Investigation into Characteristics of Portevin-Le Chatelier Effect of an Al-Mg Alloy

In this study, the plastic instabilities associated with the Portevin-Le Chatelier (PLC) and their effects on the mechanical properties and the fracture surfaces have been investigated for AA 5083. Tensile tests were performed at various temperatures and strain rates in order to do so. Then, serrated and smooth yielding domains were determined in Ln  $ \dot{\upvarepsilon } $ -1/T diagram. The stress-strain curves related to the serrated domain show the values of flow stress decreases by increasing the strain rate at a constant temperature. In addition, the plot of critical strain versus imposed strain rate indicates an inverse manner at very low strain rates. It is confirmed that the type of PLC bands alters the values of ductility. Also, scanning electron microscopy (SEM) was utilized to study the fracture surfaces of tensile test specimens. SEM images show that PLC effect or dynamic strain aging changes the fracture type and the feature of failure.