The properties of the non-stoichiometric ceramics (1-x)PbMg1/3Nb2/3O3-(x)PbTiO3

(1-x)PbMg1/3Nb2/3O3-(x)PbTiO3 i.e- (1-x)PMN-(x)PT ceramics with x less than or equal to0.15 have been obtained and investigated. With increasing x the temperature T-m increases, at which dielectric permittivity reaches its ma ximum (epsilon (m)), increases the value of epsilon (m) and decreases the d egree of the diffuse phase transition. For x less than or equal to0.075 dom inates electrostrictive mechanism while for x>0.075 piezo-electric effect g ives a contribution into electromechanical deformation of the samples. Spec ial attention is paid to the problem of nonstoichiometry (excess and defici t of PbO and excess of MgO). (C) 2001 Elsevier Science Ltd. All rights rese rved.