The Portevin-Le Chatelier effect: a review of experimental findings

The Portevin-Le Chatelier (PLC) effect manifests itself as an unstable plastic flow during tensile tests of some dilute alloys under certain regimes of strain rate and temperature. The plastic strain becomes localized in the form of bands which move along a specimen gauge in various ways as the PLC effect occurs. Because the localization of strain causes degradation of the inherent structural properties and surface quality of materials, understanding the effect is crucial for the effective use of alloys. The characteristic behaviors of localized strain bands and techniques commonly used to study the PLC effect are summarized in this review. A brief overview of experimental findings, the effect of material properties and test parameters on the PLC effect, and some discussion on the mechanisms of the effect are included. Tests for predicting the early failure of structural materials due to embrittlement induced by the PLC effect are also discussed.