Doping of BiScO₃–PbTiO₃ Ceramics for Enhanced Properties

Abstract

High-temperature piezoelectrics are a key technology for aeronautics and aerospace applications such as fuel modulation to increase the engine efficiency and decrease emissions. The principal challenge for the insertion of piezoelectric materials is the limitation on upper use temperature which is due to low Curie-Temperature (T C ) and increasing electrical conductivity. BiScO 3 -PbTiO 3 (BS-PT) system is a promising candidate for improving the operating temperature for piezoelectric actuators due to its high T C (>400 o C). Effects of Zr and Mn doping of the BS-PT ceramics have been studied and all electrical and electromechanical properties for Sc-deficient and Ti-deficient BS-PT ceramics are reported as a function of electrical field and temperature. Donor doping with Zr and Mn (in Sc deficient compositions) increased the DC-resistivity and decreased tanδ at all temperatures. Resulting ceramics exhibited saturated hysteresis loops with low losses and showed no dependence on the applied field (above twice the coercive field) and measurement frequency.

Effects of sintering atmosphere on microstructure and electrical properties of BiScO3–PbTiO3 high-temperature piezoceramics

“…Higher peaks current of S13 and S23 are observed, indicating more domain walls switching under coercive field, which is consistent with the observation of higher piezoelectric coefficient of S13 and S23. All samples show square hysteresis loops as a result of A-site vacancies effect which was proposed by Sehirlioglu et al [19]. This is consistent with the observation of EDS which indicated that all grains were of Bi-, Pb-deficiency.…”

Structure and electrical behaviors of 0.36BiScO3–0.64PbTiO3 ceramics with overdosing Bi and Pb starting materials

“…At the saturation state of the polarization (Fig. 4a), the P r and E c of the BS-PT-II ceramic sintered at 1000 C for 2 h are 43.2 mC/cm 2 and 30.9 kV/cm, respectively, higher than the previously reported values [5][6][7][8][9]15,16,26,27,30]. The switching current-electric field curve exhibits two slightly asymmetric peaks with peaks value 10 and À12 A/m 2 , respectively.…”

“…The strain behavior results indicate a bipolar strain of 0.4% and a unipolar strain of 0.23% (Fig. 4b and c), respectively, both again higher than previously reported values [5][6][7][8]15,26,27,30].…”

Thermal Depolarization in the High‐Temperature Ternary Piezoelectric System xPbTiO3–yBiScO3–zBi(Ni1/2Ti1/2)O3

“…found an increase in T C with a decrease in B‐site cationic radii for B′ = Sc (BS), In (BI), and Yb (BY). At the MPB composition (0.64 PT–0.36 BS), BS exhibited a high T C = 450°C, high piezoelectric coefficients d 33 = 335–450 pC/N, and high coupling factors k p = 0.55 close to that of PZT . Also observed in this system was a temperature independent MPB up to 300°C suggesting a wide range of temperature stability similar to PZT .…”