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

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 b^3 from the initial values of 118.5 b^3 in the annealed state.