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1

An Attempt to Model the Main and Normal Cutting Forces Dependencies between Cutting Parameters and Some Strength Properties of Wood by Flat Longitudinal Cutting

Porankiewicz Bolesław

Computational Methods in Science and Technology

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2022

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Vol. 28, No. 1

27--35

EN

This paper evaluates multi-factor, non-linear dependencies of main (F C ) and normal (trust) (F N ) cutting forces, from chip thickness (ap), rake angle (γF ) and some strength properties, namely the compression strength parallel to wood fibers (RC∥), tensile strength perpendicular to wood fibers (RT ⊥), shearing strength parallel to wood fibers (RS∥) and bending strength (RB), for three North American wood species (analyzed altogether), by opened, flat, longitudinal cutting and very low cutting speed, based on work [1]. In the analyzed relations, several strong interactions were evidenced, graphically illustrated and discussed. Although a wood density (D) and a moisture content (mc), were not taken into account in this study, very good fit was obtained. The lowest influence of the RC∥ on the F C and the F N cutting forces was observed.

2

Badania wpływu grubości warstwy skrawanej i cieczy obróbkowej na kształt wiórów w procesie skrawania ortogonalnego

Bławucki S., Zaleski K.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2017

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z. 89 [295], nr 3

285--294

PL

Artykuł prezentuje sposób powstawania wiórów dla wybranych stopów metali nieżelaznych z zastosowaniem specjalnego stanowiska do skrawania ortogonalnego. W pracy przeprowadzono pomiary wizyjne strefy skrawania z wykorzystaniem kamery do obserwacji zjawisk szybkozmiennych, w celu analizy etapów procesu kształtowania się wióra. Dokonano identyfikacji kształtu powstałych wiórów przy skrawaniu ortogonalnym i zmiennej grubości warstwy skrawanej z użyciem cieczy smarujących oraz w warunkach skrawania bez smarowania. Wyniki badań mogą służyć do weryfikacji i walidacji modeli numerycznych skrawania ortogonalnego stopów metali nieżelaznych.

EN

This article presents the method of chip formation for selected non-ferrous metal alloys using a special device for orthogonal cutting. To analyze the stages of the chip forming process the measurements of cutting zone were carried out using a video camera for recording quick-change phenomena. The shape of chips formed at orthogonal cutting was determined for the variable depth of cut and under fluid lubrication and dry cutting conditions. The results of research can be used to verify and validate numerical models of orthogonal cutting of non-ferrous metal alloys.

3

Application of PIV method to study the speed distribution of oil mist particles in the orthogonal cutting process

Wójcik R., Stachurski W.

Journal of Mechanical and Energy Engineering

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2017

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Vol. 1, No 1

51--55

EN

The paper presents the use of the PIV method in experimental studies on the speed distribution of oil particles contained in oil mist delivered into a cutting zone with minimum quantity (MQL). During investigations an orthogonal sample was of an aluminum alloy PA7N was machined using HS18-0-1 high-speed steel cutter. The oil mist was delivered into the cutting zone by a single spray nozzle directed at the tool rake surface. Two angular settings of the spray nozzle were applied in relation to the surface of the machined sample. Based on the images obtained by the PIV method, the distribution of the oil particles in the cutting area was determined according to the setting the spray nozzle. Studies have indicated more favorable conditions for the delivery of oil mist at the angle of spray nozzle at 85°. These conclusions were confirmed by measuring the cutting force in tangential direction to the machined surface.

4

Finite element analysis of influence of flank wear evolution on forces in orthogonal cutting of 42CrMo4 steel

Madajewski M., Nowakowski Z.

