Thermal shock behaviour of magnesia-spinel composites

Aksel C., Rand B., Riley F., Warren P.

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, vol.24, no.9, pp.2839-2845, 2004 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 24 Issue: 9
  • Publication Date: 2004
  • Doi Number: 10.1016/j.jeurceramsoc.2003.07.017
  • Journal Name: JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2839-2845
  • Keywords: MgAl2O4, MgO, microcracks, spinel, strength, thermal shock, Young's modulus, R-parameters, TEMPERATURE MECHANICAL PROPERTIES, CERAMIC MATERIALS, STRESS RESISTANCE, FRACTURE
  • Anadolu University Affiliated: No

Abstract

The incorporation of up to 30% of spinel powder of median particle sizes 3, 11 and 22 mum into dense magnesia gives improved resistance to thermal shock as indicated both by the R''' thermal shock resistance parameters calculated from measured mechanical properties, and by a standard quench test. The loss of strength of the composite materials in the quench test matched satisfactorily that predicted by the R''' parameter. The maximum benefit from spinel additions was obtained with spinel of the largest particle size, at a loading of 20%. It is postulated that the pre-formed cracks in the composites, resulting from the thermal expansion mismatch between magnesia and spinel, inhibit the accumulation of strain energy during thermal shock. (C) 2003 Elsevier Ltd. All rights reserved.