## 5 Discussion
With the calculation of this maximum stress it is possible to justify why, despite the fact that the machine tool allows through the power delivered by it \(P_{c}\), it is not advisable to use the maximum cutting thickness \(a_{cc}\), because this will give rise to a stress \(S_{a_{cc}}\) that in most of the cutting speed values used exceeds the ultimate allowable stress \(S_{u}\) by the test material. Moreover, from that maximum thickness \(a_{cc}\) under the test with all the test cutting speeds \(V_{c}\), the estimated maximum stress \(S_{a_{cc}}\) exceeds the yield strength \(S_{y}\) of the test material, which will lead to exceeding the elastic limit of the workpiece, generating, at least, plastic deformations and thereby compromising the machining process. Figure 18 illustrates the behavior of the stress obtained with respect to the optimal cutting depth \(S_{a_{cc}}\) and the initial cutting depth \(S_{a_{cc}}\) defined by the characteristics of the electrical power delivered by the machine tool. The analysis presented in this article is focused on manual machining; however, the presented model can, in theory, provide cutting depth \(a_{c}\) values for automatic machines operating at higher cutting speed \(V_{C}\), from which an analysis of the variation of high cutting speeds for automatic machines is presented, it was observed that, at higher cutting speeds involved in the machining process, the resulting effort of the process is lower, and therefore, the reliability in the process increases significantly, which results in a point to consider when discussing the replacement of equipment or the simulation of the process under other allowed parameters of cutting speed for other types of machinery. Figure 19 summarizes the theoretical values when varying the speed from 35 to 1500m/min and the effort obtained from the process \(S_{a_{cc}}\). \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \(V_{c}\) & \(a_{c}\) & \(S_{a_{cc}}\) & \(S_{a_{cc}}\) & \(R_{c}\) & \(N_{P}\) & \(t\) & \(P_{c}\) & \(E_{prom}\) \\
**[m/min]** & **[mm]** & **[MPa]** & **[MPa]** & **[mm]** & **[Adim]** & **[min]** & **[Wi]** & **[J]** \\ \hline
16 & 0.248387 & 185 & 608.29 & 0.3582 & 31 & 54.25 & 48.1 & 2610 \\
17 & 0.248387 & 177 & 579.96 & 0.317272 & 31 & 54.25 & 48.1 & 2610 \\
18 & 0.248387 & 169 & 553.64 & 0.282999 & 31 & 54.25 & 48.1 & 2610 \\
19 & 0.248387 & 161 & 529.23 & 0.253993 & 31 & 54.25 & 48.1 & 2610 \\
20 & 0.427778 & 249 & 506.60 & 0.229229 & 18 & 31.5 & 82.9 & 2610 \\
21 & 0.427778 & 239 & 485.62 & 0.207918 & 18 & 31.5 & 82.9 & 2610 \\
22 & 0.427778 & 229 & 466.15 & 0.189446 & 18 & 31.5 & 82.9 & 2610 \\
23 & 0.427778 & 220 & 448.05 & 0.17333 & 18 & 31.5 & 82.9 & 2610 \\
24 & 0.427778 & 212 & 431.21 & 0.159187 & 18 & 31.5 & 82.9 & 2610 \\
25 & 0.427778 & 204 & 415.51 & 0.146707 & 18 & 31.5 & 82.9 & 2610 \\
26 & 0.427778 & 197 & 400.85 & 0.135638 & 18 & 31.5 & 82.9 & 2610 \\
27 & 0.641667 & 247 & 387.13 & 0.125777 & 12 & 21 & 124.0 & 2610 \\
28 & 0.641667 & 239 & 374.28 & 0.116954 & 12 & 21 & 124.0 & 2610 \\
29 & 0.641667 & 231 & 362.22 & 0.109027 & 12 & 21 & 124.0 & 2610 \\
30 & 0.641667 & 224 & 350.88 & 0.10188 & 12 & 21 & 124.0 & 2610 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Simulation results for different values of \(V_{c}\). Other parameters, such as cutting depth, are not considered because starting at values of 70 m/min, the minimum required cutting depth is \(a_{c}=2.56\) mm, the power consumed by the electric motor remains at \(P_{e}=497\) W, the number of passes is \(N_{p}=3\), and the machining time is \(t=5.25\) min. It should be noted that these simulated high speeds do not consider imbalances, vibration imperfections, or other loading factors, which must be analyzed in greater detail for high-speed analysis. Future work involves strengthening the decision-making model by incorporating more factors from the machining process. For now, the work completed is considered satisfactory.