Archives of Mechanical Technology and Materials

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2017

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Vol. 37

58--64

EN

This paper presents analysis of flank wear influence on forces in orthogonal turning of 42CrMo4 steel and evaluates capacity of finite element model to provide such force values. Data about magnitude of feed and cutting force were obtained from measurements with force tensiometer in experimental test as well as from finite element analysis of chip formation process in ABAQUS/Explicit software. For studies an insert with complex rake face was selected and flank wear was simulated by grinding operation on its flank face. The aim of grinding inset surface was to obtain even flat wear along cutting edge, which after the measurement could be modeled with CAD program and applied in FE analysis for selected range of wear width. By comparing both sets of force values as function of flank wear in given cutting conditions FEA model was validated and it was established that it can be applied to analyze other physical aspects of machining. Force analysis found that progression of wear causes increase in cutting force magnitude and steep boost to feed force magnitude. Analysis of Fc/Ff force ratio revealed that flank wear has significant impact on resultant force in orthogonal cutting and magnitude of this force components in cutting and feed direction. Surge in force values can result in transfer of substantial loads to machine-tool interface.

5

Investigation of Initial Wear Period of Differently Coated Carbide Cutting Tools

Bartoszuk M., Grzesik W.

Journal of Machine Engineering

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2015

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Vol. 15, No. 4

37--45

EN

In this paper the results of experimental studies concerning the phenomenon of initial period of the wear of differently coated sintered carbide tools when dry orthogonal cutting of an AISI 321 austenitic stainless steel are presented. The motivation for this study results from the lack of technological guides concerning the optimal choice of coated cutting tools for machining of corrosion resistant austenitic stainless steels. A number of cutting tool inserts with the plane rake face made of a fine H10F sintered carbide substrate with specially deposited TiN, including TiCN, TiAlN, AlTiN and AlCrN single layers were used in wear tests. Both rake and flank faces of the cutting inserts were examined by optical and confocal microscopy after controlled tool wear. The possible wear mechanisms in terms of changes of the tool-chip contact were investigated.

6

Effect of tool model on result of finite element simulation of high speed machining

Markopoulos A. P., Habrat W., Galanis N. I., Karkalos N. E.

Advances in Manufacturing Science and Technology

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2015

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Vol. 39, nr 4

23--35

EN

The finite element method has been extensively used for the simulation of manufacturing processes and especially machining. In this paper, finite element models of high speed machining are presented. More specifically, orthogonal and oblique cutting models are presented, where the geometrical and material properties of the cutting tool are investigated. Orthogonal models pertain to the simulation of cutting with three different CBN tool types. Chip formation, cutting forces and temperatures are compared for each model, at the same cutting conditions. Additionally, 3D models are presented, where the back rake angle of the cutting tool is varied. From the results it may be concluded that 3D models provide more realistic results but they are computationally more demanding than 2D models. Finite element modelling of high speed machining can provide data for the process that would be either difficult or in some cases even impossible to obtain through extensive experimental work.

PL

W artykule określono oddziaływanie geometrii narzędzia na wyniki symulacji numerycznej skrawania z dużą prędkością. Przeprowadzono symulację numeryczną dla skrawania ortogonalnego 2D, dla trzech modeli narzędzi z CBN o różnej geometrii. Porównano podział modeli numerycznych narzędzi na elementy skończone oraz przedstawiono analizę procesu kształtowania wióra, wartości składowych siły skrawania, temperaturę w strefie skrawania oraz odkształcenie plastyczne w warstwie wierzchniej dla wybranych ich geometrii. Przeprowadzono również proces symulacji dla modelu skośnego 3D dla różnych wartości kąta pochylenia krawędzi skrawającej. Wyniki symulacji pozwoliły stwierdzić, że zastosowanie modeli 3D lepiej odzwierciedla rzeczywisty proces. Stawia jednak większe wymagania w zakresie obliczeń niż przy użyciu modeli 2D. Symulacja MES obróbki z dużą prędkością pozwoliła uzyskać wyniki, które mogą być trudne lub w niektórych przypadkach niemożliwe do uzyskania w ramach badań eksperymentalnych.

