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1

Simulation of the influence of cutting speed and feed rate on tool life in hard turning of AISI 4140 steel

Paengchit Phacharadit, Saikaew Charnnarong

Materials Science Poland

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2023

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Vol. 41, No. 2

311--324

EN

Tool life performances of Al2O3+TiC and TiN+AlCrN tool inserts were investigated experimentally under different cutting conditions in turning AISI 4140 steel. The tool life model is defined in accordance with a maximum surface roughness of 0.8 μm for the tool life criterion. The relationships between machining factors (i.e., cutting speed and feed rate) and tool life were obtained by Taylor’s formular. The sensitivity of cutting speed and feed rate to tool life was evaluated by Monte Carlo simulation. The results showed that turning with high cutting speeds and feed rates decreased the tool life of both inserts. At different cutting speeds and feed rates, Al2O3+TiC exhibited better tool life performance than TiN+AlCrN. In addition, the simulation results indicated the average tool life of Al2O3+TiC was approximately 40% greater than that of TiN+AlCrN by varying cutting speeds below and above the cutting speed of 220 m/min while keeping the feed rate constant at 0.06 mm/rev. Similarly, when keeping the cutting speed constant at 220 m/min, the average tool life of Al2O3+TiC was approximately 45% greater than that of TiN+AlCrN by varying feed rates below and above the feed rate of 0.06 mm/rev. Variations of tool life values by varying cutting speeds were more sensitive than those by varying feed rates for both tool inserts.

2

Influence of cutting parameters on the performance of plough during hard rock cutting in coal mining

Palaniappan Sathish Kumar, Chinnasamy Moganapriya, Pal Samir Kumar, Rathanasamy Rajasekar

Journal of Sustainable Mining

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2023

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Vol. 22. iss. 3

185--194

EN

Coal ploughs have proved very successful on many faces in various parts of the world. Recently, there has been a general tendency in longwall working to increase the speed at which the machine progresses along the coal face. An increase in production rate demands enhances either due to depth of penetration or cutting speed. This, in turn, results in increasing power demand and also the force acting on an individual pick. To get maximum efficiency from a cutting machine, a number of parameters need to be investigated. The first and foremost thing of interest is naturally the pick geometry. The cutting force can be expected to depend mainly on the rack angle and clearance angle of the tool. The second parameter is the cutting depth, which when enhanced, increases the rate of advancement and, at the same time, results in enhanced cutting force. This results in large power demand and increases wear of picks. Thirdly, cutting speed, in which higher cutting speed will increase the production rate but at the same time is expected to enhance the power demand and the cutting force. This paper aims at investigating the cutting efficiency of the plough by simulating the coal cutting operation in the laboratory. The effect of three main parameters like pick geometry, cutting depth, and cutting speed, on cutting efficiency have been studied in detail. The cutting force elevates at a faster rate with an increase in depth at higher speeds. The percentage increase in force is nearly 20% for a speed increase of 20%.

3

Evaluation of the roundness quality of galvanized steel plate due to variations in cutting speed and nozzle diameter during the laser cutting

Aulia U., Akhyar Akhyar

Journal of Achievements in Materials and Manufacturing Engineering

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2023

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Vol. 118, nr 2

62--68

EN

Purpose Generally, laser cutting processes aim to cut materials with high accuracy, as well as precise and near-perfect sizes and results. The purpose of this study is to evaluate the roundness quality of the holes cut by laser cutting on galvanised steel plates; two variations are given, such as cutting speed and nozzle diameter. Design/methodology/approach The type of laser used is a fibre laser. The material used is galvanized steel with a thickness of 3 mm with dimensions of 200 mm in length and 200 mm in width. A round profile is good if the distance between the points of the geometric shape is the same distance from the centre point. Findings The measurement results show that the smallest radius deviation is with an average value of 20.08 mm at a nozzle diameter of 2.5 mm and a cutting speed of 3 m/min, close to the initial radius value of 20.00 mm. Research limitations/implications During the laser cutting process, The best roundness quality is the combination of a nozzle diameter of 2.5 mm and a cutting speed of 3 m/min with a small deviation (the index deviation is 0.4%). At the same time, the biggest deviation in this experiment is the combination of parameters with a nozzle diameter of 3 mm and a cutting speed of 4 m/min (the maximum deviation value is 1%). Practical implications The use of the proposed nozzle diameter and cutting speed approach is an important requirement for industrial applications with laser cutting to get the right product for its intended use. Originality/value This article presents different nozzle diameters and cutting speeds to reveal the roundness quality due to these variations, where the roundness quality will be adapted for a particular application.

