Ferroic phase boundaries investigations by the acoustic emission method

By the acoustic emission, dilatometric and optic methods the phase transitions have been investigated in PbTiO 3 , PbZrO 3 and PbHfO 3 ferroelectric crystals. By the quantities of the acoustic emission activity the related coherence of the phase boundaries have been appraised. In general case the distribution on the transitions by coherence of the boundaries between the transforming phases in perovskite-type crystals are following: paraelectric-ferroelectric, paraelectric-antiferroelectric, ferroelectric-antiferroelectric, antiferroelectric-antiferroelectric. The received results have been discussed generalized in order of the similarity between the ferroelectric and martensitic phase transitions. It is shown, that acoustic emission method would be to apply for identification of the phase transition type in the multiaxial ferroic crystals fruitful.