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EN
The paper presents an original technique for the numerical modeling of temperature dependent anisotropic viscoelastic properties in finite element codes. The study relates to the use of ANSYS Mechanical Student Products 17.2 code, but also is applicable to the other structural finite element codes. The solved one- and two-dimensional problems illustrate a possibility of an adaptation of the proposed combined-material model to the solution of model problems with a sufficient accuracy in comparison with the developed analytical solutions. An estimation of the performance of the technique shows its applicability to solution of the contact problems of orthotropic viscoelasticity of thin shells including multilayered options. The performed practical application of the method to the contact problem of cylindrical shell prove this point.
EN
Purpose: The paper presents the results of investigations on the changes in surface morphology, roughness, and thickness of the prepared aluminium oxide thin films as dependent on conditions of the thin films preparation. Design/methodology/approach: Thin films have been prepared with use of atomic layer deposition (ALD) method. The changes of surface morphology have been observed in topographic images performed with the atomic force microscope (AFM). Obtained roughness parameters have been calculated with XEI Park Systems software. The thickness distribution have been measured with spectroscopic ellipsometry. The optical transmission spectra have been measured with UV-Vis spectrophotometry. Findings: Results and their analysis show that the atomic layer deposition method allows the deposition of homogenous thin films of Al2O3 with the desired geometric characteristics and good optical properties. Practical implications: The technology of atomic layer deposition of aluminium oxide thin films causes that mentioned thin films are good potential material for optics, optoelectronics and photovoltaics. Originality/value: The paper presents results of investigations on aluminum oxide thin films prepared with atomic layer deposition method on glass substrate.
EN
Purpose: This study aims to investigate the potentiality of brush chromium plating process to replace conventional hard chromium plating. Design/methodology/approach: In this study brush chromium plating was applied over a H13 quality tool steel. Electron microscopy examinations and X-ray diffraction analysis were conducted in order to reveal the structural features of the coatings. Mechanical properties of the coatings were determined by hardness measurements and wear tests. Wear tests were conducted at room temperature and 500°C. Findings: Brush chromium plating, which is an environmental friendly alternative for conventional chromium plating, has potentiality to enhance wear resistance of steels. Research limitations/implications: Brush chromium plating process has good potential to replace hexavalent chromium. Further studies should focus on effect of electro-chemical parameters on structural properties of trivalent based hard chromium deposit by brush plating process. Originality/value: There have been significant researches on replacement of hexavalent based hard chromium plating in literature. Replacement by brush plating process with trivalent chromium containing electrolyte has been scarcely investigated especially for utilization in wear related applications at elevated temperatures.
4
Content available remote TEM microstructure investigations of aluminium alloys used as coating substrate
EN
Purpose: The aim of this paper was investigated structure and properties of gradient coatings produced in PVD process on AlSi9Cu aluminium alloys. Design/methodology/approach: The following results concern the structures of the substrates and coatings with the application of electron transmission and scanning microscopy; phase composition of the coatings using X-ray diffraction and grazing incident X-ray diffraction technique (GIXRD); microhardness and wear resistance. Findings: The deposited coatings are characterized by a single, double, or multi-layer structure according to the applied layers system, and the individual layers are coated even and tightly adhere to the substrate as well to each other. The analysis of coatings obtained on the surface of cast aluminium alloys by the PVD processes show a clear - over 100% - increase of the microhardness, compared to the base material microhardness. Practical implications: Achieving of new operational and functional characteristics and properties of commonly used materials, including the Al-Si-Cu alloys is often obtained by heat treatment, ie, precipitation hardening and/or surface treatment due to application or manufacturing of machined surface layer coatings of materials in a given group of materials used for different surface engineering processes. Originality/value: The paper presents the research involving the PVD coatings obtained on an unconventional substrate such as aluminium alloys. Contemporary materials should possess high mechanical properties, physical and chemical, as well as technological ones, to ensure long and reliable use. The above mentioned requirements and expectations regarding the contemporary materials are met by the non-ferrous metals alloys used nowadays, including the aluminium alloys.
