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EN
The present research employs the statistical tool of response surface methodology (RSM) to evaluate the machining characteristics of carbon nanotubes (CNTs) coated high-speed steel (HSS) tools. The methodology used for depositing carbon nanotubes was Plasma-Enhanced Chemical Vapor Deposition (PECVD). Cutting speed, thickness of cut, and feed rate were chosen as machining factors, and cutting forces, cutting tooltip temperature, tool wear, and surface roughness were included as machining responses. Three-level of cutting conditions were followed. The face-centered, Central Composite Design (CCD) was followed to conduct twenty number of experiments. The speed of cutting and rate of feed have been identified as the most influential variables over the responses considered, followed by the thickness of cut. The model reveals the optimized level of cutting parameters to achieve the required objectives. The confirmation experiments were also carried out to validate the acceptable degree of variations between the experimental results and the predicted one.
EN
Titanium super alloys are often used in the chemical and aerospace industries, especially because of financial savings, resulting primarily from cheaper operation of equipment. Machinability of titanium alloys is more difficult than that of other metals. In addition, the low thermal conductivity causes the alloy to stick to the cutting edge of the cutting tool, thereby causing it to become dull faster. The article deals with the experimental evaluation of cutting forces and the design of suitable cutting parameters for the machining of the UNS R56260 titanium alloy with high-feed milling technology. Testing was carried out in climb and conventional milling under different cutting conditions. The cutting components of forces Fx, Fy, Fz were measured and evaluated. The results of the measurements were processed into a graphical form and suitable cutting conditions were designed in terms of the acting cutting forces.
EN
Owing to their excellent strength-to-weight ratio aluminium composite materials are very readily used in the construction of means of transport. The parts made of such materials must be characterized by high reliability and workmanship. Hence, machining is the predominant method of manufacturing parts from composites. The problem with the turning, milling and drilling of ceramic-reinforced composites is the abrasive action of the reinforcement, resulting in heavy wear of the blades and so in lower surface quality and dimensional-shape accuracy and higher manufacturing costs. A solution to this problem can involve the blades made of superhard materials or properly matched conditions of machining with sintered carbide blades. This paper presents the results of the turning tests carried out on an aluminium composite material reinforced with long ceramic fibres. An uncoated sintered carbide blade is compared with a diamond coated blade and a polycrystalline diamond blade. Post-turning surface roughness and machining forces were selected as the main indicators of cutting ability. The effect of the blades on the forming chips is shown and the higher resistance of the polycrystalline diamond blades to the abrasive action of the reinforcing fibres is confirmed by microscopic photographs. Besides the confirmation of the higher durability of the diamond blades, the conditions in which when using these blades one can achieve better machining effects than the ones achievable by the compared tools are defined. Moreover, it is shown that by properly matching the machining parameters and aiding machining with oil mist lubrication, it is possible to obtain excellent surface quality by means of carbide blades. The minimum quantity lubrication also increases the life of the blades.
EN
This article presents the results of laboratory tests involving the measurement of cutting forces during the orthogonal turning of a tube made of GRADE 2 titanium alloy. The nominal diameter of the turned tube was D = 60 mm, and its wall thickness was 2.77 mm. For research purposes, a Kennametal chisel with an insert marked A3G0500M05P04DF and a holder marked A3SAR2520M0425-075-100 was used. An experimental research plan for variable cutting parameters (ƒ, νc) was developed according to the Taguchi method and statistical analysis of the results was performed using an ANOVA. Three series of tests were performed, one for each of the three different values of tube wall thickness (ap = 2.77, 1.77, 0.5 mm). In accordance with the prepared test plan, nine trials were conducted within each series. Cutting forces were measured during each test with the use of a 3-axis Kisler 9257B piezoelectric dynamometer. DynoWare computer software was used for the archiving and analysis of measurement results.
