Study of the microstructure of laser-assisted burnishing GH4169

The microstructure of nickel-based alloys (GH4169) which including grain gradients and grain boundary structures is a key factor influencing the mechanical properties and service life during processing of the material during processing. It is an in-depth analysis that required to enhance the mechanical properties of material. By introducing in-situ thermal assistance to the conventional finishing burnishing process to reduce the deformation resistance of material, precise control over the microstructure and properties of the metal surface can be achieved. In this study, a cellular automaton (CA) model is established to construct a simulation framework which comprehensively accounts for strain rate, temperature fields, and dynamic recrystallization (DRX) kinetics for the microstructural evolution of GH4169 that is applied to the conventional burnishing and laser-assisted burnishing processes. By comparing grain size, grain boundary distribution and other factors under different processes, this study reveals the regulatory mechanisms of laser energy input on the microstructure within the plastic deformation zone. The results indicate that laser-assisted burnishing promotes dynamic recrystallization through thermo-mechanical coupling effects. Experimental validation of the predicted grain refinement layer showed prediction errors of less than 5%.