Body made of a ceramic material, the body having as an integral part thereof a surface region reaching from the surface of the body down to a predetermined depth. According to the invention, the surface region is enriched with a magnesium component thereby forming a hydrophilic surface area.

Disclosed is a calcium aluminate cement, including a calcium aluminate with a first crystallised mineralogical phase of calcium dialuminate CA2 including one calcium oxide CaO for two aluminium oxides Al.sub.2O.sub.3 and/or a second crystallised mineralogical phase of dicalcium alumina silicate C2AS including two calcium oxides CaO for one aluminium oxide Al.sub.2O.sub.3 and one silicon dioxide SiO.sub.2. The mass fraction of all of the first and second mineralogical phases in the calcium aluminate is greater than or equal to 80%.

A blade outer air seal has at least one internal surface and a layer atop the at least one internal surface. The layer has: a matrix comprising at least one of hafnium silicate (HfSiO.sub.4) and zirconium silicate (ZrSiO.sub.4), ytterbium disilicate (Yb.sub.2Si.sub.2O.sub.7); and barium magnesium alumino silicate (BMAS) or other alkaline earth aluminosilicate.

A blade outer air seal has at least one internal surface and a layer atop the at least one internal surface. The layer has: a matrix comprising at least one of hafnium silicate (HfSiO.sub.4) and zirconium silicate (ZrSiO.sub.4), ytterbium disilicate (Yb.sub.2Si.sub.2O.sub.7); and barium magnesium alumino silicate (BMAS) or other alkaline earth aluminosilicate.

The invention provides novel methods and novel additive compositions and use thereof in a wide range of concrete production for improving properties of concrete materials, such as durability and aestheticity. The methods and compositions of the invention may be applied in a variety of cement and concrete components in the infrastructure, construction, pavement and landscaping industries.

The invention provides novel aerated composite materials made from a carbonatable calcium silicate composition, and formulations and methods of manufacture and use thereof, in particular, the use of novel additive mineral compositions in the form of magnesium, magnesium salts or magnesium oxides, to improve physical chemical properties of low density concrete materials. The low density, aerated material is comprised of calcium carbonate (CaCO.sub.3) and silica (SiO.sub.2), as cured products of carbonatable calcium silicate compositions.

The invention provides novel aerated composite materials made from a carbonatable calcium silicate composition, and formulations and methods of manufacture and use thereof, in particular, the use of novel additive mineral compositions in the form of magnesium, magnesium salts or magnesium oxides, to improve physical chemical properties of low density concrete materials. The low density, aerated material is comprised of calcium carbonate (CaCO.sub.3) and silica (SiO.sub.2), as cured products of carbonatable calcium silicate compositions.

According to some embodiments, a curable mixture configured to set in the presence of water, wherein the mixture comprises magnesium oxide, a primary cementitious component and at least one accelerant. A proportion by weight of the primary cementitious component is 80% to 120% of a proportion of magnesium oxide by weight.

An article has a substrate and a layer atop the substrate. The layer has: a matrix comprising at least one of hafnium silicate (HfSiO.sub.4) and ytterbium disilicate (Yb.sub.2Si.sub.2O.sub.7); and barium magnesium alumino silicate (BMAS).

An article has a substrate and a layer atop the substrate. The layer has: a matrix comprising at least one of hafnium silicate (HfSiO.sub.4) and ytterbium disilicate (Yb.sub.2Si.sub.2O.sub.7); and barium magnesium alumino silicate (BMAS).