In-situ multi-scale deformation behaviors of Portevin-Le Chatelier bands in Al-Mg-Sc-Zr alloys

This study investigates the multi-scale deformation behaviors of Portevin–Le Chatelier (PLC) bands in an Al-Mg-Sc-Zr alloy using in-situ scanning electron microscopy (SEM) tensile testing combined with multi-scale digital image correlation (DIC). At the grain scale, PLC bands are observed to manifest as either non-crystallographic deformation bands or crystallographic slip traces. This distinction is governed by the grain orientation. Multi-scale analysis shows that Al3(Sc, Zr) precipitates of varying sizes exert distinct influences on the PLC effect. Additionally, although both X-shaped and linear PLC conjugate bands correspond to specific fracture modes, their relationship is not consistently predictable.