Determination of cutting force when drilling foiled glass-cloth-base laminate

The paper presents the results of an experimental study of the cutting force while drilling holes of various diameters in laminate composite, i.e. foiled glass-cloth-base laminate. Due to its inhomogeneous structure, the material has processing limitations associated with bundles caused by uneven distribution of mechanical load. If the value of mechanical load is known, it is possible to predict the most optimal cutting conditions. During the experiments, we obtained the dependences of the change in the axial component of cutting force on the feed at different rotational speeds, grades of processed material and drill diameters. Three most widely used brands, that is Isola DE 104, GEM (ILM), and SF2-35 GOST10316-78, were selected as the material to be processed. We obtained a general rule for choosing the optimal cutting conditions for drilling laminated composite material. To assess the effect of tool blunting on axial thrust parameters, we conducted an experiment which consisted in applying dull drills with a diameter of 1 mm to all three types of material for all previously selected cutting modes. The analysis of experimental data showed that the dependences of the axial force on the feed when using tools of different diameters and different types of materials (epoxy bond between the layers, fiberglass cloth, fiber filament distribution, and different glass filling) at the same spindle speed are similar. The obtained dependences and regularities will make it possible to develop a force model for drilling composite materials, which may significantly simplify the operation design.