EN
Purpose: The main aim of the this research was the investigation of the microstructure and the mechanical properties of the CrAlSiN+DLC coating deposited by hybrid PVD/PACVD process onto the X40CrMoV5-1 hot work tool steel substrate. Design/methodology/approach: The microstructure of the investigated coating was observed on the scanning electron microscopy and high resolution transmission electron microscopy. Tests of the coatings’ adhesion to the substrate material were made using the scratch test. A friction coefficient and the wear of coatings were determined in a test according to the ball-on-disk method. Findings: It was found that the microstructure of the nanocrystalline CrAlSiN layer consisted of fine crystallites, while their average size fitted within the range of 5-10 nm. The low-friction DLC show an amorphous character. The coating demonstrated a good adhesion to the substrate. The values of the critical load LC1 and LC2 of investigation coating account for, respectively, 36 and 76 N. In sliding dry friction conditions, after the break-in time, the friction coefficient for the investigated elements is set in the range between 0.03-0.05. The investigated coatings reveals high wear resistance. Practical implications: Economically efficient process improvement, increased production efficiency and quality and products reliability through increased durability and unfailing operation time of tools for plastic formation of non-ferrous metals and improved usable properties shall guarantee measurable economic effects to the manufacturers and users of the products. Moreover, it will enhance their competitiveness both on the domestic and overseas markets. Originality/value: The Author’s original approach was the development of a double-layer coating within one process. Such coating consists of the internal hard PVD layer providing the appropriate hardness, strength, low thermal conductivity and restricting the impact of external factors on the wear process and the external low-friction layer providing good tribological properties.
EN
Purpose: The article presents a concept of a hybrid layer, consisting of a gradient layer and anti-wear coat, intended for machine parts regeneration. Design/methodology/approach: The essence of method lies in the use of universal replacement material and its surface processing, which increases the hardness of the part that is being regenerated. The study was conducted on a material covered with a layer made of vacuum-nitraded padding weld of 17CrNi6-6, followed by an anti-wear DCL carbon coat. The morphology of thus created layers and their wear strength has been examined and their utility value has been evaluated. Findings: The hybrid layers under study have been found to improve the machine parts strength, while at the same time reducing frictional resistance, reducing the adhesion forces of the elements in contact and improving the corrosion resistance. Research limitations/implications: The method provides for making use of a versatile restoration material, which subsequently enables application of specific surface processing to improve the durability of the part being regenerated. Practical implications: It is a new concept of a hybrid layer, intended for machine parts regeneration.
PL
Struktura niniejszej rozprawy habilitacyjnej jest oparta na trzech częściach. Pierwsza z nich przedstawia przegląd dostępnej literatury dotyczącej właściwości tribologicznych powłok ditlenku tytanu. Druga część przedstawia najważniejsze osiągnięcia autora na polu badań tribologicznych cienkich powłok ditlenku tytanu otrzymywanych metodą zol-żel. Łącznikiem między nimi jest zwięzły opis przygotowania powłok, metod ich modyfikacji i zastosowanych technik eksperymentalnych. Przeprowadzony przegląd literatury pozwolił na wysunięcie wniosku, że właściwości tribologiczne ditlenku tytanu, materiału powszechnie stosowanego jako składnik nowoczesnych materiałów, nie zostały dostatecznie poznane. Pomimo rosnącej liczby publikacji dotyczących ditlenku tytanu stosunkowo mało z nich dotyczy ich właściwości tarciowych. Praca którą trzymacie Państwo w rękach wypełnia tę lukę. Jednocześnie praca ta stanowi wkład w pogłębienie wiedzy o właściwościach tribologicznych powłok ditlenku tytanu otrzymywanych metodą zol-żel. Celem pracy było zbadanie czynników wpływających na właściwości tribologiczne powłok ditlenku tytanu wytwarzanych na płytkach krzemowych z zastosowaniem metody zol-żel. Metoda ta pozwala na optymalizację i przygotowanie powłok ditlenku tytanu w powtarzalny sposób o ustalonych właściwościach. Należy podkreślić, że testy tarciowe prowadzono na mikrotribometrze - aparacie pracującym w zakresie obciążeń miliniutonów. Był on specjalnie zaprojektowany i zbudowany do badań