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The paper tries to prepare dense piezoceramics by way of
reactive liquid phase sintering. Technique concerning a low-
temperature sinterable process is developed by incorporating
4PbO.B2O3. The host system included three perovskite type
piezoceramics. The 4PbO.B2O3 have a low flow temperature and
high polarizability which was elpful to the dielectric and
piezoelectric properties of the system. If small amount of
4PbO.B2O3 glass powder was added to the calcined host
system, the liquid phase which would increase surface diffusion
and enhance the grain growth during sintering. Hence, the
sintering temperature can be reduced and the piezoelectric
and dielectric properties were improved. By the way of the
variation of the fabrication process, the influence of
sintering and poling conditions on the properties of the
ceramics was studied. Grain growth in ceramics with
sintering time, as well as sintering temperature and amounts
of 4PbO.B2O3 dopants, was also studied. In Ba(Ti,Zr)O3, grain
growth has a peculiar phenomena. The initial liquid has a high
curvature which aids solubility and penetration. As a
consequence, the spreading liquid can penetrate the solid-solid
interfaces. Penetration leads to disintegration of the solid
and subsequent rearrangement of fragments. The grain growth was
analyzed from the kinetic grain growth equation.
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