Temperature Effect on Fatigue Behavior of BCZT Ceramics and Defects Analysis by Synchrotron X-Ray Absorption Spectroscopy

This paper presents the effect of temperature on the electrical fatigue behavior of barium calcium zirconate titanate (Ba0.85Ca0.15Zr0.1Ti0.9O3) ceramics. Fatigue degradation and its practical applications are a significant problem in piezo/ferroelectric ceramics. Fatigue-induced domain orientations, physical damage or microcracking, and defects were studied using, X-ray diffraction (XRD), synchrotron X-ray absorption spectroscopy (XAS), and scanning electron microscope (SEM) techniques. The remnant polarization (Pr) decreased with the number of fatigue cycles, and the rate at which the decrease occurred was different for different fatigue temperatures. The weak and strong domain wall pinning effects played a major role in the Pr value with respect to the fatigue cycles. The sharp rise of Ec value at 5 x 103 cycles and the abrupt decrease of Ec values after 5 x 104 cycles could be due to the field screening effect and heat recovery of pinned domains. The abrupt decrease of Pr values after 5 x 105 cycles could be due to physical damage near the electrode interface region, and the same physical damage decreased with the increase in fatigue temperature. The near-edge X-ray absorption fine structure (NEXAFS) study was utilized to evaluate the oxygen-related defect concentration.