Effects of Al_2O_3 on the ferroelectric properties of sodium potassium lithium niobate lead-free piezoceramics

摘要

Aluminum oxide (A1_2O_3) has been known as a promising additive to modify the piezoelectric properties of lead-based piezoceramics. However there are few reports regarding A1_2O_3 added lead-free piezoceramics. In this study, sodium potassium lithium niobate ((Na_(o.5)K_(0.5))_(o.925)Li_(o.o75)NbO_3, NKLN) lead-free piezoelectric ceramics have been prepared and their crystal structures, microstructures ;md dielectric properties have been also investigated with different A1_2O_3 amounts and sintering temperatures. With increasing A12O_3 content up to 0.5 wt%, the density and grain size increased, accompanying with the increased dielectric and piezoelectric properties.These results could be explained in terms of sinterability such as density and grain size.