tribologicznych cienkich powłok ceramicznych. Ten innowacyjny aparat powstał wg projektu dr. hab. Grzegorza Celichowskiego z Katedry Technologii i Chemii Materiałów Uniwersytetu Łódzkiego oraz został skonstruowany we współpracy z Instytutem Technologii Eksploatacji w Radomiu. Topografię oraz fizykochemiczne właściwości powłok były także charakteryzowane z zastosowaniem takich technik jak mikroskopia sił atomowych (AFM), spektroskopia w podczerwieni, mikroskopia optyczna i inne techniki. W części eksperymentalnej przedstawiono charakterystykę tribologiczną powłok ditlenku tytanu o grubości do 100 nm. Przedyskutowano wpływ temperatury wygrzewania powłok na ich strukturę i właściwości tribologiczne. Powłoki wygrzewano w 100°C, 500°C i 1000°C. W wyniku wygrzewania powstaje odpowiednio materiał amorficzny oraz tworzą się fazy anatazu i rutylu. Najniższy współczynnik tarcia technicznie suchego zarejestrowany dla styku tarciowego: powłoka zbudowana z rutylu - kulka cyrkonowa, wynosił około μ = 0,2. Jest to mniej niż w przypadku powłok wygrzewanych w temperaturze 100°C i 500°C. Powłoki wygrzewane w 1000°C wykazują również bardzo dobrą odporność na zużycie. Dobre właściwości tribologiczne powłok wygrzewanych w 500°C i 1000°C wynikają z powstawania twardych faz anatazu i rutylu oraz zwiększonej adhezji powłoki do podłoża. Następnie przebadano wpływ porowatości powłok na ich zużycie w testach tarciowych. Wykazano, że powłoki porowate wykazują znacznie mniejszą odporność na zużycie ścierne niż powłoki nieporowate. Powłoki porowate charakteryzują się także znaczną chropowatością powierzchni. Pomiary wykonane w skali nano i mikro wykazały, że wzrost chropowatości powierzchni pociąga za sobą wyższe wartości współczynnika tarcia. Badania zaprezentowane w tej pracy wykazały, że odporność na zużycie może być wzmocniona przez zastosowanie niejonowych środków powierzchniowo czynnych lub kopolimerów blokowych, zamiast środków powierzchniowo czynnych jonowych, w połączeniu z wygrzewaniem w wysokich temperaturach, tj. do 1000°C. W celu polepszenia właściwości tribologicznych powłok ditlenku tytanu wytwarzanych metodą zol-żel, zastosowano twardą fazę nanoceramiczną ZrO2. Powstałe kompozyty zbudowane z nanocząstek ditlenku cyrkonu w osnowie ditlenku tytanu wytwarzane były na płytkach krzemowych metodami przez zanurzanie i przez pokrywanie odśrodkowe oraz wygrzewane w 100°C, 500°C i 1000°C. Wykazano, że obecność nanocząstek ditlenku cyrkonu umiarkowanie obniża współczynnik tarcia tylko dla powłok wygrzewanych w 500°C w stosunku do powłok bez nanocząstek. W wyniku obecności nanocząstek obserwuje się natomiast znaczne zmniejszenie zużycia powłok. W szczególności powłoki wytworzone metodą przez pokrywanie odśrodkowe wykazywały wysoką odporność na zużycie. Obniżenie zużycia jest spowodowane wzrostem twardości powłoki oraz zmniejszeniem rzeczywistej powierzchni styku na szczytach nierówności, powodujące osłabienie oddziaływań adhezyjnych. Ostatnia część pracy poświęcona jest metodom obniżenia tarcia i zużycia poprzez modyfikację powierzchni. Po raz pierwszy zastosowano sole cynkowe dialkiloditiofosforanów (ZDTP) oraz wolne kwasy dialkiloditiofosforowe jako modyfikatory tarcia powłok ditlenku tytanu otrzymanych metodą zol-żel. Stosując te modyfikatory możliwe było obniżenie współczynnika tarcia z μ = 0,2 do μ = 0,05. Wartości te zarejestrowano odpowiednio dla powłoki ditlenku tytanu zbudowanej z rutylu i dla tej samej powłoki zmodyfikowanej kwasem di(tetradecylo-) ditiofosforowym nakładanym metodą przez zanurzanie. Analiza AFM topografii powierzchni po modyfikacji wykazała różne struktury cząsteczek ZDTP i HDTP na powierzchni w zależności od długości łańcucha alkilowego i metody nakładania. Topografie uzyskane techniką AFM wskazały również na występowanie warstw reakcyjnych kwasów HDTP na powierzchni powłoki ditlenku tytanu. Efekt ten nie jest obserwowany w przypadku cząsteczek ZDTP, które tworzą warstwy adsorpcyjne. Oprócz pochodnych dialkiloditiofosforowych badano również wpływ modyfikacji fluoroalkilosilanami na hydrofobowość powierzchni i swobodną energię powierzchniową. Pomiary wykonane w nanoskali z zastosowaniem AFM wykazały obniżenie tarcia na powłokach zmodyfikowanych fluoroalkilosilanami. Charakteryzowały się one także niższą, w stosunku do powłok niemodyfikowanych, swobodną energią powierzchniową. Nowym aspektem tej części pracy było zastosowanie dialkiloditiofosforanów mających w budowie cząsteczki łańcuchy poli(oksyetylenowe) oraz bezpośredniej polimeryzacji tlenku etylenu na powierzchni, jako modyfikatory tarcia powłok ditlenku tytanu. Ten rodzaj modyfikatorów stosowany jest w celu zwiększenia biozgodności implantów. Natomiast ich zachowanie jako modyfikatory tarcia na powłokach ditlenku tytanu opisano w tej pracy. Należy podkreślić, że większa część przytoczonych badań są to badania nowe i/lub rozszerzone. Nie były dotąd publikowane przez innych w literaturze.
