IT 기반의 건물에너지 관리시스템

이개명,김성만,임영섭,홍주희 한국태양에너지학회 2009 태양에너지 : 한국태양에너지학회지 Vol.8 No.3

PZT 세라믹스의 전기기계결합계수 온도 안정성에 관한 연구

이개명,Lee, Gae-Myoung 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.1

In this paper, PZT piezoelectric ceramic specimens with 4 compositions (Zr/Ti=50/50, 53/47, 56/44, 58/42) in $Pb(Zr,Ti)O_3$ system were fabricated. We studied effects of poling strength and thermal aging on the temperature characteristics of eletromechanical coupling factor k31 of the specimens, which were poled with the DC electric fields, 1.5, 2.5 and 3.5 kV/mm respectively and thermally aged for an hour at $200^{\circ}C$. The eletromechanical coupling factor k31 of the specimen with the composition Zr/Ti= 53/47, nearest to the morphotropic phase boundary decreased the most greatly, irrelevant to the intensity of poling field, due to 1st thermal aging. And the temperature coefficient of eletromechanical coupling factor k31 was (-) in the tetragonal phase composition and (+) in the rhombohedral phase composition, which is reverse in the temperature coefficient of resonance frequency. It is interesting that eletromechanical coupling factor k31 of PZT ceramics is shown to be able to increase as temperature increase in the interval $-20{\sim}80^{\circ}C$.

열에이징에 의한 PZT세라믹스의 내열특성 개선

이개명,김병효,Lee, Gae-Myung,Kim, Byung-Hyo 한국전기전자재료학회 2005 전기전자재료학회논문지 Vol.18 No.1

Temperature stabilities of resonance frequencies of the substrates are very important in piezoelectric ceramics oscillators and fitters. In this study, it was investigated thermal resisting property of the length-extensional vibration mode of PZT ceramics. The mode can be utilized in fabricating ultra-small 55 kHz IF devices. We fabricated the ceramic specimens with x = 0.51, 0.52, 0.53, 0.54, and 0.55 in the Pb(Zr$\sub$x/Ti$\sub$1-x/)O$_3$ system. And their resonance frequencies were measured before 1st thermal aging, after 1st and 2nd thermal aging. In order to investigate the influence of thermal aging on thermal resisting properties, thermally aged specimens were once mote thermally aged. Before 1st thermal aging, the specimens of the compositions with morphotropic phase, x = 0.53 and rhombohedral phase, x = 0.54 have weak thermal resisting property of resonance frequency, while tetragonal phase, x = 0.51 has robust thermal resisting property of resonance frequency. 1st thermal aging improved thermal resisting property of resonance frequency in all specimens.

압전체 기판에서 에너지 포획된 두께 전단진동의 변위분포

이개명 한국전기전자재료학회 1996 電氣電子材料學會誌 Vol.9 No.9

Particle displacement distributions of the fundamental thickness shear vibration mode and overtone modes in an energy-trapped single resonator and an energy-trapped double acoustically coupled filter were calculated. The effects of the width of a pair of partial eletrodes and the magnitude of the plate back of the resonator on the particle displacement distributions of its symmetric vibration mode and anti-symmetric vibration mode were investigated. And the effects of the width of a pair of partial eletrodes, the width of the gap between two pairs of partial electrodes and the magnitude of the plate back of the filter on the particle displacement distributions of its symmetric vibration mode and anti-symmetric vibration mode were investigated.

고주파소자의 기판용 $Pb(Mn_{1/3}Nb_{2/3})O_3+PZT$ 세라믹스의 압전특성에 $Cr_2O_3$의 첨가가 미치는 영향

이개명,백동수,윤석진,홍재일,박창엽 한국전기전자재료학회 1992 電氣電子材料學會誌 Vol.5 No.1

핫프레스법으로 제작된 0.05Pb(M $n_{1}$3/N $b_{2}$3/) $O_{3}$+ 0.95Pb(Z $r_{0.47}$ $Ti_{0.53}$) $O_{3}$ 세라믹스에 있어서 C $r_{2}$ $O_{3}$의 첨가량이 그 시편의 구조적특성, 유전특성, 압전특성, 온도안정성 및 포아손비에 미치는 영향이 조사되었다. C $r_{2}$ $O_{3}$의 첨가량의 범위가 0.3~0/75[wt%]인 시편만이 포아손비가 1/3이상으로 주파수저하형 에너지포획소자의 기판으로 사용될 수 있으며 이 중에서 C $r_{2}$ $O_{3}$의 첨가량이 0.5[wt%]인 시편이 보다 우수한 압전특성과 안정된 주파수 온도특성을 갖고 있다. 있다.