PL
Artykuł prezentuje wyniki badań laboratoryjnych pomiaru sił skrawania podczas toczenia ortogonalnego rury z tytanu GRADE 2. Nominalna średnica toczonej rury wynosiła D = 60 mm, natomiast grubość ścianki 2,77 mm. Do badań wykorzystano przecinak firmy Kennametal o oznaczeniu płytki A3G0500M05P04DF, zamontowanej w oprawce A3SAR2520M0425-075-100. Eksperymentalny plan badań dla zmiennych parametrów skrawania (ƒ, νc) opracowano według metody Taguchi, natomiast statystyczne opracowanie wyników wykonano za pomocą analizy ANOVA. W czasie prac zostały przeprowadzone trzy serie prób trzech różnych wartości grubości ścianki rury (ap = 2,77; 1,77; 0,5 mm). W ramach każdej serii zgodnie z opracowanym planem badań wykonano 9 prób. Pomiar sił skrawania był realizowany w każdej próbie za pomocą 3-osiowego siłomierza piezoelektrycznego Kisler 9257B. Do archiwizacji i analizy wyników pomiarów zastosowano program komputerowy DynoWare.
EN
The article presents the results of laboratory tests, the aim of which was to measure cutting forces during parallel turning of an AMS 5643 steel bar. The cutting trials were registered with a 3-axis Kisler 9257B piezoelectric dynamometer, and the DynoWare computer program was used to archive and analyse the results. The experimental test plan for variable cutting parameters (vc, ap, f) was created according to the Taguchi method and the statistical analysis of the results was performed using ANOVA . The work involved carrying out 9 tests with the use of an uncoated carbide cutting insert. The obtained test results will be used to specify a simulation model of the cutting process.
PL
Artykuł prezentuje wyniki badań laboratoryjnych pomiaru sił skrawania podczas toczenia wzdłużnego wałka ze stali AMS 5643. Próby skrawne rejestrowano 3-osiowym siłomierzem piezoelektrycznym Kisler 9257B, do archiwizacji i analizy wyników pomiarów zastosowano program komputerowy DynoWare. Eksperymentalny plan badań dla zmiennych parametrów skrawania (vc, ap, f) stworzono według metody Taguchi, a statystyczne opracowanie wyników wykonano za pomocą analizy ANOVA. W ramach prac zostało przeprowadzone 9 testów z zastosowaniem płytki skrwającej weglikowej niepokrywanej. Uzyskane wyniki badań będą wykorzystane do uściślenia modelu symulacyjnego procesu skrawania.
6
PL
Wyznaczono oraz przeanalizowano opory skrawania w procesie konwencjonalnego i trochoidalnego frezowania stopu aluminium 2017. Opracowano strategię obróbki i wytyczne do badań oraz zaprezentowano możliwość wykorzystania platformy pomiarowej bazującej na elementach tensometrii oporowej. Przedstawiono analizę wyników obejmujących rozkład składowych sił skrawania w procesach frezowania konwencjonalnego i trochoidalnego, realizowanych przy tych samych parametrach skrawania i tymi samymi narzędziami. Podjęto próbę interpretacji wyników.
EN
Cutting forces in the process of conventional and trochoidal milling of aluminum 2017 alloy were determined and analyzed. A machining strategy, testing guidelines and the possibility of using a measuring platform based on resistance tensometry elements were developed. The paper also presents an analysis of the results concerning the distribution of the cutting forces in the processes of conventional and trochoidal milling, carried out with the same cutting parameters and tools. An attempt was made to interpret the results.
PL
Przedstawiono badania doświadczalne, których celem było sporządzenie wykresów obrazujących wpływ kąta wyprzedzenia oraz promienia krzywizny obrabianego zarysu krzywoliniowego powierzchni złożonej na składowe siły skrawania. Przedmiotem badań doświadczalnych była wypukła oraz wklęsła powierzchnia pióra łopatki turbiny ze stopu Inconel 718. Do ich przeprowadzenia zastosowano frez toroidalny. Na podstawie wyników badań stwierdzono, że wartości kąta wyprzedzenia w obróbce wypukłej i wklęsłej powierzchni łopatki turbiny powinny być odpowiednio zmieniane w sposób ciągły wraz ze zmianą promienia krzywizny w kierunku posuwu obrabianego profilu powierzchni.
