Structural phase transformation and electrical properties of (0.90–x)Pb(Mg1/3Nb2/3)O3–xPbTiO3–0.10Pb(Fe1/2Nb1/2)O3 ferroelectric ceramics near the morphotropic phase boundary

Abstract Novel solid solutions of (0.90 – x )Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 –0.10Pb(Fe 1/2 Nb 1/2 )O 3 , where x = 0.29, 0.31, 0.33 and 0.35, were investigated from the viewpoint of structural phase transformation, dielectric, ferroelectric and piezoelectric properties. X-ray diffraction and Raman scattering measurements demonstrated that their phase structures experienced a gradual transition process from rhombohedral to tetragonal phase near the morphotropic phase boundary (MPB) region with increasing PbTiO 3 content ( x ). Corresponding to the structural phase transition near the MPB, large dielectric constants (e r ) were obtained at the compositions of x = 0.31 (e r = 3094 at 1 kHz) and x = 0.33 (e r = 2927 at 1 kHz). The maximum remnant polarization ( P r = 26.5 μC cm −2 ) was obtained at the composition x = 0.31, and the electromechanical factor ( k p = 0.59) and piezoelectric coefficient ( d 33 = 545 pC N −1 ) were also maximized at this composition, which indicated the enhanced electrical properties near the MPB.