Fabrication And Characterization Of3-1Type Porous Lead Zirconate Titanate Ceramic

Porous lead zirconate titanate (PZT) ceramic is a kind of important piezoelectric composite material. Air is introduced into the phase to overcome the low sensitivity and poor acoustic impedance matching of dense PZT ceramic, which makes it widely used in underwater acoustic transducer fields. In this paper,3-1type porous PZT ceramics with highly ordered and unidirectional oriented pores in the micrometer was fabricated by the alginate gel method (self-diffusion method) and provides new ideas and methods for the preparation of porous PZT ceramics.3-1type porous PZT ceramic fabricated in this experiment are superior to other preparation methods for the through-hole structure. Porous PZT ceramics obtained in this work has a typical honeycomb structure, with a porosity as high as64.8%, HFOM as high as8917x10-5Pa-1, which was100times more than the dense PZT ceramic, the lowest acoustic impedance reached1.95MRayls, very closely to the acoustic impedance of water (1.5MRayls) and biological tissue(1-2MRayls).Studies have shown that, CaO content has a great influence on the electrical properties of porous PZT ceramic. When added a small amount of CaO, the vickers hardness of the porous PZT ceramic can be effectively improved, thereby enhancing its mechanical properties. The increasing of sintering temperature improved the growth of grains and reduced the air phase with no piezoelectric activity, thus enhanced the piezoelectirc coefficient of porous PZT ceramic, but the increase of the relative permittivity was more significantly, thereby the increasing of sintering temperature was not conductive to the improvement of the electrical properties of the PZT ceramic. To conclude,1150℃was the optimum sintering temperature of all the samples.In this paper, the cross-linking reaction rate was analyzed. The increase of solid loading and sodium alginate content improved the viscosity of the slurry, which hindered the diffusion of Ca2+.Cross-linking temperature played an important impact on the cross-linking rate for the sensitivity of sodium alginate to temperature. In our study, the porous PZT ceramic possessed the best pore morphology when the solid loading was5-15wt%, the concentration of sodium alginate was2wt%and the diffusion temperature was20℃.In addition, we studied the effects of various parameters on the microstructure and electrical properties of porous PZT ceramic and proved that the fabrication method of sodium alginate gel is a feasibility method of porous PZT ceramic. The porous PZT ceramic prepared by this method possessed a3-1interconnected pore structure and high hydrostatic figure of merit.