Low-temperature sintering of LiBiO2-coated Pb(Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 powders prepared by surface chemical modification method and their piezoelectric properties

Low-temperature sintering of LiBiO2-coated 0.375Pb(Mg1/3Nb2/3)O-3-0.25PbZrO(3)-0.375PbTiO(3) (PMN-PZT) powders was investigated with surface modification through the hydrolysis of lithium ethoxide and bismuth tri-t-amiloxide on the surface of PMN-PZT powders, and their microstructure and piezoelectric properties were examined. By using the surface chemical modification method, PMN-PZT powders were homogeneously coated with LiBiO2 precursor fine particles of 20-30nm. PMN-PZT bodies sintered at temperatures from 800 to 1000degreesC with a chemically added LiBiO2 sintering aid exhibited more homogeneous microstructures and improved piezoelectric proper-ties than the specimens fabricated with LiBiO2 added by a conventional mixing method. 0.75 wt% LiBiO2-added PMN-PZT ceramics fabricated at 950degreesC for 4h showed a high density of approximately 7.7 g/cm(3), and their electromechanical coupling factor (k(p)) and piezoelectric coefficient (d(33)) were 61.8% and similar to517pm/V, respectively. And also, a large field-induced strain of similar to0.17% and a well-saturated hysteresis loop with a remanent polarization (P-r) of 33.9 muC/cm(2) were observed under an applied electric field of +/-40 kv/cm.