A γ″ precipitate-evolution-informed CPFEM describing mechanical behavior of GH4169 under electropulsing-assisted aging

Electropulsing-assisted aging (EAA) has emerged as a promising route for modifying the microstructure and mechanical properties of thin-walled superalloy components. However, the relationships among current parameters, γ″ precipitate evolution, and mechanical response remain insufficiently understood. In this study, EAA and uniaxial tensile tests were performed on GH4169 sheet specimens. An electromigration-informed precipitate evolution model was established based on TEM observations, and a crystal plasticity finite element model (CPFEM) incorporating precipitate shearing and Orowan bypassing resistances was then developed, with a multi-phase representative volume element (RVE) model. The constitutive framework was implemented in Abaqus using VUMAT. Parameters were identified via inverse FE calibration with the particle swarm optimization (PSO) method. The results indicate a temperature-driven enhancement of electromigration during the γ″ coarsening process and a strengthening mechanism based on multi-mode shearing and bypassing. These findings provide a mechanistic basis for describing the EAA-modified tensile response of GH4169 and offer useful insight for future EAA-assisted processing of thin-walled superalloy components.