OBRABOTKAMETALLOV TECHNOLOGY Vol. 26 No. 1 2024 Δ , W v A T c ¢ = (8) where v c is the specifi c thermal capacity of the processed material. By virtue of formula (8), the part of equation (5), which is responsible for the temperature factor, is a function of the specifi c work of deformation. And the following equality is fair for it: ( ) 1 , W hA A W F A e - = (9) where 1 b V melt S A C T = is a dimensionless group. Now that all the parameters responsible for changing the yield stress during milling of aluminum alloys have been determined, it is possible to write the defi ning equation in diff erential form to determine the specifi c work of deformation: εε ε 1 . W m hA A W p p dA AK e d - = (10) The dependence of specifi c work on deformation during milling aluminum alloys allows obtaining an analytical expression for constructing the fl ow curve of these alloys: εε ε 1 . W m hA A W p p A AK e d - = (11) But since aluminum alloys (in particular D16T, AMg6M, 2024–T3) are practically not strengthened during milling, due to the action of such a softening factor as temperature [19], then the construction of an analytical fl ow curve does not make sense. However, it makes sense to determine the maximum values of the yield stress, that is achieved during milling [16, 17, 20, 21]. The front surface during high-speed milling is characterized by homological temperatures above 0.5, and therefore, graphically (fi gure 1, according to Rosenberg-Eremin) the coeffi cient Kq equal to 1.8 was determined. And for the back surface (near the cutting edge) homological temperatures from 0.3 to 0.35 are characteristic; therefore, the dynamic coeffi cient Kε equal to 1.25 was also determined graphically (fi gure 1, according to Rosenberg-Eremin). After compiling a defi ning equation for modeling changes in the properties of the material being processed under high-speed milling conditions, one can proceed to calculating temperatures. However, in this work, the term “temperature” should be applied to the surface of the cutting blade (tooth) on which this temperature occurs. In this regard, it is necessary to distinguish between the temperature that occurs on diff erent parts of the cutting blade, in particular on the front and back surfaces, as well as the temperature that results from these temperatures – the cutting temperature [26]. The cutting temperature is the result of the average temperatures occurring on the front and back surfaces of the cutting blade, related to the value of the coordinates on which these temperatures are distributed. It should be noted that during milling, measuring the temperature on the front and back surfaces of the cutting blade is very diffi cult, since the cutting area is closed in front with chips, and behind with the material (workpiece) being processed. Therefore, all temperature measurements will be compared with the cutting temperature, that is, with the temperature measured by the thermal imager, in order to observe the temperature distribution on the surface under study. To calculate the cutting temperature, a suffi ciently large number of factors should be taken into account. It can be divided into factors that relate to the material being processed, factors that relate to the tool, and factors that are characteristic of the cutting process itself (turning, milling, drilling, etc.). A necessary and obligatory condition for calculating the cutting temperature is the introduction of the mechanical and physical properties of the processed material into the model. These properties and characteristics for the group of aluminum alloys presented in Table 2 [18, 19]:
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