Symposium : U
|Carbon- or nitrogen-containing nanostructured films I : A. Cavaleiro, C. Mitterer|
|09:00||Phase formation of transition metal aluminum carbide nanolaminates|
Authors : Jochen M. Schneider
Affiliations : Materials Chemistry, RWTH Aachen University
Resume : Magnetron sputtering has been employed to grow Cr2AlC and V2AlC nanolaminate thin films. The effect of the substrate temperature on the phase formation has been investigated. Amorphous thin films were grown at room temperature and removed from the substrate to study the crystallization kinetics by differential scanning calorimetry (DSC) and X-ray diffraction. These data were compared to critical temperatures observed during vapor phase condensation of crystalline thin films. Significant differences with respect to the phase formation temperatures are observed for Cr2AlC. These data support the conclusion that surface diffusion is an important mechanism during structure evolution of Cr2AlC phase thin films grown at low substrate temperatures. For V2AlC the role of surface diffusion is unclear at this point as no vapor phase condensation experiments are reported to date that can exclude bulk diffusion from being the dominant mechanism for structure evolution.
|09:30||Growth and characterization of TiAlN/AlN superlattices prepared by reactive magnetron sputtering|
Authors : A. Rizzo1, A. Cappello1, U. Gallietti2, M. Massaro1, L.Tapfer1, D. Valerini1
Affiliations : (1) ENEA - Italian National Agency for New Technologies, Energy and the Sustainable Economic Development, Technical Unit for Materials Technologies – Brindisi Research Center, S.S. 7 Appia km. 706, 72100 Brindisi, Italy (2) Politecnico di Bari, DIMEG - Dipartimento di Ingegneria Meccanica e Gestionale, Viale Japigia 182, I-70126 Bari, Italy
Resume : Machining of aerospace materials is one of the major challenges of modern manufacturing. Application of nano-multi layered AlTiN/AlN PVD coatings to cemented carbide tooling results in a signiﬁcant tool life improvement under conditions of cutting hard to machine alloys such as Ni-based Incone l 718 superalloy and Ti-based TiAl6V4 alloy . TiAlN and AlN coatings were prepared using a reactive magnetron sputtering system from TiAl and Al targets. Structural characterization of the coatings using x-ray diffraction (XRD) revealed the B1 NaCl structure of TiAlN with a prominent reflection along the (111) plane and hexagonal wurtizite phase of AlN coatings. Subsequently, nanolayered multilayer coatings of TiAlN/AlN were deposited on silicon and WC-Co substrates at different modulation wavelengths (Λ) with a total thickness of approximately 1.0m. The modulation wavelengths were calculated from the x-ray reflectivity data using modified Bragg’s law. TiAlN/AlN multilayer coatings were textured along (111) for Λ<200 ? Study of thermal stability of the coatings in air indicated that the TiAlN/AlN multilayer coatings were stable up to 900°C in air. TiAlN/AlN multilayer coatings also exhibited improved wear resistance when compared to the substrate.
|10:30||Phase stability tuning through phase shifted synchronized ion bombardment during Ti-Al-N thin film growth by HPPMS|
Authors : Jens Emmerlich, Stanislav Mráz, Jie Zhang, Jochen M. Schneider
Affiliations : Materials Chemistry, RWTH Aachen University, Germany
Resume : During high power pulsed magnetron sputtering (HPPMS/HiPIMS) the high discharge power, typically in kW/cm²-range, is dissipated during short pulses (25 µs to 200 µs). This results in very high ionization rates of the discharge gas in the beginning of the pulse, while later, gas rarefaction takes place enabling significant ionization of the film-forming species [Macak et al. J. Vac. Sci. Technol. A 18, 1533 (2000)]. Depending on the discharge conditions, peak substrate current densities on the order of 1 A/cm² are reported and, hence, transients in plasma parameters are generated, affecting the structure evolution in a complex way. Here, we apply a substrate bias potential, which is synchronized with the discharge pulse. By tuning the shape of the bias pulse and the phase shift with respect to the discharge pulse the ion current through the substrate as well as the ion energy flux can be well controlled without influencing the plasma conditions. Additionally, it can be controlled whether discharge-gas ions or ions of the film-forming species should predominantly govern the film growth. Using XRD, EDX as well as nanoindentation we show that phase formation and mechanical properties of Ti-Al-N films can be influenced.
