| Abstrakt: |
Friction at the die-metal interface results in nonuniform deformation in metal compression. With sticking friction, the plastic flow mechanism becomes extremely complex, and the force and energy requirements are higher compared to frictional compression. Earlier research, which had some limitations, enables evaluation of the forming load in metal compression involving sticking friction. In the present article, critical analysis has been made regarding frictional behavior at the real contact areas to propose a more realistic estimation of frictional constraints. For this purpose, available inferences in specific areas of metal forming, concerning fundamental concepts of friction and the influence of interface shear stress, bulk deformation, etc., on frictional behavior, have been used and modified as required. Also, a rational deformation kinematics has been proposed, assuming velocity discontinuity at every point within the flow field. The proposed estimation of friction and plastic flow kinematics yields results in line with the published experimental findings and the corresponding slip-line field solutions. |
Full text from SpringerLink