Unveiling the Room-Temperature Softening Phenomenon and Texture Evolution in Room-Temperature-Rolled Cu–0.13Sn Alloys

In this investigation, annealed Cu–0.13Sn alloys i.e., as-received samples were subjected to room-temperature rolling (RTR) at reduction ratios (RR) of 40 and 75 pct. Electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) was used to discuss the microstructure evolution in the as-received and RTR samples. RTR deformation resulted in the formation of Copper-type shear bands (SBs). An unusual phenomenon of static recrystallization (SRX) at room-temperature (RT)/self-annealing was observed in the severely deformed Cu–0.13Sn alloy. SBs and deformed grain boundaries (GBs) were the main sites with high levels of stored energy (SE), and new grains were nucleated in those regions via discontinuous SRX (DSRX) in the RTR samples. Continuous SRX (CSRX) was observed in grains nucleated inside the deformed grains. The fraction of SBs was increased with increases in the RR, and visco-plastic self-consistent (VPSC) modelling was used to predict the texture of the SBs in the severely deformed Cu–0.13Sn alloy. Microstructural heterogeneities had a significant effect on the evolution of the crystallographic texture in as-received and RTR samples. Under low strain (40 pct RR), a Copper-type texture was observed, whereas the severely deformed sample (75 pct RR) showed strong Copper and S components, but weak Brass component. Self-annealed grains in the SB regions and in the deformed GB regions led to the evolution of strong Copper and Rotated Cube components, but weak Brass component.