This paper presents the results of experimental study of the AZ31 magnesium alloy milling process. Dry milling was carried out under high-speed machining conditions. First, a stability lobe diagram was determined using CutPro software. Next, experimental studies were carried out to verify the stability lobe diagram. The tests were carried out for different feed per tooth and cutting speed values using two types of tools. During the experimental investigations, cutting forces in three directions were recorded. The obtained time series were subjected to general analysis and analysis using composite multiscale entropy. Modelling and prediction were performed using Statistica Neural Network software, in which two types of neural networks were applied: multi-layered perceptron and radial basis function. It was observed that milling with high cutting speed values allows for component values of cutting force to be lowered as a result of the transition into the high-speed machining conditions range. In most cases, the highest values for the analysed parameters were recorded for the component F _x , whereas the lowest were recorded for F _y . Additionally, the paper shows that a prediction (with the use of artificial neural networks) of the components of cutting force can be made, both for the amplitudes of components of cutting force F _amp and for root mean square F _rms .

Harmful self-excited vibrations called chatter occur during cutting processes (milling and turning) as a result of the trace regeneration. Moreover, dynamics of milling process is also influenced by intermittent cutting teeth during cutting. The paper presents an analysis of two-dimensional nonlinear model of milling. The analysed model takes into account susceptibility of the tool and the workpiece. The dynamics of the milling process is described by the discontinuous differential equation with a time delay, which can cause process instability for various system parameters. Therefore, stability lobes diagram was determined numerically. In order to reduce harmful vibrations the concept of the use of active piezo-elements is presented here. In addition, the work shows numerical results of chatter control in open and closed loop

The paper examines a nonlinear one-degree-of-freedom model of the cutting process. The classical regenerative mechanism of chatter is enriched by an additional friction phenomenon which generates frictional chatter. Additionally, the nonlinear cubic stiffness of the tool is taken into account. The aim of the paper is to investigate interactions between regeneration and the frictional effect. The proposed model is solved by the multi-time scale method. The cutting process stability (trivial solution) is determined in order to produce stability lobe diagrams and determine the influence of friction on the process. Finally, the maps of chatter amplitudes are presented and new frictional stability lobe diagrams are proposed to analyse the influence of friction.

The article presents the results of an analysis of the influence of the technological parameters related to tool holder types on the vibrations occurring during the milling of AZ91D magnesium alloy. Magnesium alloys are very low-density materials and, therefore, are increasingly being considered as replacement materials for the more commonly used aluminium alloys. The tool used in the study was a carbide end mill with TiAlN coating, clamped in three different types of tool holder: ER collet, heat shrink, and Tendo E hydraulic. The milling tests used straight toolpaths at varied cutting speeds and feed per tooth values. Based on the vibration displacement and acceleration signals recorded during the machining tests, the following were analysed: maximum value, amplitude, and root mean square (RMS) value of the vibrations. As part of the study, composite multiscale entropy (CMSE) analysis was also performed, describing the level of disorderliness of the obtained vibration signals. The increase in machining parameters caused an increase in the values characterising the displacement and acceleration of the vibrations. It was noted that multiscale entropy might be an important parameter describing the vibration signal (both displacement and acceleration).