EN
Experimental studies are presented, were conducted that aimed at determining the mathematical models of the influence of the lead angle and the radius of curvature of the profile of machined sculptured surface on the components of the cutting force. The object of the experimental studies was a convex and concave surface of a turbine blade of Inconel 718 alloy. The toroid cutter was used for the tests. Based on the results of the study it was found that the lead angle in the machining of the convex surface and concave turbine blade should be continuously varied with the change of radius of curvature in the direction of the machined surface profile.
PL
Przedstawiono analizę wpływu geometrii wiertła krętego, a zwłaszcza kąta 2κr, na siły skrawania podczas wiercenia otworów w elemencie wykonanym ze stopu aluminium do obróbki plastycznej EN AW-2024. Dodatkowo badano wpływ zastosowania korekcji geometrii wiertła na wartości sił skrawania. W trakcie prób mierzono wartości składowych Fx, Fy i Fz siły skrawania dla narzędzi o różnej geometrii, przy założonych, zmiennych parametrach technologicznych, tj. posuwie f i prędkości skrawania vc. Szczegółowej analizie poddano zmiany wartości składowej osiowej Fz. Stwierdzono, że stosowanie wierteł z kątem 2κr < 100° jest niekorzystne ze względu na znaczną wartość siły osiowej Fz oraz jej dużą amplitudę. Również brak korekcji wiertła przekłada się na wzrost wartości siły osiowej Fz i jej amplitudy.
EN
The paper presents the analysis of the influence of the twist drill geometry, in particular the 2κr angle, on the cutting forces during holes drilling in the element made of aluminum alloy for plastic forming EN AW-2024. In addition, the impact of the application of the drill geometry correction on the values of cutting forces was also investigated. During the tests, the values of components Fx, Fy and Fz of the cutting force for tools with different geometry with the set, variable technological parameters, i.e.: feed f and cutting speed vc were measured. The changes in the value of the axial component Fz were analyzed in detail. It was found that the use of drills with an angle of 2κr < 100°, due to the significant value of the axial force Fz and high amplitude is unfavorable. Also, the lack of drill correction translates into an increase in the value of the axial force Fz and its amplitude.
9
Content available remote Reducing of process model uncertainty towards smart machining systems
EN
This paper presents an approach of empirical modeling of cutting process physical phenomena with measurement uncertainty parameters accompanied to the model exponents/ /coefficients. The approach is presented trough an example of creating a power mathematical model for average cutting temperature in turning with details about the uncertainty contributions from different experimental plans. The approach is proposed to be implemented as usual practice during empirical modeling, in order the resulting models to fit with the needs of the smart machining systems and the needs of interoperability between researchers.
PL
W pracy przedstawiono propozycję modelowania empirycznego zjawisk fizycznych w skrawaniu z uwzględnieniem parametrów niepewności pomiarowej oraz modelowych współczynników. Propozycję tę zaprezentowano na przykładzie modelu matematycznego temperatury skrawania, z podaniem danych dotyczących składowej niepewności z różnych planów eksperymentalnych. Postuluje się wdrożenie tego podejścia podczas modelowania empirycznego, tak aby otrzymane modele odpowiadały potrzebom inteligentnych systemów obróbki skrawaniem oraz potrzebom interoperacyjności między naukowcami.
