A composition is generally provided that includes a silicon-containing material (e.g., silicon metal and/or a silicide) and a boron-doped refractory compound, such as about 0.001% to about 85% by volume of the boron-doped refractory compound (e.g., about 1% to about 60% by volume). In one embodiment, a bond coating on a surface of a ceramic component is generally provided with the bond coating including such a composition, with the silicon-containing material is silicon metal.

A compound is provided that has the formula: Ln.sub.4-x-zB.sub.xD.sub.zM.sub.2-n-yA.sub.nB.sub.yO.sub.9, where Ln comprises La, Ce, Pr, Nd, Pm, Sm, or a mixture thereof; x is 0 to about 2; D is La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof, where: D is not equal to Ln; if D is La, Ce, Pr, Nd, Pm, Sm, or a mixture thereof, then z is 0 to less than 4; if D is Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof, then z is 0 to about 2; M comprises Ga, Al, or a combination thereof; A comprises Fe, In, or a combination thereof; n is 0 to about 1; y is 0 to about 1; and x+y is greater than 0. In one embodiment, a composition is generally provided that includes a silicon-containing material and such a boron-doped refractory compound.

A compound is provided that has the formula: Ln.sub.4-x-zB.sub.xD.sub.zM.sub.2-n-yA.sub.nB.sub.yO.sub.9, where Ln comprises La, Ce, Pr, Nd, Pm, Sm, or a mixture thereof; x is 0 to about 2; D is La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof, where: D is not equal to Ln; if D is La, Ce, Pr, Nd, Pm, Sm, or a mixture thereof, then z is 0 to less than 4; if D is Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof, then z is 0 to about 2; M comprises Ga, Al, or a combination thereof; A comprises Fe, In, or a combination thereof; n is 0 to about 1; y is 0 to about 1; and x+y is greater than 0. In one embodiment, a composition is generally provided that includes a silicon-containing material and such a boron-doped refractory compound.

A compound is generally provided that has the formula: Ln.sub.3-xB.sub.xM.sub.5-yB.sub.yO.sub.12, where Ln comprises Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof; x is 0 to about 1.5; M comprises Ga, In, Al, Fe, or a combination thereof; y is 0 to about 2.5; and x+y is greater than 0. A composition is also provided that includes a silicon-containing material (e.g., silicon metal and/or a silicide) and the boron-doped refractory compound having the formula described above, such as about 0.001% to about 85% by volume of the boron-doped refractory compound.

A compound is generally provided that has the formula: Ln.sub.3-xB.sub.xM.sub.5-yB.sub.yO.sub.12, where Ln comprises Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, or a mixture thereof; x is 0 to about 1.5; M comprises Ga, In, Al, Fe, or a combination thereof; y is 0 to about 2.5; and x+y is greater than 0. A composition is also provided that includes a silicon-containing material (e.g., silicon metal and/or a silicide) and the boron-doped refractory compound having the formula described above, such as about 0.001% to about 85% by volume of the boron-doped refractory compound.

A coating composition for improving the sag resistance of a gypsum panel or a fibrous panel, the composition including 25 to 100 wt. % alkali metal polyborate silicate inorganic binder, based on the total weight of the dry coating. The inorganic binder includes alkali metal polyborate silicate resulting from combining alkali metal polyborate and alkali metal silicate. Further provided are fibrous panels having a backing side and an opposing facing side including a coating of the inorganic binder, and methods of preparing same. Further provided are gypsum panels having a backing side and an opposing facing side including a coating of the inorganic binder, and methods of preparing same.

The disclosure provides for an article including a substrate, an environmental barrier coating (EBC), a bondcoat and a boron source. The substrate may include a silicon-including ceramic material. The EBC may be disposed over the substrate, and the bondcoat may disposed between the substrate and the EBC. The bondcoat may include silicon. The boron source may be disposed within the article to provide an effective amount of boron to form an oxide including silicon and at least 0.1 weight percent boron during exposure of the bondcoat to an oxidizing environment at a temperature greater than 900 degrees Celsius. The oxide may be a borosilicate glass that is substantially devitrification resistant to prevent spallation of the EBC and thereby enhance the temperature capability of the article.

The disclosure provides for an article including a substrate, an environmental barrier coating (EBC), a bondcoat and a boron source. The substrate may include a silicon-including ceramic material. The EBC may be disposed over the substrate, and the bondcoat may disposed between the substrate and the EBC. The bondcoat may include silicon. The boron source may be disposed within the article to provide an effective amount of boron to form an oxide including silicon and at least 0.1 weight percent boron during exposure of the bondcoat to an oxidizing environment at a temperature greater than 900 degrees Celsius. The oxide may be a borosilicate glass that is substantially devitrification resistant to prevent spallation of the EBC and thereby enhance the temperature capability of the article.

A porous refractory in the K.sub.2OSiO.sub.2B.sub.2O.sub.3 system is formed by chemical direct foaming by heating to over 600 C., resulting in adherent black or white foam. The foam can function as highly porous thermal insulation, a high or low thermal emissivity surface, as a sealant for deteriorated refractory surfaces, as a filler for pockmarks/holes/gaps or as a bonding agent for parts with large gaps between them.

A porous refractory in the K.sub.2OSiO.sub.2B.sub.2O.sub.3 system is formed by chemical direct foaming by heating to over 600 C., resulting in adherent black or white foam. The foam can function as highly porous thermal insulation, a high or low thermal emissivity surface, as a sealant for deteriorated refractory surfaces, as a filler for pockmarks/holes/gaps or as a bonding agent for parts with large gaps between them.