Understanding the texture evolution and deformation mechanism of Zr-2.5Nb alloy during cold rolling

Zirconium (Zr) alloy is widely used in the nuclear industry due to its low thermal neutron absorption cross-section and excellent mechanical properties. The texture easily formed in the hcp -structured α-Zr determines its service performance. To analyze the texture evolution and deformation mechanism during cold rolling, the Zr-2.5Nb alloy was rolled to various reductions in two directions (rolling direction (RD) and transverse direction (TD)) at two deformation temperatures (room temperature (RT) and cryogenic temperature (CT)). A combined approach of experimental observation and crystal plasticity simulation was employed to systematically investigate the texture evolution and deformation mechanism under cold rolling. The TD-spread elliptical texture is formed in α-Zr during RD-rolling, while the disc-shaped basal texture is produced during TD-rolling. The prismatic slip has no effect on the texture type. The basal slip leads to the formation of strong basal texture. The pyramidal slip causes the basal poles to tilt toward RD. Both prismatic and basal slips lead to the formation of the TD-spread elliptical texture with double peaks. At RT, the final F ND of RD-rolling is similar to that of TD-rolling, a similarity that is caused by basal slip. The Kearns factors of normal direction (ND) is recorded as F ND . At CT, {10 2} and {11 1} twinning play an important role in the early stage of deformation. Compared to TD-rolling at RT, the relatively inactive basal slip results in lower texture intensity during TD-rolling at CT. This study deepens our understanding of the texture evolution and deformation mechanisms of Zr alloy.