Abstract
The changes taking place during the dynamic heating of pyrophyllite up to 1430° are investigated by means of scanning electron microscopy. X-ray diffraction was used as a complementary technique for phase identification, being pyrophyllite and its dehydroxylate, mullite and cristobalite. The different morphologies developed when pyrophyllite is progressively transformed by heating into new phases such as mullite and cristobalite are revealed and presented in this study. It is established that pyrophyllite dehydroxylate shows the same shape as the unheated material. However, upon further heating, the formation of mullite and later cristobalite, as well as the increase of the glassy phase, contribute to the observed microstructures.
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Sanchez-Soto, P.J., Perez-Rodriguez, J.L. SEM study of pyrophyllite high-temperature transformations. J Mater Sci 24, 3774–3778 (1989). https://doi.org/10.1007/BF02385769
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DOI: https://doi.org/10.1007/BF02385769