Abstract: A primary layer of an MCrAlY-type material is first applied to a metal-based substrate by a vacuum plasma spray (VPS) technique, or by HVOF. A secondary layer is then also applied by VPS or HVOF. It is formed of the following alloy (in atom percent): 0 to about 25 cobalt; about 7 to 25 chromium; about 18 to about 55 aluminum; 0 to about 1 yttrium; and 0 to about 2 silicon, with the balance comprising nickel. The applied layers are then heat-treated. Related articles are also described.

Abstract: A solid-solution strengthened superalloy weld composition, includes: about 10 to about 15 wt % Co; about 18 to about 22 wt % Cr; about 0.5 to about 1.3 wt % Al; about 3.5 to about 4.5 wt % Ta; about 1 to about 2 wt % Mo; about 13.5 to about 17.0 wt % W, up to about 0.08 wt % C; up to about 0.06 wt % Zr; up to about 0.015 wt % B; about 0.4 to about 1.2 wt % Mn; about 0.1 to about 0.3 wt % Si; and balance Ni.

Abstract: A solid-solution strengthened superalloy weld composition, includes: about 0 to about 10 wt % Co; about 18 to about 22 wt % Cr; about 0.2 to about 0.7 wt % Al; about 15 to about 28 wt % of the sum of refractory elements; up to about 0.09 wt % C; up to about 0.06 wt % Zr; up to about 0.015 wt % B; about 0.4 to about 1.2 wt % Mn; about 0.2 to about 0.45 wt % Si; and balance Ni.

Abstract: A combustor/transition piece for a gas turbine including a double walled structure having a plurality of cooling channels, both axially and, in some cases, circumferential cross-flow passages positioned between the structure's inner member and the outer member to provide cooling air thereto, are formed in the area between the inner member of the combustor and the outer member thereof. The passages preferably extend both axially and circumferentially with respect to the direction of flow through the combustor/transition piece. The axial passages extend completely from one end to the other and the circumferential passages extend around the circumference of the combustor/transition piece. The addition of a circumferential cross-flow passage connecting axial flow coolant passages in double wall turbine components can prevent combustor/transition piece part failure due to axial passage inlet blockage without affecting normal, unblocked cooling.

Abstract: A method is disclosed to deposit aluminum coatings on high temperature superalloys for corrosion, oxidation, and erosion protection using low temperature chemical vapor deposition and an organometallic halide precursor, specifically an aluminum alkyl halide. The process is adapted to protective coatings for turbine parts having internal passages. Due to the lower temperatures used during chemical vapor deposition, a broad range of substrate materials can be utilized. The precursor vapors clean the substrate surfaces by removing native oxides while simultaneously depositing aluminum.