| As a piezoelectric ceramics with excellent piezoelectric properties, lead zirconate titanate(PZT) has been used in aviation, aerospace and other fields, such as aircraft engine piezoelectric igniter, etc. However, in the process of actual use, the piezoelectric properties of the piezoelectric components can not meet the demands to a certain extent. piezoelectric aging result in the crack of the sample in the process of using. The purpose of this article is to enhance the piezoelectric properties of the PZT piezoelectric ceramics, and improve the aging performance.In addition, as a kind of transparent photoelectric functional ceramics, lead lanthanum zirconate titanate(PLZT) has both ferroelectric, piezoelectric and excellent photostriction, which can realize the integration of light energy-electrical energy-mechanical energy, having important application prospect in the field of optical spinner, planetary exploration, etc. PLZT the preparation of transparent ceramics was strain performance research of exploration and performance to become extremely important. It is extremely important to explore the preparation of PLZT transparent ceramics and study its photostriction.PZT with a composition of Pb1.05(Zr0.52Ti0.48)O3, which is near the morphotropic phase boundyar(MPB) was selected in the study. This article explore the preparation high density of PZT piezoelectric ceramics, including powder preparation, sample molding and sintering process. PZT powder preparated by co-precipitation, its best presintering temperature was determined as 700 ℃ by X-ray diffraction(XRD). Through the study the influence of PVA content and evacuation process to sample density, the optimum molding process is: the PVA content is 5wt%, rising at the rate of 1℃/min to 300℃, and then slowly rising at the rate of 0.5℃/min to 500℃, heat preservation with 500℃ 1h then furnace cooling. It mainly discussed the sintering temperature, holding time, the embedding powder, sintering methods to the influence of sample density and performance, and finally determined the best sintering technology of PZT ceramics: oxygen atmosphere sintering method, sample covered by PZT powders with Zr O2 following for the embedding method, the condition of 1150℃ heat holding 2 h. Finally, the sample got the best comprehensive performance: density is 98.65%, εr= 2019, tanδ= 1.48%, d33 = 434 p C/N, Pr = 22.49 μC /cm2.According to the problem of PZT piezoelectric ceramics aging problem, this paper select PZT as base, Sr2+, Ba2+ for A doping, Nb5+ for B doping, enhance the piezoelectric properties of PZT ceramics, improve the aging performance, and explore the law of aging. Results shows that: with the increase of Sr2+ doping amount, MPB gradually move to the tetragonal, when doping content is 5wt%, get the best comprehensive performance: εr= 1609, tanδ= 1.84%, d33 = 440.8 p C/N, Pr = 16.5μC /cm2, Ec = 34.9 k V/cm. With the increase of Ba2+ doping amount, MPB gradually move to the rhombohedral, when doping content is 6wt%, get the best comprehensive performance: εr= 1536, tanδ= 2.01%, d33 = 465.9 p C/N, Pr = 17.5μC /cm2, Ec = 36.2 k V/cm. The aging law of PZT ceramic piezoelectric constant as follows: 10 days straight aging law, 11 to 60 days natural logarithm aging law, asymptotically linear aging law 61-120 days.According to the problem of preraration of PLZT transparent ceramic, this paper mainly explore two aspects of powder preparation and sintering process. It determined the sol-gel method is the best preparation technology of PLZT powder by X-ray diffraction(XRD), particle size, powder dispersion analysis. Sintering in O2 atmosphere, SPS sintering were used respectively to the fabrication of PLZT ceramics. Sintering in O2 atmosphere PLZT sample density was 97.8%, opaque, its comprehensive performance: εr= 1623, tanδ= 1.21%, d33 = 460.8 p C/N, Pr = 25.13μC /cm2, Ec = 37.24 k V/cm. SPS sintering sample density was 99.5%, and the sample was transparent, its comprehensive performance: εr= 1813, tanδ= 0.85%, d33 = 476.6 p C/N, Pr = 34.72μC /cm2, Ec = 32.16 k V/cm. In the same light intensity, by comparative studying the photostriction of the polarized direction and the non-polarized direction, found that: the photostriction of polarization direction is greater than the polarization direction. In the same light intensity, results showed that the photostriction of SPS sintering PLZT samples is almost 1.4 times bigger than the photostriction of atmosphere sintering PLZT samples. |
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