2013/11/16 by Rishikesh Pandey, Ashish Tiwari, Ashutosh Upadhyay +1
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Dielectric #Ferroelectric and Piezoelectric Materials #Ferroelectricity #Materials science #Microwave Dielectric Ceramics Synthesis #Multiferroics and related materials #Phase (matter) #Phase boundary #Phase transition #Physics #Rietveld refinement #Tetragonal crystal system #cond-mat.mtrl-sci
paper · pdf · doi:10.1016/j.actamat.2014.05.023
published as Acta Materialia 76, 198 (2014) · 22 pages, 13 figures, manuscript submitted in Acta Materialia and under consideration from 12/06/2013
arxiv created 2013/11/16 · openalex publication_date 2014/06/12 · arxiv updated 2014/06/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Structure of the morphotropic phase and the phase coexistence region has been investigated in (1-x)Bi(Mg1/2Zr1/2)O3-xPbTiO3 ceramics. The structure is cubic with space group Pm3m for the compositions with x<0.57 and tetragonal with space group P4mm for the compositions with x>0.59. For the compositions with 0.56<x<0.60, both the tetragonal and cubic phases coexist, which suggest very narrow morphotropic phase boundary region of compositional width Δx~0.03. Rietveld refinement of the structure using x-ray diffraction data confirms coexistence of the tetragonal and cubic phases in the MPB region and rules out the coexistence of tetragonal and rhombohedral structure reported by earlier workers. After poling appearance of significant value of electromechanical coupling coefficient in the cubic compositions (x=0.55, 0.56) suggests the presence of electric field induced transition from centrosymmetric cubic phase to noncentrosymmetric phase. Polarization- Electric field hysteresis loop measurement on the cubic composition with x=0.56 gives well saturated loop similar to that observed in Pb(Mg1/3Nb2/3)O3 relaxor below the freezing temperature.