Multi-scale modeling and simulation for multi-pass processing of Ta-2.5 W alloy

Multi-pass deformation and annealing process is commonly utilized to prepare billets with homogeneous fine microstructure. Characterizing the deformation and microstructural evolution is not easy due to the complex process. This study proposed a multi-scale modeling and simulation method for the multi-pass processing and it was validated by experiments. Firstly, an integrate multi-scale model involving strain hardening and static softening equations was developed based on multi-pass cold deformation and annealing tests of Ta-2.5 W alloy. Of note, the model captures both deformation behavior and static softening and the model equations of each pass were integrated into a unified manner. Then, multi-scale simulation including finite element (FE) and cellular automatic (CA) methods was coupled with the developed model for static recrystallization (SRX) analysis. FE analysis was firstly performed to predict the distributions of strain, dislocation density as well as SRX. Simultaneously, the predicted data was used for generation of the initial conditions for mesoscopic model. Finally, a CA method was applied for further analysis on recrystallization nucleation and grain growth. The modeling and simulation method is examined by multi-pass cold deformation and annealing test and a reasonable consistency is obtained between experimental and predicted results.