Abstract
Within exliuded Mg_<89>Zn_4Y_7(at%) alloysontaining a long period stacking ordered(LPSO) phase,a unique defomation mode refemation mode referred to as "kink deformation"is found to occur within the LPSO phase grains, frming kink bands that are each represented by an array of geometnically necessary dislocation. Intragranular misonentation axis(IGMA) analysis suggests that this kink dformation results in lattic rotation predominately about the <1100>,<0110>,<0001>,and<1210>axes of the 18R-type LPSO structure. IGMA analysis is based on slip-induced lattioe rotation and determination of its rotation axis(Taylor axis). Therefore,it is possible to determine the dominant slop mod in a grain that is defoemed, by matching the Tayloeaxis for agiven slip system to its experimentally obtained IGMA destnbution. In this study,the study, the strong preferenoe of<1100>and<0110>Taylor axes suggests that kinking occurs through a basal <a> slip mode. The<0001> Taylor axes suggest that kink bands form through a prismatic<a>slip mod. These axes are categorized as "principal rotation" axes, which result from one Burgers vector of dislocations. Kink bands with a <1210> Taylor axis are produced through combination of dislocation. It is concluded that IGMA analysis can be effectively used to study and geometrically classify kink bands.
