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EN
Effect of shells number (1–5) on tensile properties of PLA samples printed using the FDM/FFF technique was investigated. The crack surface was also analyzed. The best properties were obtained for 4-shell sample. However, due to the large coefficient of variation (>> 10%) in the case of elongation, 3-shell sample was selected for testing the machining impact. Such a large coefficient of variation can be explained by the presence of voids between the layers. The greater the number of layers, the greater the structure defects. Machining increases surface smoothness while reducing tensile strength and practi¬cally unchanged elongation at break.
PL
Zbadano wpływ liczby warstw (1–5) na właściwości mechaniczne przy rozciąganiu próbek PLA otrzymanych techniką FDM/FFF. Analizie poddano także powierzchnie pęknięć. Najlepsze właściwości uzyskano dla próbki 4-warstwowej. Jednak, ze względu na duży współczynnik zmienności (>> 10%) w przypadku wydłużenia, do badań wpływu obróbki skrawaniem wytypowano próbkę 3-warstwową. Tak duży współczynnik zmienności można wyjaśnić obecnością pustych przestrzeni pomiędzy warstwami. Im większa liczba warstw, tym większe defekty struktury. Obróbka skrawaniem zwiększa gładkość powierzchni przy jednoczesnym zmniejszeniu wytrzymałości na rozciąganie i praktycznie niezmienionym wydłużeniu przy zerwaniu.
PL
W artykule przedstawiono rezultaty badań ukazujących wpływ dodatku eksploatacyjnego do płynu roboczego na temperaturę styku powierzchni współpracujących w węźle tarciowym. Stwierdzono zróżnicowany wpływ zależny od stężenia tego dodatku.
EN
In this paper the results of studies showing the effect of the operating additive to the working fluid on the contact temperature of the cooperating surfaces in the friction pair were presented. Differentiated effects, depending on the concentration of the additive, were observed.
PL
W artykule przedstawiono specyficzne cechy procesu produkcyjnego elementów o dużych gabarytach. Wskazano cechy specyficzne obróbki dużych elementów. Wnioski sformułowano na podstawie własnych badań autorów: eksperymentalnych i analitycznych.
EN
In this paper the specific features of the production process of elements with large dimensions were presented. Specific features of machining large machines’ elements were indicated. The conclusions were formulated on the basis of the authors’ own research: experimental and analytical.
EN
Reducing energy consumption is a necessity towards achieving the goal of net-zero manufacturing. In this paper, the overall energy footprint of machining Ti-6Al-4V using various cooling/lubrication methods is investigated taking the embodied energy of cutting tools and cutting fluids into account. Previous studies concentrated on reducing the energy consumption associated with the machine tool and cutting fluids. However, the investigations in this study show the significance of the embodied energy of cutting tool. New cooling/lubrication methods such as WS2-oil suspension can reduce the energy footprint of machining through extending tool life. Cutting tools are commonly replaced early before reaching their end of useful life to prevent damage to the workpiece, effectively wasting a portion of the embodied energy in cutting tools. A deep learning method is trained and validated to identify when a tool change is required based on sensor signals from a wireless sensory toolholder. The results indicated that the network is capable of classifying over 90% of the tools correctly. This enables capitalising on the entirety of a tool’s useful life before replacing the tool and thus reducing the overall energy footprint of machining processes.
EN
In this paper a novel approach for monitoring tool-related faults in milling processes by utilizing process simulation-based machine learning algorithms, specifically Random Forest algorithms, for fault detection is presented. In order to train machine learning models in tool condition monitoring, laboratory tests have traditionally been required. This method eliminates the need for costly, time-consuming laboratory tests. The training process has been simplified by utilizing analytical simulation data and provides a more cost-effective solution by leveraging analytical simulation data. Based on the results of this study, the proposed approach has been demonstrated to be 94% accurate at predicting tool-related faults, demonstrating its potential to serve as an efficient and viable alternative to conventional methods. These findings have been supported by actual measurement data, with a notable accuracy rate of 93% in the predictions. Furthermore, the results indicate that process simulation-based machine learning algorithms will have a significant impact on the tools condition monitoring and the efficiency of manufacturing processes more generally. To further enhance the capabilities of the proposed fault monitoring system, process-related and machine-related faults will be investigated in future research. Several machine learning algorithms will be explored as well as additional data sources will be integrated in order to enhance the accuracy and reliability of fault detection.
