Microstructure simulation of GH4066 turbine disc in forging process

Abstract

GH4066 is a new type of wrought superalloy used to fabricate full-size high-pressure turbine disc for aero-engine with a diameter of more than 600 mm and a working temperature above 700°Cby advanced casting-forging technology. In this paper, the material models including the constitutive relation model, the peak strain and critical strain model, the dynamic recrystallization and grain size model are all obtained based on the flow stress measured by thermo-physical simulation test. And these microstructure evolution models are embedded into the finite element software Deform to simulate the hot forging process of GH4066 turbine disc. As a result, the microstructure changes in different regions on the turbine disc during the hot forging process were calculated, and the dynamic recrystallization and grain growth were analyzed. Thus, the microstructure evolution law of the turbine disc during hot forging process was obtained, which can provide a reference for the forging process optimization and microstructure control, and it is of great significance to the popularization and application of this new material.