• Journal of the Korean Ceramic Society
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• v.23 no.3
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• pp.15-20
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• 1986

Formation of powders and electromechanical coupling factor of $Pb(Mn_{1/3} Sb_{2/3})_{0.08} Ti_{0.495}Zr_{0.425}O_3$ by hydro-thermal synthesis are described. The hydrothermal reactions each were accomplished at 12$0^{\circ}C$~25$0^{\circ}C$ for 5hours and sintering was accomplished at 1, .20$0^{\circ}C$ for 1hours. The PZT powders by hydrothermal synthesis were formed above 16$0^{\circ}C$ and the forms were cubic types. The ratio of grain size of sintered sample to powder was slowly decreased with the rising of hydrothermal reactino temperature but decreased rapidly above 22$0^{\circ}C$ Sintering density was decreased with the rising of hydrothermal reaction temperature above 16$0^{\circ}C$ but dielectric constant was increased. Electromechanical coupling factor $K_P$ was almost constant at 16$0^{\circ}C$~24$0^{\circ}C$ range and the value of $K_P$ was about 0.43-0.45.

• Journal of the Korean Ceramic Society
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• v.52 no.1
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• pp.77-82
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• 2015

The effect of the electrode type on the dielectric and piezoelectric properties of $Pb(Mg_{1/3}Nb_{2/3})O_3-PbZrO_3-PbTiO_3$ (PMN-PZT) single crystals was investigated in an effort to improve their properties for various piezoelectric applications. First, three different types of PMN-PZT single crystals [PMN-PZT-A (piezoelectrically soft type; dielectric constant ~ 10,000), PMN-PZT-B (piezoelectrically soft type; phase-transition temperature between the rhombohedral and tetragonal phases ($T_{RT}$) ~ $145^{\circ}C$), PMN-PZT-C (piezoelectrically hard type; high mechanical quality factor ($Q_m$) ~ 1,000)] were fabricated using the solid-state single crystal growth (SSCG) method. Then, four different types of electrodes [sputtered Au, sputtered Cr/Au, sputtered Ti/Au, and fired Ag] were formed on the single crystals, and their dielectric and piezoelectric properties were measured. The single crystals with a sputtered Ti/Au electrode showed the highest dielectric and piezoelectric constants but the lowest coercive electric field ($E_C$). The single crystals with a fired Ag electrode showed the lowest dielectric and piezoelectric constants but the highest coercive electric field ($E_C$). This dependence on the type of electrode was most significant in the piezoelectrically hard PMN-PZT-C single crystals. However, the effects of the electrode type on the phase transition temperatures ($T_C$, $T_{RT}$) and dielectric loss were negligible. These results clearly demonstrate that it is important to select an appropriate electrode so as to maximize the dielectric and piezoelectric properties of single crystals in each type of piezoelectric application.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.11
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• pp.921-925
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• 2000

Characteristics of Pb(Mg, Nb)O$_3$-Pb(Zr, Ti)O$_3$system thick films fabricated by a screen printing method were investigated. The buffer layer were coated with various thickness of Ag-Pd by screen printing to investigate the effect as a diffusion barrier and deposited Pt as a electrode by sputtering on Ag-Pb layer. The printed thick films were burned out at 650$\^{C}$ and sintered at 950$\^{C}$ in O$_2$condition for each 20, 60min after printing with 350mesh screen. The thickness of piezoelectric thick film was 15∼20㎛ and Ag-Pb layer acted as a diffusion barrier above 3㎛ thickness. The PMN-PZT thick films were screen printed on Pt/Ag-Pb(6m) and sintered by 2nd step (650$\^{C}$/20min and 950$\^{C}$/1h) using paste mixed PMN-PZT and binder in the ratio of 70:30, and the remnant polarization of thick film was 9.1$\mu$C/㎠ in this conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.25-33
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• 1994

Temperature dependences of the remanent polarization $P_{\gamma}$/(T), effective birefringence ㅿｎ(T). dielectric constant K(T) and quadratic electro-optic coefficient R(T) of the two-stage sintered xBa(La$_{1/2}$Nb$_{1/2}$)O$_3$Pb$(Zr_{y}Ti_{1-y})O-{3}$(x=0.085, 0.09, 0.40$\leq$y$\leq$0.70)ceramics were investigated. Increasing the PbZrO$_3$ contents, the crystal structure of a specimen was varied from tetragonal and rhombohedral to cubic, and the phase transition was showed a diffuse phase transition(DPT) characteristics. Especially. in the compositions which located on the PE-FE phase boundary were showed a discrepancy between curie temperature and temperature range which a macroscopic polarization and a effective birefringence were disappeared.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.391-395
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• 2000

In this study, the temperature coefficient of resonant frequency(TC $F_{r}$), dielectric and piezoelectric properties of Pb[(S $b_{1}$2/N $b_{1}$2/)$_{0.0035}$-(M $n_{1}$3/N $b_{2}$3/)$_{0.0065}$-(Z $r_{x}$ $Ti_{1-x}$ )$_{0.90}$] $O_3$ceramics is investigated with Zr/Ti ratio. The dielectric constant and electromechanical coupling factor( $k_{p}$) showed the highest values of 1257, 0.562 respectively when the Zr/Ti ratio is 49.5/50.5. The mechanical quality factor( $Q_{m}$) is the lowest value of 713 when the Zr/Ti ratio is 49.5/50.5, and increased with the decrease of the Zr/Ti ratio. The temperature coefficient of resonant frequency(TC $F_{r}$) change abruptly at the morphotropic phase boundary(MPB), which is between the rhombohedral phase with highly negative TC $F_{r}$ of -106ppm/$^{\circ}C$ and the tetragonal phase with highly positive TC $F_{r}$ of +64pp $m^{\circ}C$ as Zr/Ti ratio changes from 50/50 to 49.5/50.5.50.5..5.50.5.5.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.2
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• pp.191-196
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• 2023

