## 3 Results and Discussion
### Tool Wear  
[PERSON] et al. [34] demonstrated that cutting edge wear is related to chip vibration frequency. They confirmed that the frequency of chip generation decreases as flank wear increases. Based on Figure 6, it can therefore be inferred that higher chip vibration frequencies are associated with cutting edges made of S205-coated cemented carbides. In the case of these inserts, the flank wear \(VB\) did not exceed 0.08 mm for all tested feed rates. Significantly greater wear was recorded on inserts made of 6160 ceramics. Therefore, it can be assumed that machining with ceramic inserts is accompanied by lower chip vibration frequencies. The effect of cutting speed on flank wear for S205 inserts is inconclusive. At both a cutting speed of \(v_{c}\) = 80 m/min and \(v_{c}\) = 200 m/min, the \(VB\) values are similar. However, for 6160 inserts, a clear influence of both cutting speed and feed rate on flank wear can be observed. An increase in feed rate leads to a reduction in flank wear, whereas an increase in cutting speed results in higher flank wear. The differences in \(VB\) wear values between the S205 and 6160 inserts are significant. While at a feed rate of \(f\) = 0.07 mm/rev, the wear of ceramic inserts is approximately twice that of cemented carbide inserts, at a feed rate of \(f\) = 0.025 mm/rev, the wear of ceramic inserts is more than three times greater than that of cemented carbide inserts. Figures 7-10 present wear symptoms of the S205 and 6160 inserts recorded on the rake and flank surfaces. A common feature observed in all tested tools is adhesive wear, including built-up edge (BUE) formation on both the rake and flank surfaces. The extent of wear varies depending on cutting parameters such as feed rate and cutting speed. However, Figure 7 demonstrates that the amount of material loss on the cutting edge also depends on cutting parameters such as feed rate and cutting speed. Figure 8 confirms that both feed rate and cutting speed influence the adhesion phenomenon. When machining at a feed rate of \(f\) = 0.025 mm/rev and a cutting speed of \(v_{c}\) = 80 m/min, the machined material spreads across the rake surface. Increasing the cutting speed to \(v_{c}\) = 200 m/min while maintaining the same feed rate results in the formation of a stable built-up edge on the cutting edge, which in this case protects the tool from abrasive wear on the flank surface. For a higher feed rate of \(f\) = 0.07 mm/rev, a persistent BUE along the cutting edge was observed after machining at \(v_{c}\) = 80 m/min. However, increasing the cutting speed to \(v_{c}\) = 200 m/min does not promote BUE formation on the rake surface or the cutting edge. The wear characteristics of the rake surface on the 6160 inserts differ from those observed on the S205 inserts. On the rake surface of the S205 inserts, a built-up edge formed, reflecting the cross-section of the chip. In the case of the 6160 inserts, the rake surface also exhibited a chip cross-section imprint, but only with scattered chip fragments within it (Figure 9a-d). This phenomenon is independent of feed rate and cutting speed. However, it was observed that increasing the cutting speed from 200 m/min (Figure 9c) to 250 m/min (Figure 8d) led to an increase in the number of microchips. Nevertheless, they do not form a compact BUE like the one observed on the S205 inserts. [PERSON] et al. [36], who studied the wear of ceramic cutting tools when machining Inconel 718, demonstrated that the primary wear mechanism of these tools is notch wear. The conducted research confirmed that using a cutting speed of \(v_{c}\) = 250 m/min with a feed rate of \(f\) = 0.025 mm/rev leads to an increase in notch wear (Figure 10b). This wear is twice as severe as that observed at a cutting speed of \(v_{c}\) = 200 m/min (Figure 10a). This phenomenon was not observed at a feed rate of \(f\) = 0.07 mm/rev. In this case, increasing the cutting speed did not lead to a rise in notch wear. Therefore, the extent of notch wear depends on both the feed rate and the cutting speed.