Study On Preparation And Properties Of XPb(Ni_1/3Nb_2/3)O₃-（1-x）Pb(Ti_0.6Hf_0.4)O₃Ternary Piezoelectric Ceramic

Piezoelectric ceramic is a functional material which can be mutual conversionbetween mechanical energy and electrical energy,because of its better mechanicalproperties and stability piezoelectric properties etc,it can serve as a kind ofimportant optics,heat,mechanics,electricity sensitive functional materials, widelyused in information, aerospace, electronics and other fields. With the research anddevelopment of application of piezoelectric devices, the piezoelectric ceramic highperformance and wide morphotropic phase boundary, high temperature stabilityhave caused more attention of researchers.In this paper, taking xPb(Ni_1/3Nb_2/3)O₃-（1-x）Pb(Ti_0.6Hf_0.4)O₃（hereinafterreferred to as xPNN-（1-x）PTH） piezoelectric ceramic system as the research object.Preparing nine different PNN content of PNN-PTH piezoelectric ceramics by thetechnology of the synthesis of the body after precursor, burn-in, molding pressurepiece, sintering, burn permeability silver and polarization, etc..This article can ensure the component of morphotropic phase boundary forxPNN-（1-x） PTH series in x=0.30-0.31.5through XRD diffraction pattern undernormal temperature. We have indentified the coexistent temperature range betweenrhombohedral and tetragonal phase of various components through variabletemperature XRD diffraction pattern. When x=0.25-0.28, two phase coexistenceat105-150℃; W hen x=0.29, two phase coexistence at60-105℃; W hen x=0.30-0.315, two phase coexistence at30-105℃; W hen x=0.32-0.33, there is nottwo phase coexistence. We can see sections of piezoelectic ceramic PNN-PTHthrough the SEM image. The porosity is very small, the grain boundaries is clear,particle degree is1-5μ m, having high density.This paper studies the different content of PNN piezoelectric ceramicxPNN-（1-x）PTH influence on the performance.Through the xPNN-（1-x）PTHpiezoelectric ceramic performance measurement, data analysis, the results are asfollows: xPNN-（1-x）PTH piezoelectric ceramic PNN along with the increase of thecontent of the relative dielectric constant ε₃₃/ε₀, dielectric loss tanδ, remainingpolarization strength Pr, piezoelectric constant d₃₃, electrical and mechanicalcoupling coefficient K_p,first increase maximum then decreases, which xPNN-（1-x）PTH piezoelectric ceramics have best performance at MPB: ε₃₃/ε₀=3800、tanδ=2%、Pr=35.1mC/cm²ã€d₃₃=795pC/N、K_p=0.7128. Curie temperature and PNNcontent x in a linear relationship,from x=0.25Curie temperature of225℃isbecoming smaller until x=0.33when the T_c=191℃; A long with the increase of the content of PNN x, electric field Ec decrease gradually in the x=0.25obtainedwhen9.53KV/cm and x=0.33obtained when6.18KV/cm.