Development of high performance donor doped pmn pin pt piezoceramics for transducer applications

Abstract

This thesis is focused on the lead based relaxor ferroelectric materials with suitable donor doping at the A-site by conventional solid-state sintering method and their characterization studies. Chapter 1 presents the concise introduction of ceramics, perovskite structure, dielectric property, ferroelectricity, piezoelectricity, relaxor ferroelectrics, energy storage properties and applications. The scope and outline of thesis was also described. Chapter 2 provides an explanation of the experimental method used to synthesize ceramic powders (solid-state reaction method) and characterization studies for piezoelectric ceramics that are also presented in this work. Chapter 3 presents the synthesis of pure 42Pb(Mg0.335Nb0.665)O3 24Pb(In0.5Nb0.5)O3 34PbTiO3 (PMINT 42/24/34) and x mol % Sm2O3-doped PIMNT 42/24/34 (x = 1, 2 and 3) piezoceramics by conventional solid-state sintering technique. The X-ray diffraction studies reveal that all solid solutions having pure perovskite structure close to the morphotropic phase boundary (MPB) at room temperature with tetragonal phase as the dominant phase. The ferroelectric Curie temperature (Tc) demonstrates strong dependence on dopant concentration and exhibits a maximum value for pure PIMNT 42/24/34 sample. The Sm3+ entered into A-site of PIMNT 42/24/34 system and induced relaxor behaviour. newline