7

Finite Element Modelling of burr formation in metal cutting

Pres P., Skoczyński W., Stembalski M.

Journal of Machine Engineering

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2014

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Vol. 14, No. 2

27--37

EN

The paper presents a two-dimensional FEM model of burr formation in metal cutting. Abaqus/Explicit software was used for the build of the model. The workpiece geometry, the tool and the cutting parameters were modelled. Physical properties and the method of deformation and fracture of the workpiece material is described using Johnson Cook's constitutive law and the ductile damage criterion. The simulation of the edge formation process during orthogonal cutting was carried out for different depths of cut and cutting speeds. The results of these simulations allowed the verification of the FEM model. The components of the resultant cutting force measured during the actual cutting process with the values of these forces determined based on FEM simulation of this process were compared. The geometry of burrs formed during the actual and simulated the edge forming process was assessed. The analysis showed that the FEM model built enabled a correct prediction of the shape of the workpiece edge and the estimation of geometric features of the edge.

8

Research and modeling workpiece edge formation process during orthogonal cutting

Preś P., Skoczyński W., Jaśkiewicz K.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 4

622--635

EN

This paper presented the study of the phenomenon of the material deformation at the edge of the workpiece during the orthogonal cutting of steel C45E and two-dimensional model of this process, developed with using the Finite Element Method. Based on the user's procedure VUMAT, the Johnson–Cook's law and Ductile Damage model were applied to describe the machined material. An extensive verification of the modeled process was performed. The phenomenon of material deformation at the edge of the workpiece during the actual orthogonal cutting process was recorded using a high speed camera. The courses of the real phenomenon with the modeled one were compared. The components of the resultant cutting force were measured during orthogonal cutting for different machining parameters. The measurement results were compared with the values of the components of the resultant cutting force calculated on the basis of numerical simulation. The studies on the burr formation mechanism were performed. The contactless measurement of selected geometric features of the burr was performed. The results of measurements of the selected geometric features of burrs obtained from the experiment were compared with those compiled based on FEM simulation.

9

Validation of Fe Modeling of Orthogonal Turning Process Using Cowper–Symonds Material Behavior Law

Gyliene V., Ostasevicius V.

Engineering Transactions

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2013

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Vol. 61, iss. 4

249–-263

EN

The article contains a literature review, experimental results, and a Finite Element Model (FEM) composition. Orthogonal turning tests were executed in the range of cutting speeds and feed rate, after every test chip was collected. Further investigation was done using FE model validation and experimentation, which uses results of the experimental zone in which the built-up edge did not form and the cutting itself is of even plastic deformation. The essence of this research is that the adequacy of the composed FE model to the real physical process should conform not only to the evaluation of cutting forces, but also to the evaluation of chip form, that is, segmentation frequency.

10

Numeryczne modelowanie rozpływu ciepła w strefie skrawania dla stali C45

Bartoszuk M.

Biuletyn Wojskowej Akademii Technicznej

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2013

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Vol. 62, nr 1

79-88

PL

Artykuł poświęcony jest zagadnieniu przepływu ciepła w czasie skrawania ortogonalnego stali C45 ostrzem węglikowym bez powłok ochronnych. W badaniach modelowych, do wyznaczenia zmian rozkładu temperatury oraz wartości średniej i maksymalnej temperatury kontaktu, zastosowano zmodyfikowaną metodę różnic skończonych. Badano zmiany dystrybucji temperatury w strefie skrawania wynikające z różnej konfiguracji kształtu strumienia ciepła generowanego na płaszczyźnie poślizgu oraz na długości kontaktu wiór-powierzchnia natarcia. Symulacje rozpływu ciepła prowadzono w oparciu o uproszczony model przepływu ciepła zakładający liniowe źródła ciepła o zmiennej intensywności wzdłuż całej swojej długości. Wyniki symulacji porównywano z danymi literaturowymi oraz wynikami eksperymentalnymi uzyskanymi na drodze pomiaru termoparą naturalną. Otrzymano akceptowalną dokładność średniej oraz maksymalnej temperatury kontaktu, potwierdzając tym samym poprawność modeli symulacyjnych.

