Identification and validation of an extended Stewart-Cazacu micromechanics damage model applied to Ti 6Al 4V specimens exhibiting positive stress triaxialities
Date
Authors
Rojas-Ulloa, Carlos
Valenzuela, Marian
Tuninetti, Víctor
Habraken, A.M.
Valenzuela, Marian
Tuninetti, Víctor
Habraken, A.M.
Authors
Date
Datos de publicación:
10.1177/14644207211009933
Keywords
Cazacu Yield Criterion - Coupled Damage Law - Ductile Fracture - Finite Element Modeling - Hcp Material - Micromechanics Damage Model - Coalescence - Crystallization - Nucleation - Scanning Electron Microscopy - Tensile Testing - Titanium Alloys - Coalescence Modeling - Damage Characterization - Displacement Curve - Essential Features - Experimental Campaign - Material Parameter Identification - Numerical Predictions - Prediction Capability - Damage Detection
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Abstract
In this research, the Stewart-Cazacu micromechanics coupled damage model is extended and validated adding nucleation and coalescence models as new damage mechanisms. The Ti 6Al 4V titanium alloy is chosen as a suitable hcp ductile material to be modeled using this extended damage law. The characterization of the damage evolution in this alloy is addressed throughout a quasi-static experimental campaign. Damage characterization relies on in situ X-ray tomography data and scanning electron microscopy imaging technique. The validation procedure consists in the implementation into the finite element research software Lagamine of ULiège and in the comparison of numerical predictions and experimental results. Load displacement curves and damage-related state variables at fracture configuration from smooth and notched bar specimens submitted to tensile tests are analyzed. The nucleation and coalescence model extensions as well as an accurate elastoplastic and damage material parameter identification for Ti 6Al 4V samples are essential features to reach a validated model. The prediction capabilities exhibited for large strains are in good agreement with experimental results, while the near-fracture strains can still be improved. © 2021 Elsevier B.V., All rights reserved.
Description
Keywords
Cazacu Yield Criterion , Coupled Damage Law , Ductile Fracture , Finite Element Modeling , Hcp Material , Micromechanics Damage Model , Coalescence , Crystallization , Nucleation , Scanning Electron Microscopy , Tensile Testing , Titanium Alloys , Coalescence Modeling , Damage Characterization , Displacement Curve , Essential Features , Experimental Campaign , Material Parameter Identification , Numerical Predictions , Prediction Capability , Damage Detection
Citation
10.1177/14644207211009933