Journal of Materials Research and Technology Journal of Materials Research and Technology
J Mater Res Technol 2017;6:369-77 DOI: 10.1016/j.jmrt.2017.05.005
Original Article
Direct influence of recovery behaviour on mechanical properties in oxygen-free copper processed using different SPD techniques: HPT and ECAP
Meshal Y. Alawadhia,, , Shima Sabbaghianradb, Yi Huanga,, , Terence. G. Langdona
a Materials Research Group, Faculty of Engineering and the Environment, University of Southampton, Southampton, United Kingdom
b Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, United States of America
Received 11 April 2017, Accepted 15 May 2017
Abstract

Oxygen-free copper of 99.95wt.% 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 ∼12 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
J Mater Res Technol 2017;6:369-77 DOI: 10.1016/j.jmrt.2017.05.005