摘要:
A sacrificial and erosion-resistant turbine compressor airfoil includes a turbine compressor airfoil having a modified airfoil surface. The airfoil surface has an airfoil coating that includes a sacrificial coating comprising a layer of Al, Cr, Zn, an Ni—Al alloy, an Al—Si alloy, an Al-based alloy, a Cr-based alloy or a Zn-based alloy, an Al polymer composite, or a combination thereof, or a layer of a conductive undercoat and an overcoat of an inorganic matrix binder having a plurality of ceramic particles and conductive particles embedded therein disposed on the undercoat. The airfoil coating also includes an sacrificial coating, wherein one of the sacrificial coating or the erosion-resistant coating is disposed on the airfoil surface and the other of the corrosion-resistant coating or the erosion-resistant coating is disposed on the respective one, and wherein the sacrificial coating is more anodic than the airfoil surface or the erosion-resistant coating.
摘要:
A coating system and process capable of providing erosion and corrosion-resistance to a component, particularly a steel compressor blade of an industrial gas turbine. The coating system includes a metallic sacrificial undercoat on a surface of the component substrate, and a ceramic topcoat deposited by thermal spray on the undercoat. The undercoat contains a metal or metal alloy that is more active in the galvanic series than iron, and electrically contacts the surface of the substrate. The ceramic topcoat consists essentially of a ceramic material chosen from the group consisting of mixtures of alumina and titania, mixtures of chromia and silica, mixtures of chromia and titania, mixtures of chromia, silica, and titania, and mixtures of zirconia, titania, and yttria.
摘要:
A corrosion inhibitor composition for a fuel, comprising a plurality of nanoparticles formed of an inorganic composition having an average longest dimension of 1 nanometer to 100 nanometers, wherein the inorganic active composition is insoluble in the fuel and is adapted to react with a corrosion causing contaminant.
摘要:
A corrosion inhibitor composition for a fuel, comprising a plurality of nanoparticles formed of an inorganic composition having an average longest dimension of 1 nanometer to 100 nanometers, wherein the inorganic active composition is insoluble in the fuel and is adapted to react with a corrosion causing contaminant.
摘要:
A process is provided for forming shaped air holes, such as for use in turbine blades. Aspects of the disclosure relate to forming shaped portions of air holes using a short pulse laser, forming a metered hole corresponding to each shaped portion, and separately finishing the shaped portion using a short-pulse laser. In other embodiments, the order of these operations may be varied, such as to form the shaped portions and to finish the shaped portions using the short-pulse laser prior to forming the corresponding metered holes.
摘要:
A process and system are provided for forming shaped air holes, such as for use in turbine blades. Aspects of the disclosure relate to forming shaped portions of air holes using a short pulse laser, forming a metered hole corresponding to each shaped portion, and separately finishing the shaped portion using a short-pulse laser. In other embodiments, the order of these operations may be varied, such as to form the shaped portions and to finish the shaped portions using the short-pulse laser prior to forming the corresponding metered holes.
摘要:
A bi-layer bond coating for use on metal alloy components exposed to hostile thermal and chemical environment, such as a gas turbine engine, and the method for applying such coatings. The preferred coatings include a bi-layer bond coat applied to the metal substrate using high velocity oxy-fuel (HVOF) thermal spraying. Bi-layer bond coatings in accordance with the invention consist of a dense first inner layer (such as iron, nickel or cobalt-based alloys) that provides oxidation protection to the metal substrate, and a second outer layer having controlled porosity that tends to promote roughness, mechanical compliance, and promotes adherence of the thermal barrier coating (TBC). Preferably, the outer, less dense layer of the bi-layer bond coat is formed from a mixture of metallic powder and polyester to adjust and control the porosity, but without sacrificing mechanical compliance.
摘要:
A titanium aluminide application process and article with a titanium aluminide surface are disclosed. The process includes cold spraying titanium aluminide onto an article within a treatment region to form a titanium aluminide surface. The titanium aluminide surface includes a refined gamma/alpha2 structure and/or the titanium aluminide is cold sprayed from a solid feedstock of a pre-alloyed powder.
摘要:
A cobalt-nickel base alloy is disclosed. The alloy includes, in weight percent: greater than about 4 % of Al, about 10 to about 20 % of W, about 10 to about 40 % Ni, about 5 to 20 % Cr and the balance Co and incidental impurities. The alloy has a microstructure that is substantially free of a CoAl phase having a B2 crystal structure and configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment. A method of making an article of the alloy includes: selecting the alloy; forming an article from the alloy; solution-treating the alloy; and aging the alloy to form an alloy microstructure that is substantially free of a CoAl phase having a B2 crystal structure, wherein the alloy is configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment.
摘要:
A precipitation-hardened stainless steel alloy comprises, by weight: about 14.0 to about 16.0 percent chromium; about 6.0 to about 8.0 percent nickel; about 1.25 to about 1.75 percent copper; greater than about 1.5 to about 2.0 percent molybdenum; about 0.001 to about 0.025 percent carbon; niobium in an amount greater than about twenty times that of carbon; and the balance iron and incidental impurities. The alloy has an aged microstructure and an ultimate tensile strength of at least about 1100 MPa and a Charpy V-notch toughness of at least about 69 J. In one embodiment, the aged microstructure includes martensite and not more than about 10% reverted austenite. In another embodiment, the alloy includes substantially all martensite and substantially no reverted austenite. The alloy is useful for making turbine airfoils.