Abstract: A cast magnesium oxide based structure is utilized as a heat storage material. In preferred embodiments, the magnesium oxide heat storage material is cast directly about a source of heat. In another embodiment, a block of cast magnesium oxide based heat storage material is placed in contact with a source of heat forraising the temperature and storing heat and later moved to a different environment for transferring heat to that environment.

Abstract: The invention relates to low-expansion ceramics, the chemical composition of which consists of 1.2 to 20% by weight of magnesia (MgO), 6.5 to 68% by weight of alumina (Al.sub.2 O.sub.3), 19 to 80% by weight of titanium in terms of titanium oxide (TiO.sub.2), 1 to 20% by weight of silica (SiO.sub.2), and 0.5 to 20% by weight of iron in terms of ferric oxide (Fe.sub.2 O.sub.3); the major component of crystalline phase thereof is a solid solution of magnesium oxide-aluminum oxide-titanium dioxide-silicon oxide-iron oxide; the ceramics have a coefficient of thermal expansion of not more than 20.times.10.sup.-7 (1/.degree.C.) in a temperature range of 25.degree. C. to 800.degree. C., a four-point flexural strength of not smaller than 50 kg/cm.sup.2 at room temperature, and a melting point of not lower than 1,500.degree. C.

Abstract: The present invention relates to low-expansion ceramics having a chemical composition of the ceramics essentially consisting of 2 to 20% by weight of magnesia (MgO), 10 to 68% by weight of alumina (Al.sub.2 O.sub.3), and 30 to 80% by weight of titanium in terms of titanium oxide (TiO.sub.2), wherein the major component of crystalline phase thereof is magnesium-alumium-titanate phase, and the ceramics have a coefficient of thermal expansion of not more than 20.times.10.sup.-7 (1/.degree.C.) in a temperature range of 25.degree. C. to 800.degree. C. and a melting point of not lower than 1,500.degree. C., wherein the magnesium-alumium-titanate phase as the major component of the crystalline phase thereof is given by a chemical formula Mg.sub.10x Al.sub.8y Ti.sub.5(1-x-y) O.sub.(10+2y), here 0.02.ltoreq.x.ltoreq.0.20, 0.10.ltoreq.y.ltoreq.0.68, and 0.20.ltoreq.(x+y).ltoreq.0.

Abstract: A hot repair gun refractory mix which comprises a granulated material which is preformed by covering the surface of a carbonaceous substance particle with a fine refractory powder.

Abstract: Cordierite ceramic honeycomb consisting mainly of cordierite in crystal phase and containing not more than 20% by weight of at least one crystal selected from the group consisting of spinel, mullite and corundum and having a thermal expansion coefficient at a temperature range of 25.degree.-1,000.degree. C. being less than 22.times.10.sup.-7 (1/.degree.C.).

Abstract: The present invention relates to ZrO.sub.2 -MgO-Al.sub.2 O.sub.3 -SiO.sub.2 ceramic materials having improved thermal stability and corrosion resistant properties. The utilization of these ceramic materials as heat exchangers for gas turbine engines is also disclosed.