MODEL OF THE CUTTING MECHANISM IN GRINDING

In order to achieve optimum working results during grinding, information regarding both the kinematic relations and the structure of the multiple cutting-edge tool is necessary. In addition, the physical and metallurgical properties of the workpiece material and the specific influence of the interfacial frictional effects must be taken into account. This paper presents a contribution to the understanding of the cutting mechanisms in grinding. An analysis of the grinding mechanism is made on the basis of the cutting-edge geometry and the kinetics involved. One physical model has been developed to explain all the phenomena from friction to ploughing and cutting under plane strain conditions. Starting from the velocity relation at an averaged penetrating cutting edge and characterizing frictional conditions at the interface between the cutting edge and the workpiece material, it is possible to calculate a slip-line field which satisfies all the existing boundary conditions. The flow pattern of the material can be drawn taking the corresponding hodograph into account. This results in a distortion of the square grid characterizing the material on passing through the region of plastic deformation. Agreement with cross sections of actual chip formation zones during grinding is observed. The significance of this analysis lies in the fact that it establishes a relation between chip formation and the resultant surface integrity. © 1979.