Article ID Journal Published Year Pages File Type
5438908 Ceramics International 2017 6 Pages PDF
Abstract
Sr0.30Ba0.70Nb2O6 (SBN30) ferroelectric ceramics were fabricated by conventional sintering (CS) and by hot-pressing sintering (HP) and their crystal structure, microstructure, dielectric, ferroelectric and pyroelectric properties were studied and compared. Preferred orientation of the HP ceramics was detected through X-ray diffraction. Dense microstructure virtually free of pores has been achieved in HP samples. Moreover, the HP samples manifested prominent anisotropy in electrical properties. Besides, the relative permittivity (εr), saturated polarization (Ps), pyroelectric coefficient (p) in the direction perpendicular to the pressing axis were much higher than those of the randomly oriented CS samples. The HP samples sintered under 200 MPa show excellent pyroelectric properties in the direction perpendicular to the pressing axis, with pyroelectric coefficient of 2.38×10−8C/cm2K and pyroelectric figure of merit of Fi=1.13 pm/V, Fv=1.89 m2/C and Fd=0.63 μPa−1/2,which roughly triple the values obtained in CS samples. These results indicate that hot-pressing is a viable option for accessing single-crystal-like anisotropy as well as enhanced electrical properties in polycrystalline ceramics, thus unveiling the distinctive potential of HP SBN30 ceramics for infrared detector applications.
Keywords
Related Topics
Physical Sciences and Engineering Materials Science Ceramics and Composites
Authors
, , , , , ,