|10:50||Wavelength modulation of TiAlN / Ti-Al-V-N multilayers by various substrate rotation speeds|
Authors : M. Pfeiler, P.H. Mayrhofer, K. Chladil, M. Penoy, C. Michotte, C. Mitterer, M. Kathrein
Affiliations : Materials Center Leoben Forschung GmbH, Roseggerstraße 12, A-8700 Leoben, Austria Department of Physical Metallurgy and Materials Testing, Montanuniversität Leoben, Franz-Josef-Straße 18, A-8700 Leoben, Austria Ceratizit Luxembourg S.à.r.l., Mamer, Luxembourg Ceratizit Austria G.m.b.H., A-6600 Reutte, Austria
Resume : TiAlN / Ti-Al-V-N multilayered coatings were grown on cemented carbide and silicon (100) substrates by cathodic arc evaporation. The wavelength of the multilayer was modified by varying the rotation speed of the substrate carousel during deposition. The use of a fcc TiAlN template enables the epitaxial fcc stabilization of the originally dual phase fcc+hcp Ti-Al-V-N structure. The stabilization effect can be realised up to high multilayer wavelengths exceeding 40 nm. This leads to improved hardness and Young´s modulus due to hindered formation of hcp phases, without the necessity of high bias voltages. The mechanical properties were found to be independent of the substrate rotation speed. Wear at room temperature was found unaffected by the varied multilayer wavelength. The wear at 500°C was improved with increasing rotation speed, which is connected with a higher amount of TiAlN layers acting as diffusion barrier for the harmful V out-diffusion. This barrier function is also found at 700°C, although at a reduced scale and independent from the multilayer wavelength. The results show that the application of a fcc template layer leads to a significant improvement of the properties of Ti-Al-V-N coatings, without necessarily applying high bias voltages and thus creating high compressive stresses.
|11:10||Influence of Al content on the mechanical properties and thermal stability in protective and oxidation atmospheres of Zr-Cr-Al-N coatings|
Authors : W.Z. Li 1, 2, M. Evaristo 1, T. Polcar 3, A. Cavaleiro 1
Affiliations : 1) SEG-CEMUC - Department of Mechanical Engineering, University of Coimbra, Rua Luís Reis Santos, P-3030 788 Coimbra, Portugal ; 2) School of Materials Science and Engineering, Guangxi University, Nanning 530004, PR China; 3) National Centre for Advanced Tribology at Southampton (nCATS), School of Engineering Sciences, University of Southampton, Highfield, Southampton, SO17 1BJ, Hampshire, UK
Resume : Tools have been used under very high temperature in recent decades. Therefore, the coatings on the tools are required to be thermally stable and excellent in oxidation-resistance. The introduction of Al into nitride coatings was considered as an effective way to improve the coating oxidation-resistance and thermal stability. Till now, research of effect of Al on the high temperature mechanical properties and oxidation-resistance of Zr-Cr-N coatings has not been reported yet. Quaternary Zr-Cr-Al-N coatings were deposited with increasing Al contents by d.c. reactive magnetron sputtering. The coatings were annealed at 700, 800 and 900oC in Ar + H2 atmosphere and exposed at 1200oC for 1h in air, respectively. The hardness, Young’s modulus, adhesive/cohesive strength and residual stress of as-deposited and annealed coatings were characterized by nanoindentation, scratch test and curvature measurement method. The results showed that the coating hardness and adhesive/cohesive strength almost did not change during annealing at 700 and 800oC, and clearly decreased at 900oC due to surface oxidization. The residual stress increased with annealing temperature in high Al coatings which showed a lower crystallinity degree. XRD patterns for the oxidized samples showed a mixture of oxides based on Cr2O3 with the presence of ZrO2 in the Al-free or low Al coating, and Al2O3 in the high Al coating. This oxide seems to be in the basis of the low onset oxidation temperature of the coatings.
