Electromechanical Breakdown
When a dielectric material is subjected to an electric field electrostatic compressive stresses are developed, charges of opposite nature are induced on the two opposite surfaces of the material and hence a force of attraction is developed and the specimen is subjected to electrostatic compressive forces and when forces exceed the mechanical withstand strength of the material the material collapses due to the reduction in thickness (Which will not be balanced by elastic restoring force) and hence material would continue to shrink until breakdown.
If the thickness of the specimen is ‘do‘and is compressed to a thicker ‘d’ under an applied voltage ‘v’ then the electrically developed compressive strength in equilibrium.
