OBRABOTKAMETALLOV Vol. 26 No. 2 2024 technology first symbols in order Fz, Fx, Fy. When milling, it is impossible to measure (isolate) with a dynamometer the tangential Pz and radial Py cutting forces acting on the tooth of the cutter and, accordingly, from the tooth of the cutter to the dynamometer, due to the turn (rotation) of the cutter (Fig. 10). Fig. 10. Scheme of decomposition of cutting forces in a plane perpendicular to the axis of rotation of the mill During milling, only the forces acting from the cutter on the dynamometer can be measured: the feed force Ph acting along the feed direction of the table, and the lateral force Pv acting perpendicular to the feed direction. In this case, the long side of the dynamometer must be installed strictly perpendicular regarding the direction of the table feed, as shown in Fig. 9 and 10, or strictly parallel to the table feed. The designation of these components depends on the direction of the table feed. When mounting the dynamometer with the long side strictly perpendicular to the longitudinal feed of the table (see Fig. 9 and 10), these components of the cutting force have the following designation (indicated by the second symbols in order): Fz = Px, Fx = Ph, Fy = Pv. With a small cutting depth t = 1 mm and a significantly large mill diameter d = 12 mm (t/d ratio < 0.1) and the direction of the minute table feed fmin across the long side of the dynamometer, these directions correspond to another system of forces acting on the specimen (workpiece) from the side of the milling cutter tooth (indicated by the third symbols in order) at the moment when the milling cutter tooth is embedding in the workpiece: Fz = Px = Px, Fx = Ph ≈ Pz, Fy = Pv ≈ Py. The same colors (Fz – purple, Fx – blue, Fy – red) these forces and graphs of its changes are indicated on the monitor. Turning to the system of forces acting on the specimen (workpiece) from the side of the milling cutter tooth, the following approximations will be used: Px = Fz, Py ≈ Fy, Pz ≈ Fx. Thus, you need to understand that in the interface of the Kistler DynoWare software, at the moment when the cutter tooth is embedding in the workpiece, Fz means that in fact it is Px; Fy means that in fact it is Py; Fx means that in fact it is Pz. The surface roughness of the machined specimens was measured using a profilometer model SJ-210 from Mitutoyo (Japan) (Fig. 11). Measurements were performed on five arbitrary sections on the initial workpiece before milling and after removing a layer with a thickness equal to the width of milling B
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