摘要:
In accordance with an embodiment of the invention, an article is provided. The article comprises a substrate comprised of silicon containing material, an environmental barrier coating (EBC) overlying the substrate and a thermal barrier coating (TBC) on the environmental barrier coating. The thermal barrier coating comprising a compound having a rhombohedral phase.
摘要:
In accordance with an embodiment of the invention, a thermal barrier coating (TBC) for inclusion in a thermal barrier coating/environmental barrier coating system (TBC/EBC system) for use on a silicon containing material substrate is provided. The TBC comprises a compound having a primary constituent portion and a stabilizer portion stabilizing said primary constituent. The primary constituent portion of the TBC comprises hafnia present in an amount of at least about 5 mol % of the primary constituent. The stabilizer portion of said thermal barrier coating comprises at least one metal oxide comprised of cations with a +2 or +3 valence present in the amount of about 10 to about 40 mol % of the thermal barrier coating.
摘要:
According to an embodiment of the invention, disclosed is a composite comprising a porous thermal barrier coating on a metallic part and an impermeable barrier coating adjacent to the outer surface of the thermal barrier coating. The impermeable barrier coating is dense and non-porous and comprises a rare earth silicate, the impermeable barrier coating thereby preventing infiltration of the contaminant composition into the thermal barrier coating.
摘要:
A coating system for Si-containing materials, particularly Si-based composites used to produce articles exposed to high temperatures. The coating system is a compositionally-graded thermal/environmental barrier coating (T/EBC) system that includes an intermediate layer containing yttria-stabilized hafnia (YSHf) and mullite, alumina and/or an aluminosilicate, which is used in combination with an inner layer between a Si-containing substrate and the intermediate layer and a thermal-insulating top coat overlying the intermediate layer. The intermediate layer provides environmental protection to the silicon-containing substrate, and has a coefficient of thermal expansion between that of the top coat and that of the inner layer so as to serve as a transition layer therebetween. The intermediate layer is particular well suited for use in combination with an inner layer of an alkaline earth metal aluminosilicate (such as BSAS) and a top coat formed of YSZ or YSHf.
摘要:
Thermal barrier coating (TBC) and a method of depositing a TBC having a modulated columnar microstructure that exhibits increased impact resistance. The TBC is deposited to have a columnar microstructure in which columns extend from a substrate surface. The columns having inner regions contacting the surface, outer regions near an outermost surface of the TBC, and interior regions therebetween. The inner regions of the columns are substantially normal to the substrate surface and at least one of the interior and outer regions of the columns are nonaligned with its respective inner regions, so that the columns of the columnar microstructure are continuous but modulated between the inner and outer regions to reduce tensile stresses within the columns resulting from particle impact.
摘要:
An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article further comprises a transition layer between the environmental barrier layer and the top coat, the transition layer comprising zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof. A method for preparing a thermal/environmental barrier coating system on a substrate formed of a silicon-comprising material is also disclosed.
摘要:
An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising hafnia stabilized with from about 0.5 mole % to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article optionally comprises a transition layer between the environmental barrier layer and the top coat. A method for preparing a thermal/environmental barrier coating on a substrate formed of a silicon-comprising material is also disclosed.
摘要:
According to an embodiment of the invention, disclosed is a composite comprising a porous thermal barrier coating on a metallic part and an impermeable barrier coating adjacent to the outer surface of the thermal barrier coating. The impermeable barrier coating is dense and non-porous and comprises a rare earth silicate, the impermeable barrier coating thereby preventing infiltration of the contaminant composition into the thermal barrier coating.
摘要:
An article comprising a substrate formed of a silicon-comprising material, such as an article exposed to the hostile thermal environment of a gas turbine engine. The article further comprises an environmental barrier layer, e.g., an alkaline earth metal aluminosilicate, and a top coat comprising zirconia or hafnia stabilized with up to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof. The article further comprises a transition layer between the environmental barrier layer and the top coat, the transition layer comprising zirconia or hafnia stabilized with up to about 10 mole % of an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof. A method for preparing a thermal/environmental barrier coating system on a substrate formed of a silicon-comprising material is also disclosed.
摘要:
An intermetallic composition suitable for use as an environmentally-protective coating on surfaces of components used in hostile thermal environments, including the turbine, combustor and augmentor sections of a gas turbine engine. The coating contains the gamma-prime (Ni3Al) nickel aluminide intermetallic phase and either the beta (NiAl) nickel aluminide intermetallic phase or the gamma solid solution phase. The coating has an average aluminum content of 14 to 30 atomic percent and an average platinum-group metal content of at least 1 to less than 10 atomic percent, the balance of the coating being nickel, incidental impurities, and optionally hafnium.
摘要翻译:适用于在敌对热环境中使用的组件的表面上用作环境保护涂层的金属间组合物,包括燃气涡轮发动机的涡轮机,燃烧器和增压器部分。 该涂层含有γ-prime(Ni 3 Al 3)铝铝化物金属间相和β(NiAl)镍铝化物金属间相或γ固溶体相。 该涂层的平均铝含量为14〜30原子%,平均铂族金属含量为1〜10原子%以下,其余为镍,附带杂质,以及任选的铪。