4

Określenie korelacji między prędkością skrawania a parametrem chropowatości Ra

Jędrzejczyk Dariusz, Mikołajczyk Jarosław Robert

Obróbka Metalu

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2022

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nr 3

11--15

PL

W pracy przedstawiono zagadnienia dotyczące określenia zależności matematycznej pomiędzy prędkością skrawania, a parametrem chropowatości Ra. Wykazano, że istnieje silna ujemna korelacja między w/w badanymi zmiennymi.

EN

In this paper investigations concerning the determination of the mathematical relationship between the cutting speed and the roughness parameter Ra were presented. A strong negative correlation between the studied variables was demonstrated.

5

Characterization of residual stresses induced into bearing rings by means of soft turning using different turning parameters

Zaghal Jawad, Mertinger Valeria, Filep Adam, Varga Gyula, Benke Marton

Journal of Machine Engineering

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2021

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Vol. 21, No. 4

49--56

EN

Residual stresses are those stresses which remain in solid materials after removing the external load. Residual stresses which are induced by machining processes play important role in determining the service life of the machined components, depending on its magnitude, sign, and direction. This research provides a comprehensive correlation between three turning parameters and the resulting residual stresses formed on the surface of the outer ring of tapered roller needle bearing, made of 100CrMnSi6-4 type steel. The examined parameters were cutting speed, feed and tool nose radius. Radial and axial residual stresses on the surface were measured using sample cutting-free X-ray diffraction method. It is shown that the effect of one processing parameter can even be opposing depending on the other parameters. Thus, the effects of turning parameters on residual stresses must be examined in a comprehensive manner.

6

Wielokryterialna optymalizacja programów sterujących na obrabiarki CNC poprzez korektę wartości wybranych parametrów procesu skrawania. Cz. 1,Techniczne aspekty korekty wybranych parametrów technologicznych w programach sterujących na obrabiarki sterowane numerycznie

Jarosz Krzysztof, Krok Marek, Niesłony Piotr

Stal, Metale & Nowe Technologie

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2019

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nr 9-10

70--74

PL

W artykule poruszono zagadnienia dotyczące wybranych aspektów technicznych związanych z korektą wartości wybranych parametrów skrawania w programach sterujących dla obrabiarek CNC. Przedstawiono zagadnienia problemowe oraz wyróżniono obszary wymagające szczególnej uwagi przy korekcie wartości parametrów skrawania niezbędne do zapewnienia prawidłowej pracy obrabiarki oraz uniknięcia kolizji i uszkodzeń narzędzi skrawających. Przedstawiono również schemat ideowy opisujący podstawowe założenia dla autorskiego oprogramowania.

EN

Technical aspects of modifying values of selected process parameters in CNC toolpaths are described in this paper. Problem areas and issues that need special attention to ensure correct machine tool operation, collision avoidance and prevention of tool breakage are identified. A flowchart presenting the basic operating principles of an original software is also presented.

7

The effect of changes in depth of cut and cutting speed of CNC toolpaths on turning process performance

Jarosz K., Niesłony P., Löschner P.

Archives of Mechanical Technology and Materials

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2018

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Vol. 38

40--44

EN

In this article, a novel approach to computer optimization of CNC toolpaths by adjustment of cutting speed vcand depth of cut apis presented. Available software works by the principle of adjusting feed rate on the basis of calculations and numerical simulation of the machining process. The authors wish to expand upon this approach by proposing toolpath optimization by altering two other basic process parameters. Intricacies and problems related totheadjustment of apand vcwere explained in the introductory part. Simulation of different variant of the same turning process with different parameter values were conducted to evaluate the effect of changes in depth of cut and cutting speed on process performance. Obtained results were investigated on the account of cutting force and tool life. The authors have found that depth of cut substantially affects cutting force, while the effect of cutting speed on it is minimal. An increase in both depth of cut and cutting speed affects tool life negatively, although the impact of cutting speed is much more severe. An increase in depth of cut allows for a more significant reduction of machining time, while affecting tool life less negatively. On the other hand, the adjustment of cutting speed helpsto reduce machining time without increasing cutting force component values and spindle load.

8

Influence of selected cutting conditions on cutting forces

Görög Á., Stančeková D., Kapustová M., Görögová I., Miturska I.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 1

179--185

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.

9

Analiza wpływu prędkości skrawania na odkształcenia po frezowaniu elementów cienkościennych wykonanych ze stopu EN AW-2024

Kuczmaszewski J., Pieśko P., Zawada-Michałowska M.

Mechanik

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2016

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R. 89, nr 8-9

1066--1067

PL

Przeanalizowano wpływ prędkości skrawania vc na wielkość odkształceń powstających po frezowaniu elementów cienkościennych wykonanych ze stopu aluminium EN AW-2024. W wyniku obróbki skrawaniem w warstwie wierzchniej generowany jest określony stan naprężeń własnych. Przy obróbce elementów cienkościennych może to powodować ich odkształcenia postaciowe, a w konsekwencji – niedopuszczalne błędy geometryczne. W badaniach skoncentrowano się na wpływie na te odkształcenia obróbki wykończeniowej, przeprowadzonej z istotnie różną prędkością skrawania, to jest dla vc = 200 m/min oraz vc = 1200 m/min. Zaobserwowano wzrost odkształcenia wraz ze wzrostem prędkości skrawania vc.

