In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and chromium or a chromium compound. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and chromium or a chromium compound. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; at least one of a group four, a group five, or a group six metal or metal compound; boron carbide; water; and surfactant. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; at least one of a group four, a group five, or a group six metal or metal compound; boron carbide; water; and surfactant. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and tungsten. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and tungsten. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and molybdenum or a molybdenum compound. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

In examples, a method for forming a high temperature coating includes applying a barrier coat formulation on a substrate. The barrier coat formulation includes mono-aluminum phosphate; boron carbide; and molybdenum or a molybdenum compound. The method further includes heat treating the barrier coat formulation to form an oxidation-resistant coating layer, wherein a melting point of the oxidation-resistant coating layer is greater than about 800 degrees Celsius ( C.).

A method for forming an oxidation protection system on a composite structure are provided. The method includes applying a composite slurry to the composite structure, wherein the composite slurry comprises boron carbide, silicon carbide, borosilicate glass, an oxygen reactant compound including a silica forming component, and a carrier fluid and heating the composite structure to a temperature sufficient to form a boron-silicon-glass-oxygen reactant layer on the composite structure.

A method for forming an oxidation protection system on a composite structure are provided. The method includes applying a composite slurry to the composite structure, wherein the composite slurry comprises boron carbide, silicon carbide, borosilicate glass, an oxygen reactant compound including a silica forming component, and a carrier fluid and heating the composite structure to a temperature sufficient to form a boron-silicon-glass-oxygen reactant layer on the composite structure.