Microstructure and impedance spectroscopy of 3YTZP/SWNT ceramic nanocomposites. Issue 10 (December 2015)

• Record Type: Journal Article
• Authors: Poyato, R.; Macías-Delgado, J.; Gallardo-López, A.; Muñoz, A.; Domínguez-Rodríguez, A.
• Is Part Of: Ceramics international. Volume 41:Issue 10(2015)Part A
• Page Start: 12861
• Page End: 12868
• Publication Date: 2015-12
• Subjects: B. Composites -- Carbon nanotubes -- Processing -- Impedance Spectroscopy; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.06.123
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: This work provides new insights on microstructure and electrical properties of 3 mol% Y2 O3 –ZrO2 (3YTZP) composites with 0.5, 1, and 1.5 vol% single walled carbon nanotubes (SWNTs). The composites were spark plasma sintered (SPS) in identical conditions at 1250 °C from powder prepared by two different processing routines, with the aim of optimizing the SWNTs dispersion throughout the ceramic matrix. High densification and submicrometric grain size were achieved in all the composites. Electrical properties of the composites were characterized in a wide temperature range, and modeling of the impedance properties was approached by means of an equivalent circuit that allows separation of the individual SWNT bundles contribution to resistance from the resistance due to junctions between bundles. Effects of the homogeneous distribution of SWNTs at the ceramic grain boundaries on the crystalline phases, percolation threshold, total conductivity and evolution of junctions׳ resistivity with temperature were analyzed and discussed.