부산대학교 도서관

Piezoelectric ceramics of Pb 0.98 Sr 0.02 (Mn 1/3 Sb 2/3 ) 0.05 Zr 0.48 Ti 0.47 O 3 with 0.25 wt% CeO 2 , 0.50 wt% Yb 2 O 3 , and x wt% Fe 2 O 3 ( x = 0.02, 0.05, 0.1, 0.15, and 0.2) additives were synthesized using a conventional solid-state reaction. Their piezoelectric properties and, in particular their nonlinear dielectric behaviors were systematically investigated. Iron was mainly present in the form of Fe 3+ based on X-ray photoelectron spectroscopy; a small amount of the iron was reduced to Fe 2+ . Iron occupied the B-site of the perovskite structure, as shown in the refinement results. The samples displayed both “soft” and “hard” properties because Fe 3+ can be incorporated at the Mn 2+ , Zr 4+ , Ti 4+ , and Sb 5+ sites. The domain wall motion was found to be related not only to the type of deficiency but also to the grain size and grain boundary effects based on the nonlinear dielectric behaviors under alternating electric fields. The optimal overall properties of d 33 = 360 pC/N, tan δ = 0.295%, Q m = 1500, k p = 0.61, ε r = 1055, α ε = 4.574*10 −4 m/V, and tan δ = 2.76% (under 500 V/mm) were obtained for samples sintered at 1150 °C( x =0.15). [ABSTRACT FROM AUTHOR]