Abstract: A valve for use in an internal combustion engine is disclosed. The valve includes a stem friction welded to a head portion. The head portion is cast from a single crystal metal using a casting process that creates little or no grain boundaries. The single crystal metal can be a nickel based superalloys such as CMSX-4, CMSX 3, Rene N5, and Rene N6. By having little or no grain boundaries, defects that occur in other types of casting material, such as large numbers of grain boundaries can be minimized. This allows the head portion and particularly the combustion face to withstand an operating temperature in the combustion chamber in excess of 850° C.

Abstract: A valve for use in an internal combustion engine is disclosed. The valve includes a stem friction welded to a head portion. The head portion is cast from a single crystal metal using a casting process that creates little or no grain boundaries. The single crystal metal can be a nickel based superalloys such as CMSX-4, CMSX 3, Rene N5, and Rene N6. By having little or no grain boundaries, defects that occur in other types of casting material, such as large numbers of grain boundaries can be minimized. This allows the head portion and particularly the combustion face to withstand an operating temperature in the combustion chamber in excess of 850° C.

Abstract: A valve for use in an internal combustion engine is disclosed. The valve includes a stem connected to a fillet disposed between the stem and a seat face. A thermal spray technique, such as a high velocity oxy fuel coating spray (HVOF) is applied to the seat face. A nitriding treatment that includes a nitrogen source, which may or may not contain carbon, and heat may be applied after the HVOF spray. The heat allows the nitrogen and/or carbon to penetrate the HVOF layer and the seat face to form a compound zone. The compound zone enhances the wear resistance of the surface during engine operation.

Abstract: A nickel-base braze material suitable for closing holes in a high temperature component, such as a tip cap hole in a turbine blade. The braze material comprises first and second filler materials and a binder. The first filler material comprises particles of a first alloy, and the second filler material comprises particles of at least a second alloy having a lower melting temperature than the first alloy. The second alloy consists essentially of, by weight, about 8 to about 23 percent chromium, about 4 to about 18 percent cobalt, about 1.5 to about 6.0 percent tantalum, about 1.0 to about 6.0 percent aluminum, about 0.3 to about 1.5 percent boron, about 2.0 to about 6.0 percent silicon, up to 0.2 percent carbon, the balance being nickel and incidental impurities.