A Discontinuous Dynamic Recrystallization Model for Predicting Grain Features during Friction Stir Welding and Processing

Friction Stir Welding (FSW) and Processing leads to severe plastic deformation in materials. The large amount of strain combined with high temperature of processing results in Dynamic Recrystallization and Grain Growth. The final properties of the processed materials are dependent of the recrystallized grain structure. Here we present an analytical framework based on Discontinuous Dynamic Recrystallization (DDRX) principles considering plastic deformation, nucleation, and growth. The present model is coupled with the heat transfer and material flow model for FSW, wherein the temperature and strain rates are computed. The computed strain rate and temperatures are utilized as input parameters in the present model. The Kernel Density Estimation is used to compute the grain size distribution during the process. The computed grain size distribution is compared with the experimentally measured grain size in a sample undergone same processing conditions.