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EN
Purpose: The aim of the study was to investigate the possibility of sintering raw (natural) halloysite and pure halloysite to produce porous ceramic preforms, and determination of sintering temperature based on the results of investigations into thermal effects, linear changes and phase transitions. Design/methodology/approach: Due to mullitisation ability of halloysite at high temperature, alternative applications based on the sintering technology (including the production of reinforcement of metal matrix composites) are being searched for. Pure halloysite and Dunino halloysite were selected for the study. Findings: Pure halloysite, characterized by low impurities, dimensional stability during sintering, softening temperature above 1500ºC and ability to transform into mullite at temperatures above 950ºC could be used as a base for the production of sintered, porous mullite preforms. Research limitations/implications: Presence of impurities in Dunino halloysite, contribute to the shift of the sintering temperature towards lower temperatures and caused a rapid and uncontrolled shrinkage of the sample and the appearance of the softening temperature at 1300ºC. Practical implications: Based on the research of thermal (DTA/TG, linear changes in high-temperature microscopy) and XRD studies it is possible to determine the sintering temperature of pure halloysite to manufacture the porous mullite preforms with open porosity. Originality/value: The received results show the possibility of obtaining the new mullite preforms based on pure halloysite.
EN
Purpose: Among the technologies that play a crucial role in the current stage of development of Industry 4.0 conventional powder engineering technologies are of great importance. Based on a comprehensive literature review, conventional technologies using the powders of metals, their alloys and ceramics are described. Development perspectives of the most widespread among them were indicated. Design/methodology/approach: Extensive literature studies on conventional powder engineering technologies have been carried out. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: In addition to the presentation of conventional sintering technological methods, sintering mechanisms in solid-state and liquid phase sintering which accounts for 90% of the commercial value of sintered products are presented. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them conventional powder engineering technologies play a key role in current industry development. For this reason, these technologies have been characterized in detail on the basis of available literature sources.
EN
Purpose: The paper is a comprehensive review of the literature on manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics. Design/methodology/approach: Extensive literature studies on manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics have been carried out. The paper is illustrated with examples of various structure images obtained as part of research of engineering materials made by authors with powders. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: The manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics as the advanced digital production (ADP) technologies are proves the highest possible potential and relatively good attractiveness, as well as their fully exploited attractiveness or substantial development opportunities in this respect. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them manufacturing technologies thick-layer coatings on various substrates and manufacturing gradient materials using powders of metals, their alloys and ceramics are becoming very important among product manufacturing technologies. They are an essential part of powder engineering.
EN
Purpose: The paper is a literature review indicating the importance of powder engineering in the modern stage of Industry 4.0 development. 47 technologies for the manufacturing and use the powders of metal and their alloys and ceramic in the manufacturing of products are indicated. All those technologies were compared in terms of their potential and attractiveness, pointing to their development trends. The focus was solely on powder production methods. Other technologies will be discussed in other papers in the powder engineering cycle. Design/methodology/approach: The authors' considerations are based on an extensive literature study and the results of the authors' previous studies and empirical work. In order to compare the analyzed technologies, the methodology of knowledge engineering are used, including the own method of contextual matrices for comparative analysis of a large set of technologies by presenting them on a dendrological matrix. Findings: The most interesting intellectual achievements contained in the paper include presentations of the authors' original concepts regarding the augmentation of the Industry 4.0 model. Material processing technologies occupy an important place in it, among them powder engineering technologies, both conventional and additive. The most attractive and promising development technologies in powder engineering are identified. Originality/value: The originality of the paper is associated with the novelty of the approach to analysing powder engineering, an indication of its importance for the development of the Industry 4.0 idea, where progress does not depend only on the development of IT technologies. It is also not true that from among technologies only additive technologies play a key role. Using avant-garde analyses in the field of knowledge engineering, the most avant-garde technologies of powder engineering are pointed out.
