Mn-MODIFIED Pb(Mg1/3Nb2/3)O3-PbTiO3 CERAMICS: IMPROVED MECHANICAL QUALITY FACTORS FOR HIGH-POWER TRANSDUCER APPLICATIONS

Authors present results concerning the development of modified Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramics with improved mechanical quality factors for high-power application. Authors have focused efforts on base PMN-PT compositions close to the morphotropic phase boundary. Evidence will be presented which indicates that the improved mechanical quality factor results from the introduction of hard characteristics into PMN-PT by the substituents. Investigations of the nonlinearity of the electromechanical properties on the vibrational amplitude were performed using a constant displacement method. The degradation of the mechanical quality factor with increasing drive amplitude also presents thermal stability problems for the usage of these materials in high-power transducer applications. 21 refs.