Periodic crystal lattice rotation in microband groups in a bcc metal

摘要

Fe-3mass percent Si specimens with a columnar grain structure were deformed in compression at ambient temperature. Groups of microbands were found in the vicinity of a grain boundary. These microband groups are characterized by shear and a periodic change of crystal lattice orientation within distances of 1-2 mu m. Furthermore, new grains with a size of 200-300 nm were formed in the microband groups during deformation up to 36 percent strain. A local lattice rotation model is given that explains the experimental observations.