• Journal of the Korean Ceramic Society
• /
• v.38 no.9
• /
• pp.860-865
• /
• 2001

After manufacturing 2mol% CdO substitute $0.05Pb(Mn_{1/3}Sb_{2/3})O_3-0.95Pb(Zr_{0.52}Ti_{0.48})O_3$ piezoelectric ceramics powder as starting material, to manufacture green sheets using Doctor Blade method. The optimum composition of slurry was studied. Moreover, the sintering properties and the dielectric and piezoelectric properties with variation a thickness of the manufactured sheets were investigated. The optimum of slurry was investigated by the rheology with addition of additives, the sintering condition was decided by TGA. And the properties of sheet were investigated through SEM. XRD. The optimum of slurry was the stablest at dispersant 3.0 wt% to solid loading 30vol%. After, at addition of binder/plasticizer(0.75/0.25) 3.0wt%, viscosity was 7.55Pa${\cdot}$s. The dielectric and piezoelectric properties of the sheet were increased a little with the increasing of sintering temperature but were not variable with variation of sheet thickness.

• Proceedings of the KIEE Conference
• /
• 2004.07c
• /
• pp.1609-1611
• /
• 2004

압전재료의 분극공정에서 제어되는 인가전압, 유지시간 및 온도 변수들에 대한 최적의 조건을 확립하기 위해 Rosen형 안전 변압기를 설계 및 제조하여 특성분석 하였다. 분극처리를 위한 분극전계, 온도, 유지시간 등의 외부 에너지가 증가할수록 쉽게 분극되어 포화현상이 나타났으며, 140$^{\circ}C$ 이상의 온도에서 4kV/mm의 분극전계로 3분 이상 분극시키면 최대 전압 이득을 얻을 수 있다. 또한 부하저항이 증가할수록 공진주파수는 고주파 방향으로 이동하며, 공진전류가 증가하여 전압이득이 증가하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.17 no.12
• /
• pp.1314-1319
• /
• 2004

The rosen types of piezo-transformers were prepared and electrical properties were investigated in order to establish the optimum parameters in the process of polarization for ferroelectric materials. Polarization was readily originated with increasing the external energy such as an applied voltage, time, and temperature so that the planar coupling factor and voltage gain were saturated under the conditions of over 14$0^{\circ}C$, applied voltage and time of 4 kV/mm and 3 minutes respectively. The empirical equation for domain rotation probability, which was in proportion to square of an applied voltage and temperature and square root of time, as functions of the above parameters was defined.

• Transactions on Electrical and Electronic Materials
• /
• v.18 no.4
• /
• pp.181-184
• /
• 2017

Multilayer ceramics in which piezoelectric layers of $0.90Pb(Zr_{0.48}Ti_{0.52})O_3-0.05Pb(Mn_{1/3}Sb_{2/3})O_3-0.05Pb(Zn_{1/3}Nb_{2/3})O_3$ (0.90PZT-0.05PMS-0.05PZN) stack alternately with silver electrode layers were prepared by an advanced low-temperature co-fired ceramic (LTCC) method. The electrical properties and bonding strength of the multilayers were associated with the interface morphologies between the piezoelectric and silver-electrode layers. Usually, the inner silver electrodes are fabricated by sintering silver paste in multi-layer stacks. To improve the interface bonding strength, piezoelectric powders of 0.90PZT-0.05PMS-0.05PZN with an average particle size of $23{\mu}m$ were added to silver paste to form a gradient interface. SEM observation indicated clear interfaces in multilayer ceramics without powder addition. With the increase of piezoelectric powder addition in the silver paste, gradient interfaces were successfully obtained. The multilayer ceramics with gradient interfaces present greater bonding strength as well as excellent piezoelectric properties for 30~40 wt% of added powder. On the other hand, over addition greatly increased the resistance of the inner silver electrodes, leading to a piezoelectric behavior like that of bulk ceramics in multilayers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.253-253
• /
• 2007

압전 액츄에이터 및 초음파진동자의 응용범위가 넒어짐에 따라 변위량, 응력 등을 개선시키기 위해 전기기계결합계수 kp 및 압전 d상수가 종전보다 큰 재료가 요구되고 있으며, 초음파진동자나 압전 모터와 같이 마찰에 의한 열손실이 많이 발생하는 액츄에이터에 적용할 큰 기계적품질계수롤 가지는 저손실 압전 액츄에이터 및 초음파진동자용 재료가 필요한 실정이다. PZT계 세라믹스는 높은 유전상수와 압전특성으로 전자세라믹스분야에서 가장 널리 사용되어지고 있지만, $1200^{\circ}C$이상의 높은 소결온도 때문에 $1000^{\circ}C$ 부근에서 급격히 휘발되는 PbO로 인한 환경오염과 기본조성의 변화로 인한 압전특성의 저하가 문제시 되고 있다. $Pb(Ni_{1/3}Nb_{2/3})O_3$는 약 $-120^{\circ}C$정도의 큐리온도룰 가지는 강유전체로 Pb(Zr, Ti)$O_3$계 세라믹스에 치환 시 유전상수와 전기기계결합계수를 개선시키는 대표적인 성분이다. 따라서 본 연구에서는 저온소결 저손실의 적층형 압전 액츄에이터를 개발하기 위해 PMS-PMN-PZT계 세라믹스에 $Pb(Ni_{1/3}Nb_{2/3})O_3$ 세라믹스를 치환하고 $Li_2CO_3$와 $Na_2CO_3$ ZnO를 소결조재로 사용하여 저온소결 하였으며 PNN 치환량에 따른 결과를 관찰 하였다.

• Journal of the Korean Ceramic Society
• /
• v.36 no.10
• /
• pp.1108-1114
• /
• 1999

Microstructure and electrical properties of ZnO-doped (0-5 mol%) 0.05 Pb(Mn1/3Sb2/3)O3-0.95 PZT ceramics were investigated. Sintering temperature was decreased to 100$0^{\circ}C$ due to eutetic reaction between PbO and ZnO. Grain-size increased up to adding 1mol% ZnO and then decreased. Compositions of grain and grain-boundary were investigated by WDS. Lattice parameter was decreased with ZnO addition. Density increased with ZnO addition and reached to the maximum of 7.84(g/cm2) at 2 mol% ZnO. The effect of ZnO on electrical properties of PMS-PZT was investigated. At 3mol% ZnO addition electromechanical coupling factor(kp) was about 50% and relative dielectric constant($\varepsilon$33/$\varepsilon$0) was 997 Mechanical quality factor(Qm) decreased with ZnO addition. Lattice parameters and tetragonality(c/a) were measured to investigate relationship between the electric properties and substitution of Zn2+. At 3 mol% ZnO tetragonality was maximiged at c/a=1.0035 Curie temperature (Tc) decreased slightly with ZnO addition.