Tailoring the properties of spark plasma sintered SiAlON containing graphene nanoplatelets by using different exfoliation and size reduction techniques: Anisotropic electrical properties


BAŞKUT S., Cinar A., SEYHAN A. T., TURAN S.

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, vol.38, no.11, pp.3787-3792, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 38 Issue: 11
  • Publication Date: 2018
  • Doi Number: 10.1016/j.jeurceramsoc.2018.04.066
  • Journal Name: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.3787-3792
  • Keywords: Graphene nanoplatelets (GNPs), Electrical conductivity, Microfluidization, Lotgering factor, Si3N4, NITRIDE COMPOSITES, THERMAL-PROPERTIES, ADVANCED CERAMICS, CONDUCTIVITY, FABRICATION
  • Anadolu University Affiliated: Yes

Abstract

Insulating SiAlON ceramics can be machined into complex shapes if the electrical conductivities can be increased with additives. Therefore, the microfluidization technique was used as an alternative to traditional sonication for exfoliation and homogenization of GNPs to investigate the effects of different exfoliation, size reduction and homogenization techniques on the microstructure, electrical conductivity and percolation threshold values of GNPs-SiAlON composites. 2.85, 5.70 and 11.40 vol. % sonicated and sonicated + microfluidized GNPs added into SiAlON matrix and were densified by using SPS technique. Due to their thinner and smaller platelet size, microfluidized GNPs dispersed more homogeneously compared to the sonicated GNPs in the SiAlON matrix. Electrical conductivities of the microfluidized GNPs-SiAlON composites were similar to 70-200% higher than sonicated GNPs-SiAlON in the both measured directions. Lower percolation thresholds were achieved when sonicated + microfluidized GNPs used in comparison to sonicated GNPs containing composites. Electrical conductivities in the in-plane direction were also higher than through-plane direction.