The Role of Friction in Plane-Strain and Axisymmetric Extrusion Problems

摘要

Extrusion processes through three basic types of curved dies have been treated: cosine, elliptic and hyperbolic. Upper-bound theorem is used in obtaining mean extrusion pressures and also in choosing the most suitable deformation pattern for extrusion through square dies. Both Tresca and Mises yield criteria have been used and consideration has been given to friction at the die-material interface. Results are given in analytical form and plotted over a wide range of process variables. (Author)