EN
Sawing is often the first work step in the metal cutting production chain. Especially for larger workpieces, bandsawing is used for this purpose. Nevertheless, studies on sawing have led a niche existence in the research landscape for a long time. However, as a result of the optimization of manufacturing processes in terms of economic efficiency, bandsawing is increasingly becoming the focus of research, since there are still saving potentials here. The aim of this paper is to investigate the extent to which the bandsawing process can be influenced by active, low-frequency vibration superimposition in the feed direction. First, analogue tests were carried out and parameter combinations were determined which have a positive influence on the process. Subsequently, these parameter combinations were investigated on a real sawing machine with an excitation unit, analysing the extent to which the results from the analogue tests could be transferred to the real process.
7
EN
Many newer higher strength materials are being synthesized for variable automobile, aerospace and manufacturing applications in the present scenario. Since it is very difficult to cut such materials using conventional machining process, it is important to utilize unconventional machining process. In the present study, a detailed survey has been made to analyze the influence of various process parameters, effects of electrodes, optimization and electrolytes on performance measures in Electro chemical machining process. The effects of pulse related parameters on electrode materials, coating materials and its thickness on material removal, overcut and surface topography were investigated under different perspectives such materials, electrolyte and machining parameters. From the detailed literatures, it has been inferred that still lot of research works have been required to find the suitable electrolytes and their combination during the machining process. It has also been found that the performance measures of the machining process can be improved by adopting different and suitable optimization algorithms.
EN
The wettability of nitrogen and argon implanted WC-Co indexable knives used for wood-based material machining. An attempt was made to examine the effect of the depth profiles of the implanted ions on the wettability of ion implanted WC-Co tools used for wood-based material machining. The tests were carried for two types of the tool surfaces, i.e. initial and polished, two commonly used gases, i.e. nitrogen and argon, and for the values of the parameters, possible to control in the case of classic ion implanters. Four depth profiles were modelled for two different values of the acceleration voltage, two for each implanted element. The modelling parameters were selected so that the two modelled depth profiles for both implanted elements were similar. The wettability tests were carried using a computer-supported test stand. The obtained results did not confirm the hypothesis about the relationship between the wettability and the position and the shape of the depth profiles.
PL
Zwilżalność implantowanych azotem i argonem narzędzi WC-Co, wykorzystywanych w obróbce materiałów drewnopochodnych. Podjęto próbę sprawdzenia wpływu profili głębokości implantowanych jonów na zwilżalność implantowanych jonowo narzędzi WC-Co, stosowanych do obróbki materiałów drzewnych. Badania przeprowadzono dla dwóch rodzajów powierzchni narzędzi, tj. wyjściowej i polerowanej, dwóch powszechnie stosowanych gazów, tj. azotu i argonu oraz dla wartości parametrów możliwych do uzyskania w przypadku klasycznych implantatorów jonów. Zamodelowano cztery głębokościowe profile dla dwóch różnych wartości napięcia przyspieszającego, po dwa dla każdego implantowanego pierwiastka. Parametry modelowania dobrano tak, aby dwa modelowane profile głębokości dla obu implantowanych pierwiastków były podobne. Badania zwilżalności były prowadzone na wspomaganym komputerowo stanowisku testowym. Uzyskane wyniki nie potwierdzają hipotezy o zależności między zwilżalnością a położeniem i kształtem głębokościowych profili implantowanych pierwiastków.
EN
The main objective of the presented research is to analyze the dynamics of table motion of a CNC FV580A 3-axis milling machine during machining with fixed technological cutting parameters. The research includes the measurement of velocity, acceleration and deceleration, as well as distance and time parameters related to the movement of the machine's table during starting and braking during work tests. The results of the measurements were recorded using a Phantom v1610 high-speed video camera equipped with a Nikon ED AF NIKKOR 80:200 mm 1:2.8D lens, dedicated to the analysis of high-speed phenomena. The analysis presented in the publication includes a comparison of the results of the motion parameters obtained as a function of the feed motion speed vf. The results of the obtained tests and their analysis are discussed and presented in graphs and tables.
EN
Problems on the world market, related to delays in supply chains, have forced enterprises to adopt a more flexible approach in the production processes of the offered products. In order to meet customer needs, companies can often look for alternative supply chains, as well as take over the production of key components necessary to maintain business continuity. Therefore, companies have to make important decisions in the context of management. A simulation model may be a tool helpful in making decisions related to production planning, which, based on the actual data collected from the process, allows for the verification of decisions before entering them into the real system. The motivation to conduct the research was the search for answers: How entrepreneurs, while maintaining profitability, can ensure the continuity of production processes by searching for alternative production methods. The article considers a comparison of two production processes for the production of a shield type product: classic production - on a lathe and hybrid production using the SLM method and machining only technologically significant surfaces on a lathe. The main goal of the research is to compare two production processes: classic and hybrid in terms of efficiency, energy efficiency and production costs. The research takes into account the use of different laser powers and the possibility of incremental production of several products at the same time. In order to achieve the assumed goal, a simulation model was used to carry out the research, which was developed on the basis of preliminary experimental studies. A series of simulations were performed, taking into account the variability criteria, and then the efficiency, energy efficiency and profitability of using alternative production methods were analysed.
