Mullite morphology in fired kaolinite/halloysite clays

Formation mechanism and microstructure development in acicular mullite ceramics fabricated by controlled decomposition of fluorotopaz

“…The presence of mullite in sintered porcelain bodies has been known for a long time. 5 More recently Perera and Allot grew 0.5 m wide and 5 m long mullite needles by firing kaolinite between 1400 and 1600 • C. 6 Li et al, 7 Hashimoto and Yamaguchi 8 and De Sousa et al 9 produced mullite needles from melts in flux-assisted processes but these needles typically were small and/or required temperatures well over 1300 • C (which also led to simultaneous densification). Other researchers used gas transport mechanisms to grow mullite based on the decomposition of volatile fluorine compounds.…”

Mullite Whiskers Derived from an Oxide Mixture Activated by a Mechanochemical Process

“…[6] The flame-made particles, like P25 nanoparticles, are prepared at elevated temperatures (> 1000 C) with short residence time resulting in crystalline anatase and rutile powders. The former process produces titania particles by oxidation of titaninium tetrachloride (TiCl 4 ) vapor in a flame reactor.…”

“…[5] Needle-like mullite could be obtained by firing kaolin minerals at temperatures in the range 1400±1600 C. [6] Anisotropic grain growth of mullite was reported by Messing et al by doping with B 2 O 3 or TiO 2 . mixture of xerogel, silica gel, and aluminum fluoride by calcining at high temperature (900±1600 C).…”

Nanocrystalline Mullite Synthesis at a Low Temperature: Effect of Copper Ions

“…Mullite research is gaining importance because of the excellent properties it exhibits such as high thermal and chemical stability, high creep resistance, a low thermal coefficient of expansion, and good dielectric properties 1–4 …”