Open-source Python framework developed within the FABER network (COST Action CA23109 - WG 4.7 LCF) for advanced fatigue data processing, constitutive parameter identification, and standardized test protocol export in low-cycle fatigue domain.
Post-processes continuous raw time-series data exported from universal testing machines (LabControl, Instron, MTS):
- Automated cycle segmentation and hysteresis loop extraction.
- Feature extraction at stabilized half-life (
$N_f / 2$ ):$\sigma_a$ ,$\varepsilon_{ap}$ , directional dynamic moduli ($E_{\text{upp}}, E_{\text{btm}}$ ), and plastic work ($W_p$ ). - Failure identification using physical criteria (
$N_f^{25}$ load drop and$N_f^{E10}$ stiffness drop). - Automated generation of 2-page single-specimen PDF protocols (
Protocol_LCF.pyandProtocol_Ratcheting.py).
Ingests the consolidated 9-row Inputs.txt record to perform constitutive parameter identification:
-
Compatible 3D Method: Singular Value Decomposition (SVD) in
$\log_{10}(\varepsilon_{ap}) - \log_{10}(\sigma_a) - \log_{10}(2N_f)$ space enforcing$n' = b/c$ and$K' = \sigma_f' / (\varepsilon_f')^{n'}$ . - Conventional Method: Independent Basquin, Manson–Coffin, and Ramberg–Osgood regressions.
- Evaluates properties across both constant (
$E_{\text{const}}$ ) and dynamic ($E_{\text{var}}$ ) elastic moduli. - Non-linear 4-parametric energy modeling for
$\text{SWT}$ and$W_p$ ($FP = C_1 N_f^{C_2} + C_3 N_f^{C_4}$ ). - Generates a publication-ready, 2-page PDF test protocol (
Protocol.py) with clickable DOI citations.
- User Manual: Read the User Manual (PDF)
- Sample Output 1 - LCF: View a Pre-Generated LCF Test Protocol (PDF)
- Sample Output 2 - Ratcheting: View a Pre-Generated Ratcheting Test Protocol (PDF)
- Sample Output 3 - 3D method: View a Pre-Generated 3D method Protocol (PDF)
git clone https://github.com/radimhalama/LCF-test-protocols.git
cd LCF-test-protocols
pip install -r requirements.txt