http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이동현,이승환,이성갑,이규탁,이영희,Lee, Dong-Hyun,Lee, Seung-Hwan,Lee, Sung-Gap,Lee, Ku-Tak,Lee, Young-Hie 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.7
We studied sintering temperature to enhance the piezoelectric properties of $0.98(Na_{0.5}K_{0.5})NbO_3-0.02Li(Sb_{0.17}Ta_{0.83})O_3$+0.01wt%ZnO (hereafter NKN-LST+ZnO) lead free piezoelectric ceramics. The synthesis and sintering method were the conventional solid state reaction method and sintering was executed at $1,080\sim1,120^{\circ}C$. We found that NKN-LST+ZnO ceramics at optimal sintering temperature showed the improved piezoelectric properties at the optimal sintering temperature. The NKN-LST+ZnO ceramics show good performance with piezoelectric constant $d_{33}$= 153 pC/N sintered at $1,090^{\circ}C$. The results reveal that NKN-LST+ZnO ceramics are promising candidate materials for lead-free piezoelectric application.
MnO₂ 첨가량에 따른 비납계 (Na,K,Li)(Nb,Sb,Ta)O₃ 세라믹스의 전기적특성
이승환(Seung-Hwan Lee),남성필(Sung-Pill Nam),이동현(Dong-Hyun Lee),이성갑(Sung-Gap Lee),이상철(Sang-Chul Lee),이영희(Young-Hie Lee) 대한전기학회 2011 전기학회논문지 Vol.60 No.4
Electrical properties and microstructure were investigated on the effects of MnO₂ and the lead-free (Na0.44K0.52Li0.04)(Nb0.83Sb0.07Ta0.1)O₃ ceramics with the addition of MnO₂ were fabricated by a conventional mixed oxide method. A gradual change in the crystal and microstructure was observed with the increase of MnO₂ addition. For the NKN-LST-xmol%MnO₂ sintered at 1100℃, bulk density increased with the addition of MnO₂ and showed maximum value at addition 1.0mol% of MnO₂. Curie temperature of the NKN-LST ceramics slightly decreased with adding MnO₂. The dielectric constant, piezoelectric constant (d₃₃) and electromechanical coupling factor (kp) increased below 0.25mol% of MnO₂ addition, which might be due to the increase in density. The high piezoelectric properties = 145 pC/N, electromechanical coupling factor = 0.421 and dielectric constant = 2883 were obtained for the NKN-LST-0.25mol%MnO₂ sintered at 1100℃ for 4h.
Yb<sub>2</sub>O<sub>3</sub>가 첨가된 (Ba<sub>1</sub>Sr<sub>1</sub>Ca)TiO<sub>3</sub>후막의 치밀화와 유전특성
박상만,이영희,남성필,이성갑,Park, Sang-Man,Lee, Young-Hie,Nam, Sung-Pil,Lee, Sung-Gap 한국전기전자재료학회 2007 전기전자재료학회논문지 Vol.20 No.7
[ $(Ba_{0.57}Sr_{0.33}Ca_{0.10})TiO_3$ ] (BSCT) powders, prepared by sol-gel method, were mixed with organic vehicle and the BSCT thick films were fabricated by the screen printing method. The structural and dielectric properties were investigated as a function of the $Yb_2O_3$ doping contents. As a result of the TG-DTA, exothermic peak was observed at around $670^{\circ}C$ due to the formation of the polycrystalline perovskite phase. All BSCT thick films showed the typical XRD patterns of a cubic polycrystalline structure. The average thickness of all BSCT thick films was about $70{\mu}m$. The grain size of the BSCT thick film doped with 0.7 mol% $Yb_2O_3$ was approximately $6.2{\mu}m$. The Curie temperature and relative dielectric constant at room temperature decreased with increasing $Yb_2O_3$ amount. Relative dielectric constant and dielectric loss of the specimen doped with 0.1 mol% $Yb_2O_3$ were 4637 and 19 % at Curie temperature, respectively.