• Journal of the Korean Ceramic Society
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• v.25 no.4
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• pp.335-340
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• 1988

The change in microstructure and the electrical properties of Pb(In1/2Nb1/2)O3-PbTiO3 Ceramics caused by V2O5 addition were studied. The results are ; 1. interability was increased because the mass transport through the second phase formed by V2O5 addition increased. 2. ith addition of V2O5, tetragonality and Curie temperature increased. The maximum value of kp was observed when 0.5wt% of V2O5 was added. 3. he second phase formed by V2O5 accelerated the grain growth, and existed in grain boundary. Electrical properties were changed by corelations between tetragonality and the amount of second phase.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.5
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• pp.517-524
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• 1992

In this study, 0.10Pb(SbS11/2TSnS11/2T)OS13T-(0.90-x)PbZrOS13T (0.25 x 0.40) ceramics were fabricated by the atmospheric method. The sintering temperature and time were 1250[$^{\circ}C$] and 2[2hr], respectively. The structureal, dielectric and piezoelectric properties with composition of PbTiOS13T were studied. As the results of XRD ans SEM, the crystal structure of a specimen was rhombohedral, lattice constant and average grain size were decreased with increasing the contents of PbTiOS13T. Relative dielectric constant and Curie temperature were increased with increasing the contents of PbTiOS13T, 0.10PSS-0.40PT-0.50PZ specimen had the highest values of 904 and 265[$^{\circ}C$], respectively. In increasing of PbTiOS13T contents form 25[mol%] to 40[mol%], piezoelectric charge constant and electromechanical coupling factors were increased form 114[pC/N] to 142[pC/N], 17[%] to 24[%] and mechanical quality factor were decreased with increasing the contents of PbTiOS13T. In the 0.10PSS-0.40PT-0.50PZ specimens, those values were 14.2[kV/cm] and 9.43[x10S0-6TC/cmS02T], resectively.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.498-501
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• 2001

The effects of MnO$_2$ addition on the piezoelectric properties in 0.9Pb($Mg_{1/3}Nb_{2/3}$)$O_3$-0.1Pb$TiO_3$ relaxor ferroelectrics were studied in the ferroelectricity-dominated temperature range from -4$0^{\circ}C$ to 3$0^{\circ}C$. Dielectric, piezoelectric properties and electric-field- induced strain were examined to clarify the effect of MnO$_2$ addition. As the added amount of MnO$_2$ increase. dielectric and piezoelectric properties of Pb(Mg$_{1/3}$ Nb$_{2/3}$O$_3$ became harder. From the experimental results, it was suggested that Mn behaves as a ferroelectric domain pinning element.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.330-330
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• 2008

$Fe_2O_3$ added Pb$(Ni_{1/3}Nb_{2/3})O_3-PbTiO_3-PbZrO_3 $ (PNN-PT-PZ) ceramics were produced in order to use them as a bimoph acturator for energy harvesting. Especially, the 0.25 wt% $Fe_2O_3$ added 0.4PNN-0.357PT-0.243PZ, having the composition of morphotropic phase boundary, showed good piezoelectric properties of $d_{33}$ of 810 pC/N, $k_p$ of 77% and $Q_m$ of 55 along with a high Curie temperature of $210^{\circ}C$. A bimorph actuator, composed of the two piezoelectric layers bonded together with a phosphorous bronze layer as a central metallic electrode, was successfully fabricated. The bimorph actuator, vibrated with a 1.3 mm amplitude at 68 Hz, produced high electric power of approximately 60 mW.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.211-211
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• 2003

PbTiO$_3$ 씨앗층을 이용하여 완화형 강유전체 Pb(Mg$_{1}$3/Ta$_{2}$3/)O$_3$ (PMT) 박막의 페로브스카이트 상안정화와 열처리 조건에 따른 미세구조변화, 이에 따른 전기적 특성 변화에 관하여 조사하였다. PbTiO$_3$ 박막을 스핀코팅법으로 3000 rpm에서 20초간(111) 방향으로 배향된 Pt / Ti / SiO$_2$/ Si 기판에 증착하여 안정화된 페로브스카이트 박막을 얻었다. 이렇게 제조된 PbTiO$_3$를 Buffer 층으로 사용하고 그 위에 Pb(Mg$_{1}$3/Ta$_{2}$3/)O$_3$를 박막을 Spin coating방법으로 증착한 후, 급속열처리 방법(RTA)으로 550- $650^{\circ}C$ 사이에서 열처리하였다. 제조된 박막의 열처리 온도에 따른 미세구조 변화와 결정성을 XRD, SEM, TEM으로 분석하였고 박막의 저온 강유전 특성을 RT66A를 이용하여 평가하였다. Pb(Mg$_{1}$3/Ta$_{2}$3/)O$_3$ 박막의 경우 씨앗층이 없는 경우에는 pyrochlore상이 주상이었지만 씨앗층을 사용한 경우 페로브스카이트 상이 주상임을 확인하였고 열처리 온도가 증가할수록 페로브스카이트상의 상대적 양이 증가함을 확인하였다. 미세구조와 상의 변화에 따른 전기적 특성 변화에 관하여 자세하게 논의할 것이다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1990.10a
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• pp.65-67
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• 1990

