Al/Si ordering in mullite

Nanocomposite mullite/mullite powders by spray pyrolysis

A mullite/mullite nanocomposite powder has been synthesized, composed of nanometer-size 3Al2O3 · 2SiO2 (‘3 : 2’) mullite precipitates within a matrix of the high alumina 2Al2O3 · SiO2 (‘2 : 1’) mullite. Historically, the transition from the metastable high-alumina phase to the thermodynamically stable ‘3 : 2’ phase of mullite has been thought to be a continuous process, involving a continuous s...

Microwave Sintering of Mullite

Microwave sintering possesses unique attributes and has the potential to be development as a new technique for controlling microstructure and to improve the properties of advanced ceramics. Because microwave radiation penetrates most ceramics, uniform volumetric heating is possible. Thermal gradients, which are produced during conventional sintering because of conductive and radioactive heat tr...

Mullite-alumina functionally gradient ceramics

Cracks free mullite-alumina Functionally Gradient Ceramics (FGC) have been obtained by sequential slip casting of Mullite-alumina slurries with diserent mullite/alumina ratios. These slurries were prepared with 65 % solids content and viscosities rangingpom 10 to 40 mPa.s. 7he presence of cracks perpendicular to the FGC layers have been attributed to residual stresses developed because of the m...

Superstructure of Mullite-type KAl9O14

Large whiskers of a new KAl9O14 polymorph with mullite-type structure were synthesized. The chemical composition of the crystals was confirmed by energy-dispersive X-ray spectroscopy, and the structure was determined using single-crystal X-ray diffraction. Nanosized twin domains and one-dimensional diffuse scattering were observed utilizing transmission electron microscopy. The compound crystal...

Preparation of High Purity Mullite Ceramics