Kinetics of Lüders Bands in Al–Mg Alloy with Structural Heterogeneity

The paper deals with Lüders deformation in an aluminum-magnesium alloy with structural heterogeneity in the form of a friction stir weld. It is found that a complex structural state due to the weld seam causes two zones in the specimen: the base metal where Lüders deformation occurs and the stir zone where deformation does not localize. Thermomechanically affected zones with increased microhardness compared to the base metal and stir zone are sources of Lüders deformation fronts. Depending on the strain rate, deformation fronts can move intermittently or continuously. The kinetics of fronts is determined by the response of active deformable media to external mechanical action and can be described within the autowave concept of plastic deformation similarly to homogeneous materials.