PROCESSING AND PROPERTIES OF Na0.5Bi0.5TiO3 PIEZOELECTRIC CERAMICS MODIFIED WITH La, Mn AND Fe

Although a great deal of work has been done to understand defect chemistry in "soft" and "hard" PZT-based materials, there is little understanding of how defect chemistry influences the properties of lead-free piezoelectric materials. This paper reports a systematic investigation of doping on the ferroelectric and piezoelectric properties in Na 0.5 Bi 0.5 TiO 3 (NBT)-based ceramics. NBT-based ceramics have been synthesized by traditional solid state routes using several different dopants including lanthanum, manganese, and iron in 1 mol%. The addition of iron and manganese lead to an increase in the coercive field (E c ), a decrease in the piezoelectric coefficient (d33), and an increase in the thermal depoling temperature (T depole ), similar to the behavior of "hard" PZT. Lanthanum, on the other hand, leads to a decrease in the E c , an increase in d33, and a decrease in T depole similar to that seen in "soft" PZT.

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Large electro-strain signal of the BNT–BT–KNN lead-free piezoelectric ceramics with CuO doping

Journal of Advanced Dielectrics ◽

10.1142/s2010135x1950022x ◽

2019 ◽

Vol 09 (03) ◽

pp. 1950022 ◽

Cited By ~ 4

Author(s):

Zhi-Hao Zhao ◽

Rui-Fang Ge ◽

Yejing Dai

Keyword(s):

Transition Temperature ◽

Solid State ◽

Room Temperature ◽

Ferroelectric Phase ◽

Piezoelectric Properties ◽

The Other ◽

Lead Free ◽

State Process ◽

Relaxor State ◽

Strain Signal

This paper investigates a system of 0.93[Formula: see text][Formula: see text]TiO3–0.06BaTiO3–0.01[Formula: see text][Formula: see text]NbO3–[Formula: see text]CuO (BNT–BT–KNN–[Formula: see text]CuO, [Formula: see text][Formula: see text]mol.%) ceramics, which were fabricated by the conventional solid-state process through the granulation of vacuum freeze drier. The results show that the CuO doping made a significant enhancement on the piezoelectric properties of the BNT–BT–KNN ceramics. With the doping of CuO, the transition temperature between ferroelectric phase and ergodic relaxor state is reduced to near room temperature, resulting in pinched [Formula: see text]–[Formula: see text] loops and “sprout” shape [Formula: see text]–[Formula: see text] curves. For the composition with [Formula: see text], a high unipolar strain of 0.39% under 5[Formula: see text]kV/mm contributes a large [Formula: see text][Formula: see text]pm/V at room temperature, which is competitive with the other BNT-based ceramics.

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Ferroelectric and Piezoelectric Properties of (1-x)BaTi0.8Zr0.2O3-xBa0.7Ca0.3TiO3 Ceramics Prepared by Sol-Gel Technique

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.148-149.1480 ◽

2010 ◽

Vol 148-149 ◽

pp. 1480-1485 ◽

Cited By ~ 2

Author(s):

Zhong Wen Tan ◽

Wei Guo Fu ◽

Xiang Yun Deng ◽

Ren Bo Yang ◽

Xiao Fen Guan ◽

...

Keyword(s):

Dielectric Constant ◽

Solid State ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Sol Gel ◽

Piezoelectric Response ◽

Maximum Dielectric Constant ◽

Gel Technique ◽

Sintered Temperature ◽

Ferroelectric And Piezoelectric Properties

The(1-x)BaTi0.8Zr0.2O3-xBa0.7Ca0.3TiO3 ceramics have been prepared by sol-gel technique, where x is from 0.2 to 0.6. It reveals that the dense ceramics can be obtained when the sintered temperature is above 1250°C. It is lower than that of solid state reaction ceramics. In particular, when x=0.3, at which is near the MPB composition, the ferroelectric and piezoelectric properties are more excellent than the others. The maximum dielectric constant is above 9000, which can be observed in the butterfly shape curves of dielectric constant as a function of electric field. The maximum piezoelectric coefficient d33 can reach 400 pm/V, and it is obtained from the piezoelectric response loops.

