Incremental formulation for the prediction of microstructural change in multi-pass hot forming

A new mathematical formulation for static microstructural changes in hot fo rming is proposed. This formulation can be easily coupled with incremental model for dynamic microstructural changes as it is formulated in an increme ntal form using the dislocation density as a representative variable with I :he simplification of recrystallized structure. Coupling incremental formul ations for dynamic and static microstructural changes, microstructural chan ges under multi-pass hot forming are computed and discussed. As these formu lations are formulated in an incremental form, we will be able to predict m icrostructural evolution including partial dynamic/static recrystallization caused by any deformation history and temperature history computed by FEM and/or FDM.