An oxidation protection system disposed on a substrate is provided, which may comprise a boron layer comprising a boron compound disposed on the substrate; a silicon layer comprising a silicon compound disposed on the boron layer; and at least one sealing layer comprising monoaluminum phosphate and phosphoric acid disposed on the silicon layer.

A method for coating a ceramic matrix composite part with an environmental barrier, the method including a) applying, to a surface of the part, a coating composition including a first powder of a rare earth silicate and a second powder including boron, the coating composition having a ratio R=[mass of the second powder]/[mass of the first powder] of between 0.1% and 5%, and b) sintering the first and second powders to obtain the environmental barrier on the part.

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.

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.

Provided is a cutting tool comprising a base body and a hard carbon film arranged on the base body, in which the hard carbon film includes an amorphous phase and a graphite phase, the degree of crystallinity of the hard carbon film is no more than 6.5%, and the degree of orientation of the graphite phase is no more than 6.

Provided is a cutting tool comprising a base body and a hard carbon film arranged on the base body, in which the hard carbon film includes an amorphous phase and a graphite phase, the degree of crystallinity of the hard carbon film is no more than 6.5%, and the degree of orientation of the graphite phase is no more than 6.

A multilayer protective coating system includes a turbine engine component substrate formed of a ceramic matrix composite material, an environmental barrier coating layer including a rare earth disilicate material deposited directly on the substrate, and a plurality of pairs of alternating layers of the rare earth disilicate material and a rare earth monosilicate material deposited and sintered directly on the environmental barrier coating layer. Each layer of the plurality of pairs of alternating layers is relative less thick as compared with the environmental barrier coating layer.

A coated article including an article having a surface; an oxidation resistant bond coat layer deposited on the surface, the oxidation resistant bond coat layer comprising a metal silicide phase, a crystalline ceramic phase and an amorphous ceramic phase, wherein the metal silicide phase has an aspect ratio greater than 1:1 but less than 50:1.

A coated article including an article having a surface; an oxidation resistant bond coat layer deposited on the surface, the oxidation resistant bond coat layer comprising a metal silicide phase, a crystalline ceramic phase and an amorphous ceramic phase, wherein the metal silicide phase has an aspect ratio greater than 1:1 but less than 50:1.

A turbine engine part coated in at least a first ceramic layer forming a thermal barrier and including a ceramic material with first ceramic fibers dispersed in the first layer. The first layer may have a chemical composition gradient between a material for forming a thermal barrier and a material for providing protection against calcium and magnesium aluminosilicates, which is present at a greater content in an outer zone of the first layer, and/or the first layer may be porous and may present a porosity gradient such that an outer portion of the first layer presents lower porosity.