|11:30||Compositional, structural and mechanical evolution of sputtered Zr-Al-N thin films|
Authors : Luef Doris, Joerg Paulitsch, Paul H. Mayrhofer
Affiliations : Department of Physical Metallurgy and Materials Testing, Montanuniversitaet Leoben, Franz-Josef-Str. 18, A-8700 Leoben, Austria
Resume : The compositional and structural evolution of ZrAlN thin films as a function of the N2-to-total pressure ratio (pN2/pT) and the substrate position during reactive sputtering of powder-metallurgically prepared Zr0.7Al0.3 and Zr0.6Al0.4 targets are investigated in detail. Based on these studies we can conclude that the Al incorporation to the prepared films as well as their crystalline structure is highly dominated by the N2 partial pressure used. Face-centered-cubic (fcc) coatings are obtained when using low pN2/pT ratios of ~10%, whereas higher ratios lead to the formation of a nanocrystalline material composed of multiple phases. The fcc coatings also exhibit the highest hardness values of ~30 GPa. Comparative studies are conducted with non-reactively sputtered ZrAlN thin films using a powder metallurgically prepared (ZrN)0.6-(AlN)0.4 target. These coatings exhibit the highest crystallinity with fcc structure among the coatings investigated combined with a hardness of ~30 GPa. The structural evolution of the ZrAlN coatings prepared by non-reactive sputtering and by reactive sputtering with pN2/pT ~10% is followed as a function of annealing in vacuum and N2-atmosphere up to temperatures of 1100 °C. These annealing treatments are guided by dynamical differential scanning calorimetric studies. The ZrAlN coatings exhibit only small changes in crystal structure upon annealing to 800 °C and hence also their hardness is close to the as deposited value of ~30 GPa.
|11:50||Combined XRD and XAFS study of the crystalline structure of V-C-Al-N|
Authors : S. Darma (1) , B. Krause (1), S. Mangold (1), S. Doyle (1), S. Ulrich (2), M. Stüber (2), T. Baumbach (1)
Affiliations : (1) ISS, Karlsruher Institut für Technologie (2) IAM-AWP, Karlsruher Institut für Technologie
Resume : Multi-element hard coatings e.g. in the material system V-Al-C-N are of great interest for many technological applications. Their mechanical properties depend on the composition, crystalline phase and microstructure of the coating. Here we will present the results of a combined X-ray diffraction (XRD) and X-ray absorption fine structure spectroscopy (XAFS) study of the composition-dependent crystalline phase of V-C-Al-N. The films were deposited by reactive RF magnetron sputtering from a segmented target composed of AlN and VC. Synchrotron radiation measurements where performed at the beamlines PDIFF and XAS at the Angstromquelle Karlsruhe (ANKA). The experimental results are consistent with the theoretically predicted metastable fcc (V,Al)(C,N) phase.
|Carbon- or nitrogen-containing nanostructured films II : M. Braic, J.M. Schneider|
|14:00||Nanostructured thin film coatings for surface modification of wood machining tools|
Authors : Witold Gulbiński
Affiliations : Koszalin University of Technology Institute of Mechatronics, Nanotechnology and Vacuum Technique
Resume : Working condition of tools during wood machining differ substantially from those typical for cutting, drilling or turning of metals. Cutting edge is exposed to high temperature due to low thermal conductivity of processed material. Anisotropy of wood structure accompanied by its local inhomogenities is a reason for abrupt changes of tool load. Natural moisture of machined material together with corrosive substances released during this process promote corrosive wear and tool blunting. Even though a high variety of materials, including low alloy steels, high speed steels, stellites, cemented carbides or synthetic diamond based composites has been developed, further improvement of tool performance is needed. Recently, an important progress has been achieved by using advanced tool surface engineering technologies, including hard, wear resistant coatings based on nitrides and carbides of transition metals, diamond-like materials and composites. The state of the art description of the most often used materials and structures is presented. A particular attention is paid to multi-component and multiphase nano-composite based coatings including nitrides, carbides and amorphous carbon. Their structures and properties directly related to tool life and performance are presented and discussed.
