Fig. 1. Schematic illustration of used ECAP die(a) and image showing specimens before and after ECAP process(b)
Fig. 2. Shape and dimensions of tensile specimen
Fig. 3. Inverse pole figure(IPF) maps at center region of samples with pass number of 0(a), 1(b), 2(c), 4(d), 8(e), and 12(f)
Fig. 4. Misorientation angle distributions of initial and ECAPed samples(a), and variation in average misorientation angle with applied number of pass(b)
Fig. 5. Variations in average grain size at top, center, and bottom regions and its standard deviation (SD) with number of pass
Fig. 6. IPF maps at top(a), center(b), and bottom(c) regions of 12 pass-ECAPed sample
Fig. 7. Distribution of rockwell hardness from top to bottom(a) and from left to right(b) of initial and ECAPed samples
Fig. 8. Variation in average hardness and standard deviation of hardness with number of pass
Fig. 9. True stress–strain curves of initial and ECAPed samples
Fig. 10. Variations in average GOS and recrystallization fraction(a) and grain size, tensile strength, and hardness at center region (b) with number of pass
Fig. 11. Image showing loading direction of axial and circumferential tensile specimens(a), and true stress-strain curves along axial and circumferential directions of samples with pass number of 0(b), 1(c), 2(d), 4(e), and 8(f)
Fig. 12. Comparisons of tensile strength(a) and yield strength(b) along axial and circumferential directions
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