Effect of Pore Shape on the Electrical Property of Porous LNKN Piezoceramics

Porous Li 0.06 (Na 0.5 K 0.5 ) 0.94 NbO 3 (LNKN-6) piezoceramics with different pore shapes and volumes have been fabricated by sintering a mixture of calcinated LNKN-6 powder and volatilizable pore formers of phenol resin fibers (Kynol™) or plastic spheres [poly(methyl methacrylate)] (PMMA). Kynol™ fiber was shown to more effective for inducing open-pore formation in the ceramics than PMMA sphere. The porous LNKN-6 ceramics prepared using Kynol™ fiber demonstrated lower dielectric loss, higher piezoelectric constant (d 33 ), and higher piezoelectric voltage coefficient (g 33 ) than those prepared using PMMA sphere. The effect of pore shape on the electrical property was investigated.