EN

Analysed is the cutting speed vc influence on the value of thin-walled elements deformation made of aluminium alloy EN AW-2024 after milling. As a result of machining, a specific state of residual stresses in the surface layer is generated. During machining of thin-walled elements, it may make of non-dilatational strain of parts and consequently unacceptable geometric errors. The focus of the study was to determine finishing operation influence on this deformation, which was performed in significantly different values of cutting speed, that is for vc = 200 m/min and vc = 1200 m/min. It has been observed that the deformation enlarged with the increase of cutting speed vc.

10

Теоретические основы виброрезкиарматурных стержней

Evtukov S. A., Rajczyk J., Tavliarov I.

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2014

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Z. 20 (170)

48--54

EN

The paper presents the study of relationships on shear strength of the cutting speed. Tests were performed for three speeds: 5, 33 and 120 rpm knife shaft. A mathematical formula for calculating the deformation of crushing and providing sufficient practical accuracy was proposed.

11

Evaluation of the cutting edge fan-shaped during the cutting process by the hydro abrasive water jet

Šúň R., Spišák E.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2012

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z. 84[284], nr 4

47--58

EN

This article presents the current state of hydro-erosion cutting and factors affecting the quality of cutting surface. The aim of this article is the evaluation of the fanshaped water spray pattern on the bottom cut edge by the hydro-erosion cutting based on selected parameters like cutting surface roughness and the distance between the inlet and outlet water jet. The results demonstrate that cutting speed had the largest influence on evolution of fan-shaped bottom of the cut edge because increasing cutting speed increases the values of both parameters mentioned above.

PL

Artykuł przedstawia bieżący stan wiedzy na temat erozyjnego cięcia strumieniem wody oraz prezentuje wskaźniki, które wpływają na jakość powierzchni przecięcia. Celem artykułu jest ocena wachlarzowatości dolnej krawędzi powierzchni przecięcia na podstawie wybranych parametrów, takich jak chropowatość powierzchni przecięcia i odległość pomiędzy wlotem i wylotem strumienia wody. Wyniki badań wskazują, że prędkość cięcia ma największy wpływ na rozwój wachlarzowatości dolnej krawędzi powierzchni przecięcia, ponieważ zwiększenie prędkości cięcia zwiększa wartość obu wymienionych parametrów.

12

Effect of the cutting speed on the chip morphology and the cutting forces

Daymi A., Boujelbene M., Ben Salem S., Hadj Sassi B., Torbaty S.

Archives of Computational Materials Science and Surface Engineering

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2009

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Vol. 1, nr 2

77-83

EN

Purpose: The aim of this research is to make a first experimental analysis of the effect of the cutting speed on the chip morphology, and of the cutting forces in the orthogonal turning process of the titanium alloys Ti-6Al-4V. Design/methodology/approach: The methodology has consisted of proving a series of parameters combinations: f, feed rate, Vc, cutting speeds are explored in a range from 50 to 250 m/min, and is analyzing the different types of chips and the evolution cutting forces appeared during each one them, and determined the analytical model of plastic deformation ratio. Findings: Tests achieved have shown three main types of chips: Continuous chip at 50 m/min, Flow chip for speeds ranging around 100 m/min, and Shear localized chip starting from the transition speed of 125 m/min and above. The modification of the mechanism of chip formation is associated with the appearance of shearing instability. Chip segmentation by shear localisation is an important process which is observed within a certain range of cutting speeds. This phenomenon might be desirable in reducing the level of the cutting forces by improving chip's evacuation. Research limitations/implications: A possible future work would be the development of a general the phenomenal of the thermo mechanical of the cutting high speed machining. The behavior is of the thermo - visco - plastic studies are planed in the future. Practical implications: The relationship found between high speed machining and chip morphology and the cutting forces and work piece surface finish has an important practical implication since it allows selecting the best cutting condition combination from the points of view both the security and the economy for the established requirements in each case. Results are of great importance in for aerospace, biomedical and automotive industry. Originality/value: The paper is original since the bibliographical review has allowed testing that, although works about these themes exist, none approaches the problem like it has been made in work.

13

Determination of laser cutting speed based on energy balance

Radovanovic M.

