Influence of the parameters of deforming cutting on the features of the resulting slotted filter structures

OBRABOTKAMETALLOV Том 23 № 4 2021 TECHNOLOGY Fig. 15. Slots with a skirt opened incompletely The distribution of the results obtained showed that in the feed range of 0.25...0.4 mm/rev, the dependancy known for deforming cutting remains: with an increase in the depth of cut when a certain ratio t/S is reached, destabilization of the DC process is observed with the manifestation of undesirable effects (doublets, triplets, strippings), and the larger the feed rate S , the greater the maximum depth of cut t max , at which the stability of the process is maintained. However, the strippings noted at the feed rate of 0.4 mm/rev are regular, in pairs. This can be considered as a limiting case of the pairwise grouping of slot walls, which is observed at lower feeds. At feed rates of 0.1...0.2 mm/rev with an increase in the depth of cut (see diagram in Fig. 9 and Fig. 16), there is a transition from uniform slots (group “ 1 ”) to the grouping of slot walls without strippings (group “ 2 ”), and then, with the beginning of the “skirt” formation, the slots again acquire a uniform structure (group “ 5 ”). Such dependancy was discovered for the fi rst time and can be explained by the peculiarities of the formation of burrs under different angles of exit of the tooltip from the material, which is directly affected by the depth of cut. In particular, the presence of a burr on only one of two slot walls in doublets and on one of three slot walls in triplets (see Fig. 12 and Fig. 16) may be the result of neighboring slot walls being attracted to each other by a common burr and subsequent stripping of the burr off of all slot walls except one. In the feed interval 0.06 ... 0.08 mm/rev, there is no “twinning” region; with increasing depth, there is a direct transition from uniform slots (group “ 1 ”) to uniform slots with the formation of a “skirt” (group “ 5 ”), Fig. 16. Evolution of the structures obtained with the depth of cut increase