The hot high distortion piezoelectric PLZT ceramics which tantalum and niobium is doped

摘要

(57) Abstract It is produced general system (Pb_{1-xLa x}) (Zr _yTi1-y) _{1- (x/4) - the} PLZT piezoelectric ceramics which possesses _zM^a+4z/aO3 2.0 - 3.0% Nb⁵⁺ (the mol %) and 2.0 - 3.0%Ta5+ (the mol %) as the dopant Nb₂ O PbO and TiO_{2 which} possess_{5 which} is added in order to make form and Ta₂ O₅, ZrO by the hot forging process which uses the powder of₂, and La₂ O₃. ZrO the powder of₂ and TiO₂ y/(1-y) is mixed at mol ratio, this desirable mol ratio is, 55/45 calcination is done with approximately 1300C, - the 1500C is pulverized with the ball mill in acetone, evaporates and becomes the dry powder. Next, this ZrO the blend of₂ and TiO₂ is connected PbO and La₂ O₃, Nb₂ O the powder of₅, and Ta₂ O₅, and this new blend is pulverized with the ball mill in acetone, evaporates to the dry powder, calcination is done with approximately 700C, - the 850C and the sieve is and is done to divide, the grain size of approximately 0.5 - 1.5 millimicrons obtains. The last PLZT powder which this Nb/Ta is doped forms in desire form by normal temperature compression, continuously in oxygen is sinterred with approximately 1000C - the 1150C. This PLZT ceramic substance furthermore to high density is converted up to approximately 98.5% of theoretical maximum density of the aforementioned substance by heating to approximately 1175C - the 1275C with the uniaxial compression 300 - 1200psi. The distortion hysteresis where the PLZT piezoelectric ceramics which Nb/Ta of the hot high performance which is obtained is doped average grain size of approximately 3 millimicrons, the clear polarization hysteresis loop, is due to the impression of unipolar electric field and decreases, the insulated breaking strength which is larger than 25kV/cm, the linear piezoelectric factor of approximately 790pC/N (d₃₃), maximum it is larger than 0.16% it is warped, at least fatigue life of 108 cycle, and approximately shows Tc of 205 - the 208C.