Prediction of microstructure in machined deformation layer considering the effect of γ′ precipitates of FGH96 through a FEM-CA coupling method

The complex non-uniform deformation field in the cutting process induces microstructural evolution, leading to changes in mechanical properties, which has attracted increasing attention. This fundamental research aims to reveal the grain refinement process of the machined deformation layer of powder metallurgy superalloy. The static pinning effect of γ′ precipitates of the nickel PM superalloy FGH96 was considered. A predictive model was established for the evolution of continuous and discontinuous dynamic recrystallization grains during the cutting process. Finite element–cellular automaton coupling was employed to predict microstructural evolution in the machined deformation layer. Model validity was confirmed by comparison with experimental results, and the microstructural characteristics were analyzed. This study contributes to a further understanding of microstructure evolution during the machining of nickel powder metallurgy superalloys and provides a theoretical basis for guiding process optimization.