EN
The structure of this work is based on three parts. The first part covers the review of the literature available today, related to the issues concerning the tribological properties of titanium dioxide coatings. The second part illustrates the most important achievements of the author in the field of the tribology of the thin titanium dioxide sol-gel coatings. The link between these two parts is a concise description of the coatings preparation, methods of their modification and applied experimental techniques. The review of the literature allowed to establish that tribological properties of titanium dioxide coatings, commonly used as a component of the modern materials, has not been fully characterized yet. In spite of the growing number of publications concerning the titanium dioxide, relatively small number of them concern its frictional properties. The work which you have in your hands fills in this gap. Simultaneously, this work constitutes a contribution in extending knowledge about the tribological properties of the thin titania sol-gel coatings. The aim of this work was investigation of the factors which influence the tribological properties of the titanium dioxide coatings deposited on silicon wafers using sol-gel method. This method enables optimization of the titanium dioxide coatings preparation, having easily achievable established properties, in the repeatable manner. It should be highlighted that frictional tests were conducted on the microtribometer - the apparatus operating in mN normal load range. It was especially designed and constructed for tribological investigation of the thin ceramic coatings. This innovative apparatus was designed according to the project presented by Prof. Grzegorz Celichowski from the Department of Materials Technology and Chemistry at the University of Lodz and constructed in cooperation with the Institute for Sustainable Technologies in Radom (Poland). The topography and physicochemical nature of coatings were also characterized by Atomic Force Microscopy (AFM), infra red spectroscopy (FT-IR), optical microscopy and other techniques. In experimental part the tribological characterization of the titanium dioxide coatings having thickness up to 100 nm was presented. The influence of the annealing temperature on the structure and the tribological properties was discussed. Coatings were annealed at 100°C, 500°C and 1000°C. As the result amorphous, anatase or rutile structures were obtained. The lowest coefficient of friction recorded on the microtribometer for these coatings, between rutile coating and zirconia ball, was on the level of μ = 0.2. It is low than in the case of coating annealed at 100°C and 500°C. Coatings annealed at 1000°C exhibited also very good wear resistance. Good tribological performance of the coatings annealed at 500°C and 1000°C is caused by the presence of hard crystalline phases (anatase, rutile) and enhanced adhesion to the substrate. Next, the effect of the porosity on the wear behavior in frictional tests was verified. It was found, that porous coatings exhibit very low wear performance than nonporous ones. Porous coatings exhibit also high roughness. Measurements performed in nano and micro scale revealed that the increase of the surface roughness causes higher coefficient of friction values. Investigations presented in this work demonstrate, that the wear resistance can be improved by application, on the preparation step, nonionic surfactants or block copolymers at low concentrations, instead of ionic surfactants combined with annealing at high temperatures up to 1000°C. In order to improve the tribological properties of titanium dioxide solgel coatings, hard zirconia nanoparticles were applied. Resulted composites, built of zirconia nanoparticles embedded in titanium dioxide matrix, were deposited on silicon wafers with the use of dip-coating or spin-coating methods and annealed at 100°C, 500°C and 1000°C. It was found that the presence of the zirconia nanoparticles moderately decreases the coefficient of friction. Slightly lower values of the coefficient of friction compared to pure titania coatings were recorded only for coatings annealed at 500°C. However, significant improvement in wear decrease was observed, due to the presence of hard zirconia nanophase. In particular, coatings deposited with the use of the spincoating method exhibited excellent wear performance. Reduction of the wear is caused by the increase of hardness of the coating and lowering of the real area of contact at the top of the asperities causing lower adhesive interactions.
