Modification of mechanical properties in PMNT 90 : 10 by substitution withLa

Modern actuator systems require highly specialised, tailored electroceramic compositions, in order to realise their full potential. These modification s include many mechanical modifications, such as density adjustment, transp arency, and grain size refinement. The work reported here describes a very simple method by which the Young's modulus in the system Pb(Mg1/3Nb2/3)O-3 can be accurately controlled, by substitution with low La concentrations on to the Pb site; substitution of 1 at% La raises the Young's modulus from 98 .6 to 116 MPa in the composition Pb(Mg1/3Nb2/3)(0.9)Ti0.1O3. This may be us ed to raise significantly the resonant frequency of an actuating system. La doping was also shown to increase the porosity, from 0.4 to 2.8%. (C) 2000 Elsevier Science Ltd. All rights reserved.