|14:30||Low friction CrN/TiN coatings; a theoretical approach|
Authors : Joerg Paulitsch, David Holec, Paul H. Mayrhofer
Affiliations : Department of Physical Metallurgy and Materials Testing Montanuniversität Leoben
Resume : Deposition processes like the high power impulse magnetron sputtering (HIPIMS) or the modulated pulse power (MPP) technique indicate high metal ion ratios in the plasma, which can be used to further control the structural development of the coatings prepared. Recently we showed that a multilayer architecture of CrN and TiN, deposited using a combination of high ionizing sputtering techniques with conventional DCMS (direct current magnetron sputtering), results in coatings exhibiting friction coefficients below 0.1, when tested at RT and ambient air conditions, wear rates in the range of 2•10-16 Nm/m³ and hardness values around 25 GPa. Furthermore, investigations during dry sliding indicated that by decreasing the relative humidity during testing by introducing argon, nitrogen or synthetic air, the coefficient of friction increases to values around 0.7, whereas measurements in water also results in values below 0.1. First principal studies of our multi-layered CrN/TiN coatings using density function theory were carried out to achieve information on the binding energies of hydrogen and oxygen atoms on either CrN or TiN (001) surfaces. These simulations support our hypothesis of possible water formation on the free standing surfaces of CrN and TiN within the wear track explaining the low coefficient of friction due to a bearing-like behaviour of water drops.
|14:50||Wear behavior of TiN/Cu superlattice coatings|
Authors : Ozcan BIRSOZ, Dursun EKREN, Mustafa URGEN, Kursat KAZMANLI
Affiliations : Istanbul Technical University, Dept. of Metallurgical and Materials Eng., Istanbul /Turkey
Resume : In the literature, superlattice coatings have been studied by various investigators. Although, the hardness increase depending on the each layer properties and the super lattice periods was well reported, the wear properties of super lattice coatings have not been investigated. On the other hand, in the last decade, the reports on nano composite coatings showed that the secondary components in nano composite coatings (ie. Cu in nc-Mo-N-Cu and nc-Ti-N-Cu) improved the wear and friction behavior of the coatings along with the hardness. The similar improvements in wear and friction behavior can also be expected for superlattice coatings. In this study wear behavior of TiN/Cu superlattice coatings was investigated. The TiN and Cu layers were deposited by cathodic arc and magnetron sputtering PVD techniques, respectively. A shutter between the copper magnetron target and the titanium arc cathode was used to separate the Cu and Ti plasmas. Substrate rotation speed, bias potential applied to the samples and evaporation currents were changed in order to alter the thickness of the layers and the super lattice periods. The samples were characterized by X-ray diffraction and scanning electron microscopy. The super lattice periods were determined by using X-ray reflection and scanning electron microscopy investigations. Super lattice periods and the coating hardness measured by depth sensing indentation technique were compared. Wear behavior of the coatings was tested and the wear track and debris were analyzed using Raman spectroscopy technique.
