Finite element simulation of hot die forming and optimization design of preform for a blade with large-angle crankle

The hot die forming of blades with large-angle crankle is simulated with the finite element method, and the unbending of the blade is realized by applying the simulation results so that the optimized design of flat preform for this process is executed. Moreover, the flat preform designed by the optimization is compared with that from geometry unbending and mechanical flattening, illustrating that results from the traditional unbending methods are obviously different from those of the finite element method. In the finite element method, the temperature field, the workpiece positioning and the plastic deformation during the practical process are considered, so that an accurately positioned flat preform with small and uniform allowance and good die contact state can be designed. Therefore, a notable progress is made as compared with the well-known geometry unbend and mechanical flattening. In addition, it is proved that the preform designed with the finite element method can be directly used in production without trials and errors, resulting in the save of material consumption and the productivity enhancement.