The residual stress remaining in deformed matrix is evaluated on the basis of the active slip systems and the dislocations necessary for flow. The orientations of the recrystallized grains that are expected to grow preferentially in the internally stressed matrix are predicted by means of a new recrystallization model. The model involves two principles: i) a strain energy release maximization theory and ii) growth by {110} plane matching. The predictions obtained in this way are compared with experimental results and discussed in terms of the possible effect of the internal stresses produced by cold rolling on the recrystallization texture.

In metal forming, there are problems with recurrent geometric characteristics without explicitly prescribed boundary conditions. In such problems, so-called recurrent boundary conditions must be introduced. In this paper, as a practical application of the proposed method, the precision cold forging of a helical gear (which is industrially useful and geometrically complicated) has been simulated by a three-dimensional rigid-plastic finite element method and compared with the experiment. The application of recurrent boundary conditions to helical gear forging analysis is proved to be effective and valid. The three-dimensional deformed pattern by the finite element analysis is shown, and the forging load is compared with the experimental load. The profiles of the free surface of the workpiece show good agreement between the computation and the experiment.