|15:10||Tribological behaviors of CrAlSixN coatings derived from RF magnetron sputtering|
Authors : Hsien-Wei Chen, Chih-Hsiung Lin, Yu-Chen Chan, Jenq-Gong Duh, Jyh-Wei Lee
Affiliations : Department of Material Science and Engineering, National Tsing-Hua University, Hsinchu, Taiwan
Resume : The CrAlSiN coatings with Si contents from 0 at.% to 13.0 at.% were deposited on AISI 304 stainless steels by magnetron sputtering. In the pin-on-disc wear tests, the improved friction coefficients of CrAlSiN coatings were revealed. The hardness and the H3/E*2 ratio of CrAlSixN coatings were acquired by a nanoindentation. The CrAlSiN coating with 9.0 at.% Si exhibited an H3/E*2 ratio as high as 0.475, implying its superior resistance to plastic deformation. In addition, it was revealed that the columnar grains of the CrAlN coatings were switched to refined and equi-axial ones after Si addition. From the observation of crack propagation, it was evidenced that the sophisticated grain boundary of CrAlSiN coating prevented the direct penetration of the cracks as well as large debris. On the basis of these improved tribological behaviors, the superior durability of CrAlSiN coating was thus demonstrated.
|Carbon- or nitrogen-containing nanostructured films III : M. Stüber, L. Zajickova|
|16:10||Thermal stability of titanium nitride films|
Authors : Sunil Bhardwaj, Carla Castellarin Cudia, Cinzia Cepek
Affiliations : Istituto Officina dei Materiali – CNR, National Laboratory TASC, Trieste, Italy
Resume : The nitrides of titanium are becoming more important for their applications in protective coatings. But the basic properties like electrical conductivity and metallic reflectivity of these films depends on its synthesis methods, Titanium nitride films are commonly prepared by sublimation and reaction of pure titanium with nitrogen in sputter deposition, cathodic arc deposition, electron beam heating and chemical vapor deposition. In this paper we have studied the thermal stability of TiN films up to 600oC in UHV conditions. Films are prepared by two different methods; atomic layer deposition and sputter deposition. In – situ XPS studies are made to analyse the chemical changes occurring during the annealing. Physical morphologies were analysed by SEM. It seems that the chemical composition and stoichiometry of these two films are very different. TiN films obtained by ALD are quite stable and gets cleaned (from adsorbed atmospheric contaminants) very easily on annealing in UHV condition. While the films deposited by sputter deposition are not so stable and reacts with atmospheric contaminants. At high temperature they start forming cracks and its morphology is disturbed.
|16:30||Comparison of Mo-N-Cu nanocomposite coatings produced by magnetron sputtering and cathodic arc evaporation techniques|
Authors : M. Mohammadimoghanjoughi, O.Levent Eryilmaz, Ali Erdemir, Kursat Kazmanli, Mustafa Urgen
Affiliations : M. Mohammadimoghanjoughi,ITU; O.Levent Eryilmaz,ANL; Ali Erdemir, ANL; Kursat Kazmanli,ITU; Mustafa Urgen, ITU
Resume : Comparison of Mo-N-Cu Nano Composite Coatings Produced by Magnetron Sputtering and Cathodic Arc Evaporation Techniques M. Mohammadimoghanjoughi1, O.Levent Eryilmaz2, Ali Erdemir2, Kursat Kazmanli1, Mustafa Urgen1 1 Istanbul Technical University, Dept. of Metallurgical and Materials Eng., Istanbul /Turkey 2Argonne National Laboratory, Argonne – IL / USA Abstract In the last decade, the nano composite hard coatings have been gained increasing attraction by investigators because of the superior properties comparing to the conventional coatings. The high hardness and good wear behavior of nano composite coatings have been promising a good application potential. The properties and the performance of the nano composite coatings depend on content of the secondary metallic component. In production of nano composite coatings composing of immiscible components with different melting points, there are some difficulties in having homogenous compositions. On the other hand, fine adjustment of the composition in nano composite coatings, especially in low concentrations, is another challenge. In order to overcome these difficulties, alloy target and cathodes are mostly chosen. It is also well known that the deposition techniques used have a strong effect on the structure and properties of coatings. In this study Mo-N-Cu nano composite coatings produced by magnetron sputtering and cathodic arc evaporation techniques using Mo-Cu alloy targets and cathodes. Their structural and mechanical
