Abstract:
PURPOSE: A lead-free piezoelectric ceramics and a manufacturing method of the same are provided to enhance the piezoelectric and dielectric property of a piezoelectric ceramics by adding (Ba0.85Ca0.15)Ti0.88Zr0.12 into a ceramics based on (K0.5Na0.5)0.95Li0.05NbO3-AgSbO3. CONSTITUTION: A lead-free piezoelectric ceramics is represented by chemical formula 1, 0.95 (K0.5Na0.5)0.95Li0.05NbO3- (0.05-x) AgSbO3-x (Ba0.85Ca0.15)Ti0.88Zr0.12O3 (0.02
Abstract:
PURPOSE: A manufacturing method of ultra-fine zirconia powder using a sedimentation process is provided to manufacture ultra-fine zirconia powder which has a regular circular shape and displays narrow size distribution by performing milling and plasticizing processes after precipitation of zirconium salt. CONSTITUTION: A manufacturing method of ultra-fine zirconia powder using sedimentation process comprises the following steps: manufacturing aqueous solution which includes water-soluble zirconium salt; performing precipitation for aqueous solution of the water-soluble zirconium salt; obtaining precipitate and manufacturing powder by performing a milling process for the precipitate; plasticizing the powder; and grinding the plasticized powder. The water-soluble zirconium salt is zirconium oxynitrate, zirconium nitrate, or zirconium oxychloride. The water-soluble solution of the water-soluble zirconium salt comprises 10-20 weight% of water-soluble zirconium salt and 80-90 weight% of water.
Abstract:
pH 조절을 이용한 FePO 4 제조 방법 및 이를 이용한 리튬이차전지 양극용 LiFePO 4 /C 제조 방법에 대하여 개시한다. 본 발명에 따른 FePO 4 제조 방법은 (a) 인산염 함유 용액에 3가 철 함유 물질을 첨가하는 단계; (b) 상기 (a) 단계의 결과 용액의 pH를 조절하여 FePO 4 를 침전시키는 단계; (c) 상기 침전된 FePO 4 를 여과하는 단계; 및 (d) 상기 여과된 FePO 4 를 건조하는 단계;를 포함하는 것을 특징으로 한다.
Abstract:
PURPOSE: BNBT piezoelectric ceramics and a method for manufacturing the same are provided to improve dielectric constant, electromechanical coupling coefficient, sintering density, mechanical quality factor, and ferroelectric stability by adding CaO and MnO to BNBT piezoelectric ceramics. CONSTITUTION: BNBT piezoelectric ceramics have a perovskite structure. The BNBT piezoelectric ceramics are made by adding CaO and MnO to (Bi0.5Na0.5) 0.94Ba0.06TiO3. The contents of the CaO and MnO are x wt% and y wt% and the x and y satisfy the inequality of 0
Abstract:
본 발명에 따른 압전재료 조성물은 (Bi 0 .5 Na 0 .5 )x Bay TiO 3 조성을 갖는 BNBT조성물; 및 상기 BNBT조성물에 첨가제인 CaO/MnO가 포함되는 것을 특징으로 한다. 또한 본 발명에 따른 압전소자는 화학식 (Bi 0 .5 Na 0 .5 )x Bay TiO3 + z(CaO+MnO)을 포함한다. 따라서 본 발명에 따른 압전재료 조성물 및 이를 이용하여 형성된 압전소자에 의하면 BNBT에 도펀트로 CaO/MnO의 함량을 조절하고 첨가하여 압전상수, 전기기계 결합계수, 상대유전상수, 기계품질요소를 포함하는 압전/유전 특성을 향상시킬 수 있는 효과가 있다.
Abstract:
High efficiency PSN-PMN-PZT piezoelectric ceramics useful for piezoelectric transformer are provided to be proper for driving strong electric-field and applied in the piezoelectric transformer by adopting Pb(Sb0.5Nb0.5)O3-PbZrO3-PbTiO3 three components system and Pb(Mn1/3Nb2/3)O3-PbZrO3-PbTiO3 three components system. The PZN-PMN-PZT piezoelectric ceramics are formed by the steps of: preparing each of PbO, ZrO2, TiO2, Nb2O5, MnCO3 and Sb2O3 powder provided that Zr/Ti ratio is 0.475/0.465; milling all of the powder by using zirconia ball and distilled water for 24 hours; drying and sizing the milled powder to particle size of less than 100mesh; calcining the sized powder at 1123K for 2 hours; grinding the calcined powder; heating and completely drying the powder under stirring, then sizing the dried powder; press molding the ground powder; and removing binder fraction from the powder through heat-sintering after molding.
Abstract:
PURPOSE: A bnbt6 piezoelectric ceramics and a manufacturing method thereof are provided to improve dielectric and piezoelectric property of the bnbt6 piezoelectric ceramic by providing the bnbt6 piezoelectric ceramics with a nano size. CONSTITUTION: Na2CO3 and Bi2O3 are preliminarily milled(S1). BaTiO3, TiO2, Na2CO3 and Bi2O3 material powder are prepared according to the composition of BNBT6 piezoelectric ceramics(S2). The material powder is mixed and milled with a ball(S3). The milled powder is calcined(S4). The calcined powder is nano-milled(S5).