EN
Purpose: The paper is a comprehensive review of the literature on additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics. Design/methodology/approach: Extensive literature studies on conventional powder engineering technologies have been carried out. By using knowledge engineering methods, development perspectives of individual technologies were indicated. Findings: The additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics as the advanced digital production (ADP) technologies are located in the two-quarters of the dendrological matrix of technologies "wide-stretching oak" and "rooted dwarf mountain pine" respectively. It proves their highest possible potential and attractiveness, as well as their fully exploited attractiveness or substantial development opportunities in this respect. Originality/value: According to augmented holistic Industry 4.0 model, many materials processing technologies and among them additive and hybrid technologies for products manufacturing using powders of metals, their alloys and ceramics are becoming very important among product manufacturing technologies. They are an essential part not only of powder engineering but also of the manufacturing development according to the concept of Industry 4.0.
EN
Purpose: The purpose of this study is to present the author's method of planning the procedure of immediate implant-prosthetic restoration in place of a tooth qualified for removal by performing a surgical template and implant-prosthetic restoration based on data obtained in the CBCT test and intraoral scanning 3D model. Design/methodology/approach: The method of planning the implant surgery through the design and manufacture of surgical templates and implant prostheses performed before the start of medical procedures was described on the basis of actual clinical data from patients with anterior segment teeth qualified for extraction for reasons of complications after endodontic treatment. The placement of the implant was planned using virtual reality, where the bone model and the virtual soft tissue model were combined, which made it possible to perform a surgical template and prosthetic implant restoration. For the manufacturing, 3D printing as stereolithography SLA and selective laser sintering SLS for the surgical template manufacturing and CNC milling in the case of the prosthetic implant were used for restoration. Findings: The method allows planning the implant position based on two connected bone and soft tissue models and allows to design and manufacture a surgical guide. In this way, it becomes possible to place implants in the patient's bone during surgery procedure in the planned position and to install the prosthetic implant restoration in the form of an individual abutment and a PMMA crown during the same procedure in the surgical part. Practical implications: Thanks to the method of computer-aided design/manufacturing CAD/CAM production of surgical templates and prosthetic restoration based only on digital models and the planned position of the implant, it is possible to carry out the procedure of immediate tooth extraction and replacement with permanent prosthetic restoration. The whole process is based on the CBCT test performed at the beginning. The presented method allows shortening the procedure time by four times and the rehabilitation time by 3-6 months when performing the procedure in a minimally invasive manner. Originality/value: This article presents the original design and production method of surgical guides. It allows for precise planning of the implant position and transfer of this data to the patient's mouth during the procedure, enabling permanent prosthetic restoration before starting medical procedures.
EN
Purpose: The paper presents the issues of designing the maintenance of materials and products in accordance with the idea of Industry 4.0. The author's views on the need for augmentation of the Industry 4.0 model were also presented, as well as the author's original concept that hybrid activities in predictive maintenance and condition-based maintenance should be preceded by designing material, maintenance & manufacturing 3MD at the stage of the product's material designing and technological designing. The 3MD approach significantly reduces the frequency of assumed actions, procedures and resources necessary to remain the condition of this product for the longest possible time, enabling it to perform the designed working functions. Examples of own advanced research on several selected, newly developed materials, used in very different areas of application, confirmed the validity of the scientific hypothesis and the relationship between the studied phenomena and structural effects and the working functions of products and their maintenance and indicated that material design is one of the most important elements guaranteeing progress production at the stage of Industry 4.0 of the industrial revolution. Design/methodology/approach: The author's considerations are based on an extensive literature study and the results of the author's previous study and empirical work. Each of the examples given required the use of a full set of research methods available to modern material engineering, including HRTEM high-resolution transmission electron microscopy. Findings: The most interesting intellectual achievements contained in the paper include presentations of the author's original concepts regarding the augmentation of the Industry 4.0 model, which has been distributed so far, which not only requires augmentation but is actually only one of the 4 elements of the technology platform of the extended holistic model of current industrial development, concerning cyber-IT production aided system. The author also presents his own concept for designing material, maintenance and manufacturing 3MD already at the stage of material and technological design of the product, eliminating many problems related to product maintenance, even before they are manufactured and put into exploitation. Detailed results of detailed structural researches of several selected avant-garde engineering materials and discussion of structural changes that accompanying their manufacturing and/or processing are also included. Originality/value: The originality of the paper is associated with the novelty of the approach to analysing maintenance problems of materials and products, taking into account the requirements of the contemporary stage of Industry 4.0 development. The value of the paper is mainly associated with the presentation of original issues referred to as findings, including the concept of augmentation of the Industry 4.0 model and the introduction and experimental confirmation of the idea by designing material, maintenance and manufacturing 3MD.
