Effect of geometrical stress concentrators on the current-induced suppression of the serrated deformation in an aluminum–magnesium AlMg5 alloy

Аннотация

The effect of an electric current on the band formation and the serrated deformation of planar specimens made of an aluminum–magnesium AlMg5 alloy and weakened by holes is experimentally studied. It is found that the concentration of elastic stress fields and the self-localized unstable plastic deformation field near a hole decreases the critical strain of appearance of the first stress drop and hinders the currentinduced suppression of band formation and the serrated Portevin–Le Chatelier deformation. These results are shown not to be related to the concentration of Joule heat near a hole.