Títol:
|
Strain hardening behavior of ARMCO iron processed by ECAP
|
Autor/a:
|
Cabrera Marrero, José M.; Muñoz Bolaños, Jairo Alberto; Higuera Cobos, Oscar Fabián
|
Altres autors:
|
Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica; Universitat Politècnica de Catalunya. PROCOMAME - Processos de Conformació de Materials Metàl·lics |
Abstract:
|
The strain hardening behavior of an ARMCO iron processed by ECAP at room temperature up to sixteen passes following route Bc was investigated through Hollomon and differential Crussard-Jaoul models. Results indicate that the Hollomon analysis shows some deviations from the experimentally determined true stress – true strain curves while the differential Crussard-Jaoul analysis based on the Ludwik equation and the modified Crussard- Jaoul analysis based on the Swift equation fit better when two work hardening exponents are considered. As expected, the strength of the material increased with the number of ECAP passes. Indeed the ultimate tensile stress reached a maximum of ~900MPa after 16 passes, which is more than three times higher than the UTS of the annealed material. Nevertheless, the strain hardening capacity of the material was reduced in comparison with the material without severe plastic deformation. For that reason the tensile ductility was also reduced at increasing ECAP passes. The increase in strength was attributed to the reduction of the grain size through refined sub-grains with high density of dislocations. After sixteenth passes the original grain size (namely 70 mm) was reduced down to 300 to 400 nm observing a good correspondence with the Hall-Petch relationship. The microstructural analysis, carried out by EBSD, showed an increasing amount in the fraction of high Angle Grain Boundaries (HAGB) after 1 pass due to the regeneration of the microstructure with a smaller grain size |
Matèries:
|
-Àrees temàtiques de la UPC::Enginyeria dels materials -Armco International Corporation -Iron -Acer -- Propietats mecàniques |
Drets:
|
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/ |
Tipus de document:
|
Article - Versió publicada Article |
Publicat per:
|
Institute of Physics (IOP)
|
Compartir:
|
|