EN
Purpose: The preliminary results of research on forming the aluminide coatings using CVD method were presented in the article. Design/methodology/approach: The coatings were obtained in low activity process on the surface of Rene 80 superalloy. The microstructure analysis and chemical composition analysis were performed applying different values of aluminizing process parameters. Findings: The authors present in the article the results of oxidation resistance analysis of aluminide coatings which were obtained on the surface of Rene 80 superalloy using various techniques. Research limitations/implications: The research results revealed the possibility of obtaining coatings by low activity aluminizing. Practical implications: This process can be used in aerospace industry to form oxidation resistant coatings. Originality/value: It was shown that the coating created during the CVD process was characterized by a good oxidation resistance at the temperature of 1100°C.
EN
Purpose: The aim of this paper is to investigate structure, mechanical and functional properties of sialon tool ceramics with wear resistant multicomponent coatings deposited with PVD method. Design/methodology/approach: The structural investigation includes the metallographic analysis on the scanning electron microscope. Examinations of the chemical compositions of the deposited coatings were carried out using the X-ray energy dispersive spectrograph EDS, and glow-discharge optical emission spectroscope GDOS. The investigation includes also analysis of the mechanical and functional properties of the material: microhardness tests of the deposited coatings, surface roughness tests, evaluation of the adhesion of the deposited coatings and tribological test made with the "pin-on-disk". Findings: Deposition of the multicomponent coatings with the PVD method, on tools made from sialon's ceramics, results in the increase of mechanical properties in comparison with uncoated tool materials, deciding thus the improvement of their working properties. Practical implications: The multicomponent coating carried out on multi point inserts (made on sintered sialon's ceramics) can be used in the pro-ecological dry cutting processes without using cutting fluids. However, application of this coating to cover sialon ceramics demands still both elaborating and improvement adhesion to substrates in order to introduce these to industrial applications. Originality/value: The paper presents some researches of multicomponent coatings deposited by PVD method on sialon tool ceramics.
EN
The stress-strain of thin multilayered coatings covered the surface of the rail is studied near the region of side contact in turning motion. The stress-strain state is studied for various geometric and mechanical coating parameters' values. A theoretical and a finite element models are developed. Stress-strain state analysis has been made based on models developed and recommendations were given for an optimal coating parameters' selection.
EN
Purpose: The main aim of this research was an investigation of both the coatings structure and mechanical properties deposited by the cathode arc evaporation physical vapor deposition (CAE-PVD) on sintered carbides and sialon tool ceramics substrates. Design/methodology/approach: The (Ti,Al)N and (Al,Ti)N coatings were investigated. Microstructure was characterized using the scanning and transmission electron microscopy. Phases composition analysis was carried out by the XRD and GIXRD method. Investigation of surface roughness was done. The mechanical properties were determined on basis of following research: a measurement of hardness using Vickres’s method, a measurement of roughness, adhesion using Scratch Test method. The cutting ability was defined on basis of technological cutting trials. Findings: The investigations made by use of the glow discharge optical emission spectrometer indicate the existence of the transition zone between the substrate material and the coating. The results shows that (Al,Ti)N coating presents good adhesion onto booth substrates and (Ti,Al)N coating presents good adhesion onto sintered carbides substrate. All the coatings demonstrate a high hardness. Research limitations/implications: The good adhesion (Al,Ti)N coating to sialon substrate is connecting with the same type of bonding in coat and sialon substrate. Originality/value: The good properties of the PVD gradient coatings make them suitable for various engineering and industrial applications.