EN

The paper concerns heat propagation while orthogonal cutting of C45 steel by means of the carbide cutting tool without protective coating. In the model tests, the modified finite difference method was applied for determination of changes of temperature distribution, the mean and maximum contact temperatures. The tests concerned changes of temperature distribution in the cutting zone, resulting from different shape configurations of the heat flux generated on the shear plane and at the contact length between the chip and the tool rake face. Simulations of heat propagation were based on the simplified model of the heat flow assuming linear heat sources of variable intensity along its whole length. The results of simulations were compared with the data from literature and experimental data obtained from measurements by means of natural thermocouple. Acceptable accuracy of the mean and maximum contact temperature was obtained, so correctness of the simulation models was proved.

11

Numeryczne modelowanie rozpływu ciepła w strefie kontaktu z wykorzystaniem metody różnic skończonych

Bartoszuk M.

Mechanik

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2012

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R. 85, nr 1CD

PL

Artykuł niniejszy omawia dystrybucję ciepła w czasie skrawania ortogonalnego stali 1H18N9T ostrzem węglikowym bez powłok ochronnych. W badaniach modelowych, do wyznaczenia zmian rozkładu temperatury oraz wartości średniej i maksymalnej tempe-ratury kontaktu, zastosowano zmodyfikowaną metodę różnic skończonych. Symulacje roz-pływu ciepła prowadzono w oparciu o uproszczony model przepływu ciepła zakładający liniowe źródła ciepła o zmiennej intensywności wzdłuż całej swojej długości. Wyniki sy-mulacji porównywano z danymi literaturowymi oraz wynikami eksperymentalnymi uzyska-nymi na drodze pomiaru termoparą naturalną. Otrzymano akceptowalną dokładność śred-niej oraz maksymalnej temperatury kontaktu wiór – powierzchnia natarcia, potwierdzając tym samym poprawność modeli symulacyjnych.

EN

This paper discusses the heat distribution during the orthogonal cutting of steel 1H18N9T using cemented carbide tool without protective coatings. In studies of model, to determine changes in temperature distribution and the average and maximum temperature of contact, used the modified method of finite differences. Simulations of heat propagation was based on a simplified model of heat flow assuming a linear heat source with variable intensity along its entire length. The simulation results were compared with literature data and experimental results obtained by measuring the natural thermocouple. A acceptable accuracy of the average and maximum temperature of tool-chip contact was obtained, thus correctness of simulation models was confirming.

12

Analysis of the cutting parameters influence during machining aluminium alloy A2024-T351 with uncoated carbide inserts

Haddag B., Atlati S., Nouari M., Barlier C., Zenasni M.

Engineering Transactions

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2012

|

Vol. 60, iss. 1

31-39

EN

This work aims to analyze the effect of the cutting parameters on chip segmentation of the aluminium alloy A2024-T351 during machining process. In this work, two parameters are considered: the tool rake angle of the cutting tool and the feed under dry machining. An orthogonal cutting FE model is developed in Abaqus/Explicit for this purpose. A thermo-visco- plastic-damage model for the machined material and thermo-rigid behaviour for the cutting tool have been assumed. At the chip/tool contact zone, the modified Coulomb friction model has been adopted. Thermal effects are considered by taking into account the heat flux generated by visco-plastic strain and also by friction at the tool-workpiece interface. The obtained results showed the effect of the tool rake angle and feed on the cutting force and chip morphology as well as temperature distribution at the tool rake face.

13

Microstructural characteristic of Ti-15V-3Al-3Sn-3Cr chips

Rokicki P., Nowag K., Spotz Z., Fusova L., Saksl K., Durisin J., Ghisleni R., Siemers C.

