Premium
Reinvestigation of Al–Si Spinel Phase in Diphasic Al 2 O 3 –SiO 2 Gel
Author(s) -
Chakraborty Akshoy Kr.
Publication year - 2005
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2004.00018.x
Subject(s) - mullite , spinel , stoichiometry , materials science , phase (matter) , amorphous solid , atmospheric temperature range , chemical engineering , sol gel , diffraction , solid solution , mineralogy , crystallography , chemistry , metallurgy , thermodynamics , nanotechnology , ceramic , organic chemistry , physics , optics , engineering
Mechanical mixture of γ‐Al 2 O 3 and amorphous SiO 2 , and diphasic Al 2 O 3 /SiO 2 gels of three different compositions were synthesized. They were subjected to heat treatment to various temperatures in the range 900°–1600°C. Qualitative X‐ray diffraction data show that these diphasic gels do not crystallize to a combined mixture of θ‐Al 2 O 3 and α‐Al 2 O 3 polymorphs at the intermediate stage, prior to mullite formation. Estimated mullite formation data show that the course of its formation from mixed oxides was different from that of diphasic gels. Results are compared with previous findings and the concept of Al–Si spinel formation in the phase transformation of stoichiometric diphasic gel system is substantiated.