EN
Purpose: The main aim of the this research was the investigation of the structure and the mechanical properties of the nanocomposite TiAlSiN, CrAlSiN, AlTiCrN coatings deposited by cathodic arc evaporation method onto hot work tool steel substrate. Design/methodology/approach: The surfaces’ topography and the structure of the PVD coatings were observed on the scanning electron microscopy. Diffraction and thin film structure were tested with the use of the transmission electron microscopy. The microhardness tests were made on the dynamic ultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test. Findings: It was found that the structure of the PVD coatings consisted of fine crystallites, while their average size fitted within the range of 11-25 nm, depending on the coating type. The coatings demonstrated columnar structure and dense cross-section morphology as well as good adhesion to the substrate. The critical load LC2 lies within the range of 46-54 N, depending on the coating and substrate type. The coatings demonstrate a high hardness (~40 GPa). Practical implications: In order to evaluate with more detail the possibility of applying these surface layers in tools, further investigations should be concentrated on the determination of the thermal fatigue resistance of the coatings. The very good mechanical properties of the nanocomposite coatings make them suitable in industrial applications. Originality/value: The investigation results will provide useful information to applying the nanocomposite coatings for the improvement of mechanical properties of the hot work tool steels.
13
Content available remote Comparison of the PVD coatings deposited onto plasma nitrited steel
EN
Purpose: The paper presents the structure, mechanical and tribological properties investigation results of the CrN, TiN and TiN/(Ti,Al)N anti-wear PVD coatings deposited onto substrates from the plasma nitrided hot work steel X37CrMoV5-1 type. Design/methodology/approach: Tests of the coatings’ adhesion to the substrate material were made using the scratch test. The surfaces’ topography and the structure of the PVD coatings were observed on the scanning electron microscopy. The microhardness tests were made on the dynamic ultra-microhardness tester. Wear resistance tests with the pin-on-disc method were carried out on the CSEM THT (High Temperature Tribometer). Findings: The duplex coatings demonstrate high hardness and very good adhesion. It was found out that the duplex TiN/(Ti,Al)N coating show the best adhesion to the substrate material. Practical implications: This investigation is to determine the usefulness of CrN and TiN, TiN/(Ti,Al)N PVD coatings deposition in order to improve the mechanical and tribological properties of hot work steels, particularly X37CrMoV5-1 type one. Originality/value: The investigation results will provide useful information to applying the duplex and nanostructure PVD coatings for the improvement of mechanical properties of the hot work tool steels. The very hard and antiwear PVD coatings deposited onto hot work tool steel substrate are needed.
EN
Purpose: The aim of the paper was the investigation of the structure and the mechanical properties of the duplex TiN/(Ti,Al)N coating and the nanostructure TiAlN coating deposited by PVD technology onto hot work tool steel substrate. Design/methodology/approach: The surfaces’ topography and the structure of the PVD coatings were observed on the scanning electron microscopy. Diffraction and thin film structure were tested with the use of the transmission electron microscopy. The microhardness tests were made on the dynamic ultra-microhardness tester. Tests of the coatings’ adhesion to the substrate material were made using the scratch test. Findings: The duplex and nanostructure coatings demonstrate high hardness and very good adhesion. The critical load LC2 (coating delamination) lies within the range 80-85 N, depending on the coating type. It was found out that the duplex TiN/(Ti,Al)N coating show the best adhesion to the substrate material. Practical implications: The very good mechanical properties of the duplex and nanostructure PVD coatings make them suitable in industrial applications. Originality/value: The investigation results will provide useful information to applying the duplex and nanostructure PVD coatings for the improvement of mechanical properties of the hot work tool steels. The very hard and antiwear PVD coatings deposited onto hot work tool steel substrates are needed.