EN
Purpose: In the paper, the own original achievements and a mature view of the current development of advanced nanotechnology materials are presented. Design/methodology/approach: The paper should be treated as an auto-review of the own research in the area. The paper is preceded by a short historical sketch and the development of the concept and meaning of nanotechnology and nanostructured materials. Respectively, the following issues are described: the nanocomposites containing carbon or halloysite nanotubes, graphene and metallic nanowires, nanostructured coatings and surface zones of engineering materials, a creation of the nanometric components of the structure of massive materials, nanocomposite materials designed mainly for use in regenerative medicine and regenerative dentistry. Practical implications: In final remarks, the attention is paid to applications of nanotechnology in many products sought on the market and improve their properties and applicability.
EN
Purpose: The purpose of this investigation was to determine the changes in the surface layer (Inconel 625), obtained during the laser treatment of tool-steel alloy for hot work by the use high-power fibre laser. Design/methodology/approach: Observations of the layer structure, HAZ, and substrate material were made using light and scanning microscopy. The composition of elements and a detailed analysis of the chemical composition in micro-areas was made using the EDS X-ray detector. The thickness of the resulting welds, heat affected zone (HAZ) and the contribution of the base material in the layers was determined. Findings: As a result of laser cladding, using Inconel 625 powder, in the weld overlay microstructure characteristic zones are formed: at the penetration boundary, in the middle of weld overlay and in its top layer. It was found that the height of weld overlay, depth of penetration, width of weld overlay and depth of the heat affected zone grows together with the increasing laser power. Practical implications: Laser cladding is one of the most modern repair processes for eliminating losses, voids, porosity, and cracks on the surface of various metals, including tool alloys for hot work. Laser techniques allow to make layers of materials on the repaired surface, that can significantly differ in chemical composition from the based material (substrate material) or are the same. Originality/value: A significant, dynamic development in materials engineering as well as welding technologies provides the possibility to reduce the cost of production and operation of machinery and equipment, among others by designing parts from materials with special properties (both mechanical and tribological) and the possibility of regeneration of each consumed element with one of the selected welding technologies.
EN
The paper presents the results of mechanical properties research, fractographic investigations of fractures and microstructure of experimental high-strength high-manganese X98MnAlSiNbTi24–11 and X105MnAlSi24–11 TRIPLEX type steels. In order to determine the mechanical properties of the tested steels, microhardness tests and a static tensile test were performed, and yield stress, tensile strength and elongation of the tested steels were determined. The performed microstructure tests of the analysed steels using light microscopy allowed for the identification of austenitic-ferritic structure with the participation of carbides. It was found that the structure of both tested steels, which have undergone hot rolling followed by water cooling, consist of austenite grains with numerous annealing and deformation twins along with ferrite bands. The investigated steels are characterized by the mixed fractures of formed after a static tensile test after forging where there are areas of ductile fracture with small areas of transcrystalline and intergranular brittle fractures. The fractures after a static tensile test and after hot rolling and cooling in water have a dimple morphology characteristic of plastic fractures. The increase in hardness after thermomechanical treatment and after a static tensile test is caused by strain hardening affecting the achieved values of strength, yield point and hardness. The obtained research results allow to assess the impact of both the chemical composition and the applied thermomechanical treatment technology on the properties of newly developed steels.
