The hot isostatic pressing (HIP) is used in this work as a post-sintering t
reatment to obtain piezoelectric ceramics with very low contents of porosit
y. The method is applied to calcium modified lead titanate ceramics with a
wide range of microstructures, corresponding to successive sintering stages
. The effects of HIP on the various cases are quantitatively determined, ch
ecking the effectiveness of the treatment to reduce the porosity without fu
rther grain growth. A combination of computer-aided image processing and me
asurement with optical and scanning electron (SEM) micrographs and transmis
sion electron microscopy (TEM) are used to characterise the microstructures
. The effect of HIP on the porosity is different depending on the sintering
stage of the ceramic. Their ferropiezoelectric behaviour is also evaluated
in relation to the microstructural changes. (C) 2000 Elsevier Science Ltd.
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