Relaxor properties of Ba(Zr,Ti)O3 ceramics

摘要: BaZr x Ti 1-x O 3 is a possible candidate as environmental friendly electroceramic material (Pb-free ferroelectric) due to its high dielectric and piezoelectric constants ferroelectric properties in temperature range which can be tuned by the composition. Its change from full behavior (x=0; BaTiO ) with sharp ferro-para phase transition relaxor state (for 0.10≤x≤0.35), when structure pseudo-cubic has strong diffuse character frequency-relaxation kHz range. In present work, cross-over composition 0.1 0.9 was investigated. The ceramics have been prepared via solid reaction; optimum parameters for calcination sintering order obtain pure perovskite good densification found. dependence of constant shows small shift corresponding maximum permittivity (1-2) °C frequency 1 Hz÷1 MHz. losses are smaller than 30% temperatures below 130 °C, slight increasing at low temperatures. real part follows Curie-Weiss law frequency-dependent constants. spectroscopy data show least two relaxation processes: thermally-activated one characteristic low-frequency f<100 Hz temperature-independent f≥100 Hz.