pThe present invention relates to a nickel-base ³/³' superalloy with a unique blend of at most moderate cost, high oxidation resistance, high hot corrosion resistance, moderate strengthening, adequate alloy stability, and comparatively good weldability. The said alloy comprises: Up to 20 wt% of the sum of Co and Fe, between 17 and 21 wt% Cr, between 0.5 and 3 wt% of the sum of Mo and W, at most 2 wt% Mo, between 4.8 and 6 wt% A1, between 1.5 and 5 wt% Ta, between 0.01 and 0.2 wt% of the sum of C and B, between 0.01 and 0.2 wt% Zr, between 0.05 and 1.5 wt% Hf, between 0.05 and 1.0 wt% Si, and between 0.01 and 0.5 wt% of the sum of rare earths such as Sc, Y, the actinides and the lanthanides, such that at least two of these rare earths are present in the alloy, and no more than 0.3 wt% of any of these rare earths. It further relates to its use in hot components such as, but not restricted to, blades, vanes, heat shields, sealings and combustor parts in gas turbines. It further relates to its use as filler alloy for repair welding and/or cladding of such hot components. It further relates to its use as protective coating and/or bond coat in a TBC system on such hot components. It further relates to its dual use as coating and/or bond coat, and, for repair and/or cladding on such hot components. It further relates to its use as intermediate layer between the base alloy and another coating and/or bond coat on such hot components. It further relates to its use in polycrystalline, directionally solidified or single crystal form in such components. It further relates to its production by processes such as, but not restricted to, precision casting, laser welding/cladding, hot box welding, laser sintering, cold spraying, explosion welding and vacuum plasma spraying. It further relates to its production by low S processing. It further relates to its use as part of material systems as exemplified above produced by low S processing./p[EP2248923A1]
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