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By choosing appropriate stabilizing additions and optimizing the thermal treatment, aluminum titanate with a low thermal expansion coefficient (TEC) (minus 3.38.10 - 6 K - 1 in the interval of 20 - 200 °C) and hysteresis (0.07 % at 400 °C) was obtained. The material was used as an additive for decreasing the TEC of alumina. Destructive thermal stresses were overcome by optimizing the milling and homogenization technique. The sintering rates, phase content and microstructure are described.

An influence of β-eucryptite glassceramics on the sintering ability, sintering mechanisms, and structure of alumna ceramics has been researched by methods of DTA, TG, DTG, XRD, dilatometry, optical and electronic microscopy. The thermal incompatibility between Al 2 O 3 and β-eucryptite glassceramics that results from the difference between their thermal coefficients of expansion (TEC) has been overcome by use of superfine powders and thorough blending of the base mixture. A phase composition, microstructure, TEC, mechanical and electrical properties, and thermal-shock resistance of alumina ceramics containing β-eucryptite glassceramics have been determined. A possibility of replacing β-eucryptite glassceramics by the equivalent amount of Li 2 O.2SiO 2 containing glass or a mixture of Li 2 CO 3 . SiO 2 powders has been demonstrated.