Impact vibration knurling of structural steel

The work is devoted to the study of impact vibration knurling of structural steels. Vibratory knurling differs from conventional knurling in that the deforming element is additionally given a reciprocating (oscillating) motion along the axis of the workpiece. The oscillating movement of the deforming element creates a sinusoidal trace of the tool, which is superimposed on the helical line formed as a result of the kinematic connection between the workpiece and the tool. The change in the size of the workpiece when a completely new microrelief is formed depends on the parameters of the initial roughness, the size of the deforming element and the machining modes. This paper presents the results of experimental study of the dependence of surface roughness, surface hardness and geometrical dimensions on the change of parameters of shock vibration knurling. The dependence of the height of profile irregularities on the nominal depth of indentation, feed, diameter of deforming ball for different steel materials is given. The dependence of surface hardness on the nominal depth of indentation, feed, diameter of the deforming ball and the dependence of the average pitch of irregularities on the feed for the investigated grades of structural steel was obtained.