고차진동을 이용하는 에너지포획형 압전 공진자와 필터의 변위분포에 관한 연구

이개명 한국전기전자재료학회 1998 전기전자재료학회논문지 Vol.11 No.11

Energy-trapped thickness vibrations of piezoelectric substrates are utilized in fabricating resonators and filters which have their operating frequencies in HF band. Normalized particle displacement distributions of the fundamental thickness shear vibration mode and overtone modes into the thickness direction in energy-trapped resonators and double-coupled filters were obtained by solving the wave equation and calculating the solved equations. These results show that as the number order of the harmonic mode in a energy-trapped resonator becomes larger, the degree of energy-trapping in the resonator increase, and if the conditions for energy-trapping become sufficiently weak, the energy-trapping effect of the harmonic mode which has the lower order disappears the earlier. Above simulation results were proved by the experiments.

압전 세라믹스 주파수 소자의 소개와 개발 동향

이개명 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.2

다른 부품 업체와 마찬가지로 이 분야에 있어서 국내 기업은 아직 시작 단계에 있으면서도 다른 선진사의 높은 기술 상태의 부품을 만들지 않으면 경쟁이 되지 않기 때문에 어려움이 많다. 또 압전 세라믹스 주파수 소자의 설계와 제작에 경험 있는 전문가도 별로 없기 때문에 시스템 업계가 요구하는 경향에 맞춰 부가가치가 높은 신 제품을 내놓기도 아직 힘든 상태이다. 통신기기와 전자기기에 있어서 이 부품의 중요성을 고려한다면 본 궤도에 도달할 때까지 외부의 지원이 필요하리라 생각된다. 아울러 전기와 재료 두 분야에 걸쳐 있는 본 압전 세라믹스 주파수 소자의 특성을 감안한다면 전기공학 전문가와 재료공학 전문가의 협력이 양산과 설계 과정에서 부딪치는 문제의 해결의 지름길이 될 수 있을 것이다.

PZT세라믹스에 있어서 길이진동모드의 온도안정성

이개명,현덕수 한국전기전자재료학회 2001 전기전자재료학회논문지 Vol.14 No.9

Temperature stabilities of dielectric constraints and resonant frequencies of the substrates are very important in piezoelectric ceramics oscillators and filters. In this study, it was investigated temperature stability of the length-extensional vibration mode of Pb(Zr$\_$y/Ti$\_$1-y/)O$_3$+x[wt%]Cr$_2$O$_3$ ceramics. The mode can be utilized in fabricating ultra-small 455 kHz IF devices. Addition of Cr$_2$O$_3$ in morphotrophic phase PZT decreased the variations of dielectric constant, electro-mechanical coupling factor k$\_$31/ and resonant frequency by thermal shock. As additive weight of Cr$_2$O$_3$increased, the temperature coefficient of resonant frequency changed from positive number to negative one. And the composition tith temperature coefficient of resonant frequency was shifted to the one with increased Cr$_2$O$_3$ additive weigh by thermal aging.

PZT 세라믹스에 있어서 길이진동모드의 경시변화

이개명,김병효,황충구,강찬호,현덕수 한국전기전자재료학회 2002 전기전자재료학회논문지 Vol.15 No.10

Aging stabilities of the operating frequency of piezoelectric devices such as filter, oscillator and discriminator are very important. In this study it was studied aging stabilities of the length-extensional vibration mode of Pb(Zr$\^$y/O$_3$+ x[wt%]Cr$_2$Co$_3$ ceramics. PZT ceramics in morphotropic phase boundary have higher aging rates of k$\_$31/ and resonance frequency than those in tetragonal phase or rhombohedral phase. Thermal aging moves the composition with maximum aging rate to Zr-rich side in Cr$_2$O$_3$ not added PZT system. In the PZT system, aging rates of k$\_$31/ and resonance frequency for first 30 days are bigger than those for the following 90 days. Thermal aging decrease those for first 30 days. Aging rate of resonance frequency of the ceramics with x=0.1, y=0.53 and x=0.3, y=0.53 increased by thermal aging.

PMN-PZT 세라믹스에 있어서 열에이징 효과

이개명 濟州大學校工科大學産業技術硏究所 1995 尖端技術硏究所論文集 Vol.6 No.-

Two types of Pb(Mn1/3Nb2/3)O₃+PZT ceramics had been fabricated by hot-pressing method. One had coarse grain and the other had fine grain due to Cr₂O₃ addition. These specimen were poled by applying the DC electric field in various steps. The effects of thermal aging on their piezoelectric characteristics and temperature stability of the frequency were investigated. The results are as follows. Change rates of piezoelectric characteristics by thermal aging in small-grain size specimens were greater than in large-grain size specimens. And only small-grain size specimens could have been better frequency temperature stability through thermal aging.