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1
Content available remote Przegląd materiałów do zabezpieczeń wodochronnych
EN
In this paper, we consider the design of neutral coated holes in two particular cases when the thick coating itself is altered by the presence of some form of material imperfection. In the first case we consider anti-plane deformations of a linearly elastic solid when the thick coating applied to the hole includes a screw dislocation dipole. In the second case, we investigate the design of neutral coated holes in plane elasticity when the thick coating contains a circular thermal inclusion and the surrounding linearly elastic solid is subjected to uniform remote hydrostatic stresses. The design is achieved by constructing particular forms of the conformal mapping function for the coating itself. Several examples are presented to demonstrate the resulting solutions. Our numerical results show that the existence of the screw dislocation dipole or the circular thermal inclusion in the coating exerts a significant influence on the shape of the neutral coated hole.
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.
5
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.
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 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.
11
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.
13
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.
14
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
EN
Purpose: The paper presents investigation results of the structure and mechanical properties of gradient coatings deposited by cathodic arc evaporation - physical vapour deposition (CAE-PVD) techniques onto the X40CrMoV5-1 hot work tool steel, HS6-5-2 high speed steel and SiAlON tool ceramics. The Ti(C,N), (Ti,Al)N and (Al,Si,Cr) N coatings were investigated. Design/methodology/approach: Microstructure was characterised using scanning and transmission electron microscopy. The phase composition of the investigated coatings was determined by means of the X-ray diffractometer. The chemical concentration changes of the coating components, and the substrate material were evaluated in virtue of tests carried out in the GDOS spectrometer. Tests of the coatings’ adhesion to the substrate material were made using the scratch test method. Findings: It was found out that the structure of the PVD coatings deposited onto all substrates is composed of fine crystallites. The investigations made by use of the glow discharge optical emission spectrometer indicate to the existence of the transition zone between the substrate material and the coating. The results show that all coatings present good adhesion. The critical load LC2, which is in the range 35-90 N, depends on the coating type and substrate. Good adhesion of the coatings deposited to the substrate should be connected with the existence of the transition zone. All the coatings are demonstrated by high hardness. Research limitations/implications: Ti(C,N), (Ti,Al)N and (Al,Si,Cr) N gradient coatings can be applied for cutting tools and hot working tools. Originality/value: Working out and testing PVD coatings obtained by tool ceramic and tool steels is a special future of development direction in a domain of thin coatings.
EN
Purpose: The goal of the presented study was to develop a methodology giving a possibility to predict functional properties of coatings obtained in the PVD and CVD processes on tool materials, based on fractal- and multi-fractal quantities describing their surface. Design/methodology/approach: Effect of process type and deposition conditions on structure and shape of surface, as well as mechanical and service properties of the obtained coatings were determined. Methodology and detailed description of coatings topography obtained in PVD and CVD process on tool materials, including use of the fractal- and multi-fractal geometry based on images obtained on the atomic forces microscope were worked out. Relationships between fractal- and multi-fractal quantities and their mechanical and service properties were determined. Findings: The investigation results confirmed the feasibility to predict hardness and erosion resistance of coatings obtained in the magnetron PVD process, as well as the service properties defined in the cutting ability test for coatings obtained in the arc PVD process and in the high-temperature CVD process, based on the surface fractal dimension Ds value for their surface topography. Practical implications: Determining significant quantitative correlations between fractal quantities defining coatings’ surfaces, as well as their service and/or mechanical properties provides the opportunity to predict their end-user properties. Originality/value: Fractal analysis was applied for characterization of PVD and CVD coatings surfaces.
17
Content available remote Plasma modification of medical implants by carbon coatings depositions
EN
Purpose: The main goal was to work out the technology of deposition of carbon layers onto surface of medical implants made of the AISI316L medical steel. So far the results of carried investigations have proved that layers synthesized in RF PACVD process noticeably improve the biotolerance of the medical steel. Positive experimental results concerning the implementation of carbon layers conducted in the Institute of Materials Science and Engineering of the Technical University of Lodz were the basis for attempt of industrial application of the worked out technology. Design/methodology/approach: Carbon layers were manufactured using radio frequency plasma RF PACVD method. The technology was worked out for the surfaces of the intramedullary nails. The investigations were carried out in order to compare obtained synthesis results with the layers deposited under the laboratory conditions. In this work the following are presented: the surface topography investigation, results of nanohardness and adhesion measurements as well as the raman spectra. Medical examination results were presented in our earlier publications. In the description of obtained investigation results are also presented the preliminary results of the medical treatment effects with the use of intramedullary nails covered with the carbon layer. Findings: Carbon layers manufactured onto intramedullary nails presented good mechanical properties. Applied synthesis parameters made it possible to manufacture uniform film onto whole implant surface. Thickness of the layer was varied in the range of 200 – 400 nm, however total modification area contained 3.5 micrometers. Nails covered with the carbon layer positively passed the tests and were admitted into medical trade turnover. Positive medical treatment results were observed especially in case of patients with affirmed allergies onto alloying components contained in medical steels like chromium and nickel. Research limitations/implications: Significant matter for the examinations had the introduction of the additional control parameters of the plasmo-chemical layers synthesis process. From the point of view of the industrial implementation of technology the fact of limited process efficiency can be. Originality/value: The fundamental value of conducted investigations is the industrial application of the technology of deposition of carbon layers onto intramedullary nails. Currently those products are available in the business offer of MEDGAL Company.
