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• Strain localizations (SLs) were observed preferentially in Copper-type grains in the CR Cu-Fe-P specimens. • Self-annealing at room temperature was observed at the deformed GBs and at SLs in the CR specimens. • TEM and TKD confirms that DSRX and CSRX were responsible for the self-annealing phenomena in the CR specimens. • CPFEM simulation was showing the nearby predictions for average grain size (GS avg) and texture fraction. • Activation of single-slip system in the Copper and S oriented grains was the primary cause of SLs formations. Deformation of Cu-Fe-P alloys at cryogenic temperature (CT) leads to the evolution of a complex microstructure, which includes deformed and recrystallized grains, strain localizations (SLs), and heterogeneous deformation. In this study, specimens of Cu-Fe-P alloy were subjected to cryogenic rolling (CR) at reduction ratios (RR) of 20, 40, 60, and 80%. The microstructural evolution of the CR specimens was characterized using electron back-scattered diffraction (EBSD) and high-resolution transmission electron microscopy (HR-TEM). Severely deformed CR specimens showed SLs, which formed predominantly in the Copper and S oriented grains. After deformation, the CR specimens exhibited self-annealing behavior, which is also referred to as static recrystallization (SRX). Self-annealing at room temperature (RT) caused grain nucleation at the deformed grain boundaries (GBs) and at the SLs. The nucleation of new grains was attributed to both discontinuous SRX (DSRX) and continuous SRX (CSRX) phenomena. The characteristics of DSRX and CSRX grains were analyzed based on transmission Kikuchi diffraction (TKD) and HR-TEM investigations. DSRX grains were surrounded by high-angle GBs, whereas CSRX grains showed sub-boundaries with no dislocations inside. The as-received Cu-Fe-P specimen showed a weak plane-strain texture that intensity increased with an increase in the RR. The CR-80 specimen showed the highest-intensity for plane-strain texture components. SRX at the SLs showed preferential formations of Copper, Brass and S-nucleated grains in the CR-80 specimen. In this study, crystal plasticity finite element method (CPFEM) was used to calculate the stored energy, relative slip activity and texture fractions for the CR specimens. Copper and S oriented grains showed the occurrence of predominant single-slip systems near the severely deformed regions which was the primary cause of SLs formation. [Display omitted] [ABSTRACT FROM AUTHOR]

• Microstructural and crystallographic texture evolution in the RTR and CR ETP copper were investigated systematically. • CR-processed specimens showed higher hardening and softening rate than RTR-processed specimens. • SRX at room temperature was the main softening phenomena observed in the severely deformed specimens. • DSRX and CSRX were responsible for the nucleation of small grains at room temperature in the severely deformed RTR and CR-processed specimens. • Time-dependent decay in the hardness values for the RTR and CR specimens, attributed to the SRV and SRX. The present study addresses the evolution of microstructural and crystallographic texture in room-temperature-rolled (RTR) and cryogenic-rolled (CR) electrolytic tough-pitch (ETP) copper. Copper specimens were subjected to 20, 40, 60, and 80% reductions via RTR and CR processing. The microstructure evolution of the severely deformed RTR and CR specimens revealed deformed and recrystallized grains. Static recrystallization (SRX) at room temperature (RT) was observed in the severely deformed RTR and CR specimens. Both discontinuous SRX (DSRX) and continuous SRX (CSRX) were responsible for the nucleation of small grains at RT. Particle-stimulated nucleation (PSN) was also responsible for small-grain formations around the Cu 2 O particles. The initial ETP copper specimen showed a weak texture whose intensity increased after the RTR and CR deformation. The texture intensity of the severely deformed specimens was affected by both deformation and the SRX phenomena. The CR specimens showed texture that was stronger than that of the RTR specimens up to the point of an intermediate reduction (60%), whereas at higher deformation (80%), the RTR specimens showed stronger texture intensity compared with that of the CR specimens. The texture weakening in the CR80 specimen was due to the formation of strain localizations (SLs) and to the nucleation at SLs. Large amounts of stored energy and SL formation in severely deformed CR specimens led to a different recrystallization texture compared with that of RTR specimens. A Cube component was dominant in the RTR80, whereas Goss, Copper and S components were observed in the CR80 specimen for SRX grains. The CR specimen showed a relatively high hardness value compared with the RTR specimen. Time-dependent decay in the hardness values for both the RTR and the CR specimens were attributed to room-temperature recovery (SRV) and recrystallization (SRX). [ABSTRACT FROM AUTHOR]