A method for forming a high temperature coating includes applying carbon powder to a surface of a carbon/carbon (C/C) composite substrate to force the carbon powder into one or more surface voids of the surface of the C/C composite substrate. The carbon powder has a substantially same composition and morphology as a surface portion of the C/C composite substrate. The method includes applying a metal slurry to the surface of the C/C composite substrate following the application of the carbon powder and reacting a metal of the metal slurry with carbon of the carbon powder and carbon of the surface portion of the C/C composite substrate to form a metal-rich antioxidant layer of a metal carbide on the C/C composite substrate.

A method for forming an oxidation protection system on a composite structure is provided, which may comprise applying a ceramic layer slurry to the composite structure, wherein the ceramic layer slurry may comprise aluminum and silicon in a solvent or carrier fluid; heating the composite structure to form a ceramic layer on the composite structure, wherein the ceramic layer may comprise aluminum nitride; applying a sealing slurry to the composite structure, wherein the sealing slurry may comprise a sealing pre-slurry composition and a sealing carrier fluid, wherein the sealing pre-slurry composition may comprise a sealing phosphate glass composition; and/or heating the composite structure to form a sealing layer on the composite structure.

A method for forming an oxidation protection system on a composite structure is provided, which may comprise applying a ceramic layer slurry to the composite structure, wherein the ceramic layer slurry may comprise aluminum and silicon in a solvent or carrier fluid; heating the composite structure to form a ceramic layer on the composite structure, wherein the ceramic layer may comprise aluminum nitride; applying a sealing slurry to the composite structure, wherein the sealing slurry may comprise a sealing pre-slurry composition and a sealing carrier fluid, wherein the sealing pre-slurry composition may comprise a sealing phosphate glass composition; and/or heating the composite structure to form a sealing layer on the composite structure.

Described are molds that include a ceramic material at a surface, as well as methods of forming the molds, and methods of using the molds; the ceramic material is constituted substantially, mostly, or entirely of three elemental components designated M, A, and X; the “M” component is at least one transition metal; the “A” component is one or a combination of Si, Al, Ge, Pb, Sn, Ga, P, S, In, As, Tl, and Cd; and the “X” component is carbon, nitrogen, or a combination thereof.

Described are molds that include a ceramic material at a surface, as well as methods of forming the molds, and methods of using the molds; the ceramic material is constituted substantially, mostly, or entirely of three elemental components designated M, A, and X; the “M” component is at least one transition metal; the “A” component is one or a combination of Si, Al, Ge, Pb, Sn, Ga, P, S, In, As, Tl, and Cd; and the “X” component is carbon, nitrogen, or a combination thereof.

A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein a content of the cubic boron nitride is 40 volume % or more and 70 volume % or less; a content of the binder phase is 30 volume % or more and 60 volume % or less; an average particle size of the cubic boron nitride is 0.1 μm or more and 3.0 μm or less; the binder phase contains TiN and/or TiCN, and TiB.sub.2 and contains substantially no AIN and/or Al.sub.2O.sub.3, the binder phase has a TiB.sub.2 (101) plane that shows a maximum peak position (2θ) in X-ray diffraction of 44.2° or more; and I.sub.2/I.sub.1 is 0.10 or more and 0.55 or less, where denotes an X-ray diffraction intensity of a (111) plane of the cubic boron nitride and I.sub.2 denotes an X-ray diffraction intensity of a (101) plane of TiB.sub.2 of the binder phase.

A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein a content of the cubic boron nitride is 40 volume % or more and 70 volume % or less; a content of the binder phase is 30 volume % or more and 60 volume % or less; an average particle size of the cubic boron nitride is 0.1 μm or more and 3.0 μm or less; the binder phase contains TiN and/or TiCN, and TiB.sub.2 and contains substantially no AIN and/or Al.sub.2O.sub.3, the binder phase has a TiB.sub.2 (101) plane that shows a maximum peak position (2θ) in X-ray diffraction of 44.2° or more; and I.sub.2/I.sub.1 is 0.10 or more and 0.55 or less, where denotes an X-ray diffraction intensity of a (111) plane of the cubic boron nitride and I.sub.2 denotes an X-ray diffraction intensity of a (101) plane of TiB.sub.2 of the binder phase.

A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein a content of the cubic boron nitride is 40 volume % or more and 80 volume % or less; a content of the binder phase is 20 volume % or more and 60 volume % or less; an average particle size of the cubic boron nitride is 0.5 μm or more and 4.0 μm or less; the binder phase contains TiC and TiB.sub.2 and contains substantially no AlN and/or Al.sub.2O.sub.3; a (101) plane of TiB.sub.2 in the binder phase shows a maximum peak position (2θ) in X-ray diffraction of 44.2° or more; and a (200) plane of TiC in the binder phase shows a maximum peak position (2θ) in X-ray diffraction of less than 42.1°.

A cubic boron nitride sintered body including cubic boron nitride and a binder phase, wherein a content of the cubic boron nitride is 40 volume % or more and 80 volume % or less; a content of the binder phase is 20 volume % or more and 60 volume % or less; an average particle size of the cubic boron nitride is 0.5 μm or more and 4.0 μm or less; the binder phase contains TiC and TiB.sub.2 and contains substantially no AlN and/or Al.sub.2O.sub.3; a (101) plane of TiB.sub.2 in the binder phase shows a maximum peak position (2θ) in X-ray diffraction of 44.2° or more; and a (200) plane of TiC in the binder phase shows a maximum peak position (2θ) in X-ray diffraction of less than 42.1°.

Provided is a cutting tool comprising a base body and a hard carbon film arranged on the base body, in which, when the cross section of the hard carbon film is observed using a high angle annular dark field scanning transmission electron microscope, the area proportion of black regions with an equivalent circle diameter of 10 nm or more is 0.7% or less, and the hard carbon film has a hydrogen content of 5 atom% or less.