Kink-band strengthening was first quantitatively evaluated using an Mg–Zn–Y single crystal containing
long-period stacking ordered (LPSO) nanoplates. The ability of a kink-band boundary to act
as a barrier that hinders the motion of dislocations is high and comparable to that of a general random
grain boundary. Nevertheless, a kink-band boundary is regarded as a simple tilt boundary in
the dislocation model. One reason for the anomalous ability of kink-band boundary acting as barriers
is related to its peculiar hierarchical structure, in which many small kink bands with high crystal
rotation angles accumulate in a localized region.