A method to detect mechanical cracks creation and/or propagation in insulators

Fracto-emission is the ejlection of electrons and positive ions from mater subjected to a mechanical fracture. The mechanical fracture is accompanied by the creation and/or the propagation of cracks in the mater, leading to a succession of fracto-emissions. First, we have described, through analytical equations, the amount of surface charge produced by a mechanical fracture and how it can be measured with an external measuring circuit. Then, this measuring device is used to detect the appearance of cracks and their propagation under mechanical stress. This method allows to study the electro-mechanical interactions, particularly for insulators for which the electromechanical breakdown model is being considered.