Sk. Mishra et al., EFFECT OF PHASE COEXISTENCE AT MORPHOTROPIC PHASE-BOUNDARY ON THE PROPERTIES OF PB(ZRXTI1-X)O-3 CERAMICS, Applied physics letters, 69(12), 1996, pp. 1707-1709
The temperature variation of planar electromechanical coupling coeffic
ient (k(p)) in Pb(ZrxTi1-x)O-3(PZT) ceramics near the morphotropic pha
se boundary (MPB) compositions has been correlated with structural cha
nges to show that the maximum electromechanical response at a given co
mposition (x) is a function of temperature (T) and occurs in the tetra
gonal phase field just outside the two-phase MPB region in the (x,T) p
lane. This clearly disproves the hypothesis that the coexistence of rh
ombohedral and tetragonal phases at MPB is responsible for the enhance
ment of the electromechanical response. In fact, coexistence of the rh
ombohedral phase with the tetragonal phase is shown to lead to the low
ering of the electromechanical response. (C) 1996 American Institute o
f Physics.