Characteristics of the propagating deformation bands associated with the Portevin–Le Chatelier effect in an Al–Zn–Mg–Cu alloy

Measurements were performed on deformation bands in an Al–Zn–Mg–Cu alloy associated with the Portevin–Le Chatelier effect occurring at room temperature upon deformation in a soft tensile machine. The effects of ageing time and ageing temperature up to 200°C on the features of propagating bands were investigated. These experiments establish the important influence of precipitation on serrated flow. In particular, the band velocity Vb, the band width Lb and the band strain εb were examined. The evolution of the onset strain of bursts, εc, was also studied. Finally, experimental values were confronted to Hähnerʹs model.