Preform effect on the plastic deformation behavior of workpieces in equal channel angular pressing

Preform design is an effective means of achieving the homogeneous deformation of workpiece materials and decreased load in metal forming. However, this approach has not been applied to equal channel angular pressing (ECAP). In this paper, the plastic deformation behavior of workpieces having three different preform shapes during ECAP was investigated using experimental and finite element analyses. The results indicated that a preform design slant at the back part of the workpiece head is beneficial to homogeneous deformation, reducing the maximum pressing load at the initial stage and eliminating folding defects at strain concentration points.