OBRABOTKAMETALLOV technology Vol. 26 No. 2 2024 Heat treatment methods (annealing, normalization, etc.) allow to provide phase transformations in the metal structure, and also significantly affect the physical and mechanical characteristics of the workpiece material, and, as a result, the resistance to cutting [5–9]. In order to give the final shape, maintain geometric accuracy and surface roughness, the additive workpiece is subjected to subtractive processing, i.e. machining with the removal of material. The latter can include the processes of blade and abrasive cutting. At the same time, it is important to understand that the removal of “excess” material (overlap or allowance) is accompanied by a range of specific phenomena – chip formation, the occurrence and dynamic change of cutting forces, temperature changes in the cutting zone, the gradual formation of wear on the working surfaces of the cutting tool, etc. [10–21]. Special attention is paid to the peculiarities of the interaction of the “tool material-machined material” pair. Observation and study of these phenomena contribute to the development of scientifically based recommendations on the choice and assigning of edge cutting machining modes, especially when it comes to machining new materials or workpiece obtained by additive methods – it becomes possible to indirectly estimate the economic costs of producing a fully functional product [4]. Significant progress has been made in the synthesis of stainless steels by various additive methods, which makes it possible to use the resulting workpiece of stable quality for further heat treatment, as well as to give the required structural design, roughness, shape and size accuracy by removing the allowance [22– 25]. In [26], a team of researchers studied the impact of additive manufacturing on the development of the space industry. The authors concluded that the repeatability and consistency of the mechanical properties of finished parts of additive manufacturing have not yet been fully studied, and special attention should be paid to the development of standards, certificates and inspection protocols. Scientific papers [15, 27–29] are devoted to the anisotropy of the properties of additive metallic materials. In the review work [29], the main factors that cause microstructural features and heterogeneity of mechanical properties are highlighted: grain morphology; crystallographic texture; defects in the absence of merger; phase transformations; heterogeneous recrystallization; banding of layers and microstructural coarsening. As a result, the anisotropy of the properties affects the resistance of the material to cutting. It is necessary to know the distribution of contact stresses on the rake surface and on the wear chamfer of the flank and back surface to calculate the milling teeth for strength, in addition to the cutting forces Pz, Py and Px acting on the milling tooth. The authors of [30] have developed a technique for constructing of a contact stresses diagram on the rake surface of the cutting wedge when turning steel, but it is also applicable in milling. The length of the chip contact with the rake surface of the milling cutter tooth at the largest cut thickness, i.e. for counter milling, this occurs at the moment preceding the tooth exhaust from contact with the workpiece should be known to do this. This contact length c can not only be measured, but also determined by graphs с = f (ai,g) [30], knowing the uncut chip thickness a (mm) at the end of the tooth contact with the workpiece: amax ≈ sz×2×(t/d) 1/2, where s z is the feed to the tooth, mm/tooth; t is the milling depth, mm; d is the diameter of the cutter, mm; γ is the rake angle of the cutting wedge. Designations (Nometclature) Plaser is the laser radiation power, W; Dialaser is the laser spot diameter, mm; xwidth is the width offset of the rollers, mm; hwidth is the height offset of the rollers, mm; VLMD is the LMD speed, mm/s; Qpowder is the powder consumption, g/min; s0.2 is the yield strength, MPa; sUTS is the ultimate tensile strength, MPa; d5 is the relative elongation, %; KCU is the impact strength, J/cm2;
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