Study of the role of porosity on the functional properties of (Ba,Sr)TiO3 ceramics

JOURNAL OF ALLOYS AND COMPOUNDS

卷:643

Article

Stanculescu, Roxana¹  Ciomaga, Cristina E.¹  Padurariu, Leontin¹  Galizia, Pietro²  Horchidan, Nadejda¹  Capiani, Claudio²  Galassi, Carmen²  Mitoseriu, Liliana¹ 

[1] Alexandru Ioan Cuza Univ, Dept Phys, Dielect Ferroelect & Multiferro Grp, Iasi 700506, Romania

[2] CNR ISTEC, I-48018 Faenza, Italy

关键词: Ceramics;    Solid-state reactions;    Dielectric response;    Computer simulations;   

DOI  :  10.1016/j.jallcom.2015.03.252

来源: Elsevier

【 摘 要 】

The role of porosity on the low and high field dielectric properties was studied in Ba0.70Sr0.30TiO3 ceramics with various porosity levels obtained by using lamellar graphite as sacrificial template. The permittivity decreases with increasing porosity, from around epsilon similar to 7690 (dense ceramic) down to 380 (ceramic with 29% porosity), while preserving the Curie temperature at about 35 degrees C. The effective permittivity was discussed by using Effective Medium Approximation and Finite Element Method approaches. The role of porosity and specific microstructural characteristics induced by the pore forming addition, from closed porosity (0-3) towards a combined (0-3, 2-2) with lamellar-type of microstructures for the most porous ceramics was taken into consideration. All the investigated ceramics preserve a high level of tunability as in the dense material, irrespective of the porosity level, while the zero field permittivity was decreased to a few hundreds. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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