stress parameter A [MPa] in the Voce law σ = A − B·exp(−C·ε); obtain from a prior Voce parameter-fit worker (default 0.0).
Voce B voce_b scalar 0.0   Voce stress-range parameter B [MPa] in the Voce law σ = A − B·exp(−C·ε); obtain from a prior Voce parameter-fit worker (default 0.0).
Voce C voce_c scalar 0.0   Voce saturation-rate parameter C [-] in the Voce law σ = A − B·exp(−C·ε); controls how quickly the stress saturates toward A (default 0.0).
Swift Percentage swift_percentage scalar 0.5    
Voce Percentage voce_percentage scalar 0.5    
Num Dig Points num_dig_points scalar 100    

Outputs

Label ID Type Description
curve_swift_voce_extrapolate_output_1 curve_swift_voce_extrapolate_output_1 vector Extended effective true stress–strain curve (X = plastic strain [-], Y = true stress [MPa]) consisting of the original measured points with the Swift–Voce extrapolated segment appended, ready for material card import.

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_voce_extrapolate


Auto-generated from transformation schema. Worker id: curve_swift_voce_extrapolate. Schema hash: d5f743725b6a. Hand-curated docs in workerexamples/ override this page when present.