Flash Sintering of Bimetallic Assemblies for Turbine Disks in Next‐Generation Jet Engines.

René 77 and another advanced powder metallurgy nickel‐based superalloy are flash‐sintered and joined to produce a dual‐alloy assembly. This innovative process allows for the sintering of powders to achieve high relative densities or the formation of solid joints in a shorter time than is feasible with conventional diffusion bonding techniques. Examination of the microstructure after heat treatments reveals that diffusion and recrystallization phenomena can modulate the transition zone. The creep properties of both alloys, evaluated using stress relaxation tests, do not seem to differ by more than an order of magnitude, while the higher thermal stability of René 77 compared to Alloy B at 800 °C tips the scales. In tension, base materials show very high properties, while bimetallic specimens exhibit at least higher properties than René 77. However, failure occurs at the bond at high temperatures due to the formation of an oxide film during the bonding process. These encouraging results illustrate the potential and constraints of the flash‐sintering process for producing dissimilar assemblies, which may enhance the properties of next‐generation aero‐engine turbine disks. [ABSTRACT FROM AUTHOR]