Ultrafine SiC Produced via Liquid Phase Sintering

Diletta Sciti 

CNR-ISTEC, Institute of Science and Technology for Ceramics, Via Granarolo 64, Faenza 48018, Italy

Abstract


ULTRAFINE SIC PRODUCED VIA LIQUID PHASE SINTERING,
D. Sciti, S. Guicciardi, A. Bellosi, CNR-ISTEC, Via Granarolo 64, 48018 -
Faenza, Italy

Ceramics with grain sizes down to the nanometer range have attracted a
lot of scientific interest as an increase in hardness, mechanical
strength, Weibull modulus and wear resistance is expected.
SiC ceramics are promising candidate materials for high temperature
structural components in heat engines, heat exchangers and wear
resistant components. Liquid phase sintering of SiC has been widely
investigated as complete densification can be achieved at temperatures
ranging between 1850 and 1900C.
In this work, SiC ceramics having mean grain size of about 150 nm
were produced by hot pressing at 1870C and 30 MPa starting from
different SiC nanosized powders, through liquid phase sintering, that
is formed by the addition of sintering aids (Al[2]O[3]+Y[2]O[3]). The
amount of additives ranges from 6.7 to 10 wt% and the Al[2]O[3]
/Y[2]O[3 ]ratio is varied in order to optimize the sintering behaviour
and microstructure. Grain size and morphology and grain boundary
phases were analysed by XRD, SEM, EDX, TEM. Some mechanical
properties were measured: 4-pt bending strength up to 1300C,
indentation toughness, Vickers hardness and Young modulus.

Legal notice
  • Legal notice:

    Copyrighted materials, (c) Pielaszek Research, all rights reserved.
    The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced, stored in or introduced into a retrieval or caching system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise), or for any purpose, without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
    In every case, proper references including Author(s) name(s) and URL of this webpage: http://science24.com/paper/282 must be provided.

 

Presentation: oral at E-MRS Fall Meeting 2002, by Diletta Sciti
See On-line Journal of E-MRS Fall Meeting 2002

Submitted: 2003-02-16 17:33
Revised:   2009-06-08 12:55
Google
 
Web science24.com
© 1998-2021 pielaszek research, all rights reserved Powered by the Conference Engine