Effects of Cr_2O_3 doping on the electrical properties and the temperature stabilities of PNW-PMN-PZT ceramics

摘要

The ceramics with 0.90Pb(Zr_(0.50)Ti_(0.50))O_3-0.07Pb(Mn_(1/3)Nb_(2/3))O_3-0.03Pb(Ni_(1/2)W_(1/2))O_3 were prepared by adding Cr_2O_3. The effects of Cr_2O_3 doping on the phase structure, the microstructure and the electrical properties of ceramics were investigated. Meanwhile, the temperature stabilities of the resonant frequency (f_r) and the electromechanical coupling factor (K_p) were studied. The results showed that the better temperature stability could be obtained at x = 0.2 wt.% when the calcining temperature was 800℃ and the sintering temperature was 1150℃. The parameters were △f_r/f_(r25℃) = -0.17% and △K_p/K_(p25℃)=-1.39%. Moreover, the optimized electrical properties were also achieved, which were K_P = 0.54, Q_m = 1730, d_(33) = 330 pC/N, ε_r = 2078 and tan δ = 0.0052. The optimized properties make the ceramics with this composition to be a good candidate for high power piezoelectric transformers applications.