Tribologia

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2002

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nr 6

1561-1570

EN

Technological problems faced in the field of laser machines' application to contour sheet cutting lie in insufficient knowledge of the laser technique in addition to the absence of both sufficiently reliable practical data and knowledge about the parameters affecting the work process itself. Significant parameter which it is necessary to determine and to enter in NC--program is cutting speed. Numerical value of cutting speed can determine based on recommendation of manufacturers, peculiar experience or by aid of equations from literatures. In paper it is determined equation for laser cutting speed based on energy balance.

PL

Problemy technologiczne związane z zastosowaniem cięcia laserowego w obszarze konturowego cięcia arkuszy wynikają z niewystarczającej wiedzy o technice cięcia laserowego w powiązaniu z brakiem wystarczających, wiarygodnych danych praktycznych oraz wiedzy o czynnikach wpływających na ten proces. Podstawowym parametrem, który należy określić jest prędkość cięcia. Wartości liczbowe prędkości cięcia można określić bazując na wytycznych dostawcy urządzenia, własnego doświadczenia lub obliczyć za pomocą równań podanych w literaturze. W artykule podano równanie określające prędkość cięcia laserem oparte o bilans strat energetycznych.

14

Investigations into the cutting properties of ceramic tools type TA-Z in face milling of steel 45.

Lubecka Elżbieta, Lubecki Paweł

Advances in Manufacturing Science and Technology

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2001

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Vol. 25, nr 3

51-59

EN

The paper presents results of the research on the cutting properties of ceramic tools (TA-Z) in face milling of steel 45. Roughness of the machined surface Ra and periodical cutting speed Vc15 were assumed to be the machinability rating for the tested tools. It was shown that ceramic tools type TA-Z have good cutting properties, which results in low surface roughness and high periodical cutting speed Vc15. The tools demonstrate good cutting properties also in the conditions of interrupted machining (face milling). No case of catastrophic failure was observed. The predominant mechanism of tool wear is the one of abrasive wear.

PL

W pracy przedstawiono wyniki badań właściwości skrawnych ostrzy ceramicznych gatunku TA-Z podczas frezowania czołowego stali 45. Za wskaźniki skrawalności badanych ostrzy przyjęto chropowatość powierzchni obrobionej, określonej parametrem Ra oraz okresową prędkość skrawania Vc15. Wykazano, że ostrza ceramiczne gatunku TA-Z mają dobre właściwości skrawne, umożliwiające osiąganie małej chropowatości powierzchni obrobionej i dużej wartości okresowej prędkości skrawania Vc15. Ostrza te mają dobre właściwości skrawne w warunkach obróbki przerywanej (frezowanie czołowe). W przeprowadzonych badaniach nie stwierdzono, żadnego przypadku katastroficznego zużycia ostrza. Dominującym mechanizmem zużycia ostrzy jest mechanizm zużycia ściernego.

15

Powłoki węglowe i diamentopodobne /DLC/ formowane dwuwiązkową metodą IBAD w zastosowaniach na ostrza narzędzi skrawających do obróbki HSM.

Wantuch E., Rajchel B., Burakowski T.

Inżynieria Materiałowa

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1999

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R. XX, nr 5

318-321

PL

W artykule przedstawiono analizę przyczyn zużywania sie ostrzy narzędzi z węglików spiekanych w szerokim zakresie prędkości skrawania od ok. 20m/min do blisko 1000m/min, stosowanych przy obróbce High Speed Cutting. Na podstawie analizy literatury wykazano, że w zakresie prędkości skrawania powyżej 250m/min dominujacą formą zużycia węglików spiekanych jest dyfuzja W, Ti oraz Co do obrabianego przedmiotu. W prezentowanej pracy podjęto próbę wytworzenia powłok DLC na podłożu monokryształu krzemu i materiale endoprotezy stawu biodrowego celem wstępnej oceny cech mechanicznych formowanych powłok. Badania odporności na zużycie ścierne wytworzonych powłok wykazują ich wzrost odporności na zużycie w porównaniu z badaniami zużycia podłoża. Stwierdzono bardzo duży wpływ późniejszego wygrzewania formowanych powłok w próżni w temperaturze z zakresu od 823 K do 923 K na przyrost odporności na zużycie ścierne.

EN

The article presents the analysis of reason for wear of tool blades made of sintered carbides in a wide range of cutting speed from c.a. 20m/min to speeds close to 1000m/min, used at High Speed Cutting machining. On the basis of available sources analysis, it was proved that within the cutting speed above 250m/min a dominating form of sintered carbides wear is diffusion of W, Ti and Co to the machined object. The presented work undertakes the attempt to produce DLC coatings on a silicon monocrystal substrate and the hip joint endoprosthesis material in order to conduct a preliminary assessment of mechanical features of formed coatings. The research in abrasive wear resistance of formed coatings indicates on their increase in the wear resistance in comparison to substrate wear tests. The research revealed a very large influence of further heating of formed coatings in vacuum at the temperature ranging from 823 K to 923 K upon the increase in abrasive wear resistance.