• 제목/요약/키워드: PbO2

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용융(熔融) PbO-SiO2계(系) 슬래그와 Bi 사이의 Bi와 Pb의 분배거동(分配擧動) (Distribution Behavior of Bi and Pb Between Molten PbO-SiO2 Slag and Bi)

  • 김세종;김응진;손호상
    • 자원리싸이클링
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    • 제21권5호
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    • pp.65-71
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    • 2012
  • 용융 PbO-$SiO_2$계 슬래그와 Bi를 $775{\sim}850^{\circ}C$의 마그네시아 도가니 중에서 평형시켜 Pb와 Bi의 평형분배에 대하여 조사하였다. 분위기 중의 산소분압은 $P_{CO2}/P_{CO}$의 비율을 조정하여 제어하였다. Pb의 분배비인 (%PbO)/[%Pb]는 슬래그 중의 $SiO_2$ 농도가 증가함에 따라 증가하였으며, Bi의 분배비인 ($%Bi_2O_3$)/[%Bi]는 슬래그 중의 $SiO_2$ 농도가 증가함에 따라 감소하였다. 그리고 반응 온도가 높을수록 금속 상중의 Pb 농도는 증가하였다. 이러한 결과는 열역학적으로 예측한 결과와 잘 일치하였다.

초전센서 응용을 위한 $Pb(Mg_{1/3}Nb_{2/3}O_3-PbTiO_3$ 세라믹계 초전특성 (Pyroelectric property of $Pb(Mg_{1/3}Nb_{2/3}O_3-PbTiO_3$ ceramics for pyroelectric sensor application)

  • 황학인;정종만;박준식
    • 한국결정성장학회지
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    • 제8권4호
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    • pp.667-672
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    • 1998
  • Columbite precursor 방법을 이용하여 제조한 Pb(Mg1/3Nb2/3)O3-PbTiO3 세라믹계의 초전특성을 $1000^{\circ}C$에서 $1250^{\circ}C$의 소결온도 범위에서 관찰하였다. Pb(Mg1/3Nb2/3)O3-PbTiO3 계는 전형적인 완화형 강유전특성을 나타내었다. $1250^{\circ}C$에서 2시간 소결한 $Pb(Mg_{1/3}Nb_{2/3})O_3-PbTiO_3$ 세라믹의 경우, 높은 소결밀도와 향상된 초전특성을 얻을수 있었다. $Pb(Mg_{1/3}Nb_{2/3})O_3-PbTiO_3$세라믹은 항온장치를 이용할 경우 초전 센서로의 응용가능성을 나타내었다.

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PbO 과잉량이 Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3계의 소결 및 압전특성에 미치는 영향 (Effect of Excess PbO Addition on Sintering and Piezoelectric Characteristics in Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3 System)

  • 전구락;김정주;조상희;김도연
    • 한국세라믹학회지
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    • 제26권4호
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    • pp.568-574
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    • 1989
  • Effect of PbO addition on sintering and piezoelectric properties at 0.45Pb(Ni1/3Nb2/3)O3-0.40PbTiO3-0.15PbZrO3 composition which is tetragonal phase was investigated. In this composition, Porosity and dielectric constant were increased with excess PbO addition, but Kp and d31 was not changed. These variation of physical properties could be interpreted as composition change of solid grains from tetragonal to MPB region due to amount of PbO-rich liquid changing.

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Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3계의 삼방정, 정방정 및 상경계조성에서의 MnO2 첨가에 따른 유전 및 압전특성에 비교 (Comparisons on Dielectric and Peizoelectric Proeprties of Rhombohedral, Tetragonal and Morphotropic Phase Boundary in Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3 System with MnO2 Addition)

  • 전구락;손정호;김정주;조상희
    • 한국세라믹학회지
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    • 제25권5호
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    • pp.488-494
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    • 1988
  • Effects of MnO2 addition on themicrostructure, dielectric and piezoelectric properties of Rhombohedral, Tetragonal and Morphotropic phase boundary(MPB) in Pb(Ni1/3Nb2/3)O3-PbTiO3-PbZrO3 system were investigated and respectively the amount of MnO2 addition was 0, 0.2, 0.5, 1.0, 3.0wt%. In the tetragonal region, compared with the Rhombohedral and Morpotropic phase boundary, Mechanical quality factor(Qm), Curie temperature(Tc) and Dissipation factor were promoted by addition of MnO2. According to the results of the microstructure, dielectric and piezoelectric properties, the solid solution range of MnO2 addition in this system was 0.2-0.5wt%.

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Effects of Additives on the Properties of $YBa_2Cu_3O_x$

  • Soh, Dea-Wha;Cho, Yong-Joon;Fan, Zhanguo
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.341-344
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    • 2004
  • The superconducting properties of $YBa_2Cu_3O_x$ with different content impurities of PbO and $BaPbO_3$ were studied. When the PbO was used as an additive in $YBa_2Cu_3O_x$, although the melting point could be reduced, the superconductivity became poor. From the XRD pattern of the sintered mixture of $YBa_2Cu_3O_x$ and PbO it was known that there is a reaction between $YBa_2Cu_3O_x$ and PbO, and the product is $BaPbO_3$. In the process of the reaction the superconducting phase of $YBa_2Cu_3O_x$ was decreased and $BaPbO_3$ would be the main phase in the sample. Therefore, $BaPbO_3$ was chosen as the impurity additive for the comparative study. The single phase of $BaPbO_3$ was synthesized by the simple way from both mixtures of $BaCO_3$ and PbO, $BaCO_3$ and $PbO_2$. Different contents of $BaPbO_3$ (10%, 20%, 30%) were added in the $YBa_2Cu_3O_x$. By the Phase analysis in the XRD patterns it was proved that there was no reaction between $YBa_2Cu_3O_x$ and $BaPbO_3$. When $BaPbO_3$ was used as impurity in $YBa_2Cu_3O_x$ the superconductivity was much better than PbO as an impurity additive in $YBa_2Cu_3O_x$.

