Compositions: ceramic – Ceramic compositions – Titanate – zirconate – stannate – niobate – or tantalate or...
Patent
1990-05-21
1991-07-16
Group, Karl
Compositions: ceramic
Ceramic compositions
Titanate, zirconate, stannate, niobate, or tantalate or...
501134, 501136, 423598, 252 629, C04B 3549
Patent
active
050325590
ABSTRACT:
A procedure used to prepare Ba(Ti.sub.1-x),Zr.sub.x)O.sub.3 compositions wherein 0<x<0.25 having a more completely randomized distribution of Ti and Zr atoms on the TiO.sub.2 sublattice of barium titanate is described. In accordance with the present invention there is provided a method for preparing barium titanium zirconium oxide ferroelectic ceramic. The present method comprises mixing tetraalkyl titanate and alkyl zirconate in appropriate amounts to produce (Ti.sub.1-x Zr.sub.x)alkoxide wherein 0<x<0.25; reacting (Ti.sub.1-x Zr.sub.x) alkoxide wherein 0<x<0.25 to form (Ti.sub.1-x Zr.sub.x)O.sub.2 wherein 0<x<0.25 admixing (Ti.sub.1-x Zr.sub.x)O.sub.2 with BaCO.sub.3, said BaCO.sub.3 being added in a molar ratio greater than 1 relative to (Ti.sub.1-x Zr.sub.x)O.sub.2 ; heating the admixture for a period of time and at a temperature sufficient to produce Ba(Ti.sub.1-x Zr.sub.x)O.sub.3 wherein 0<x<0.25. The improved randomization of the Ti and Zr atom distributions results in a ferroelectric ceramic material having squarer electrical polarization hysteresis loops and higher remanent polarization values than can be obtained from conventionally prepared materials of similar composition.
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McSweeney Robert T.
Zuk Karlene
Finnegan Martha Ann
Group Karl
GTE Products Corporation
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