PL
Przeanalizowano siły skrawania przy frezowaniu współbieżnym i przeciwbieżnym odlewniczego stopu aluminium AlSi10Mg. Badania obejmowały pomiar składowych Ff, Fp i Fc (odpowiednio: Fx, Fy, Fz) siły skrawania oraz wyznaczenie ich amplitud przy stałej wartości posuwu na ostrze fz oraz przyjętych zmiennych parametrach technologicznych, tj.: głębokości skrawania ap, szerokości frezowania ae oraz prędkości skrawania vc. Na podstawie uzyskanych wyników stwierdzono, że wraz ze wzrostem głębokości skrawania i szerokości frezowania wartości wybranych składowych i ich amplitudy rosną zarówno dla frezowania współbieżnego, jak i przeciwbieżnego. Przy wzroście prędkości skrawania zaobserwowano, że składowe całkowitej siły skrawania rosną do prędkości vc = 450 m/min, następnie ich wartości zaczynają spadać. Jest to związane z przejściem z obróbki konwencjonalnej w zakres high speed cutting. Warto podkreślić, że w przypadku frezowania przeciwbieżnego odnotowano wyższe wartości sił skrawania niż dla frezowania współbieżnego.
EN
The analysis of cutting forces during in-cut and out-cut milling of EN AC-AlSi10Mg cast aluminum alloy was presented. The research included measurement of the components of the total cutting force: Ff, Fp and Fc (Fx, Fy, Fz respectively) and determination of their amplitudes at a constant feed per tooth value and the adopted variable technological parameters, i.e.: depth of cut ap, milling width ae and cutting speed vc. Based on the obtained results, it was found that along with the increase in the depth of cut and the milling width, the values of selected components and their amplitudes increase for both in-cut and out-cut milling. During rise of cutting speed, it was observed that the components of the total cutting force increase to the speed vc = 450 m/min, then their values begin to decrease. This is related to the transition from conventional machining to the range of High Speed Cutting. It is important that higher values of cutting forces were noted in the case of out-cut milling instead of in-cut milling.
EN
One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process, the technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. It is crucial to find a suitable solution which will meet the requirements as well as the work conditions of a given machine part. The article presents the results of influence of change of cutting parameters on temperature and cutting forces during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal CDS 6250 BX-1000 centre lathes. Measurement of cutting forces during turning process used DKM 2010 turning dynamometer. A cutting tool conducted the turning process with CCET09T302R-MF insert by DIJET. During the turning, the following machining parameters were used: cutting speed Vc = 226 m/min, feed f = 0.044; 0.062; 0.083; 0.106 mm/rev and cutting depth ap = 0.375; 0.625; 0.875 mm. The chemical composition of steel was measured by Solaris-ccd plus optical spectrometer. The Smartzoom 5 microscope made the view of the nose radius of cutting tool.
EN
One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process, the technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. It is crucial to find a suitable solution which will meet the requirements as well as the work conditions of a given machine part. The article presents the results of influence of cutting parameters change on temperature and cutting forces during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal CDS 6250 BX-1000 centre lathe. Measurement of cutting forces during lathing process used DKM 2010 turning dynamometer. The turning process was conducted by a cutting tool with CCET09T302R-MF insert by DIJET. During the turning, the following machining parameters were used: cutting speed Vc = 152, 219, 304 m/min, feed f = 0.044, 0.062, 0.083 mm/rev and cutting depth ap = 0.4, 0.8, 1.2, 1.6 mm. The view of the nose radius of cutting tool before and after the turning process was made by the Smartzoom 5 microscope.
PL
Jednym z najważniejszych problemów współczesnych technik wytwarzania jest zapewnienie odpowiedniej jakości wyrobu, przy minimalizacji kosztów i jednoczesnym wzroście wydajności produkcji. Podczas obróbki wykończeniowej nadawane są ostateczne wymiary i właściwości użytkowe danego elementu. W artykule przedstawiono wyniki badań wpływu zmiany warunków obróbki na wartość sił podczas toczenia wałów wykonanych ze stali nierdzewnej. Badania przeprowadzono na wałku o średnicy 59 mm wykonanego ze stali nierdzewnej X5CrNi18-10. Proces toczenia czopów wału przeprowadzono na tokarce uniwersalnej kłowej CDS6250BX-1000. Podczas badań wykorzystano nóż tokarski z wymiennymi płytkami skrawającymi CCMT09T302WF, CCMT09T304WF oraz CCMT09T308WF. Pomiar sił skrawania podczas toczenia wykonano siłomierzem DKM 2010.
