An interface testing cell for multi-stress ageing

With the wider introduction of solid insulating material combinations in components, problems have become apparent at their interfaces. In order to study and to test interfaces, testing cells are being developed in which an electric field can be applied partly along the interface of two solid dielectrics. The present paper presents a sample cell that is suitable for two materials that can rub along each other and make discharging likely at the interface. This effect is believed to have contributed to several major failures. The cell is also fit for investigating environmental influences. The paper outlines interface degradation; describes the requirements, design and use of the sample cell; reports the first exploratory experiments