DIELECTRIC-CONSTANTS OF PMN-PYROCHLORE MIXTURE AND POROUS PZT CERAMICS

A new model for diphasic composite changing its connectivity from 3-0 to 0-3 via 3-3 are proposed here, which combined 3-0 (0-3) and 3-3 mod els. Dielectric constant of the composite and dielectric, elastic and piezoelectric constants of porous PZT ceramics are derived as a functi on of volume fraction of phase 1 and porosity based on the model, resp ectively. These results were compared with previous obtained experimen tal data on Pb(Mg-1/3 Nb-2/3)O-3-pyrochlore phase mixture and highly p orous PZT ceramics. Assuming that the diphasic composite changes its c onnectivity from 3-0 to 0-3 via 3-3, a good agreement between experime ntal and theoretical results is observed.