Elaboration and Characterization of Mullite Refractory Products from Moroccan Andalusite

Mostafa Sardy, Abdelhak Arib, Kacem El Abbassi, Moussa Gomina

Centre for Study and Research of Mineral Phosphates, Casablanca, Morocco.
CRISMAT, UMR 6508 ENSICAEN/CNRS, Caen, France..
EMPM-LPCMI, Faculty of Science of A?n Chock, Casablanca, Morocco.

DOI: 10.4236/njgc.2012.23017                

Abstract

Enrichment of schist mined in Morocco resulted in an extract essentially made of andalusite, quartz and muscovite, which was investigated with the aim to synthesize mullite refractory materials. X-ray diffraction analysis was used to assess phase transformations upon heating at different temperatures. Mullite formation starts as early as 1200℃ and seems almost total at 1450℃. This process correlates with a weak shrinkage (3.5% at 1450℃) and the formation of an important glass phase. Green compacts obtained by unidirectional pressing the extract powder were heated under air in the temperature range 1200℃ - 1600℃. Chemical and mechanical properties of these materials were investigated and correlated with their microstructure.

Keywords

Andalusite; Mullite Refractory; Structure; Mechanical Properties

Conflicts of Interest

The authors declare no conflicts of interest.

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