Investigating the Effects of Expansion Equal Channel Angular Extrusion (Exp-ECAE) on the Dynamic Behavior of AA7075 Aluminum Alloy

• Published in: International journal of advanced design and manufacturing technology Vol. 9; no. 3
• Main Authors: Karami, J Shahbazi, Sepahi-Boroujeni, S, Khodsetan, Mohsen
• Format: Journal Article
• Language: English
• Published: Isfahan Islamic Azad University Majlesi 01.09.2016
• ISSN: 2252-0406; 2383-4447

Expansion equal channel angular extrusion (Exp-ECAE) is a severe plastic deformation (SPD) operation for processing bulk materials. In the current study, AA7075 Al was SPD-processed by expansion equal channel angular extrusion (Ex-ECAE) at various temperatures and ram velocities. Then, using split Hopkinson pressure bar (SHPB), the severely deformed products were compressed at room temperature and strain rates of 0.1~3000 s-1. Both the strain rate sensitivity (SRS) and the apparent activation volume (AAV) were determined for all deformed samples. The results revealed that the Ex-ECAE operation has noticeably increased the SRS. The tensile strength at a strain rate of 3000 s-1 was 6 times increased by conducting Ex-ECAE at 100 °C and with a ram velocity of 7 mm/min. Ex-ECAE was also capable of considerably decreasing the AAV. The results showed the yield stress of both the Exp-ECAE and the annealed samples increased with increasing the strain rate. Also, the results showed that after the Exp-ECAE process, the AAV reached to 6.3 b3 from the initial values of 118.5 b3 in the annealed state.