Fabrication and electrical properties of porous BS-0.64PT high temperature piezoceramics using polystyrene microsphere

摘要

Porous BiScO3-0.64PbTiO(3) (BS-0.64PT) ceramics were fabricated by using burnable plastic sphere technique (BURPS). Self-synthesized polystyrene microsphere (PS, phi 360 nm) was used as pore forming agent (PFA). Porosity of the porous ceramics was regulated by adjusting sintering temperature and volume fraction of PFA. The porous ceramics were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). All samples were pure tetragonal perovskite. Properties of the porous ceramics, including porosity, piezoelectric coefficient (d(33)) and dielectric properties (epsilon(r)) were measured. Electromechanical coupling coefficients (k(p), k(t), k(31)), mechanical quality factor (Q(m)), piezoelectric coefficient (d(31), d(h)), hydrostatic voltage coefficient (g(h)), acoustic impedance (Z), hydrostatic figure of merit (HFOM) were derived from impedance spectrum. Sintering temperature and volume fraction of PFA were optimized to bring out porous ceramics with highest g(h) and HFOM. Porous ceramic with 50 vol% PS microspheres sintered at 1000 degrees C possessed porosity of 17.12%, with g(h) and HFOM to be 0.024 V/m Pa and 6087 x 10(-15)/Pa, respectively. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.