Abstract
The extremely high work hardening rate and the high cracking propensity were the main challenges that limit the successful deformation processing of rhenium. Rolling tests to 82% thickness reduction were conducted at room temperature, and three-stage twining evolution behavior was revealed. At 10% rolling reduction, primary {112¯1} tension twins were activated and dislocation accumulation appeared near the twin boundary. As the rolling reduction increases to 45%, twin-twin interactions prevailed and abundant GNDs accumulated around {112¯1} twin boundaries and {112¯1} twin- {112¯1} twin interactions. More importantly, A new twinning sequence behavior in rhenium, secondary {112¯1} twins within primary {112¯1} twins, was investigated. After twinning saturation, shear bands were formed due to the promoted local plastic deformation by the twin lamellar structure and submicron-scale isolated twins, which brought pronounced strengthening of rhenium. The extremely high work hardening rate of rhenium was found to mainly originate from the twin lamellar structure and twin-twin interactions. High temperature annealing released the stored strain energy, achieving a synergistic effect of high tensile strength and ductility. This study provides a systematic investigation into the deformation structure during the large reduction cold rolling in rhenium and provides insights into unique twinning evolution and shear bands.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have