摘要:
A slurry coating composition is described, which is very useful for enriching the surface region of a metal-based substrate with aluminum. The composition includes colloidal silica and particles of an aluminum-based powder, and is substantially free of hexavalent chromium. The slurry may include colloidal silica and an alloy of aluminum and silicon. Alternatively, the slurry includes colloidal silica, aluminum or aluminum-silicon, and an organic stabilizer such as glycerol. The slurry exhibits good thermal and chemical stability for extended periods of time, making it very useful for industrial applications. Related methods and articles are also described.
摘要:
A method for removing a chromide coating from the surface of a substrate is described. The coating is treated with a composition which includes an acid having the formula HxAF6, where “A” can be Si, Ge, Ti, Zr, Al, or Ga; and x is 1–6. An exemplary acid is hexafluorosilicic acid. The composition may also include a second acid, such as phosphoric acid or nitric acid. In some instances, a third acid is employed, such as hydrochloric acid. A related repair method for replacing a worn or damaged chromide coating is described. The coating is often applied to portions of turbine engine components made from superalloy materials.
摘要翻译:描述了从基板的表面去除铬化物涂层的方法。 涂层用包括具有下式的酸组成的组合物处理:其中“A”可以是Si,Ge,Ti,Zr,Al或 Ga x为1-6。 示例性的酸是六氟硅酸。 组合物还可以包括第二种酸,如磷酸或硝酸。 在一些情况下,使用第三种酸,例如盐酸。 描述了用于替换磨损或损坏的铬酸盐涂层的相关修复方法。 涂层通常用于由超级合金材料制成的涡轮发动机部件的部分。
摘要:
A reactor has an inner surface accessible to the hydrocarbon and comprising a sintered product of at least one of cerium oxide, zinc oxide, tin oxide, zirconium oxide, boehmite and silicon dioxide, and a perovskite material of formula AaBbCcDdO3-δ. 0
摘要:
A method for cracking hydrocarbon, comprises: providing steam and hydrocarbon; and feeding steam and hydrocarbon into a reactor accessible to hydrocarbon and comprising a perovskite material of formula AaBbCcDdO3-δ, wherein 0
摘要:
The present invention provides a method of protecting refinery equipment, the method comprising: (a) applying an uncured organic coating comprising a curable epoxy phenol novolac resin and a curing agent comprising a vicinal primary diamine moiety to a surface of refinery equipment susceptible to corrosion and/or wear; and (b) curing the uncured coating to form a cured coating having a viscosity of at least 2,000,000 centipoise; wherein the uncured organic coating has a viscosity of less than 500,000 centipoise, and wherein the uncured coating is substantially free of components comprising secondary and tertiary amine groups, and wherein the uncured coating is characterized by a latent viscosity of at least 2,000,000 when cured for 1 hour at 50° C.
摘要:
Methods of fabricating coated components using multiple types of fillers are provided. One method comprises forming one or more grooves in an outer surface of a substrate. Each groove has a base and extends at least partially along the outer surface. A sacrificial filler is deposited within the groove, a second filler is deposited over the sacrificial filler, and a coating is disposed over at least a portion of the outer surface and over the second filler. The method further includes removing the sacrificial filler and at least partially removing the second filler from the groove(s), to define one or more channels for cooling the component.
摘要:
A casting process and apparatus for producing directionally-solidified castings, and castings produced therewith. The process entails applying a facecoat slurry to a surface within a mold cavity to form a continuous solid facecoat on the surface, introducing a molten metal alloy into the mold cavity so that the molten metal alloy contacts the facecoat, and then immersing the mold in a liquid coolant to cool and solidify the molten metal alloy and form a casting of the metal alloy, during which an oxide layer forms on the casting surface. The facecoat is sufficiently adherent to the oxide layer such that at least a portion of the facecoat detaches from the mold surface and remains tightly adhered to the casting surface in the event the casting contracts during cooling. The facecoat contains at least 60 weight percent of a first phase of yttria, and the balance of the facecoat is a binder phase of an inorganic material.
摘要:
The present disclosure is directed to the use and manufacture of cooling features within a component used in a hot gas path, such as within a turbine. In one embodiment, channels are formed within an external surface of the component and filled with a removable material. The external surface and channels may then be coated with one or more layers, such as a structural layer and/or top coat. The removable material may then be removed to leave the channels free of the removable material.
摘要:
The present invention provides a method for preparing an electroless nickel coating composition that includes (a) coating a substrate with an electroless nickel coating to provide a coated substrate; and (b) subjecting the coated substrate to a heating protocol comprising heating to a temperature in a range from about 550° C. to about 700° C. for a period of from about 7 to about 30 hours. An article made from the method is also provided.
摘要:
A method for removing sand particles from a substrate is described. The method includes the step of treating the substrate with an acid solution comprising HxAF6, wherein A is selected from the group consisting of Si, Ge, Ti, Zr, Al, and Ga; and wherein HxAF6 is present at a concentration in the range from about 5 weight percent to about 40 weight percent.