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$Nd^{3+}$로 치환된 $Pb(Mg^{1/3}Nb^{2/3})O_3$$PbTiO_3$ 첨가에 따른 유전특성과 PbO 휘발 (Effects of $PbTiO_3$ Addition on Dielectric Properties and Extent of PbO Loss in Nd-Doped $Pb(Mg^{1/3}Nb^{2/3})O_3$ System)

  • 김성열;이응상
    • 한국세라믹학회지
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    • 제30권8호
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    • pp.671-677
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    • 1993
  • Effects of PbTiO3 addition on dielectric properties and extent of PbO loss in Nd-doped Pb(Mg1/3Nb2/3)O3 system were investigated. As the proportion of dopping increased, the phase transition temperature shifted to low region, and the dielectric constant at room temperature decreased rapidly. But as the proportion of PbTiO3 increased, the phase transition temperature shifted to high retion, and the dielectric constant at room temperature increased. The substitution of Nd3+ for Pb2+ decreased the amount of PbO evaporation, therefore the sample sintered well in case of only 1 mole% adding excess PbO.

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$Pb(Mg_{1/3}Nb_{2/3})O_3$계 세라믹스의 $Pb^{2+}$$Nd^{3+}$로 치환함에 따른 유전특성 및 PbO 휘발에 관한 연구 (Influence on Dielectric Properties and Evaporation of PbO According to Substituting $Nd^{3+}$ for $Pb^{2+}$ in $Pb(Mg_{1/3}Nb_{2/3})O_3$ System)

  • 김성열;이응상
    • 한국세라믹학회지
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    • 제30권3호
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    • pp.175-180
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    • 1993
  • Influence of Nd3+ substitution for Pb2+ on the dielectric properties and the PbO evaporation according to substituting Nd3+ for Pb2+ in Pb(Mg1/3Nb2/3)O3 system ceramics have been investigated. The dielectric constant at the curie temperature and evaporation of PbO were decreased with increase of Nd3+ amounts. The percentage of PbO evaporation was 2.5wt% in the PMN system substituted Nd3+ for Pb2+, while it was 3.7wt% in the PMN system.

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$Fe_2O_3$ 첨가에 따른 $Pb(Y_{1/2}Ta_{1/2})O_3-PbZrO_3-PbTiO_3$ 세라믹스의 전기적 특성 (Electrical Properties of $Pb(Y_{1/2}Ta_{1/2})O_3-PbZrO_3-PbTiO_3$ Ceramic s as a function of $Fe_2O_3$content)

  • 강도원;김태열;김범진;박태곤;김명호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.297-299
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    • 1999
  • Effects of additives on the ceramic and electrical properties of Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$ceramics in a perovskite type structure were investigated. The dielectric and piezoelectric properties of the base composition were improved markedly through selection of Fe$_2$O$_3$ additives in proper amounts. The composition Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$ obtained the dielectric constant ($\varepsilon$$_{r}$=1,425). Also, electromechanical couping factors for planar(k$_{p}$) and piezoelectric constant(d$_{33}$) were obtained 0.50 and 294[pC/N] at the additives 0wt% Fe$_2$O$_3$ respectively. The mechanical quality facor(Q$_{m}$) of Pb(Y$_{1}$2/Ta$_{1}$2/)O$_3$-PbZrO$_3$-PbTiO$_3$+Fe$_2$O$_3$(0.3 wt%) is about 510.510.510.

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다층 구조로부터 열 확산에 의한 $PbTiO_3$ 박막의 제조 (Formation of $PbTiO_3$ Thin Films by Thermal Diffusion from Multilayrs)

  • 서도원;최덕균
    • 한국세라믹학회지
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    • 제30권6호
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    • pp.510-516
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    • 1993
  • $PbTiO_3$ thin films have been formed by rapid thermal annealing(RTA) of $TiO_2$/Pb/$TiO_2$ multilayer films deposited on Si wafers by RF sputtering. Based on the optimal depositon conditions of TiO2 and Pb, $TiO_2$/Pb/$TiO_2$ three layers were deposited for 900$\AA$ each. These films were subjected to RTA process at the temperatures ranging from $400^{\circ}C$ to $900^{\circ}C$ for 30 seconds in air, and were analyzed by X-ray diffraction and transmission electron microscopy to investigate the phases and the microstructures. As a result, perovskite $PbTiO_3$ phases was obtained above $500^{\circ}C$ with the trace of unreacted $TiO_2$. RBS analysis revealed the anisotropic behavior of diffusion that the diffusivity of Pb to the bottom $TiO_2$ layer was faster than that of Pb to the top $TiO_2$ layer. The amorphous Pb-silicate was formed between film and Si substrate due to the diffusion of Pb, but Pb-silicate existed locally at the interface and the amount of that phase was very small. Therefore the effect of bottom $TiO_2$ layer as a diffusion barrier was confirmed. $PbTiO_3$ films formed by current technique showed a relative dielectric constant of 60, and the maximum breakdown field reached 170kV/cm.

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