Propagating Portevin–LeChatelier deformation bands in Cu-15 at.% Al polycrystals: experiments and theoretical description

By simultaneous high resolution recordings of stress and local strain along the specimen length, using a novel multizone laser scanning extensometer, the nucleation and propagation of Portevin–LeChatelier (PLC) deformation bands has been studied on Cu-l5 at.% Al polycrystals. The extensometer data provides an accurate classification of the types A, B and C of PLC bands as well as propagation rates, band strain and band width. These are compared with results of a new theoretical space-time analysis of propagating PLC bands which combines an explicit physical description of dynamic strain ageing kinetics with plastic deformation kinetics.