11
Content available remote Nowoczesność z tradycją – nowe trendy w rozwoju obróbki ubytkowej
PL
W niniejszym opracowaniu autorzy zaprezentują krótką charakterystykę wybranych technologii w zakresie obróbki ubytkowej. Stanowią one idealne rozwiązanie zarówno w produkcji wielkoseryjnej, w tym również w obróbce specjalizowanych części maszyn i materiałów trudnoobrabialnych, niejednokrotnie o skomplikowanych finalnych kształtach, jak i w pracach naukowo- badawczych wymagających precyzji technologicznej i dokładności wymiarowej elementów niezbędnych w prowadzonych eksperymentach.
EN
In this paper, the authors present a brief description of selected technologies in the field of subtractive manufacturing. They are an ideal solution both for large-scale production, including the machining of specialised machinery parts and difficult-to-machine materials, often of complex final shapes, as well as for scientific and research works requiring technological precision and dimensional accuracy of elements necessary in the conducted experiments.
EN
The article presents the research results on the influence of the PVD coating on the cutting tool on the surface roughness and energy consumption in the cast iron turning process. It was shown that using coated tools leads to obtaining a surface qualitatively corresponding to the ground surface and to reducing the power consumption of the machine tool. In addition, the process itself, carried out without a cooling and lubricating liquid, is more eco-friendly, as it excludes its use, disposal and negative environmental impact.
PL
Artykuł dotyczy charakterystyki procesu projektowania, programowania oraz budowy zrobotyzowanego stanowiska do procesu obróbki skrawaniem elementów odlewanych. W artykule omówiono sposoby projektowania, opracowany proces adaptacji narzędzia oraz wykonane symulacje. Scharakteryzowany został proces programowania z wykorzystaniem podejścia hybrydowego. Pokazano proces budowy oraz testów wykonanych na stanowisku laboratoryjnym oraz w warunkach przemysłowych.
EN
The article concerns the characteristics of the design, programming and construction of a robotic station for the machining of cast elements. The article discusses the design methods, the developed tool adaptation process and the simulations performed. The programming process was characterized by a hybrid approach. The construction process and tests performed on a laboratory stand and in industrial conditions are shown.
PL
W artykule przedstawiono niekonwencjonalne metody przecinania materiałów konstrukcyjnych realizowanych we współczesnych procesach wytwarzania. Do tej grupy zaliczono przecinanie strugą wodną i wodno-ścierną a także przecinanie elektroerozyjne. Wskazano cechy pozytywne tych metod oraz kryteria jakimi powinno kierować się przy wyborze najlepszego sposobu przecinania.
EN
In this paper unconventional methods for cutting construction materials that are realized in modern manufacturing processes were presented. This includes cutting with water and abrasive-water jets and erosion treatment. It shall indicate their positive features and the criteria according to which the method should be selected.
15
Content available remote Vibration analysis of a turning tool with passive damping
EN
Mechanical vibrations generated during machining can cause many problems in production processes. Vibrations can cause high dynamic loads leading to damage of the machine spindle, the cutting tool or the workpiece. Another unwanted effect of the existence of vibration during the machining process can be a deterioration in the quality of the machined surface. In this paper, a comparative analysis was carried out based on studies of the face turning process with conventional knives and those equipped with passive vibration damping systems. The results show the influence of the implemented vibration damper on the cutting process.
PL
Drgania mechaniczne pojawiające się podczas obróbki skrawaniem mogą być przyczyną występowania wielu problemów w procesach produkcyjnych. Drgania mogą powodować duże obciążenia dynamiczne prowadzące do uszkodzenia wrzeciona obrabiarki, narzędzia skrawającego lub przedmiotu obrabianego. Innym niepożądanym efektem występowania drgań w czasie procesu obróbki mechanicznej może być pogorszenie jakości obrabianej powierzchni. W niniejszej pracy przeprowadzono analizę porównawczą na podstawie badań procesu toczenia czołowego powierzchni nożami konwencjonalnymi i wyposażonymi w pasywne systemy tłumienia drgań. Wyniki badań przedstawiają wpływ zastosowanego tłumika drgań na przebieg procesu skrawania.