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Sintering Temperature Effect on Ferroelectric and Piezoelectric Properties of Lead-Free Piezoelectric (K0.5Na0.5)NbO3 Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.994 ◽

2011 ◽

Vol 239-242 ◽

pp. 994-997 ◽

Cited By ~ 1

Author(s):

Chien Min Cheng ◽

Ming Chang Kuan ◽

Kai Huang Chen ◽

Chia Chi Shih ◽

Jiann Sheng Jiang

Keyword(s):

Solid State ◽

Bulk Density ◽

Ceramic Sample ◽

Electromechanical Coupling ◽

Piezoelectric Properties ◽

Sintering Temperature ◽

Lead Free ◽

Nominal Composition ◽

Solid State Sintering ◽

Ferroelectric And Piezoelectric Properties

Lead-free potassium sodium niobate ceramic, with the nominal composition of K0.5Na0.5NbO3, were synthesized by conventional solid state sintering, and its dielectric, ferroelectric, and piezoelectric properties were characterized as a function of sintering temperature. The orthorhombic to tetragonal phase transition (TO-T) temperature of K0.5Na0.5NbO3ceramic sample was about 220°C, and its Curie temperature was about 420°C. The high bulk density was obtained for all compositions by solid state sintering in air. Bulk density was increased with temperature and it reached to 4.4 g/cm3. The K0.5Na0.5NbO3ceramic sample sintered at 1100°C was optimized densification properties. In addition, the ferroelectric loop and dielectric characteristics dependence of different sintering temperature for K0.5Na0.5NbO3ceramic sample was obtained. Finally, we found that the piezoelectric constant (d33) was 160 pC/N, high remanent polarization (Pr) was 33mC/cm2, and high electromechanical coupling coefficients (kP) was about of 45%.

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Preparation and Characterization of Lead-Free Piezoelectric Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.492.189 ◽

2011 ◽

Vol 492 ◽

pp. 189-193

Author(s):

Qiang Chen ◽

Jin Xu Li ◽

Li Hui Zhang ◽

Yang Bai ◽

Yan Jing Su ◽

...

Keyword(s):

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Sintering Temperature ◽

Piezoelectric Materials ◽

Piezoelectric Ceramics ◽

Lead Free ◽

Practical Applications ◽

Structure Density ◽

Traditional Ceramics

(K,Na)NbO3-based piezoelectric ceramics are promising candidates for practical applications of lead-free piezoelectric materials due to their excellent piezoelectric properties. In this paper, lead-free piezoelectric ceramics (K0.44Na0.52Li0.04)(Nb0.86Ta0.10Sb0.04)O3(KNL-NTS)were successfully fabricated by traditional ceramics processing. The effects of sintering temperature on the structure, density and electrical properties of KNL-NTS ceramics were investigated. Crystal phases of both calcined powders and KNL-NTS ceramics have orthorhombic structure similar to that of KNbO3 ceramics. The piezoelectric coefficient first increases and then decreases with sintering temperature in the 1100-1180 °C range. KNL-NTS ceramics sintered at 1160 °C shows the maximum piezoelectric coefficient of about 199 pC·N-1and the maximum remnant polarization of 18.75 μC·cm-2, with the corresponding 10.95 kV·cm-1coercive field and 4.74 g/cm3density.

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Study on Dielectric and Ferroelectric Properties of Gd-Doped Sr2Bi4Ti5O18 Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.328-330.1131 ◽

2011 ◽

Vol 328-330 ◽

pp. 1131-1134

Author(s):

Qian Chen ◽

Zhi Jun Xu ◽

Rui Qing Chu ◽

Yong Liu ◽

Ming Li Chen ◽

...

