6533b7dcfe1ef96bd12735a5
RESEARCH PRODUCT
Investigation and modeling of the anomalous yield point phenomenon in pure tantalum
Samuel ForestMatthieu MazièreSylvain FlouriotEric FinotD. ColasD. ColasD. ColasThomas Parissubject
Materials science[ SPI.MAT ] Engineering Sciences [physics]/MaterialsNucleationTantalumchemistry.chemical_elementBand propagation02 engineering and technologyTantalum01 natural sciences[SPI.MAT]Engineering Sciences [physics]/MaterialsViscosity0103 physical sciencesPhenomenological modelUltimate tensile strengthForensic engineeringGeneral Materials ScienceComposite materialTensile testing010302 applied physicsStrain (chemistry)Mechanical Engineering021001 nanoscience & nanotechnologyCondensed Matter PhysicschemistryMechanics of MaterialsStatic strain agingInfrared thermography0210 nano-technologyStrain localizationDynamic strain agingdescription
International audience; The monotonic and cyclic behavior of commercially pure tantalum has been investigated at room temperature, in order to capture and understand the occurrence of the anomalous yield point phenomenon. Interrupted tests have been performed, with strain reversals (tensile or compressive loading) after an aging period. The stress drop is attributed to the interactions between dislocations and solute atoms (oxygen) and its macroscopic occurrence is not systematically observed. InfraRed Thermography (IRT) measurements supported by Scanning Electron Microscopy (SEM) pictures of the polished gauge length of a specimen during an interrupted tensile test reveal the nucleation and propagation of a strain localization band. The KEMC (Kubin-Estrin-McCormick) phenomenological model accounting for strain aging has been identified for several loadings and strain rates at room temperature. Simulations on full specimen using the KEMC model do not show strain localization, because of the competition between viscosity and strain localization. However, a slight misalignment of the sample can promote strain localization.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2014-10-01 |