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Volume 6 Research & Reviews: Journal of Material Sciences
ISSN: 2321-6212 Ceramics 2018
May 14-15, 2018
May 14-15, 2018 | Rome, Italy
4th International Conference and Expo on
Ceramics and Composite Materials
Effect of the homogenization treatment on the microstructure and the electrical conductivity of
3YTZP/graphene nanoplatelet composites
R. Poyato1 , C. López-Pernía1,2, C. Muñoz-Ferreiro2, C. González-Orellana, A. Morales-Rodríguez2 and A. Gallardo-López2
1Instituto de Ciencia de Materiales de Sevilla, ICMS, CSIC-Universidad de Sevilla, Spain
2Departamento de Física de la Materia Condensada, Universidad de Sevilla-ICMS (CSIC), Spain
Nowadays, graphene nanoplatelets (GNPs) are being considered as an emerging class of nanomaterials. GNPs are composed
of ten or more graphene layers, with thickness up to 100 nm, and present unusual mechanical and electrical properties1,2.
These characteristics have motivated a great interest in incorporating these nanostructures as second phase in a ceramic matrix,
in order to enhance the mechanical and functional properties of the final composite3-5. However, one of the main obstacles to
be overcome is obtaining a good dispersion of the GNPs into the ceramic matrix.
In this work, 3YTZP based composites with different GNP contents were prepared using different powder homogenization
methods and electric pulsed discharge sintering (also called spark Plasma Sintering or SPS). Composite powders were prepared
by tip-sonication in isopropanol and/or by planetary ball milling under dry or wet conditions. The effect of milling and
ultrasonic agitation on GNP integrity and particle size has been evaluated by Raman spectroscopy and laser granulometry.
Microstructure of the composites has been analysed by electron microscopy, X-ray diffraction and Raman spectroscopy to
assess the integrity of the GNPs, their degree of dispersion or agglomeration in the ceramic matrix and the stabilization of the
tetragonal phase in the 3YTZP matrix. The relationships between GNP content and dimensions, microstructure and electrical
conductivity, as well as the conduction mechanisms of the composites, have been analysed and discussed.
Recent Publications
1. Jang BZ, Zhamu A (2008) Processing of nanographene platelets (NGPs) and NGP nanocomposites: a review. J Mater Sci
43:5092-5101.
2. Kaiser AB, Gómez-NavarroC, SundaramRS, BurghardM, KernK (2009) Electrical conductionmechanism in chemically
derived grapheme monolayers. Nano Letters 9:1787-1792.
3. Ramirez C, Miranzo P, Belmonte M, Osendi MI, Poza P, Vega-Diaz SM, Terrones M (2014) Extraordinary toughening
enhancement and flexural strength in Si3N4 composites using graphene sheets. Journal of the European Ceramic Society
34:161-169.
4. Román-Manso B, Domingues E, Figueiredo FM, Belmonte M, Miranzo P (2015) Enhanced electrical conductivity of
silicon carbide ceramics by addition of graphene nanoplatelets. Journal of the European Ceramic Society 35: 2723–2731.
5. Gallardo-López A, Márquez-Abril I, Morales-Rodríguez A, Muñoz A, Poyato R (2017) Dense graphene nanoplatelet/
yttria tetragonal zirconia composites: Processing, hardness and electrical conductivity. Ceramics International 43:
11743–11752.
Biography
Dr. Rosalía Poyato completed her . in Physics at the University of Seville and received her PhD in Applied Physics at the Autonoma University of Madrid. After
obtaining PhD, she developed her research at University of Connecticut and Ohio State University (USA), as a postdoctoral research Fulbright fellow. At this moment,
she is a Tenured Researcher at the Materials Science Institute of Seville and her current research interests include processing and characterization of ceramic composites
including carbon nanostructures (carbon nanotubes and multi-layered graphene structures). She has co-authored over 50 papers in international journals. Dr. Poyato is
now co-leader of a research project funded by the Spanish National Science Foundation and the European Feder Funding: Processing and microstructural, mechanical
and electrical characterization of ceramic-graphene composites (MAT2015-67889-P).
R. Poyato et al., Res. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C1-014