Detachment of Conductive Coatings by Pulsed Electromagnetic Field

Abstract

The paper presents results of studies on the detachment of conductive coatings from the metal substrate by pulsed electromagnetic field (PEMF). It is known that at the boundary of a metal substrate and an electrically conductive coating having different electrical conductivities sharp changes of PEMF strength arise. This effect has been used to remove a copper layer from a steel substrate. Experimental studies were carried out in the Riga Technical University (Latvia), West Saxony University of Applied Science Zwickau, (Germany) and the Samara Aerospace University (Russia). Generators of pulsed current with power capacity from 1 to 60 kJ with discharge rates from 10 to 100 kHz were used. Treatment of coatings was performed using both flat and cylindrical inductors. The influence of a number of factors on the efficiency of the separation of conductive coating (Cu, Al), such as the thickness and material properties of the coating and substrate, the strength of adhesion of the coating to the substrate, the electrical parameters of the equipment and the inductor system, are shown. Examples demonstrating the main application potential of the method include: deleting of a thin conductive coating induced on metallic and non-metallic products by spraying; separation of layers of metal sheets after their joint rolling or punching; removal of conductive membranes used in the magnetic pulse compression of powders.