EN
One of the greatest problem of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. During finish treatment the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The paper presents the results of influence of changing treatment conditions on the value of the cutting forces during cutting process. The turning process of shaft pins ? 59 mm in diameter, made of X5CrNi18-10 stainless steel was carried out on a CDS6250BX-1000 universal lathe. The turning process was conducted by a cutting tool with CCMT09T302WF, CCMT09T304WF and CCMT09T308WF replacable inserts. The measurement of cutting forces during turning was recorded using a DKM 2010 dynamometer.
14
Content available remote Inteligentna strategia frezowania naroży ze stopów tytanu
PL
Frezowanie materiałów trudno skrawalnych wiąże się z wpływem sił skrawania na odkształcenia zarówno narzędzia, jak i przedmiotu obrabianego. Zastosowanie inteligentnych strategii pozwoli na uzyskanie żądanych dokładności wymiarowo-kształtowych. Do materiałów trudno skrawalnych zaliczamy stop Ti6Al4V, stosowany chętnie w medycynie i przemyśle lotniczym.
EN
Milling of difficult-to-machine materials implies the influence of the cutting forces on the deformation of both a tool and a workpiece. The use of intelligent strategies allows to achieve the desired accuracy of the dimension and shapes. Difficult-to-machine materials include Ti6Al4V, willingly used in medicine and the aerospace industry.
EN
Research in 60s and 70s started to deal with the shape of the chip characterization. It was possible then to do a limited study by means of measuring tool park. During such a study, different models for chip formation became familiar, such as the Time or Merchant model. The aim of article is to gain insight into some accompanying phenomena, occurring while cutting of different materials and with various tools. During an experimental design, the possible effects of different variables on each other and individually were considered. Two work-pieces (C45, POM) with two inserts (with two different edge design) were tested while changing of cutting speed and feed. During measurements cutting forces at 5000 Hz signal reception were tested or the evolution of cutting temperature at different experimental settings was evaluated. The chip characteristics are measured by a high speed camera. The camera is connected with PC for recording and controlling the experimental procedure in real-time. The frequency of High Speed Camera was similar than the frequency of the cutting force measuring system. This similarity is provided with the system set-up synchronization.
EN
The purpose of this article was to evaluate the significance of the influence of five- axis orientation parameters of a toroidal cutter axis and the geometrical parameters of the machined sculptured surface on the intersection of the cut layer in a 5-axis machining. An impact assessment was performed by simulating concave-convex and convex-concave surfaces using a discrete method of direct transformation in a CAD environment. It was shown that only the radius of curvature of the surface in the feed direction and the angle of the tool axis affected the change in the intersection of the cutting layer. Subsequently, experimental tests were conducted that aimed at determining the mathematical models of the influence of these important parameters on the components of the cutting force. The object of the experimental studies was a convex and concave surface of a turbine blade of Inconel 718 alloy. The R300-016B20L-08L Sandvik Coromant toroid cutter was used for the tests. Based on the results of the study it was found that the lead angle in the machining of the convex surface and concave turbine blade should be continuously varied with the change of radius of curvature in the direction of the machined surface profile.
