Slip-line field theory

Summary

Slip-line field theory is a method for solving plane strain problems of rigid–perfectly plastic bodies, such as metal forming, indentation and cutting. In the plastic region the directions of maximum shear stress form two orthogonal families of curves, the slip lines. The stress equations are hyperbolic and the slip lines are their characteristics. So the problem reduces to building a net of curves along which simple relations hold. These relations are Hencky's theorems on slip lines, and the theory is a classical part of plasticity.