Electrical breakdown in solid and liquid insulating materials

The study of electrical breakdown in insulators has historically followed the classical segregation of materials into gases, liquids and solids. Each of these three classes were investigated separately and independently of the others. Recent progress in the area of liquids has suggested that it might be useful to look for common features between liquid and solid breakdown. With the advent of sophisticated electro-optical techniques the development of streamers can now be followed in transparent liquids and similarities in their development and those observed by other techniques in polyimeric solids become evident. In the following sections an attempt is made to point out common features of the breakdown process in solids and liquids.