 |
 |
Article dans une revue
Investigation and modeling of the anomalous yield point phenomenon in pure tantalum
Abstract : 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.
https://hal-mines-paristech.archives-ouvertes.fr/hal-01070197
Contributeur : Bibliothèque Umr7633 <>
Soumis le : mardi 30 septembre 2014 - 17:17:09
Dernière modification le : mercredi 14 octobre 2020 - 03:47:44
Contributeur : Bibliothèque Umr7633 <>
Soumis le : mardi 30 septembre 2014 - 17:17:09
Dernière modification le : mercredi 14 octobre 2020 - 03:47:44