THEORETICAL ANALYSIS OF THE REGULATIONS OF FORMATION OF THE ROUGHNESS OF THE TREATED SURFACE DURING GRINDING AND ABRASIVE POLISHING

Mathematical models for determining the roughness parameters of the treated surface during grinding with diamond wheels with cutting grains located at the same height and represented, respectively, in the form of cones (pointed grains), truncated cones (related to the wear of diamond grains) and spheres have been developed. It was established by calculations that in the first case the ratio of surface roughness parameters =4. In the second case, as the wear of diamond grains increases, the surface roughness parameter decreases, and the ratio can significantly exceed the value of =4. This corresponds to experimental data, according to which the ratio during grinding can vary within 4 ... 11, and during abrasive polishing it can reach a value of 30 or more, which is associated with a significant number of grains that participate in the formation of surface roughness. Even larger values of and, accordingly, smaller values of the parameter were achieved in the third case. From a physical point of view, this is related to a decrease in the known ratio (thickness of the cut to the radius of the grain) as a result of the transition from the cutting process to the process of elastic-plastic deformation of the processed material, since . Therefore, it is possible to significantly reduce the height parameters of the surface roughness during grinding and abrasive polishing by increasing the number of grains (in the form of a sphere), which participate in the formation of surface roughness, and their equal height location on the working surface of the abrasive tool.