What Does Slip Line Field Theory Mean?
The slip line field theory refers to an academic concept that is used to evaluate the stresses and forces responsible for the generation of deformation patterns in metals. The presence of deformation on a metal's surface is a key factor in the propagation of certain types of corrosion such as crevice intergranular corrosion.
Corrosionpedia Explains Slip Line Field Theory
Slip line field theory is based on the evaluation of any shear stress present in a material and how this affects material deformation.
As deformation occurs, inter-molecular forces that oppose the applied shear force are present. If the applied force is low, the intergranular forces resist the applied force and the material can resume its original state once the load is removed, and vice versa. However, a larger applied force may cause a permanent deformation of the material, or even material failure.
Shear strain is the ratio of deformation to original dimensions. In the case of shear strain, it is the amount of deformation perpendicular to a given line rather than parallel to it. The greater the shear strain, the greater the degree of deformation and the probability of intergranular corrosion.