摘要:
An article is coasted by preparing a coating source having an aluminum halide, a fluoride or an iodide of a modifying element as a source of the modifying element, and a carrier gas. The modifying element is zirconium, hafnium, and yttrium, or combinations thereof. The coating source is contacted to the article, and the coating source and the article are heated to a coating temperature of at least about 1850° F. for a period of time sufficient to permit aluminum and the modifying element to coat onto the surface of the article. The preferred fluorides of modifying elements are zirconium tetrafluoride and hafnium tetrafluoride.
摘要:
A protective overlay coating for articles used in hostile thermal environments, and particularly for use as a bond coat for a thermal barrier coating deposited on the coating. The coating is predominantly beta-phase NiAl into which a platinum-group metal is incorporated, yielding a coating system capable of exhibiting improved spallation resistance as compared to prior bond coat materials containing platinum, must notably the platinum aluminide diffusion coatings. A preferred composition for the beta-phase NiAl overlay coating further contains chromium and zirconium or hafnium.
摘要:
A thermal barrier coating (TBC) (26) for a component (10) intended for use in a hostile environment, such as the superalloy turbine, combustor and augmentor components of a gas turbine engine. The TBC (26) is formed of at least partially stabilized zirconia, preferably yttria-stabilized zirconia (YSZ), and exhibits improved strength and fracture toughness as a result of containing a dispersion of chromia precipitates or particles (32). The TBC (26) preferably consists essentially of YSZ and the chromia particles (32), which are preferably dispersed throughout the microstructure of the TBC (26), including the YSZ grains (30) and grain boundaries. The chromia particles (32) constitute at least 1 to about 10 volume percent of the TBC (26).
摘要:
A thermal barrier coating (TBC) for a component intended for use in a hostile environment, such as the superalloy turbine, combustor and augmentor components of a gas turbine engine. The TBC is formed of zirconia that is partially stabilized with yttria (YSZ), preferably not more than 3 weight percent yttria, and to which one or more additional metal oxides are alloyed to increase crystallographic defects and lattice strains in the TBC grains and/or form precipitates of zirconia and/or compound(s) of zirconia and/or yttria and the additional metal oxide(s), the inclusion of which reduces the thermal conductivity of the YSZ to levels lower than conventional 6-8% YSZ. Improvements are particularly contemplated for TBC having a columnar grain structure, such as those deposited by EBPVD and other PVD techniques.
摘要:
A surface of a nickel-base article such as an internal surface of a gas turbine airfoil is protected with a donor layer of aluminum and at least one other element. To form the protective layer, a donor alloy is contacted to the protected surface of the article, and simultaneously the article and the donor alloy are heated to a coating temperature that is greater than about 0.7 of the absolute solidus temperature of the donor alloy but is such that the donor alloy remains in the form of a condensed phase contacting the protected surface of the article. The donor alloy is thereafter interdiffused into the protected surface of the article.
摘要:
Coatings suitable for use as protective oxide-forming coatings on Nb-based substrates exposed to high temperatures and oxidative environments. The coatings contain chromium and/or molybdenum, preferably contains silicon, and optionally contains niobium, titanium, hafnium, iron, rhenium, tantalum, and/or tungsten, which in combination form multiple intermetallic phases, which in combination form one or more intermetallic phases that promote the formation of a slow-growing oxide scale. Depending on the particular coating composition, the intermetallic phases maybe: a silicon-modified Cr2Nb Laves phase and optionally a chromium solid solution phase, a CrNbSi intermetallic phase, and/or an M3Si intermetallic phase where M is niobium, titanium, and/or chromium; or M5Si3, MSi2 and/or M3Si2 where M is molybdenum, niobium, titanium, chromium, hafnium, iron, rhenium, tantalum, and/or tungsten.