17
Content available Accuracy analysis of the micro-milling process
EN
Machining errors can be caused by various factors, such as thermal deformations of milling machine, drives and milling machine accuracy, tool run out, tool deflections during the machining process, and workpiece setup errors. The main purpose of this paper is to determine and compare machining errors of a Kern Pyramid Nano milling machine and a prototype micro milling machine built at West Pomeranian University of Technology in Szczecin. Since not all of the errors can be measured with specialized measurement equipment, a milling experiment of a complex part with various geometrical features was performed. Machining errors can change in time due to thermal deformations; therefore, the milling experiment was performed on a cold machine and for machine after a warm up procedure. In order to avoid workpiece set up errors, the workpiece surface was first milled before machining. The influence of tool run out and tool deflections were neglected. Major factors that affect the milling process are both the machine and drive accuracy. During the milling experiment, cutting forces were recorded. The machined sample was measured in order to compare machining errors with the reference geometry.
PL
Błędy obróbki skrawaniem mogą być spowodowane różnymi czynnikami takimi jak: odkształcenia termiczne obrabiarki, dokładność napędów oraz obrabiarki, bicie osiowe narzędzia, odkształcenia narzędzia podczas obróbki oraz błędy ustawienia przedmiotu obrabianego. Głównym celem prezentowanego artykułu jest określenie i porównanie błędów obróbki precyzyjnej frezarki Kern Pyramid Nano oraz prototypowej mikrofrezarki zbudowanej w Zachodniopomorskim Uniwersytecie Technologicznym w Szczecinie. Nie wszystkie błędy frezarki mogą być zmierzone za pomocą wyspecjalizowanej aparatury pomiarowej. Z tego względu zdecydowano się wykonać frezowanie części o złożonej geometrii. Błędy obróbki mogą zmieniać się w czasie z powodu odkształceń termicznych obrabiarki. Z tego względu eksperyment mikrofrezowania wykonano zarówno dla maszyny zimnej, jak i dla maszyny po procedurze rozgrzewania jej. Aby uniknąć błędów ustawienia przedmiotu obrabianego, powierzchnia przedmiotu obrabianego została najpierw przefrezowana. Wpływ bicia osiowego oraz odkształceń narzędzia podczas obróbki został pominięty. Głównym czynnikiem, który wpływa na dokładność obróbki, to dokładność obrabiarki oraz dokładność napędów. Podczas eksperymentu rejestrowano siły skrawania. Obrobiona próbka została zmierzona, aby porównać błędy obróbki z geometrią odniesienia.
EN
One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process, the technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. It is crucial to find a suitable solution which will meet the requirements as well as the work conditions of a given machine part. The article presents the results of influence of change of cutting parameters on temperature and cutting forces during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal CDS 6250 BX-1000 centre lathes. Measurement of cutting forces during lathing process used DKM 2010 turning dynamometer. The turning process was conducted by a cutting tool with CCET09T302R-MF insert by DIJET. During the turning, the following machining parameters were used: cutting speed Vc = 226 m/min, feed f = 0.044, 0.062, 0.083, 0.106 mm/rev and cutting depth ap = 0.25, 0.5, 0.75, 1.0 mm. The chemical composition of steel was measured by Solaris-ccd plus optical spectrometer.
EN
Carbon fiber reinforced polymeric (CFRP) composite materials are widely used in aerospace, automobile and biomedical industries due to their high strength to weight ratio, corrosion resistance and durability. High speed machining (HSM) of CFRP material is needed to study the impact of cutting parameters on cutting forces and chip microstructure which offer vital inputs to the machinability and deformation characteristics of the material. In this work, the orthogonal machining of CFRP was conducted by varying the cutting parameters such as cutting speed and feed rate at high cutting speed/feed rate ranges up to 346 m/min/ 0.446 mm/rev. The impact of the cutting parameters on cutting forces (principal cutting, feed and thrust forces) and chip microstructure were analyzed. A significant impact on thrust forces and chip segmentation pattern was seen at higher feed rates and low cutting speeds.
EN
The article presents achieved results of research focused on the influence of various factors modification on cutting forces at longitudinal turning of steel C 45 using two tools with different shape and geometry at constant values of feed and depth of cut. The individual components of cutting force were compared reciprocally, i. e. axial, radial, tangential and finally resulting cutting force depending on cutting speed.
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