EFFECTS OF PRESSURE, DC-ELECTRIC FIELD AND FREQUENCY ON THE DIELECTRIC-PROPERTIES OF LEAD INDIUM NIOBATE

The pressure (0-6kbar), DC-bias field(0-11kV/cm) and frequency (300Hz-100kHz) dependence of dielectric properties of PIN ceramics prepared by different thermal processing techniques (conventional method;sample A and fast firing; sample B) were reported. PIN sample A reveals coexistence of a ferroelectric relaxor (disordered state) and antiferroelectric phase (ordered one), while sample B reveals a ferroelectric relaxor. For sample A, the permittivity maximum (epsilon rm' =1800 at 1kHz) temperature Tm decreases with pressure (dTm/dp=-2-degrees-C/kbar and antiferroelectric transition temperature Tt increases with p(dTt/dp=5-degrees-C/kbar). For sample B (with epsilon rm' =3500 at 1kHz), the Tm decreases with dTm/dp=-3-degrees-C kbar and a remarkable decrease in epsilon rm' with DC-bias field and a strong dielectric relaxation of polydispersive type which obeys the Cole-Cole arc law were observed.