Integrated modeling for the manufacture of aerospace discs: Grain structure evolution

Process models of the various stages of gas turbine disc manufacture have been integrated to simulate the grain structure evolution of a nickel-based superalloy throughout the manufacturing route. The production of these critical structural components requires several distinct processing stages: vacuum induction melting, vacuum arc remelting, homogenization heat treatment, cogging, forging, final heat treatment, and machining. The microstructure, and hence properties, change significantly during these consecutive manufacturing stages due to the various thermal and thermo-mechanical treatments. Although separate models have previously been applied to the different processing stages, this article describes how these models can be integrated to track the microstructure of the part from secondary melting through to the final forging.