Issue 11, 2016

Synthesis and characterization of low specific resistance alumina-clay–carbon composites by colloidal processing using sucrose as a soluble carbon source for electrical applications

Abstract

Switching resistors in high voltage circuit breakers require the use of materials with low specific resistance which can sustain high temperatures for short durations, have high thermal conductivity and thermal shock resistance. Materials that satisfy these requirements can be produced by dispersing a conducting phase such as carbon black, graphite, CNT, graphene in ceramic matrix. Dispersion of these ultrafine forms of carbon to obtain contiguity at lower volume fractions is a challenge. In this work, alumina-clay–carbon composites were fabricated by using alumina-clay slurries with addition of sucrose as a soluble carbon source. Sucrose is converted into conducting carbon with heat treatment at high temperatures. Alumina-clay–carbon composites made using a soluble source (sucrose) sintered at 1400 °C showed resistor behaviour even at carbon contents less than 1 wt% produced by graphitization of sucrose at high temperature. Raman spectroscopic scans over a wide area of the samples confirmed uniform distribution of carbon within the ceramic matrix. Resistivity of the alumina-clay–carbon composites varied between 30 ohm cm to 2 ohm cm for sucrose additions (equivalent to carbon content) of 2–9 wt%. The resistivity of the composite samples produced with the use of sucrose was significantly lower than that of samples produced by dispersing carbon black as the conducting phase.

Graphical abstract: Synthesis and characterization of low specific resistance alumina-clay–carbon composites by colloidal processing using sucrose as a soluble carbon source for electrical applications

Article information

Article type
Paper
Submitted
11 Sep 2015
Accepted
11 Jan 2016
First published
14 Jan 2016

RSC Adv., 2016,6, 8705-8713

Author version available

Synthesis and characterization of low specific resistance alumina-clay–carbon composites by colloidal processing using sucrose as a soluble carbon source for electrical applications

R. Kumar and P. Bhargava, RSC Adv., 2016, 6, 8705 DOI: 10.1039/C5RA18675G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements