| In this paper, mineral composition and mullitization and related products of andalusite from Xijiang was studied. This can offer theory instruction for fabricating low creep mullite-corundum materials. At first, mineral composition and distributing of impurities in andalusite grains were studied by SEM and EDS. The results showed that main mineral impurities were biotite, ilmenite, clay species, the wall rock conglutinated at brim of andalusite and impurities in the chiastolitic cruciform pattern were easily removed, but the small impurities in andalusite grain were hardly removed. Secondly, the mullitization characteristic and thermal expansion properties of this andalusite were studied. The results showed that the mullite content increased with temperature and sokingtime increased,and mullitization of andalusite with samller size or more impurities was faster. Andalusite expansed below 1000℃ and shrinked above 1000℃ because of the effect of impurities, up to 1300℃ the shrink counteracted by the expansion generated by mullitization of andalusite, consequently the sample expansed again. Finally, the properties of mullitie-corundum materials made up of high-alumina grains and andalusite fines were studied, the results showed that the properties of materials added bauxite and sintered mullite grains were bad, but the materials added corundum and andalusite grains had a high creep resistance. So as a raw material to producte the refractories of high creep resistance, andalusite was very valuable.
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