Investigation of the Required Discreteness of Interpolation Movement Parameters in Cyber-physical Systems

Improving the accuracy, reliability, and performance of cyber-physical systems such as high-speed machining, laser cutting, welding and cladding etc. is one of the most pressing challenges in modern industry. CNC system carries out data processing and significantly affect on accuracy of operation such equipment. The paper considers the problem of controlled axes motion differential characteristics data processing in the internal representation of the discrete space of the CNC system. Equations for determining the required discreteness of the differential characteristics position and resolution, such as the speed, acceleration, and jerk are proposed. For the most widely used CNC equipment specific discreteness and resolution values have been determined.

Fundamental Investigation into Tool Wear and Surface Quality in High-Speed Machining of Ti6Al4V Alloy

This paper reports a fundamental investigation consisting of systematic trials into the response of Ti6Al4V alloy to high-speed machining using carbide inserts. It is a useful extension to work previously published, and aims at assessing the impact of the process parameters, depth of cut, cutting speed and feed rate in addition to cutting length, and their interrelations, on observed crater and flank wear and roughness of the machined surface. The results showed that abrasion was the most important flank wear mechanism at high speed. It also showed that increased cutting length accelerated crater wear more than exhibited flank wear and had considerable effect on surface roughness. In particular, crater wear increased by over 150% (on average), and flank wear increased by 40% (on average) when increasing cutting length from 40 to 120 mm. However, cutting the same length increased surface roughness by 50%, which helps explain how progression of tool wear leads to deteriorated surface quality. ANOVA was used to perform statistical analyses of the measured data and revealed that cutting length and depth of cut had the greatest effect on both crater and flank wear of the cutting tool. These results confirm that high-speed machining of Ti6Al4V alloy is a reliable process, with cutting speed identified as having a relatively small influence on the tool wear and resultant roughness of the machined surface relative to other parameters.

Analysis and prediction of the impact of technological parameters on cutting force components in rough milling of AZ31 magnesium alloy

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 Fx, whereas the lowest were recorded for Fy. 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 Famp and for root mean square Frms.

Sustainability-Based Analysis of Conventional to High-Speed Machining of Al 6061-T6 Alloy

High-speed machining is considered to be a promising machining technique due to its advantages, such as high productivity and better product quality. With a paradigm shift towards sustainable machining practices, the energy consumption analysis of high-speed machining is also gaining ever-increasing importance. The current article addresses this issue and presents a detailed analysis of specific cutting energy (SCE) consumption and product surface finish (Ra) during conventional to high-speed machining of Al 6061-T6. A Taguchi-based L16 orthogonal array experimental design was developed for the conventional to high-speed machining range of an Al 6061-T6 alloy. The analysis of the results revealed that SCE consumption and Ra improve when the cutting speed is increased from conventional to high-speed machining. In particular, SCE was observed to reduce linearly in conventional and transitional speed machining, whereas it followed a parabolic trend in high-speed machining. This parabolic trend indicates the existence of an optimal cutting speed that may lead to minimum SCE consumption. Chip morphology was performed to further investigate the parabolic trend of SCE in high-speed machining. Chip morphology revealed that the serration of chips initiates when the cutting speed is increased beyond 1750 m/min at a feed rate of 0.4 mm/rev.

Study On The Cutting Performance of High-Speed Machining Zr-Based Bulk Metallic Glass

The cutting performance of high-speed machining (100-350 m/min) Zr57Cu20Al10Ni8Ti5 (at.%) bulk metallic glass (Zr57 BMG) was studied, as compared with industrial pure zirconium (Zr702). The effect of cutting speed on cutting force, surface roughness, surface morphology and chip morphology was analyzed. Although the strength of Zr57 BMG is much higher than that of Zr702, the difference in main cutting force is small, which can be attributed to the thermal softening of Zr57 BMG material during machining. The machined surface characteristics and the formation of chips were investigated. Different from low-speed machining, the groove marks and adhensions on machined surface evolve into wave patterns and molten droplets with the cutting speed increasing from 100 m/min to 350 m/min. The appearance of wave patterns tends to destroy the machined surfaces, and the worst quality was obtained at the speed of 250 m/min. The free surface morphology of the chips, with cutting speed smaller than 150 m/min, show obvious serration and molten droplets between shear bands. With the increase of cutting speed, oxidation on the chip surfaces occurred, and the chip surface was gradually covered by powder particles due to the melting of Zr57 BMG workpiece materials. The machined surfaces of Zr57 BMG maintain amorphous structures after high-speed machining, which shows excellent application potential for the processing of Zr57 BMG.