Electric signals from plastic deformation in metals. Monitoring intermittent plastic flow in metals with an electric field sensor

Dislocations reaching the metal surface and producing slip steps during plastic deformation generate surface charge density pulses that can be monitored with an electric field sensor. This is a simple way to study the statistics and details of dislocation avalanches thus giving further insight into the complex processes related to plastic flow. Intermittency and load drop behaviour (Portevin-Le Chatelier effect) is reflected in the transients shape and statistics. From an applied point of view this method can be adapted to monitor the damage development in metal structures under load in a contact free way.