This article presents the results of experimental research on the effect of high-speed machining (HSM) in the milling process on the tool wear, surface layer properties, and fatigue life of objects made of Ti-6Al-4V titanium alloy. Titanium alloys are widely used in many industries due to their high strength-to-density ratio, corrosion resistance, and resistance to dynamic loads. The experiment was conducted on a vertical three-axis machining centre, Avia VMC800HS. The influence of increased cutting speeds on the average values and amplitudes of the total cutting force components and the surface roughness of the machined workpiece was determined. Variable cutting speeds v_c = 70; 130; 190; 250; 310 m/min were applied. The impact of HSM on machinability indicators, such as the microhardness of the surface layer, the distribution of residual stresses, and the fatigue life of the samples after milling, was analysed. The thickness of the hardened layer varied from 20 to 28 micrometres. The maximum compressive residual stress Ϭ_m = 190 MPa was achieved at the speed of v_c = 190 m/min. A significant influence of increased cutting speeds on tool wear was demonstrated. The longest tool life (t = 70 min) was obtained for low cutting speeds (conventional) v_c = 70 m/min.

This paper presents the results of an experimental study on the impact of slide burnishing on surface roughness parameters (Sa, Sz, Sp, Sv, Ssk, and Sku), topography, surface layer microhardness, residual stress, and mean positron lifetime (τ_mean). In the study, specimens of X6CrNiTi18 stainless steel were subjected to slide burnishing. The experimental variables were feed and slide burnishing force. The slide burnishing process led to changes in the surface structure and residual stress distribution and increased the surface layer microhardness. After slide burnishing, the analyzed roughness parameters decreased compared with their pre-treatment (grinding) values. The slide burnishing of X6CrNiTi18 steel specimens increased their degree of strengthening e from 8.77% to 42.74%, while the hardened layer thickness g_h increased after the treatment from about 10 µm to 100 µm. The maximum compressive residual stress was about 450 MPa, and the maximum depth of compressive residual stresses was g_σ = 1.1 mm. The positron mean lifetime τ_mean slightly yet systematically increased with the increase in burnishing force F, while an increase in feed led to changes of a different nature.

This study investigated the effect of the different surface treatment methods on the strength of Ti6Al4V titanium alloy sheet adhesive joints. The following surface treatment methods were used: alkaline degreasing, anodizing, vibratory shot peening, and anodizing with vibrational shot peening. The following tests/measurements were carried out during the experiment: surface roughness measurements; microhardness measurements (conducted by the Vickers hardness test method); and strength tests of single-lap adhesive joints fabricated with the use of two epoxy adhesives, rigid and flexible, both based on epoxy resin Epidian 5. It has been found that the application of anodizing followed by vibratory shot peening leads to increased strength of adhesive joints, irrespective of the type of applied epoxy adhesive.

We study the dynamics of a milling process of carbon fiber reinforced plastic based on experimental time series of cutting force with help of recurrence plots and recurrence quantifications methods. The two cases of composite machining are analyzed in detail. The first case is a milling of undamaged material, while the second is a milling of damaged material. The detailed recurrence analysis shows interesting results, and additionally some of all quantifications can be used to damage detection.

This paper presents the results of experimental research on the stability of a milling process for producing a thin-walled part made of AL7075 aluminium alloy. The part was machined on a CNC milling machine with a decreasing wall thickness. The acceleration and cutting forces in the process were measured and analyzed to determine stability limit using classical stability diagrams as well as recurrence plots and recurrence quantification analysis.