In this study, (0.80-x)Pb($Mg_{1/3}Nb_{2/3}$)$O_3$-$PbTiO_3$-Pb($Ni_\frac{1}{2}W_\frac{1}{2}$)$O_3$ 0.05$\leq$x$\leq$0.20) ceramics were fabricated by the mixed oxide method, the sintering temperature and time were 950∼1200[$^{\circ}C$], 2[hr], respectively. The dielectric and structural properties with composition and sintering temperature were investigated for the application as multilayer ceramic capacitors. Dielectric constant of 0.70PMN-0.2PT-0.10PNW composition with repeated calcination was increased rapidly. Increasing the Pb($Mg_{1/3}Nb_{2/3}$)$O_3$-$PbTiO_3$-Pb($Ni_\frac{1}{2}W_\frac{1}{2}$)$O_3$ contents from 0.05 to 0.20 [mol], phase transition temperature was shifted from 68 to 2[$^{\circ}C$] and dielectric constant was decreased while sintered density was increased. In the specimens containing 0.10, 0.15[mol] of PNW, dielectri constants at room temperature were exhibited the highest values 11199, 10114, respectively. Resistivity of specimens were $10^{10}$ ∼ $10^{12}$($\Omega$.m) and there was no dependence on sintering temperature and composition.

• Journal of the Korean Ceramic Society
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• v.36 no.12
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• pp.1287-1295
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• 1999

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.379-382
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• 1998

In this paper, the microwave dielectric properties of the yPb($Fe_{2/3}W_{1/3}$)$O_{3}$ - (1-y)($Pb_{x}Ca_{1-x}$)$ZrO_{3}$ system were investigated. It was found that an addition of Pb($Fe_{2/3}W_{1/3}$)$O_{3}$ promotes the grain growth, the solid solution between the Pb-based perovskite and the Ca-based perovskite and the decreasing of the sintering temperature. Especially, we found that 0.05Pb($Fe_{2/3}W_{1/3}$)$O_{3}$-0.95($Pb_{x}Ca_{1-x}$)$ZrO_{3}$ ceramic has not only lower sintering temperature but also better dielectric properties than those of the (Pb, Ca)$ZrO_{3}$ systems.

• Journal of the Korean Ceramic Society
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• v.30 no.11
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• pp.925-932
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• 1993

The perovskite phase in PZN-PMN-PT (Pb(Zn, Mg)1/3Nb2/3O3-PbTiO3) pseudoternary ceramics was stabilized by the addition of excess constituent divalent oxides (PbO, MgO and ZnO). The excess addition of 5mol% MgO or 7.5mol% PbO fully stabilized the perovskite phase. The enhanced diffuse phase transition (DPT) and the decrease in the electrical resistivity observed in the presence of excess ZnO or MgO were interpreted in terms of the additional formation of negatively charged, short-range ordered 1:1 domains with a concomitant generation of charge carriers, holes.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.2
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• pp.23-29
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• 2001

In the SP series of glasses, the formation of droplet is well done with increasing PbO. But in the case SP-1, droplet could not be observed in low concentration PbO. These results are considered that PbO does the role of a network modifier, so the crosslinking break down by $SiO_2$. But, in the glasses contained PbO above 50 mol%, glasses are formeddue to $Pb^{4+}$ ion does the role of a network former. As a result of electrical conductivity analysis for SP series of glasses, the electrical conduction is due to bipolaron at high temperature, and it is due to single polaron hopping at low temperature. In the SP series of glasses, electrical conduction mechanism coincide with the correlated-barrier hopping(CBH) model.