Superplastic deformation behavior of 7075 aluminum alloy

Type : Publication
Auteur(s) :  TAHAR SAHRAOUI, Mohamed HADJI, Nacer BACHA, Riad BADJI, r
Année :  2003
Domaine : Métallurgie
Revue : Journal of Materials Engineering and Performance
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés :  7075 aluminum alloy, superplastic deformation, thermo mechanical treatment, warm rolling

Résumé : 

A study has been made to investigate the effect of a prior amount of warm rolling on the superplastic forming behavior of a standard grade 7075 aluminum alloy. The thermomechanical treatment process presented for grain refinement includes furnace cooling from the solution treatment temperature to the overaging temperature, warm rolling from 65–85% deformation, recrystallization, and artificial aging treatment. Increasing the amount of warm rolling beyond 80% deformation does not produce material with higher elongation to failure when the thermomechanical treatment process presented is used. The largest value of elongation to failure was 700%, which was obtained for a specimen having a grain size of 8 µm at a strain rate of 6×10−3S−1. The fracture surface exhibits a granular appearance indicative of an intergranular fracture mode. Dislocation activities within grains were observed, indicating the occurrence of dislocation slip during grain boundary sliding.