A method of polishing a metallic workpiece includes: mounting the workpiece in a hopper; loading the hopper with a polishing media comprising, by weight percent, more than 98% metallic chips, less than 2% liquid, and less than 0.05% abrasive; and oscillating the hopper for a run time, thereby generating a flow of the polishing media over the workpiece, until a predetermined surface finish is achieved on the workpiece.

During a material removal method, a component is received that includes a component body and a coating on the component body. The component body includes metallic first material. The coating includes second material that is different from the first material. A solution is received that includes nitric acid and hydrogen peroxide. At least a portion of the coating is subjected to the solution in order to remove at least some of the second material from the component.

A coating system for a surface of a superalloy component is provided. The coating system includes a MCrAlY coating on the surface of the superalloy component, where M is Ni, Fe, Co, or a combination thereof. The MCrAlY coating generally has a higher chromium content than the superalloy component. The MCrAlY coating also includes a platinum-group metal aluminide diffusion layer. The MCrAlY coating includes Re, Ta, or a mixture thereof. Methods are also provided for forming a coating system on a surface of a superalloy component.

A method includes providing a powdered high entropy alloy and forming the powdered high entropy alloy into a seal body with a heat source. The seal body extends between a leading edge and a trailing edge and includes a first component contact surface adjacent the leading edge and a second component contact surface adjacent the trailing edge. The seal body is operable at temperatures in excess of 700° C.

A rotor disk is provided. The rotor disk may comprise a disk lug and a trench. The disk lug may be fixed to a distal surface of the rotor disk. The trench may be disposed on a surface of the disk lug. The trench may extend radially inwards from a distal surface of the disk lug. The trench may be configured to at least partially define a flow path by which cooling air may reach a distal surface of the disk lug in order to provide disk lug cooling.

Method and apparatus are provided for electroplating a surface area of an internal wall defining a cooling cavity present in a gas turbine engine component.

The invention relates to a nickel-based superalloy comprising, in percentages by mass, 4.0 to 5.5% rhenium, 1.0 to 3.0 ruthenium, 2.0 to 14.0% cobalt, 0.3 to 1.0% molybdenum, 3.0 to 5.0% chromium, 2.5 to 4.0% tungsten, 4.5 to 6.5% aluminum, 0.50 to 1.50% titanium, 8.0 to 9.0% tantalum, 0.15 to 0.30% hafnium, 0.05 to 0.15% silicon, the balance being nickel and unavoidable impurities.

The invention also relates to a single-crystal blade (20A, 20B) comprising such an alloy and a turbomachine (10) comprising such a blade (20A, 20B).

A coated article includes a substrate and an MCrAlY coating supported on the substrate. The M includes at least one of nickel, cobalt, and iron, Cr is chromium, Al is aluminum, and Y is yttrium. The composition of the MCrAlY coating varies in an amount of at least one of Cr, Al, and Y by location on the substrate with respect to localized property requirements. In one example, the coated article is an article of a gas turbine engine.

A blade outer airseal has a body comprising: an inner diameter (ID) surface; an outer diameter (OD) surface; a leading end; and a trailing end. The airseal body has a metallic substrate and a coating system atop the substrate along at least a portion of the inner diameter surface. At least over a first area of the inner diameter surface, the coating system comprises an abradable layer comprising a metallic matrix and a solid lubricant; and the metallic matrix comprises, by weight, ≧35% nickel, 12.0-20.0% cobalt, 5.0-15.0% aluminum, and 5.0-15.0% chromium.

A blade outer airseal has a body comprising: an inner diameter (ID) surface; an outer diameter (OD) surface; a leading end; and a trailing end. The airseal body has a metallic substrate and a coating system atop the substrate along at least a portion of the inner diameter surface. At least over a first area of the inner diameter surface, the coating system comprises an abradable layer system comprising a plurality of layers including a relatively erosion-resistant first layer atop a relatively abradable second layer.