This study examines the impact of PVD coatings on cutting tool wear during the milling of 316L stainless steel under air cooling conditions. In the experiment, a carbide milling cutter coated with a nanocomposite nACo3 (AlTiSiN) coating was used. The coating was deposited using a next-generation device, the PLATIT π411PLUS, which features one central and three lateral rotating cathodes. The nanocomposite nACo3 coating obtained with this method exhibits exceptionally high structural density and excellent mechanical properties. The new generation of the nACo3 coating demonstrates improved surface properties and a lower friction coefficient compared to previous generations. The findings indicate that PVD nACo3 coatings significantly enhance wear resistance, extending tool life while maintaining acceptable surface quality. The optimal cutting time was determined to be approximately 90 min, after which a sharp increase in surface roughness and tool wear was observed. After 120 min of machining, substantial deterioration of surface quality parameters was recorded, suggesting increasing cutting forces and cutting edge degradation. SEM and EDS analyses revealed the presence of adhered material on the tool and sulfide inclusions in the microstructure of 316L stainless steel, which influenced the machining process. The nACo3 coating demonstrated high thermal and wear resistance, making it an effective solution for machining difficult-to-cut materials. This study suggests that selecting appropriate cutting parameters, tool geometry, protective coatings, and cooling strategies can significantly affect tool longevity and machining quality. The novelty of this research lies in the application of innovative nanocomposite PVD coatings during the milling of 316L stainless steel under air cooling conditions. These studies indicate potential future research directions, such as the use of minimum quantity lubrication (MQL) or cryogenic cooling as methods to reduce tool wear and improve post-machining surface quality.

The article presents the results of experimental studies of the milling process of Vanadis 4 Extra - tool steel 1.2210 with a four-flute AlCrN-coated end mill. On the basis of the measured values of the total cutting force F and the roughness parameters Ra and Rz of machined surfaces, the...

The article presents the results of experimental research on the grinding of corundum ceramics in the pre-sintered state, with spherical diamond heads. The aim of the experiment was to determine the effect of grain size and feed rate on selected aspects of the grinding process of corundum ceramics with the use of spherical diamond heads. In the experiment, grinding wheels with a ball diameter of 3 mm and different grain sizes were used; the grain numbers were D64, D91, D126 and D181. The tests were carried out on the Ultrasonic 20 Linear machining center at a constant rotational rate of the grinding wheel n = 38,000 rpm and a grinding depth of 30 mu m. The feed rate was set on 3 values: 200, 400 and 600 mm / min. During the research, the process temperature was recorded with a thermal imaging camera. The topography of grinding wheels before and after the grinding process and the topography of the ground surface were also measured. The parameters Sa and (S) over capz ((S) over capz = Spk + Sk + Svk) were used to characterize the grinding heads. The conducted analyses showed the dependence of the parameters Sa and (S) over capz of new grinding heads on the grain size described by the quadratic function (R-2 >= 0.94). Statistically significant changes in the parameters Sa and (S) over capz on the cutting surface of the grinding wheel, which occurred as a result of its wear, were observed. There was no significant relationship between the feed rate and the wear of grinding heads, probably due to the relatively small volume of the material removed. A positive correlation between the Sa and (S) over capz parameters of the ground object and the grain size was observed. The research also showed an increase in the process temperature with an increase in the feed rate and an increase in the grain size.

Powder metallurgy tool steels, such as Vanadis 4 Extra (1.2210), are increasingly used in cold-work applications due to their superior hardness, wear resistance, and microstructural uniformity. Despite their growing popularity, there is limited data regarding their machinability, especially in milling processes. In this study, experimental milling tests were performed on Vanadis 4 Extra steel using AlCrN-coated carbide tools. A full factorial experimental design (3⁴) was applied to investigate the effects of cutting speed, depth of cut, width of cut, and feed per tooth on cutting forces (Fx, Fy, Fz, Fc), surface roughness parameters (Ra, Rz), and tool wear. Cutting forces were measured using a Kistler dynamometer, and surface roughness was evaluated using a contact profilometer. Regression models were developed and statistically validated. The results indicate that depth of cut had the most significant influence on cutting force, while cutting speed had the greatest impact on surface roughness. Moderate correlation between cutting forces and roughness was observed, particularly under low-load conditions. SEM analysis revealed abrasive wear and chipping of the coating layer. The findings provide insights into the machinability of Vanadis 4 Extra and offer guidelines for optimizing milling parameters to enhance tool life and surface integrity.

Material Extrusion (MEX) additive manufacturing (AM) of ABS polymer components often requires post-process machining to achieve the necessary dimensional precision and surface quality. However, the influence of printing parameters and tool–material interaction in hybrid manufacturing remains insufficiently explored. This study investigates the impact of initial hole size (D_start), build orientation, and cutting parameters (cutting speed and feed rate) on the dimensional accuracy and surface roughness of machined holes in ABS-M30 specimens. Samples were fabricated in vertical and horizontal orientations and subjected to drilling in solid material and enlargement of printed pilot holes using a twist drill on a 5-axis machining center. Dimensional deviation and surface roughness (Ra, Rz) were evaluated using coordinate metrology and profilometry. The results showed that the smallest machining allowance (0.062 mm per side) was insufficient to completely remove the printing-induced surface texture, resulting in significantly higher and more variable Ra and Rz values. This distinct low-machining-allowance regime was confirmed by statistical analysis and representative optical observations. Conversely, a machining allowance of 0.565 mm per side (corresponding to D_start = 9 mm) resulted in substantially lower surface roughness (Ra ≈ 1.6 µm). Vertical build orientation generally provided better surface quality than the horizontal orientation, which was consistent with fewer visible surface features in the selected optical fields of view. All machining conditions resulted in negative dimensional deviations, indicating elastic recovery of the ABS material after machining. An exploratory multi-response ranking showed that the lowest composite quality scores for overall final hole quality were associated with D_start = 10 mm (machining allowance of 0.062 mm per side). When the analysis was limited to the machining-dominated regime, the lowest score was obtained for the vertical build orientation, D_start = 9 mm, a cutting speed of 40 m/min, and a feed rate of 0.2 mm/rev. These findings provide preliminary guidelines for selecting hybrid manufacturing conditions for MEX-manufactured ABS-M30 components.