Abstract:
By considering the conducting crack as the result of electrical break down, this paper derives a storage energy formula when there is a crack in contact with and perpendicular to a surface of the ferroelectric block. Then the driving energy per unit area of the crack developing surface is deduced. When this energy is greater than the surface energy of the ferroelectric ceramic, the process of breakdown could be developed. From this condition, the critical voltage or shockwave velocity can be derived. Lastly, the results of this paper and others are compared as well.