Layered assemblies for superalloy article repair
Methods of superalloy article repair are provided. In some embodiments, a method for repairing a nickel-based superalloy article comprises providing a layered assembly over a damaged region of the nickel-based superalloy article, the layered assembly comprising a nickel-based superalloy preform, an infiltration alloy preform and a melting point depressant component. The layered assembly is heated to form a nickel-based filler alloy metallurgically bonded to the damaged region, wherein primary carbide and secondary carbide phases are present in the nickel-based filler alloy in a combined amount of 0.5 to 10 vol. %.
1. A nickel-based superalloy article comprising:
a damaged region; and
a nickel-based filler alloy metallurgically bonded to the damaged region, the nickel-based filler alloy having composition of 8-15 wt. % chromium, 7-14 wt. % cobalt, 0.1-5 wt. % molybdenum, 5-11 wt % tungsten, 1-5 wt. % tantalum, 2-7 wt. % aluminum, 0.1-1.5 wt % boron, 0.1-5 wt % titanium, 0-2 wt % hafnium, 0.05-1 wt. % carbon, 0-0.5 wt. % yttrium and the balance nickel, wherein primary carbide and secondary carbide phases are present in the nickel-based filler alloy in a combined amount of 0.5 to 10 vol. %.
2. The nickel-based superalloy article of claim 1 , wherein the nickel-based filler alloy is of composition 10-12 wt. % chromium, 9-11 wt. % cobalt, 0.3-0.5 wt. % molybdenum, 5-7 wt % tungsten, 2-3 wt. % tantalum, 4-5 wt. % aluminum, 0.7-1 wt % boron, 0.5-0.8 wt % titanium, 0.6-1 wt % hafnium, 0.05-0.2 wt. % carbon, 0-0.5 wt. % yttrium and the balance nickel.
3. The nickel-based superalloy article of claim 1 , wherein secondary M 23 C 6 carbides are present in an amount of 1 to 4 vol. % of the nickel-based filler alloy.
4. The nickel-based superalloy article of claim 1 , wherein secondary M 23 C 6 carbides are present in an amount of 2 to 3 vol. % of the nickel-based filler alloy.
5. The nickel-based superalloy article of claim 3 , wherein M is one or more transition metals selected from the group consisting of chromium, molybdenum and tungsten.
6. The nickel-based superalloy article of claim 3 , wherein primary MeC carbides are present an amount of 0.5 to 5 vol. % of the nickel-based filler alloy.
7. The nickel-based superalloy article of claim 6 , wherein Me is selected form the group consisting of titanium, tantalum and hafnium.
8. The nickel-based superalloy article of claim 6 , wherein the nickel-based filler alloy further comprises a C 2 Cr 3 phase.
9. The nickel-based superalloy article of claim 1 , wherein tensile strength of the nickel-based filler alloy is 50-70% of the nickel-based superalloy article tensile strength according to ASTM E21—Standard Test Methods for Elevated Temperature Tension Testing of Metallic Materials.
10. The nickel-based superalloy article of claim 9 , wherein nickel-based filler alloy has at least 2 percent elongation according to ASTM E21—Standard Test Methods for Elevated Temperature Tension Testing of Metallic Materials.
11. The nickel-based superalloy article of claim 10 , wherein nickel-based filler alloy has up to 10 percent elongation according to ASTM E21—Standard Test Methods for Elevated Temperature Tension Testing of Metallic Materials.
12. The nickel-based superalloy article of claim 1 , wherein the damaged region comprises a hole in a surface of the nickel-based superalloy article.