|16:50||Very hard nanostructured ZrC and TiN films grown by pulsed laser deposition|
Authors : D. Craciun1, S. Niculaie1, G. Socol1, G. Dorcioman1, E. McCumiskey2, M. Hanna2, C. R. Taylor2, G. Bourne3, E. Lambers4, and V. Craciun1, 4
Affiliations : 1Laser Department, National Institute for Laser, Plasma, and Radiation Physics, Bucharest, Romania 2Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611, USA 3Metallurgical and Materials Engineering, Colorado School of Mines, Golden, CO 80401, USA 4Major Analytical Instrumentation Center, College of Engineering, University of Florida, Gainesville, FL 32611, USA
Resume : ZrC and TiN films thinner than 300 nm were grown on (100) Si substrates from room temperature up to 500 oC by the pulsed laser deposition (PLD) technique using a KrF excimer laser (=248 nm, pulse duration τ = 25 ns, 6.0-10 J/cm2 fluence and 40 Hz repetition rate) under various atmospheres. Simulation of X-ray reflectivity curves acquired from films showed they were very dense and smooth, while X-ray diffraction investigations found they were nanocrystalline, with crystallites size from 10 to 30 nm and micro-strain values of 0.5 % to 1.2 %. Nanoindentation investigations found hardness values between 35 and 40 GPa, amongst the highest values reported for ZrC or TiN films. The high laser fluence used for ablation generated energetic ions and atomic species that bombarded the substrate during growth, resulting in the deposition of very dense films, exhibiting good adherence, high micro-strain values and small crystallite sizes, which explains the measured high hardness values.
|17:10||In situ XRR measurements during growth of vanadium carbide (VC1-x) thin films|
Authors : Marthe Kaufholz, Baerbel Krause, Sunil Kotapati , Sven Ulrich, Michael Stüber, Tilo Baumbach
Affiliations : ISS, Karlsruher Institute for Technology; ISS, Karlsruher Institute for Technology; ISS, Karlsruher Institute for Technology; IAM-AWP, Karlsruher Institute for Technology; IAM-AWP, Karlsruher Institute for Technology; IAM-AWP, Karlsruher Institute for Technology
Resume : Vanadium Carbide (VC1-x) is a promising candidate for new hard coatings used for tools. For optimizing the coating properties, the relation between the deposition conditions, microstructure formation, and mechanical properties has to be understood. In situ X-Ray Reflectivity (XRR) is a powerful method to investigate the changes in thickness, electron density and roughness during the growth process. Measurements were performed during deposition of several VC1-x thin films on Si at the MPI Beamline at ANKA. Deposition conditions as for example substrate temperature were systematically changed. Pre- and post-growth full specular XRR measurements were conducted. During sputtering the intensity changes e.g. due to the thickness increase were measured at fixed angular position of the detector. For the analysis of the angle- and time-dependent XRR a simulation tool is used based on the Parratt Algorithm. This allows the determination of the deposition rate, changes in roughness and electron density in relation to the sputtering conditions. Furthermore this tool can be adapted to other materials and deposition techniques. First measurements show that the electron density of the VC1-x coatings depends strongly on the plasma properties during the deposition. This might give the possibility of a controlled growth of layers with different electron density by tuning the plasma conditions.
