Effect of BaTi4O9 fibers on dielectric properties of 0.64BaTi4O9+0.36BaPr2Ti4O12 composites

BaTi4O9(f)/(0.64BaTi(4)O(9)-0.36BaPr(2)Ti(4)O(12)) composites are prepared for a new kind of microwave dielectric ceramics with modified dielectric constant. low dielectric loss and small temperature dependence. The phase composition, dielectric properties, the chemical state of Ti element and abundance of the constituent elements on the sample surface were characterized by X-ray diffraction (XRD), LCR meter method and X-ray photoelectron spectroscopy (XPS). The results show that this system is composed of two phases, i.e. BaTi4O9 and BaPr2Ti4O12. The content of Ti3+ and Ti2+ decrease and that of oxygen element increases in the BPT system composites due to the addition of BaTi4O9 fibers, which greatly improve the dielectric properties of this system, BPT10 sample. which has 10% BaTi4O9 fibers, has the best dielectric properties in this system (epsilon(r) = 64. tg delta = 1 x 10(-4), at 1 MHz), and might be a potential candidate for microwave dielectric ceramics. (C) 2002 Elsevier Science Ltd and Techna S.r.l. All rights reserved.