In situ atomic-scale observation of a novel lattice reorienting process in pure Ti

A lattice reorienting process is observed in Ti at atomic resolution through in situ transmission electron microscope tensile test. A new orientational relationship is identified between matrix (M) and reoriented (R) lattice: [1¯21¯3] _R //[1¯21¯0] _M and (01¯11) _R //(0002) _M , which is distinct from the known twinning and “twinning-like” relationships in hexagonal close-packed metals. Molecular dynamics simulation results suggest that the reorienting process is accompanied by the evolution of grain boundary misfit dislocations to lattice dislocations, as well as by the transformation of (0002) basal to (01¯11) pyramidal plane. Atomic rearrangement analysis shows that the short-distance shuffling of atoms can accomplish the transformation.