Abstract <p>The physical and mathematical simulation of the high-speed twisting was conducted under temperature-deformation parameters similar to those of friction stir welding. The tests were carried out at elevated temperatures, with various degrees and speeds of deformation. A qualitative and quantitative analysis of the investigated alloy was performed using optical microscopy, which involved determining the grain size in different zones. A regularity was established regarding the change in grain size based on the temperature-deformation parameters of high-speed twisting. The critical temperature-deformation parameters for the onset of dynamic recrystallization were identified.</p>