Keyword(s):

Piezoelectric Properties ◽

Ferroelectric Properties ◽

Solid State Reaction Method ◽

Lead Free ◽

Structural Ceramics ◽

Conventional Solid State Reaction ◽

Reaction Method ◽

Maximum Value ◽

Pure Bismuth ◽

Ferroelectric And Piezoelectric Properties

Lead-free piezoelectric ceramics Sr2Bi4-xGdxTi5O18 were prepared by conventional solid-state reaction method. Pure bismuth layered structural ceramics with uniform gain size were obtained in all samples. The effect of Gd-doping on the dielectric, ferroelectric and piezoelectric properties of Sr2Bi4Ti5O18 ceramics were also investigated. It was found that that Gd3+ dopant gradually decreased the Curie temperature (Tc) with the lower dielectric loss (tand) of SBTi ceramics. In addition, Gd-doping with appropriate content improved the ferroelectric and piezoelectric properties of the SBTi ceramics. The piezoelectric constant (d33) of the Sr2Bi3.9Gd0.1Ti5O18 ceramic reached the maximum value, which is 22 pC/N. The results showed that the Sr2Bi4-xGdxTi5O18 ceramic was a promising lead-free piezoelectric material.

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Mechanochemically-Assisted Synthesis of Lead-Free Piezoelectric CaZrO3-Modified (K,Na,Li)(Nb,Ta)O3-Solid Solution

Ceramics ◽

10.3390/ceramics1020024 ◽

2018 ◽

Vol 1 (2) ◽

pp. 304-318 ◽

Cited By ~ 3

Author(s):

Kristian Radan ◽

Brigita Kmet ◽

Silvo Drnovšek ◽

Uroš Prah ◽

Tadej Rojac ◽

...

Keyword(s):

Thermal Analysis ◽

Solid State ◽

Processing Time ◽

Piezoelectric Properties ◽

Mechanochemical Activation ◽

Solid State Synthesis ◽

Lead Free ◽

Compositional Homogeneity ◽

Lower Temperature ◽

Conventional Solid State Synthesis

Lead-free piezoelectric 0.95(Na0.49K0.49Li0.02)(Nb0.8Ta0.2)O3–0.05CaZrO3 with 2 wt % MnO2 addition was prepared using mechanochemically-assisted solid-state synthesis. Upon mechanochemical activation of the mixture of reagents partial amorphization occurs which contributes to a significantly lower temperature of completion of the solid-state reaction, ~600 °C as opposed to ~700 °C for the conventional solid-state synthesis as determined by thermal analysis. The ceramic specimens prepared by the mechanochemically-assisted route exhibit improved compositional homogeneity and slightly enhanced piezoelectric properties, achieved in a considerably shorter processing time compared to the conventional solid-state synthesis route, which was studied as a reference.

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Comparative study on the performance of piezo-active 1–3-type composites with lead-free components

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21600031 ◽

2021 ◽

pp. 2160003

Author(s):

Ashura N. Isaeva ◽

Vitaly Yu. Topolov

Keyword(s):

Single Crystal ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Volume Fraction ◽

Lead Free ◽

Figures Of Merit ◽

Piezoelectric Energy ◽

Harvesting Systems ◽

Porous Matrices ◽

Large Anisotropy

Piezoelectric properties and related figures of merit are studied in novel 1–3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coefficient [Formula: see text]. Relationships between the piezoelectric properties and the set of figures of merit are analyzed for the 1–3 and 1–3–0 composites that contain the same single-crystal and polymer components. For a composite characterized by 1–3–0 connectivity, an influence of a porous piezo-passive matrix on the figures of merit and their volume-fraction behavior is considered additionally. A large anisotropy of figures of merit is observed in the 1–3–0 composite with specific porous matrices. A diagram is put forward to show volume-fraction regions of the large anisotropy of figures of merit of the studied 1–3–0 composite. Due to large figures of merit and their considerable anisotropy, the studied lead-free composites can be applied in piezoelectric energy-harvesting systems, sensors, transducers, and so on.

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