15
Content available remote Technology validation of coatings deposition onto the brass substrate
EN
manufacturing metallic-ceramic coatings in the process of physical vapor deposition (PVD) on the CuZn40Pb2 brass substrate. The amount of layers applied to the substrate was adopted as the criterion for technology division, thus obtaining three technology groups for foresight researches. Design/methodology/approach: The carried out foresight-materials science researches included creating a dendrological matrix of technology value, a meteorological matrix of environment influence, a matrix of strategies for technologies, laying out strategic development tracks, carrying out materials science experiments which test the mechanical and tribological properties and the resistance to corrosion and erosion of brass covered with a varied number of layers applied using the method of reactive magnetron evaporation, as well as preparing technology roadmaps. Findings: High potential and attractiveness were shown of the analyzed technologies against the environment, as well as a promising improvement of mechanical and tribological properties and an increase of resistance to material corrosion and erosion as a result of covering with PVD coatings. Research limitations/implications: Researches pertaining to covering the brass substrate with PVD coatings is part of a bigger research project aimed at selecting, researching and characterizing priority innovative material surface engineering technologies. Practical implications: The presented results of experimental materials science researches prove the significant positive impact of covering with PVD coatings on the structure and mechanical properties, as well as the resistance to corrosion, erosion and abrasive wear of brass which leads to the justification of their including into the set of priority innovative technologies recommended for application in industrial practice, including in small and medium-size companies. Originality/value: The advantage of the article is the specification of the significance of the technology involving covering the brass substrate with mono- and multilayer PVD coatings against the environment, together with the recommended strategies of conduct, strategic development tracks and roadmaps of these technologies, taking into account the impact of the processes of applying these coatings onto the structure and the improvement of the properties of the tested surface layers.
16
Content available remote Investigation of PVD coatings deposited on the Si3N4 and sialon tool ceramics
EN
Purpose: The paper presents investigation results of the structure and properties of the coatings deposited by cathodic arc evaporation - physical vapour deposition (CAE-PVD) techniques on the Si3N4 and sialon tool ceramics. The Ti(B,N), Ti(C,N), (Ti,Zr)N and (Ti,Al)N coatings were investigated. Design/methodology/approach: The structural investigation includes the metallographic analysis on the scanning electron microscope. Examinations of the chemical compositions of the deposited coatings were carried out using the X-ray energy dispersive spectrograph EDS and using the X-ray diffractometer. The investigation includes also analysis of the mechanical and functional properties of the material: microhardness tests of the deposited coatings, surface roughness tests, evaluation of the adhesion of the deposited coatings. Findings: Deposition of the multicomponent gradient coatings with the PVD method, based on the B, Al and Zr solid secondary solution in the TiN titanium nitride, isomorphous with the alternating pure titanium nitride TiN, on tools made from nitride ceramics and sialon's ceramics, results in the increase of mechanical properties in comparison with uncoated tool materials, deciding thus the improvement of their working properties. Research limitations/implications: Ti(B,N), Ti(C,N), (Ti,Zr)N and (Ti,Al)N multicomponent and gradient coatings can be applied for cutting ceramic tools. Originality/value: Comparison of the wide
17
Content available remote Metallographic preparation of the conventional and new TBC layers
EN
Purpose: Verification of up-to-now used metallographic preparation of the TBC coating thermal barriers and adaptation of them to layers of new types, based on new ceramic compounds, sprayed on conventional high temperature creep resisting alloys by the APS method, is a purpose of this paper. New types of used ceramic powders are so called pyrochlores of a general formula RE₂Zr₂O₇. Design/methodology/approach: A scope of investigations comprised realization of a process of preparation of metallographic micro-sections, beginning from a cutting moment, through mounting, grinding and polishing. A standard method of preparation of micro-sections, typical for conventional layers was used and microstructural observation, from a point of view of presence of artefacts of mechanical origin was carried out. Findings: The carried out analysis allowed to compare methods of preparation of micro-sections and principles of preparation, used to assess the conventional TBC layers and relation them to barrier layers of new types. The carried out investigations showed that up-to-now used methods and procedures for the TBC layers, got by usage of conventional powders, are sufficient for layers of new types. Research limitations/implications: The carried out investigations suggest a necessity to verify the got results in a case of the TBC layers, sprayed by use of powders of pyrochlore structure of another type. Practical implications: The got results show a possibility to use up-to-now metallographic procedures for the TBC layers of new types. Originality/value: Information, concerning basic principles of microstructural assessment of layers of new types, sprayed by the APS method on high temperature creep resisting alloys, is an original value.