|17:30||Composition, microstructure and properties of pulsed-DC sputtered Cr-B-N films as a function of their boron content|
Authors : D. Pilloud, P. Noyrez, J.F. Pierson
Affiliations : Institut Jean Lamour, CP2S, Université de Lorraine, 54042 Nancy, France
Resume : Transition metal boron nitrides are promising materials for protective coatings due to their ability to combine high hardness, good tribological properties and improved oxidation resistance. Few studies, mainly focused on boron-rich films, have been performed on Cr-B-N coatings. The aim of the present study is to investigate the role of the boron content on the structural features of Cr-B-N films elaborated by pulsed-DC sputter deposition of 3 targets Cr80B20, Cr60B40 and CrB2 in various Ar/N2 mixtures. Compositions were assessed by EPMA and XPS with good accordance. The microstructure of the films was determined by combining XPS, XRD, TEM and FTIR. Mechanical properties of the films have been measured by nanoindentation. Oxidation tests were performed in air up to 700°C and the structure of the resulting films have been analysed by XRD and in-situ FTIR. The present work reveals that with an increase of the nitrogen content, the films elaborated from a Cr80B20 target showed a transition from an amorphous to a nanocomposite structure that comes with a hardness increase. No marked change in the nc-CrN/a-BN nanocomposite structure was evidenced after oxidation treatment. Conversely, the films synthesized with higher boron contents were X-ray amorphous and showed a hardness drop and a depreciated high temperature oxidation resistance. This study emphasizes that the boron concentration is a critical parameter in the optimisation of the properties of Cr-B-N coatings.
|17:50||Impact of nitrogen on phase formation, microstructure and properties of reactively r.f. magnetron sputtered Cr-Zr-O-N thin films|
Authors : S.Spitz, M.Stüber, H.Leiste, S.Ulrich
Affiliations : Karlsruhe Institute of Technology (KIT), Institute for Applied Materials (IAM-AWP), D-76344 Eggenstein-Leopoldshafen
Resume : Novel Cr-Zr-O and Cr-Zr-O-N thin films were deposited by reactive r.f. magnetron sputtering in argon-oxygen and argon-oxygen-nitrogen atmospheres, respectively, in a Leybold Z 550 PVD coating machine. A substrate temperature of maximum 500 °C and a r.f. target power of 500 W was applied. The reactive gas flows of oxygen and/or nitrogen and the r.f. substrate bias were varied systematically. Following a combinatorial approach, thin films with five different elemental compositions from Cr-rich to Zr-rich were obtained in one deposition process by using a segmented Cr-Zr sputtering target. Under specific deposition conditions and within a wide Cr:Zr concentration ratio Cr-Zr-O thin films are grown in a single-phase solid solution corundum type crystal structure. We will focus in this presentation on the impact of additional nitrogen on their growth behaviour, phase formation and phase stability. The elemental composition of the coatings was determined by Electron Probe Micro-Analysis (EPMA). The evolution of the microstructure and phase formation has been studied by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). Vickers microhardness measurements and microindentation data (hardness, Young´s modulus) will be discussed versus the microstructure of these coatings.
|18:10||Preparation peculiarities of Ti-B-C and Ti-B-N thin films by modified magnetron deposition method|
Authors : G.V. Kalinnikov1, R.A. Andrievskii1, V.K. Egorov2
Affiliations : 1 ICP RAS, Chernogolovka, Moscow district, 142432 Russia; 2 IMT RAS, Chernogolovka, Moscow district, 142432 Russia
Resume : Films prepared in frame of Ti-B-C-N system demonstrate heightened hardness and durability. One main way of such films preparation is the magnetron sputtering deposition. Standard procedure of this method is characterized by small value of the diffuse magnetic field near substrate surface. But our preliminary experiments showed that the deposition rate and properties of coatings deposited on substrates were sensitive to direction of the additional magnetic field about the substrate surface plane and its magnitude. So, primary goal of the work was to expose the influence degree of the additional magnetic field parameters on deposition kinetics and properties of coatings for Ti-B-C-N system obtained in the deposition process. Depositions were carried out for Ti-B-C and Ti-B-N triple subsystems on Si and Be substrates. Testing of the prepared coatings showed that the maximum deposition rate for both triple ensembles was achieved when the steady magnetic field was oriented along the substrate surface. Study of a magnetic field influence on properties of coatings belonging to both ensembles showed the films micro hardness increasing on 20% at the field growth from 0 to 0.3 T. The coating element concentration and its thickness was determinated by RBS of He+ and H+ ion beams. Materialographic investigations were executed by electron and optical microscopics methods. Phase and structure features of the ensembles are fixed by methods of X-ray diffractometry.
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