Direct influence of recovery behaviour on mechanical properties in oxygen-free copper processed using different SPD techniques: HPT and ECAP

• Main Authors: Meshal Y. Alawadhi, Shima Sabbaghianrad, Yi Huang, Terence. G. Langdon
• Format: Article
• Language: English
• Published: Elsevier 2017-10-01
• Series: Journal of Materials Research and Technology
• Online Access: http://www.sciencedirect.com/science/article/pii/S2238785417301606
• ISSN: 2238-7854

Oxygen-free copper of 99.95 wt.% purity was severely deformed at room temperature by two modes of severe plastic deformation, equal-channel angular pressing (ECAP) and high-pressure torsion (HPT). ECAP was performed using 4, 16 and 24 passes, and HPT was performed using 1/2, 1 and 10 turns. The results show that while recovery occurs during both ECAP and HPT processing, copper shows a faster recovery rate with HPT processing than ECAP. The occurrence of recovery was observed at an equivalent strain exceeding â¼12 that led to an enhancement in the uniform plastic deformation. The influence of recovery behaviour on the mechanical properties was investigated using X-ray diffraction, microhardness and tensile testing. Keywords: Ductility, Equal-channel angular pressing, High-pressure torsion, Recovery, Strain rate sensitivity, Work hardening