Rudy i Metale Nieżelazne

|

2010

|

R. 55, nr 7

452-456

EN

Titanium alloys like Ti-15V-3Al-3Sn-3Cr, a precipitation hardenable Beta-titanium alloy, are widely used in aerospace applications. Machining of Ti-15V-3Al-3Sn-3Cr, however, is difficult and expensive as its machinability is extremely poor. A thorough understanding of the chip formation process of Ti-15V-3Al-3Sn-3Cr is needed to improve related metal cutting operations. The aim of this article is to present the microstructure of Ti-15V-3Al-3Sn-3Cr chips prepared by turning. Chips from three states of the alloy were analyzed and compared: as-received, solution treated and aged. Chips were obtained in different speeds with different depths of cut. The microstructure was analyzed by means of optical, electron microscopy and hard XRD. During the experiments, depending of the cutting conditions, continuous or segmented chips were formed. Narrow highly deformed and grain oriented zone so-called "shear zone" separated individual segments. Different materials properties have been observed in shear zones and the segments. The results of the chips analyses have finally been used, to develop free-machining alloys based on Ti-15V-3Al-3Sn-3Cr.

PL

Stopy tytanu, takie jak Ti-15V-3Al-3Sn-3Cr, utwardzany wydzieleniowo stop o strukturze tytanu-Beta, są szeroko stosowane w przemyśle kosmicznym. Obróbka stopu Ti-15V-3Al-3Sn-3Cr jest jednakże trudna i kosztowna ze względu na trudnoobrabialność tych stopów. Kompleksowe zrozumienie procesu formowania wiórów Ti-15V-3Al-3Sn-3Cr jest konieczne do ulepszenia odpowiednich warunków obróbki. Celem tego artykułu jest prezentacja mikrostruktury wiórów stopu Ti-15V-3Al-3Sn-3Cr otrzymanych metodą toczenia. Wióry z trzech stanów obróbki termicznej zostały zanalizowane: stan wyjściowy, stan wyżarzony, stan starzony. Wióry zostały otrzymane z różnymi prędkościami cięcia i głębokościami penetracji narzędzia. Mikrostruktura została zanalizowana w zakresie mikroskopii optycznej, mikroskopii elektronowej i wysokoenergetycznego promieniowania rentgenowskiego. Podczas eksperymentów, w zależności od warunków obróbki, ciągłe lub segmentowane wióry zostały sformowane. Cienka, wysoce zdeformowana strefa zwana strefą płynięcia oddzieliła poszczególne segmenty. Różne własności materiałowe zostały zaobserwowane w strefach płynięcia i w segmentach. Rezultaty analizy wiórów zostały użyte do udoskonalenia, zmodyfikowania i otrzymania łatwo obrabialnych stopów na bazie Ti-15V-3Al-3Sn-3Cr.

14

Investigation on temperature distribution at the tool-chip interface under variable heat transfer conditions

Grzesik W., Bartoszuk M.

Advances in Manufacturing Science and Technology

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2008

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Vol. 32, nr 3

5-14

EN

This papers analyzes quantitatively heat transfer problem in the cutting tool in a steady-state orthogonal cutting when using uncoated carbide tools and the X5CrNi18-9 stainless steel as a work material. Finite Difference Approach (FDA) is applied to predict the changes of temperature distribution, and both average and maximum temperatures at the tool-chip interface, resulting from different the heat flux configuration. Moreover, some realistic computing errors due to possible measuring variations of the tool-chip contact length and the intensity of heat source were considered in simulations. Basically, uniformly distributed plane, symmetrical and asymmetrical triangular, and symmetrical and asymmetrical trapezoid-type heat flux configurations were accounted for. It was found that the assumption of an asymmetrical trapezoidal shape of heat flux configuration provides the simulated results closer to the experimental data.