In this paper, for the application of ultrasonic cleaners for cleaning dentures and transparent braces, Pb(Mn_1/3Nb_2/3)O₃-Pb(Ni_1/3 Nb_2/3)O₃-Pb(Zr,Ti)O₃ [PMN-PNN-PZT] system ceramics were manufactured and their dielectric and piezoelectric properties were investigated. Overall the best properties suitable for the device applications such as ultrasonic cleaner were obtained from the ceramics sintered at 920℃: bulk density of 7.8 g/cm³, the dielectric constant (ε_r) of 1,689, piezoelectric charge constant (d₃₃) of 433 pC/N, planar electromechanical coupling factor (k_p) of 0.64, mechanical quality factor (Qm) of 835, S₁₁^E of 13.37 (10^-12 N/m²), and Curie temperature of 315℃ By using the physical properties of this composition, the ultrasonic cleaner was designed and simulated using the commercial ATILA software. For the three-layered ceramics with the dimension of 25 mm × 25 mm × 2.5mm, an excellent displacement of 8.998 10^-3 m) and the sound pressure of 147.68 dB were recorded.

• Journal of Sensor Science and Technology
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• v.4 no.4
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• pp.75-80
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• 1995

In order to fabricate the piezoelectric thin film of the PZT-PNN ternary compound, the metal alkoxides were used as starting materials. The electrical and crystalline properties of the thin film were evaluated. The X- RD study shows that the crystallization of the film is optimized at $550^{\circ}C$ of sintering temperature. According to the D-E hysterisis curve, the coercive field is 28.8 kV /cm, and the remanent polariztion is $18.3\;{\mu}C/cm^{2}$. The break down voltages of the thin films are $76.0\;{\sim}\;27.0\;MV/m$. When the sintering temperature is raised, the break down voltage is lowered. As a result of measuring the C-V characteristic curve of the ternary compound piezoelectric thin film, the relative dielectric constants are 406 for the composition (50:40:10), 1084 for the composition (50:30:20), 723 for the composition (45:35:20) and 316 for the composition (40:40:20).

• Fire Science and Engineering
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• v.9 no.2
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• pp.29-36
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• 1995

In this study, the effect of Mn $O_2$ additive on the electrical characteristics of PZN-PSS-PZT Pyroelectric materials for the fire detactor was studies. PZT ceramics used this experimental is 4 composite system $[$Pb(Z $n_{1}$3/ N $b_{2}$3/) $O_3$＋Pb(S $n_{1}$3/ S $b_{2}$3/) $O_3$＋PbTi $O_3$＋PbZr $O_3$$]$The dielectric constants and dissipation factors decreases as to Mn $O_2$ concentration increases. At the Mn $O_2$ 0.5($\omega$t%), Pyroelectric coefficient shows 8(10$^{-8C}$$\textrm{cm}^2$$^{\circ}C$) which have the highst value among other additive contents. It is found that output voltage shows maximum peck at Mn $O_2$0.7($\omega$t％) is associated with the higher pyroelectric coefficient and Lowered dielectric constant.t.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1337-1338
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• 2007

In this study, in order to develop low temperature sintering ceramics for multilayer piezoelectric actuator, 0.07Pb$(Mn_{1/3}Nb_{2/3})O_{3}-xPb(Ni_{1/3}Nb_{2/3})O_{3}-(0.93-x)Pb(Zr,Ti)O_{3}$ ceramics system were fabricated using $Li_{2}CO_{3}-Bi_{2}O_{3}$-CuO sintering aids and the specimens were sintered at $930^{\circ}C$. Thereafter their piezoelectric and dielectric characteristics were investigated with the amount of PNN substitution. At 9[mol%] PNN substitution, electromechanical coupling factor (kp), mechanical quality factor (Qm) and piezoelectric constant ($d_{33}$) showed the optimum value of 0.60, 1323 and 387pC/N, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.173-176
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• 2004

The piezoelectric ceramics for AE sensor piezoelectric devices are desirable to possess higher resonance vibrations. The compositions of $0.9Pb(Zr_xTi_{1-x})O_3-0.1Pb(Mn_{1/3}Nb_{1/3}Sb_{1/3})O_3$ (PZT-PMNS) in this work are selected for obtaining especially large electromechanical coupling factor, high mechanical quality factor and high Curie temperature. This ceramic has higher piezoelectric activity and higher electromechanical coupling factor, but the ceramic has lower Curie temperature. The piezoelectric and dielectric characteristics of PZT-PMNS ternary system are investigated as functions of $Ti^{2+}$, $Zi^{2+}$ mol rate. As the results, MPB(morphotropic phase boundary) in this piezoelectric ceramic is x=0.522. Resonance vibrations of PZT ceramics are investigated as ball-bearing drop test. For the use of AE sensor that driving with pre-amplifier, filter circuit after packed this ceramic and an elastic body.