Experimental Investigations on the Temporal and Spatial Behaviors of the PLC Effect in Al--Cu Alloys
Al-Cu合金中PLC效应时域和空域行为的实验研究

The temporal and spatial behaviors of the PLC (Portevin-Le Chatlier) effect in Al-Cu alloy are systemically investigated and analyzed. Under different applied strain rates, three types of serrated stress-time curves are obtained respectively. And the similarities and differences of them are compared and interpreted qualitatively. Correspondingly, the spatial propagating characteristics of the three types of PLC deformation bands are observed and analyzed. The evolutions of the propagating velocity for type A and B bands are discussed with respect to different tensile strains in the 3mm thick specimens. At the same tensile strain, the power law relationship between band propagating velocity and applied strain rate is also obtained. Contrasting the serrated stress-time curves with the position-time plots, the relationship between the macroscopic spatiotemporal behaviors is compared for the PLC effect. The influence of specimen thickness to the spatial correlation of PLC deformation bands is also discussed.