PL

W artykule przedstawiono analizę transferu ciepła w narzędziach skrawających w przypadku skrawania ortogonalnego w warunkach procesu ustalonego, przy użyciu niepowlekanych ostrzy węglikowych i skrawaniu stali austenitycznej X5CrNi18-9. Do symulowania zmian rozpływu ciepła w strefie skrawania stosowano metodę różnic skończonych. Średnią oraz maksymalną temperaturę kontaktu wyznaczano dla różnych konfiguracji źródeł ciepła. W obliczeniach uwzględniano wpływ zmiany długości kontaktu oraz intensywność źródła ciepła. Uwzględniono podstawowe, płaskie źródło ciepła, Źródło trójkątne oraz trapezowe symetryczne i niesymetryczne. Udowodniono, że trapezowy asymetryczny kształt źródła ciepła pozwala uzyskać dobre przybliżenie wyników symulacji do danych eksperymentalnych.

15

Wyznaczanie naprężeń w ostrzu noża tokarskiego metodą elementów skończonych

Wodecki J.

Prace Naukowe Katedry Budowy Maszyn / Politechnika Śląska

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2006

|

nr 2

67-84

PL

Na podstawie badań modelowych, stosując metodę elementów skończonych, wyznaczono rozkłady naprężeń w ostrzu noża tokarskiego w warunkach skrawania ortogonalnego. Uwzględniono różne fazy obróbki; wcinanie ostrza w obrabiany materiał, ciągłe skrawanie oraz wyjścia ostrza z obrabianego materiału. Wskazano miejsca w ostrzu, w których naprężenia osiągają niebezpieczne wartości, decydujące o kruchej i plastycznej wytrzymałości narzędzia oraz zaproponowano hipotezy wytężeniowe, dla wyznaczenia niebezpiecznych wartości naprężeń redukowanych.

EN

On base of model investigations, using Finite Element Method, distributions of stresses in the wedge of cutting tool in conditions of orthogonal cutting were determined. Different kinds of machining were taken into consideration; sinking of the wedge into processed material, continuous cutting and exit from the material. The places in cutting tool were indicated, where the values of stresses achieve dangerous values, that decide about brittle and plastic strength of materials. Strength hypothesis for determination of dangerous values of reduced stresses were suggested.

16

Characterization of interfacial friction in orthogonal cutting when using heat isolating coatings.

Grzesik W., Niesłony P.

Advances in Manufacturing Science and Technology

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2003

|

Vol. 27, nr 2

5-16

EN

This paper provides a comprehensive knowledge on the frictional bahaviour exhibited during the cutting process resulting from the influence of so-called heat isolating coatings deposited on a WC-Co carbide substrate. For this purpose orthogonal end-turning tests with medium carbon and austenitic stainless steels when using tools treated with both multilayer coatings with intermediate Al2O3 ceramic layer and a monolayer (Ti,Al)N hard film, were performed. As a result, the fundamental frictional characteristics the friction force, the mean friction coefficient, the specific frictional energy and the corresponding thermal effects, the everage interface temperature and the frictional heat flux were determined. The mechanical, energy-based and thermal approaches to the frictional behaviour occurring in the carbide/ceramic coating-steel tribo-pairs were distinguished and quantified in terms of the process variables.

PL

W pracy omówiono możliwe rodzaje tarcia podczas skrawania ortogonalnego stali węglowej i austenitycznej ostrzami pokrywanymi twardymi warstwami o zwiększonej izolacji cieplnej. Badano ostrza z trój-- i czterowarstwowymi powłokami z przejściową warstwą ceramiczną oraz monowarstwą (Ti,Al)N. Dokonano analizy modyfikacji procesu tarcia na podstawie zmian pola i długości styku, siły i współczynnika tarcia, energii właściwej tarcia oraz temperatury kontaktowej i strumienia ciepła tarcia. Wykazano istotne zmiany mechanicznego, energetycznego i cieplnego charakteru warunków kontaktu w strefie styku substrat/powłoka-wiór prowadzące do zmniejszenia tarcia.