EN
The quality of the geometric structure of a surface is influenced by factors such as the geometry of the cutting tool, the cutting conditions and the displacements in the tool-workpiece system. This paper describes the results of a study to analyse the influence of selected machining factors accompanying the face milling process on the geometric structure of the surface. During the machining tests, relative displacements in the T-W system were recorded, as well as the components of forces and moments of the face milling process for specimens made of grey cast iron. The tests were carried out on an AVIA VMC 800 milling centre, and the accuracy of the machined surface was checked. A Talysurf CCI - Lite Non-contact 3D Profiler, which was equipped with TalyMap Platinum software, was used to measure the geometric structure of the surface.
PL
Na jakość struktury geometrycznej powierzchni wpływają takie czynniki, jak: geometria narzędzia skrawającego, warunki skrawania oraz przemieszczenia w układzie narzędzie-przedmiot obrabiany. W artykule opisano wyniki badań, których celem była analiza wpływu wybranych czynników obróbki towarzyszących procesowi frezowania czołowego na strukturę geometryczną powierzchni. W trakcie prób skrawania rejestrowano przemieszczenia względne w układzie N-P oraz składowe sił i momentów procesu frezowania walcowo-czołowego próbek wykonanych z żeliwa szarego. Próby przeprowadzono na centrum frezarskim AVIA VMC 800. Sprawdzono dokładność wykonania powierzchni poddanej obróbce frezarskiej. Strukturę geometryczną powierzchni zmierzono profilometrem Talysurf CCI - Lite Non-contact 3D Profiler, wyposażonym w oprogramowanie TalyMap Platinum.
EN
The prediction of machining processes is a challenging task and usually requires a large experimental basis. These experiments are time-consuming and require manufacturing and testing of different tool geometries at various process conditions to find optimum machining settings. In this paper, a machine learning model of the orthogonal cutting process of Ti6Al4V is proposed to predict the cutting and feed forces for a wide range of process conditions with regards to rake angle, clearance angle, cutting edge radius, feed and cutting speed. The model uses training data generated by virtual experiments, which are conducted using physical based simulations of the orthogonal cutting process with the smoothed particle hydrodynamics (SPH). The ML training set is composed of input parameters, and output process forces from 2500 instances of GPU accelerated SPH simulations. The resulting model provides fast process force predictions and can consider the cutter geometry in comparison to classical analytical approaches.
EN
The aim of this work is to present a new methodology for the automated analysis of the cross-sections of experimental chip shapes. It enables, based on image processing methods, the determination of average chip thicknesses, chip curling radii and for segmented chips the extraction of chip segmentation lengths, as well as minimum and maximum chip thicknesses. To automatically decide whether a chip at hand should be evaluated using the proposed methods for continuous or segmented chips, a convolutional neural network is proposed, which is trained using supervised learning with available images from embedded chip cross-sections. Data from manual measurements are used for comparison and validation purposes.
EN
The increasing needs of using aluminum epoxy composite as a replacement to solid metal rapid prototyping has opened to interests in optimizing its machining processes. This paper reported on the success of optimizing the surface roughness of aluminium epoxy composite using milling process along with a new finding on the best combination parameters. Taguchi method was used as the optimization method whereas spindle speed, feed rate, and depth of cut were set as input factors using an L9 Orthogonal Array. Analysis of Variance was used to identify the significant factors influencing the surface roughness. Experiment was conducted in dry condition using a vertical milling machine and the surface roughness after the machining was evaluated. Optimum combination of cutting parameters was identified after the finest surface roughness (response) based on the signal-to-noise ratio calculated. Cutting parameters selected after preliminary testing are cutting speeds of (2000, 3000 and 4000) rpm, feed rate (300, 400 and 500) mm/min, and cutting depth (0.15, 0.20, and 0.25) mm. The result showed that cutting speed had the largest percentage contribution to surface roughness with 69% and the second highest contribution was feed rate with 22% and depth of cut at 9%. The spindle speed was found as the most significant factor influencing the quality of surface roughness. The result is significant particularly in providing important guidelines for industries in selecting the right combination of parameters as well as to be cautious with the most significant factor affecting the milling process of metal epoxy composite.
EN
This work investigates the compaction behaviour of commercial pure aluminium chips (CP Al) produced during a machining operation and subsequently consolidated by Equal Channel Angular Pressing (ECAP). Empirical models were developed to describe the relative density and hardness of the compacted product of ECAP as functions of the initial machining input parameters including cutting edge angle (CA), depth of cut (DOC) and then the number of consolidation pass during ECAP. The models were developed utilizing response surface methodology (RSM) based on data from a central composite face centred factorial design of experiments approach. The models were then validated by using Analysis of Variance (ANOVA). The effect of input parameters on the relative density and hardness of the ECAP consolidated samples are presented and discussed including details as regards to the mechanical and microstructural properties. An optimum set of input parameters are identified and presented where the best relative density and hardness are demonstrated.
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