18
Content available remote Optical properties and morphology of PECVD deposited titanium dioxide films
EN
Purpose: The purpose of the present work is to compare the structure and optical properties, with respect to their potential optical applications, of titanium dioxide films synthesized with the PECVD method from two different precursor materials, namely titanium tetrachloride and titanium tetraethoxide (TEOT). Design/methodology/approach: Optical properties as well as thickness of the films were analyzed by means of Variable Angle Spectroscopic Ellipsometry (VASE). Morphology studies were carried out by Scanning Electron Microscopy (SEM) and chemical composition characterisation was performed with the help of Energy Dispersive Spectroscopy (EDS) unit coupled with the electron microscope. Findings: Optical parameters approaching those of titanium dioxide were achieved for both precursors. Studies of morphology show that the films produced from TEOT have favourable, smooth surface in contradiction to broccoli-like structure obtained for the chloride precursor. The type of substance used for titanium oxides synthesis determined chemical composition of the films resulting in their enrichment with either chlorine or carbon, depending on the precursor composition. Practical implications: The optical quality of the films is good enough to suggest their applications in stack multilayer interference filters. The refractive index values of these films advocate their use as high refractive index materials while their low extinction coefficients assure the devices transparency. Originality/value: The work presents deposition rates as well as the films optical properties, chemical composition and morphology in relation to operational parameters of their synthesis. It also provides a comparison of these characteristics for two competitive precursor compounds. Finally, it presents the capability of PECVD method for the deposition of optical coatings onto polymer substrates.
EN
Purpose: The paper presents investigations of the evolution, structure and location of arc spots on the cathode frontal surfaces of two types of industrial arc sources. Design/methodology/approach: The temporal behaviour of cathode spots was recorded with the use of a fast CCD camera. The experiments were performed at four values of arc current, nine compositions of the process atmosphere N2+C2H2 and three pressure ranges of the process atmosphere. Findings: The analysis of the recorded pictures revealed the fine structure of the arc discharge for the investigated range of process conditions. Both temporal and spatial behaviour of cathode spots were different for both investigated arc sources. The correspondence between radial distributions of the cathode spots on the cathode surface and radial distribution of plasma flow elements analysed in the volume of the vacuum chamber was revealed. Research limitations/implications: The paper show experimental methodology that can be used for the research of the specificity of cathode spots movement on the cathodes made from different materials. Originality/value: The originality of the research presented in the paper consists in assigning overall correlation between vacuum-arc source configuration and parameters of vacuum-arc discharge – on the one hand, and space-time behaviour of the arc spots during their movement on the circular cathode surface and radial distribution of excited and ionized atoms of the cathode material in the deposition chamber – on the other.
EN
Purpose: Influence of heat treatment on microstructural changes in slurry TiAlSi coating deposited with 12.5% Si concentration on Ti48Al2Cr2Nb intermetallic alloy and investigation of the influence of Si addition on the structure of obtained coatings is a purpose of this paper. Design/methodology/approach: The research allowed identifying microstructural changes that took place during annealing at 950°C of the TiAlSi coating for 2 to 10h exposure in air. A scope of the research encompassed a microstructural analysis with the use of macro and micro investigation - LM, SEM microscopy, XRD phase analysis and EDS analysis. Findings: The investigation has shown that the thickness of the TiAlSi coatings in initial conditions and after a test was in a range from 30 to 40 ěm. The structure of the silicon-modified aluminide coatings is as following: the outer zone consisting of the TiAl3 phase and titanium silicides / the middle zone consisting of columnar titanium silicides in phase TiAl3 matrix / the inner zone consisting of TiAl2 phase. Basic changes were related to differences in thickness in sublayers. Research limitations/implications: The discussed research proves that main reason of much better protection of TiAlSi coated base alloy is related to high microstructure stability of Si modified in TiAl3 phases. In addition silicon decreases activity of titanium, and in consequence the susceptibility of Al to selective oxidation is much stronger. The presence of Si due to Ti-Si phase generation with high oxidation resistance is presented. Practical implications: The slurry method can be applied in aerospace and automotive industry as low-cost technology in production of aluminide coatings on intermetallics. Originality/value: New method of aluminide coatings deposition on TiAl alloys.
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