The process of drawing thin carbon steel wires through conical dies is used as an experimental method for determining the effect of frictional conditions and die angle on the generation of fine grain layers in the vicinity of the friction surface. In this study, a quantitative criterion for determining the thickness of fine grain layers is proposed. The criterion is based on the coefficient of anisotropy that characterizes the shape of grains. It is shown that fine grain layers are generated under all frictional conditions investigated, but the thickness of the layer depends on these conditions and die angle.
