OBRABOTKAMETALLOV Vol. 26 No. 2 2024 technology Ra is the arithmetic mean deviation of the roughness profile, μm; d is the milling cutter diameter, mm; d1 is the diameter of the milling cutter shank, mm; l is the length of the working part of the milling cutter, mm; L is the full length of the milling cutter, mm; a is the clearance(rear) angle, degree; g is the rake angle, degree; ω is the angle of inclination of the chip groove, degree; z is the number of teeth, pcs; r is the radius of rounding (sharpness) of the cutting edge, μm; Ra (r) is the arithmetic mean deviation of the roughness profile on the cutting edge, μm; b is the wedge angle, degree; t is the milling depth, mm; B is the milling width, mm; V is the cutting speed, m/min; n is the rotation speed, rpm; fmin is the feed per minute, mm/min; Q is the volume of the material to be removed (cutting capacity), mm3/min. Experiment technique Specimen (shape, properties, structure) The workpiece (after its final preparation – the specimen) for testing was obtained using direct laser deposition technology (LMD – Laser Metal Deposition) from powder raw materials of the Fe-Cr-Ni-Ti system. Changes in the irradiation parameters (laser power, irradiation rate and the distance between layers) affect the size of the melt bath and the porosity of the structure of the resulting material, and, consequently, the mechanical properties of additively manufactured workpieces [31]. Therefore, the workpieces were obtained in the spent modes under the same conditions from the powder of the same delivery batch sequentially in the same modes (Table 1) and along the same deposition trajectory (Fig. 1). The specimens were obtained by successive unidirectional filling vectors: feeding along the specimen at a VLMD velocity, then feeding across the specimen by y = 1.67 mm, and so on until the first layer was obtained. Then by moving to the thickness of one layer (hwidth = 0.8 mm), moving to the starting point of synthesis of the first layer, filling along the long side of the sample, etc. All workpieces were obtained from a powder mixture, the passport and certified composition of which is given (Table 2). The resulting workpieces after growing had dimensions of 190×100×14 mm. The crust on workpieces was removed by electroerosion cutting. The latter made it possible to eliminate the appearance of distortion of internal stresses on the machined surfaces. Specimens for physical and mechanical tests were cut out of several workpieces. In order to avoid the spread of values caused by the location of the specimens relative to the workpiece, a check was carried Ta b l e 1 LMD modes for steel 0.12-Cr18-Ni10-Ti (AISI 321) products manufacturing Steel Plaser, W Dialaser, mm xwidth, mm hwidth, mm VLMD, mm/s Qpowder, mm3/min 0.12-Cr18-Ni10-Ti (AISI 321) 2,400 2.7 1.67 0.8 25 16
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