OBRABOTKAMETALLOV TECHNOLOGY Vol. 26 No. 1 2024 Ta b l e 3 Mechanical and physical properties of the processed alloy D16T Material grade Ultimate strength σu, (MPa) Ultimate elongation δ, (%) Heat conductivity factor λ, (W/m·K) Volumetric specifi c heat СV, (MJ/m3·K) Temperature diff usivity coeffi cient ω, (m2/s) Density ρ, (kg/m3) D16T 460 10 120 2.43 5.44ˑ10−5 2,800 Fig. 7. Hanita 4002 carbide 2-tooth milling cutter temperature during milling, a non-contact method was used, which allows continuous readings to be taken at a certain distance. The registration of measurements recorded using a Fluke Ti400 thermal imager with a temperature fi eld measurement error of 2 %. In the settings of the thermal imager, the radiation coeffi cient characteristic of aluminum alloys was selected, equal to 0.25. All mechanical processing tests carried out on a multi-axis boring machine 2431SF10 with a DRU with an upgraded spindle, which allows reaching a rotation speed of 18,000 rpm. The experiments were carried out with fi xed feed values per tooth and diff erent values of cutting speed. The experimental system “tool – workpiece – thermal imager” is shown in fi gure 8. Figure 9 shows an example of non-contact temperature measurement for the following cutting modes: a) n = 8,000 rpm; V = 251.2 m/min; Sz = 0.183 mm/tooth; b) n = 10,000 rpm; V = = 314 m/min; Sz = 0.183 mm/tooth. Based on the results of the experimental data, a graph made of the temperature dependence on the change in the factor (in this case, the cutting speed) at all fi ve levels of variation (fi gure 10). To increase the accuracy of cutting temperature calculations, we also took into account the fact that the properties of the material being processed change with changes in the deformation temperature. The test results can be summarized and presented in tabular form, where the average values of the experimental cutting temperature obtained from the results of three tests for each of the fi ve levels of variation in cutting speed are calculated. The ratio errors in comparing the temperature values are also calculated (Table 4). The average cutting temperature was compared with the average temperature of the contact surfaces of the cutting blade (eq. 19) and this result can be represented as a graph (fi gure 10): Based on the results of experimental tests and theoretical modeling, a temperature graph is made (fi gure 11). As a result of the work done, a mathematical model for calculating the temperature for high-speed milling of the studied group of aluminum alloys was developed. This model is based on reference data on high-temperature deformation of aluminum alloys, data on the mechanical and thermal and Fig. 8. Experimental system for temperature measurement
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