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Content available remote Metodyka badania właściwości tribologicznych powłok nanoszonych techniką PVD.
PL
W wyniku przeprowadzonej analizy dostępnej literatury stwierdzono, że na wyniki badań tribologicznych cienkich, twardych powłok nanoszonych techniką PVD mają znaczący wpływ następujące czynniki: - podłoże (twardość, chropowatość), - grubość powłoki, - rodzaj ruchu (poślizg lub toczenie), - warunki testu (rodzaj materiału przeciwpróbki, wilgotność powietrza otaczającego, prędkość poślizgu, obciążenie, temperatura otoczenia, poziom drgań węzła tarcia). Praktycznie oznacza to, że można ze sobą porównywać tylko te wyniki, które uzyskane zostały w takich samych, bądź zbliżonych warunkach. W związku z tym opracowano metodykę badań tribologicznych cienkich, twardych powłok nanoszonych techniką PVD, ściśle definiując praktycznie wszystkie omawiane czynniki. Wybrano skojarzenie kula-tarcza pracujące w warunkach tarcia technicznie suchego. Badana powłoka TiN naniesiona została na stalową tarczę (stal WCL, twardość 50 HRC) i miała grubość 2 mikrometry. Do obracającej się w płaszczyźnie poziomej tarczy dociskana jest przeciwpróbka, czyli kulka wykonana z Al2O3. Parametry badań przyjęto w oparciu o normy ASTM G 99-90, DIN 50324 oraz założenia programu VAMAS TWA1. W badaniach wykorzystano urządzenie do precyzyjnego testowania cienkich powłok, oznaczone T-10. Zostało ono opracowane i jest wytwarzane w ITeE w Radomiu. Wykorzystując opracowaną metodykę zbadano także inne powłoki nanoszone techniką PVD, tj. CrN oraz Ti(C,N). Stwierdzono, że najlepszymi waściwościami przeciwzużyciowymi charakteryzuje się powłoka CrN, zaś najgorszymi - Ti(C,N). Prace wykonano w ramach projektu pt. "Badania porównawcze tribologicznych własności powłok przeciwzużyciowych" - program COST Akcja 516 Tribology.
EN
As a result of an overview of the literature, it is apparent that all of the below factors have a significant effect on the friction coefficient and/or wear obtained for thin hard coatings deposited by the PVD process: - substrate (hardness, roughness), - coating thickness, - kind of motion (sliding or rolling), - test conditions (counterbody material, air relative humidity, sliding speed, load, ambient temperature, friction pair vibrations). This practically means that only results obtained under identical or close test conditions are comparable. Taking the above conclusions into consideration, the authors have elaborated a method for tribological testing of thin hard coatings deposited by the PVD process. They have precisely defined almost all the mentioned factors. The authors chose the unlubricated ball-on-disk tribosystem. The investigated 2 micrometers thick TiN coating was deposited on the steel disk (WCL steel, hardness HRC 50). The counterbody, i.e. Al2O3 ball was pressed against the disc rotating in the horizontal plane. The test conditions generally conformed to the ASTM G 99-90 and DIN 50324 standards as well as VAMAS TWA1 project. The experiments were conducted using a ball-on-disc tribotester, known as T-10, intended for precise investigation of thin hard coatings. The T-10 tester has been designed and is manufactured at ITeE in Radom. The authors employed the developed method to investigate other PVD coatings, i.e. CrN and Ti(C,N). It was shown that CrN coatings exhibit much better antiwear properties than TiN, and Ti(C,N) - worse. This work has been carried out within the framework of the project: 'Comparison of tribological properties of ceramic coatings including studies of the repeatability of tests' - COST Action 516 Tribology.
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