Electrical fatigue failure in (Na 1/2 Bi 1/2 )TiO 3 –BaTiO 3 relaxor ceramics

Many devices containing ferroelectric ceramics are subjected to different loading conditions and cycles, and lack of adequate long‐term reliability studies is a major concern. Here, we explore a (Na 1/2 Bi 1/2 )TiO 3 –BaTiO 3 solid solution and study electrical fatigue as a function of amplitude, temperature, frequency, and static offset voltage ( dc bias). This is expected to act as a guide for other similar material systems. Empirical relationships to quantify the dependence of fatigue on these parameters are presented. With electric field amplitude ( E max ), the number of cycles to fatigue failure ( N fail ) varies as: E max × N fail a = C , where a and C are constants whose values are different when the field amplitude is below and above the coercive field. With changes in temperature, N fail exhibits an activated behavior and follows an Arrhenius relationship with an activation energy of 0.7 eV at an amplitude above the coercive field. In the absence of self‐heating, a power law relationship is observed between N fail and frequency of fatigue cycles at an amplitude above the coercive field. On applying a dc bias, N fail increases by an order of magnitude, an observation that is attributed to domain switching effects. A majority of the above‐mentioned effects have been explained in terms of the motion of domain walls under a given fatigue condition and their interaction with point defects.