A method of applying a protective coating to an article comprises the steps of a) depositing aluminum in a surface region of an article, and b) depositing chromium is the surface region of the article subsequent to step a), whereby at least a portion of the chromium replaces at least a portion of the aluminum. Another method and an article are also disclosed.

A coated metallic substrate is provided, including, at least; one layer of oxides, such layer being directly topped by an intermediate coating layer comprising Fe, Ni, Cr and Ti wherein the amount of Ti is above or equal to 5 wt. % and wherein the following equation is satisfied: 8 wt. %<Cr+Ti<40 wt. %, the balance being Fe and Ni, such intermediate coating layer being directly topped by a coating layer being an anticorrosion metallic coating.

A method of applying a protective coating to an article comprises the steps of a) depositing aluminum in a surface region of an article, and b) depositing chromium is the surface region of the article subsequent to step a), whereby at least a portion of the chromium replaces at least a portion of the aluminum. Another method and an article are also disclosed.

The present invention provides a Cr-rich cathodic arc coating, an article in turbine blade coated with the chromizing over cathodic arc coating, and a method to produce the coating thereof. The Cr-rich cathodic arc coating in the present invention comprises a cathodic arc coating and a diffusion coating deposited atop the cathodic arc coating to enforce hot corrosion resistance. The hardware coated with the chromizing over cathodic arc coating in the present invention is reinforced with superior-hot corrosion resistance. The present invention further provides a novel method for producing the chromizing over cathodic arc coating by re-sequencing coating deposition order. The method in the present invention is efficient and cost-reducing by eliminating some operations, e.g., DHT and peening, between the cathodic arc coating and the diffusion coating. The hot corrosion resistance in the present invention results from the high Cr content in the surface of the coating.

A hydrocarbon fluid containment article having a wall with a surface that is wetted by hydrocarbon fluid. The surface includes an anti-coking coating. The anti-coking coating includes a copper salt, a silver salt, or a combination thereof. A gas turbine engine component including a wall having a first surface and an anti-coking coating on the first surface of the wall that is wetted by hydrocarbon fluid. The anti-coking coating including a copper salt, a silver salt, or a combination thereof that prevents the formation of gum or coke on a surface thereon. Methods for reducing the deposition of thermal decomposition products on a wall of an article are also provided.

Methods of enhancing the corrosion resistance of an oxidizable material exposed to a supercritical fluid is disclosed One method includes placing a surface layer on an oxidizable material, and choosing a buffered supercritical fluid containing a reducing agent with the composition of the buffered supercritical fluid containing the reducing agent chosen to avoid the corrosion of the surface layer or reduce the rate of corrosion of the surface layer and avoid the corrosion of the oxidizable material or reduce the rate of corrosion of the oxidizable material at a temperature above the supercritical temperature and supercritical pressure of the supercritical fluid.

A method of applying a protective coating to an article comprises the steps of a) depositing aluminum in a surface region of an article, and b) depositing chromium is the surface region of the article subsequent to step a), whereby at least a portion of the chromium replaces at least a portion of the aluminum. Another method and an article are also disclosed.

Molybdenum is alloyed into stainless steel surface by electro-spark deposition technique. Shielding gas is used during electro-spark deposition process to minimize the oxidation of materials. Control of electro-spark voltage, frequency, capacitance, time can determine the alloying depth of Molybdenum. The alloyed surface thickness varies from 5 m to 80 m depending on the electro-spark deposition parameters. The alloyed surface comprises, by weight, 15 to 40% of Molybdenum, 8 to 22% of Cr, 0-15% of other alloy elements and impurities. The molybdenum alloyed stainless steel surface exhibits improvement in micro-hardness, wear resistance, and especially corrosion resistance in sodium chloride solutions. Thus, the present invention would be utilized in marine and handling of brines application, as well as in other applications which better corrosion resistance of stainless steel is desired.

The present invention provides a Cr-rich cathodic arc coating, an article in turbine blade coated with the chromizing over cathodic arc coating, and a method to produce the coating thereof. The Cr-rich cathodic arc coating in the present invention comprises a cathodic arc coating and a diffusion coating deposited atop the cathodic arc coating to enforce hot corrosion resistance. The hardware coated with the chromizing over cathodic arc coating in the present invention is reinforced with superior-hot corrosion resistance. The present invention further provides a novel method for producing the chromizing over cathodic arc coating by re-sequencing coating deposition order. The method in the present invention is efficient and cost-reducing by eliminating some operations, e.g., DHT and peening, between the cathodic arc coating and the diffusion coating. The hot corrosion resistance in the present invention results from the high Cr content in the surface of the coating.

An apparatus includes a ceramic matrix composite (CMC) component and an interface coating on the CMC component, wherein the interface coating includes a layer of at least one of the following compositions: 40-50 wt % Nb, 28-42 wt % Al, 4-15 wt % Cr, 1-2 wt % Si; 90-92 wt % Mo, 4-5 wt % Si, 4-5 wt % B; or 60-80 wt % V, 20-30 wt % Cr, 2-15 wt % Ti.