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Nickel-based superalloys are used in load-bearing structures requiring the highest homologous temperature of any common alloy system (Tm = 0.9, or 90% of their melting point). Among the most demanding applications for a structural material are those in the hot sections of turbine engines (e.g. turbine blade). They comprise over 50% of the ...
Modern turbine blades often use nickel-based superalloys that incorporate chromium, cobalt, and rhenium. [ 14 ] [ 18 ] Aside from alloy improvements, a major breakthrough was the development of directional solidification (DS) and single crystal (SC) production methods.
The nickel-based superalloys are well known for their intensive use in the industrial field especially the aeronautical and the aerospace industry due to their superior mechanical and corrosion properties at high temperatures. [8] An example of the use of the nickel-based superalloys in the industrial field would be turbine blades.
[4] [5] Nimonic 80a was used for the turbine blades on the Rolls-Royce Nene and de Havilland Ghost, Nimonic 90 on the Bristol Proteus, and Nimonic 105 on the Rolls-Royce Spey aviation gas turbines. Nimonic 263 was used in the combustion chambers of the Rolls-Royce/Snecma Olympus 593 used on the Concorde supersonic airliner. The heads of the ...
Alloys of nickel are the most common but includes iron aluminum alloys. [1] Applications include high temperature turbine blades and heat exchanger tubing, [2] while steels are used in nuclear applications. [3] ODS materials are used on spacecraft to protect the vehicle, especially during re-entry. Noble metal ODS alloys, for example, platinum ...
The nickel-based superalloys have improved creep strength with the addition of rhenium. The alloys normally contain 3% or 6% of rhenium. [ 57 ] Second-generation alloys contain 3%; these alloys were used in the engines for the F-15 and F-16 , whereas the newer single-crystal third-generation alloys contain 6% of rhenium; they are used in the F ...
Waspaloy is an age-hardenable, nickel-based superalloy with excellent strength properties through temperatures of roughly 980°C (1800°F). Other characteristics of Waspaloy include good corrosion resistance, as well as being relatively impervious to oxidation making it well suited for service in extreme environments.
Directional solidification is the preferred technique for casting high temperature nickel-based superalloys that are used in turbine engines of aircraft. Some microstructural problems such as coarse dendritic structure, long dendrite side branches, and porosity hinder the full potential of single crystal ni-based alloys. [6]