• Proceedings of the Korean Magnestics Society Conference
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• 2005.12a
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• pp.152-153
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• 2005

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.208-209
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• 2006

Sinterability and microwave dielectric properties of the $Zr1-x(Zn_{1/3}Nb_{2/3})xTiO_4$(x=4, 6) system ceramics have been investigated as functions of zinc-borosilicate(ZBS) glass contents and amount of $Zn_{1/3}Nb_{2/3}O_2$ substitution with a view to applying the composition to LTCC technology. The addition of 25 wt% ZBS glass ensured successful sintering below $925^{\circ}C$. With increasing ZBS glass and $Zn_{1/3}Nb_{2/3}O_2$ contents increased dielectric constant and sinterability but addition ZBS glass decreased the quality factor significantly due to the formation of an excessive liquid and second phases. The sintered $Zr4(Zn_{1/3}Nb_{2/3})6TiO_4$ system ceramics at $925^{\circ}C$ with 25 wt% ZBS glass demonstrated 27.7 in dielectric constant (${\varepsilon}_r$), 3,850 m quality factor($Q{\times}f_0$), and +6 ppm/$^{\circ}C$ in temperature coefficient of resonant frequency($\tau_f$).

• Electrical & Electronic Materials
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• v.9 no.7
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• pp.652-659
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• 1996

Sintering characteristics and electrical properties of xPb(Mg$_{1}$8/Te$_{1}$8/Mn$_{1}$4/Nb$_{1}$2/) $O_{3}$-(1-x) Pb (Zr$_{1}$2/ $Ti_{1}$2/) $O_{3}$ (x=0.075, 0.1, 0.125) ceramics are investigated. A sintering temperature of ceramics could be reduced to 950.deg. C by a reaction between PbO and B site compound material. The physical properties of 0.1Pb(Mg, Te, Mn, Nb) $O_{3}$ - 0.9Pb(Zr, Ti) $O_{3}$ bulk ceramic with 3wt% glass frit(0.857PbO-0.143W $O_{3}$) were following : den = 7.95 g/cm$^{3}$, T$_{c}$=340.deg. C, .epsilon.$_{33}$= 754, k$_{31}$=0.3 and Q.=1780. The 3-layer piezoelectric transformer by using a tape casting method showed a good monolithic structure, and its voltage setup ratio was 2.5 times higher than that of a single device by using bulk ceramics.s.s.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.104-104
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• 2008

Ti과 Ti합금은 우수한 생체적합성을 가지고 있어 생체용 재료로 널리 이용되고 있지만 기계적 물성 및 합금원소의 세포 독성에 대한 문제가 제시되고 있다. 본 실험에서는 세포 독성이 없는 Nb과 Zr을 합금원소로 하여 Ti-Nb-Zr 3원계 합금을 제조하고 생체적합성을 향상시키기 위해 양극산화법을 이용하여 $TiO_2$ nanotube를 형성하고 AC임피던스를 통하여 그 특성을 조사하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05b
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• pp.123-123
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• 1992

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.39.1-39
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• 2003

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.228-229
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• 2006

본 연구에서는 초음파 모터 등의 고출력 액츄에이터에 응용 가능한 $04Pb(Ni_{1/3}Nb_{2/3})O_3-6Pb(Zr_xTi_{1-x})O_3$ 조성시스템에 소결온도를 달리하여 압전, 유전특성 및 미세구조에 관해 고찰하였다. 본 조성을 $1200^{\circ}C$ 온도에서 2, 4, 6, 8시간 소결하여 시편을 제조하였으며 이의 결정구조 및 미세조직을 분석하였다. 소결시간 증가에 따라 전기기계결합계수와 기계적품질계수는 증가하였으며, 압전상수는 Zr(Zr+Ti)비 0.390까지 증가하였으나 그 이상 증가함에 따라 감소하였다. 압전특성은 $1200^{\circ}C$에서 4시간 소결한 Zr=0.390인 조성에서 ${\varepsilon}_r$ = 4487, $k_p$ = 0.72. $d_{33}$ = 710, $Q_m$ =109의 우수한 특성을 나타내었다.

• Journal of the Korean Ceramic Society
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• v.25 no.5
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• pp.488-494
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• 1988

Effects of MnO2 addition on themicrostructure, dielectric and piezoelectric properties of Rhombohedral, Tetragonal and Morphotropic phase boundary(MPB) in Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3 system were investigated and respectively the amount of MnO2 addition was 0, 0.2, 0.5, 1.0, 3.0wt%. In the tetragonal region, compared with the Rhombohedral and Morpotropic phase boundary, Mechanical quality factor(Qm), Curie temperature(Tc) and Dissipation factor were promoted by addition of MnO2. According to the results of the microstructure, dielectric and piezoelectric properties, the solid solution range of MnO2 addition in this system was 0.2-0.5wt%.

• Journal of the Korean Ceramic Society
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• v.26 no.4
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• pp.568-574
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• 1989

Effect of PbO addition on sintering and piezoelectric properties at 0.45Pb(Ni1/3Nb2/3)O3-0.40PbTiO3-0.15PbZrO3 composition which is tetragonal phase was investigated. In this composition, Porosity and dielectric constant were increased with excess PbO addition, but Kp and d31 was not changed. These variation of physical properties could be interpreted as composition change of solid grains from tetragonal to MPB region due to amount of PbO-rich liquid changing.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.799-801
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• 1988

This paper was studied on the effects of Ca-La-Nb substitution and Zr/Ti ratio variation to Pb(Zr, Ti)$O_3$ system on structural, electrical, optical and sound level characteristics in order to develope the piezoelectric and electrooptic ceramic devices. Also the specimens were prepared by the two stage sintering technique. The molecular formular was X($CaO{\cdot}1/4La_{2}O_{3}{\cdot}1/4Nb_{2}O_{5}){\cdot}(1-X)Pb(Zr_{Y}Ti_{1-Y})O_{3}$(x=100X, y=100Y), and the variation of x was $6{\sim}12$, y was 60${\sim}$49 and second stage sintering time was 20${\sim}$40 hours. The experimental results obtained from this study are as follows : 1. The density was decreased, the grain size was increased according to increase of Ca-La-Nb substitution. 2. The crystal structure was rhombohedral in composition 6/60/40, and the crystal structure was tetragonal and cubic according to increase of Ca-La-Nb substitution. 3. The Ca substitution of PZT system enhanced the sintering property. The Pb site vacancy resulting from the substitution of La-Nb increased the dielectrical constant, the piezoelectric charge constant, the dielectric loss and decreased the coercive field. 4. The resistivity of PZT system which has the P type conduction mechanism increased according to substitution of La-Nb because of the substituent acting as donor. 5. The PZT ceramics varied from ferroelectric substance according to increase of Ca-La-Nb substituent. The coercive field and saturation remanent polarization decreased, and at last straight line according to increase of La-Nb substitution. 6. The amount of Ca-La-Nb substitution to improve the light transmittance of speciment was 10 mol%, the Zr/Ti ratio was 49/51, and the second stage sintering time was 40 hours. 7. According to Ca-La-Nb substitution, the specimens was to be transparent. The 7.5/51/49 specimen was suitable for transparent sound vibrator because it had 58% light transmittance (thick 0.2[mm], wave length 700[mm]) and 48% electromechanical coupling factor.