OBRABOTKAMETALLOV MATERIAL SCIENCE Том 23 № 3 2021 EQUIPMEN . INSTRUM TS Vol. 6 No. 2 2024 a b Fig. 6. Comparison of real (1, 3) and modeled (2, 4) geometrical topologies of the workpiece surface for: a – Sp (0) = 0.15 mm/rev; b – S p (0) = 0.25 mm/rev along the workpiece, but also the irregularities caused by the random component of cutter oscillations. The distance L = 15 mm between the peaks along the surface in the direction L corresponds to the feed rate when turning a workpiece with a diameter D = 114 mm. The given “skeletal” topologies 2 and 4 (fig. 6) are obtained by simulation studying without taking into account the random component in tool vibrations, which is a consequence of continuously changing tool geometry, plastic deformation of the metal and other numerous factors randomly appearing in the cutting process. However, the reconstructed geometrical surfaces are qualitatively similar to each other, and estimates of the roughness of the real surface Rai obtained by machining with constant cutting modes vary relative to the surface roughness predicted by simulation modeling Ra (Model) within the limits of not more than 0.066 μm (Table 3) for different feed modes. Ta b l e 3 Roughness for model and real data Sp (0) , mm/rev V3 (0), m/min tp (0), mm Ra(Model), μm Surface roughness measurement result for different experiments, µm Ra1 Ra2 Ra3 Ra4 Ra5 Ra6 Ra7 Ra8 Ra9 Ra10 0.15 190 0.5 0.94 0.934 0.937 0.960 0.967 0.964 0.964 0.966 0.985 0.985 1.001 0.25 190 0.5 1.25 1.184 1.200 1.237 1.243 1.214 1.217 1.279 1.240 1.305 1.304 The final experimental verification of the selected combinations of cutting modes was carried out on a modernized 16K20 universal lathe with a Mitsubishi stepless speed control system. Surface roughness was measured using a Mitutoyo Surftest SJ-210 profilometer with a measurement resolution of 0.0064 µm (fig. 7). On the basis of the obtained data of experimental and simulation realization of the workpiece surface, it can be concluded that the proposed methodology of simulation studying allows predicting the quality of the formed surface depending on the selected technological modes and vibration profile of the machine
RkJQdWJsaXNoZXIy MTk0ODM1