摘要翻译:适用于暴露于高温和氧化环境的Nb基基底上的保护性氧化物形成涂层的涂料。 涂层含有铬和/或钼,优选含有硅,并且任选地包含铌,钛,铪,铁,铼,钽和/或钨,其组合形成多个金属间相,其组合形成一个或多个金属间相 促进形成缓慢生长的氧化皮。 根据具体的涂层组成,金属间化合物相可以是硅改性的Cr 2 Nb Laves相和任选的铬固溶体相,CrNbSi金属间相和/或M3Si金属间相,其中M是铌,钛和/或铬 ; 或M5Si3,MSi2和/或M3Si2,其中M是钼,铌,钛,铬,铪,铁,铼,钽和/或钨。
摘要:
Coatings suitable for use as protective oxide-forming coatings on Nb-based substrates exposed to high temperatures and oxidative environments. The coatings contain chromium and/or molybdenum, preferably contains silicon, and optionally contains niobium, titanium, hafnium, iron, rhenium, tantalum, and/or tungsten, which in combination form multiple intermetallic phases, which in combination form one or more intermetallic phases that promote the formation of a slow-growing oxide scale. Depending on the particular coating composition, the intermetallic phases may be: a silicon-modified Cr2Nb Laves phase and optionally a chromium solid solution phase, a CrNbSi intermetallic phase, and/or an M3Si intermetallic phase where M is niobium, titanium, and/or chromium; or M5Si3, MSi2 and/or M3Si2 where M is molybdenum, niobium, titanium, chromium, hafnium, iron, rhenium, tantalum, and/or tungsten.
摘要翻译:适用于暴露于高温和氧化环境的Nb基基底上的保护性氧化物形成涂层的涂料。 涂层含有铬和/或钼,优选含有硅,并且任选地包含铌,钛,铪,铁,铼,钽和/或钨,其组合形成多个金属间相,其组合形成一个或多个金属间相 促进形成缓慢生长的氧化皮。 根据特定的涂料组合物,金属间相可以是:硅改性的Cr 2 Nb Laves相和任选的铬固溶相,CrNbSi金属间相和/或M3Si金属间相,其中M是铌,钛和/或 铬; 或M5Si3,MSi2和/或M3Si2,其中M是钼,铌,钛,铬,铪,铁,铼,钽和/或钨。
摘要:
A PVD process and apparatus (120) for depositing a coating (132) from multiple sources (110, 111) of different materials. The process and apparatus (120) are particulaity intended to deposit a beta-nickel aluminide coating (132) containing one or more elements whose vapor pressures are lower than NiAl. The PVD process and apparatus (120) entail feeding at least two materials (110, 111) into a coating chamber (122) and evaporating the materials (110, 111) at different rates from separate molten pools (114, 115) thereof. Articles (130) to be coated are suspended within the coating chamber (122), and transported with a support apparatus (118) relative to the two molten pools (114, 115) so as to deposit a coating (132) with a controlled composition that is a mixture of the first and second materials (110, 111).
摘要:
A method for coating an article includes preparing a coating precursor paint including aluminum-containing pigment particles, a temporary organic binder comprising an acrylic, and a solvent for the temporary organic binder. The coating precursor paint is applied to a surface of the article and thereafter heated to a temperature of from about 1200° F. to about 2100° F. in a non-oxidizing environment.
摘要:
A thermal barrier coating (TBC) for a component intended for use in a hostile environment, such as the superalloy turbine, combustor and augmentor components of a gas turbine engine. The TBC is formed to contain small amounts of alumina precipitates dispersed throughout the grain boundaries and pores of the TBC to getter oxide impurities that would otherwise allow or promote grain sintering and coarsening and pore coarsening, the consequence of which would be densification of the TBC and therefore increased thermal conductivity. If sufficiently fine, the precipitates also serve to pin the grains and pore boundaries of the TBC, the effect of which is to reduce the tendency for the microstructure of the TBC to sinter, coarsen and undergo pore redistribution, which also increase thermal conductivity of the TBC 26.