VERFAHREN UND VORRICHTUNG ZUR PRUEFUNG VON ELEKTRISCH ISOLIERENDEN SCHUTZSCHICHTEN AUF METALLTEILEN

摘要

The process and the device are used for testing electrically insulating protective coatings on metal parts which, together with a backplate electrode, form an electrolytic cell to which current or voltage is applied. The process and device are characterized by the fact that, for quantitative testing of the protective coating, a stabilized current impulse or a constant voltage impulse of short duration is applied and the variations with time in the voltage applied to the electrolytic cell, or in the current flowing through the cell, is recorded during and shortly following the impulse. In this way it is possible to detect faults in coatings of a size which is less than 10<-6> of the total surface.