Local Plastic Deformation of Kink Band Opposing External Stress in Mg-Zn-Y Alloy

In order to determine a factor of kink strengthening, spatial distribution of crystal rotation, kink interface rotation and plastic strain in deformed kink bands was investigated. Fine mesh was drawn on kink microstructure using focused-ion beam to map the plastic strain caused by the further deformation. Results clearly showed the existence of local deformation in the opposite direction of the external stress. This opposing plastic deformation was explained well the observed crystal rotation and rotation of the kink interface, provided that the rank-1 connection was maintained during deformation. The constraint between connected kink bands was suggested to be the origin of this opposite deformation and one of the factors leading to kink strengthening.