PL
Celem pracy było określenie właściwości mechanicznych oraz plastycznych w powiązaniu z mikrostrukturą nowoopracowanych stali wysokomanganowych X98MnAlSiNbTi24–11 i X105MnAl- Si24–11 typu TRIPLEX po walcowaniu na gorąco w skali półprzemysłowej i chłodzeniu w wodzie. Uzyskane wyniki badań pozwolą na ocenę wpływu zarówno składu chemicznego, jak i zastosowanej technologii obróbki cieplno-mechanicznej na właściwości badanych stali.
EN
Purpose: The article deals with one of the completely new groups of composite inorganic nanostructured materials used in the form of surface layers, characterised by unique properties, such as transparency over 84.4% in the field of visible light waves, anti-reflective and electrical properties comparable to semiconductors. Design/methodology/approach: A technology for producing such layers containing not less than 5% of silver nanowires by mixing a colloid containing silver nanowires from fragmented agglomerates by ultrasound homogeniser with the polymer dissolved in chloroform with good bonding to the polymer matrix and of good quality was developed. Findings: It was shown that increasing the content of silver nanowires to 30% in composite layers causes an increase in the refractive coefficient from 1.9 to 2.2 and a decrease in light transmission from 88.1 to 81.9% and a decrease in the value of light reflection from 11.1% up to 6.7%. With an increased content of silver nanowires, these layers show better electrical properties, and the width of the energy gap is reduced from 3.93 eV to 1.60 eV. Composite layers with a mass fraction greater than 5% of silver nanowires show properties analogous to semiconductors despite the metallic nature of their conductivity. Research limitations/implications: The use of silver nanowires as a reinforcement of transparent nanocomposite layers with a poly(methyl methacrylate) PMMA matrix improves selected optical and electrical properties as a result of the uniform distribution of the reinforcing phase in the matrix material. Originality/value: The influence of the content of silver nanowires, layering conditions, applied methods of dispersing silver nanowires in the matrix material on the structure and properties of newly developed nanocomposite layers was determined.
EN
Purpose: The publication aims to find the relationship between the proliferation of surface layers of living cells and the deposition of thin atomic layers deposition ALD coatings on the pores internal surfaces of porous skeletons of medical and dental implant-scaffolds manufactured with the selective laser deposition SLS additive technology using titanium and Ti6Al4V alloy. Design/methodology/approach: The extensive review of the literature presents the state-of-the-art in the field of regenerative medicine and tissue engineering. General ageing of societies, increasing the incidence of oncological diseases and some transport and sports accidents, and also the spread of tooth decay and tooth cavities in many regions of the world has taken place nowadays. Those reasons involve resection of many tissues and organs and the need to replace cavities, among others bones and teeth through implantation, more and more often hybridized with tissue engineering methods. Findings: The results of investigations of the structure and properties of skeleton microporous materials produced from titanium and Ti6Al4V alloy powders by the method of selective laser sintering have been presented. Particularly valuable are the original and previously unpublished results of structural research using high-resolution transmission electron microscope HRTEM. Particular attention has been paid to the issues of surface engineering, in particular, the application of flat TiO2 and Al2O3 coatings applied inside micropores using the atomic layers deposition ALD method and hydroxyapatite applied the dip-coating sol-gel method, including advanced HRTEM research. The most important part of the work concerns the research of nesting and proliferation of live cells of osteoblasts the hFOB 1.19 (Human ATCC - CRL - 11372) culture line on the surface of micropores with surfaces covered with the mentioned layers. Research limitations/implications: The investigations reported in the paper fully confirmed the idea of the hybrid technology of producing microporous implants and implant-scaffolds to achieve original Authors’ biological-engineering materials. The surface engineering issues, including both flat-layered nonorganic coatings and interactions of those coverings with flat layers of living cells, play a crucial role. Originality/value: Materials commonly used in implantology and the most commonly used materials processing technologies in those applications have been described. Against that background, the original Authors' concept of implant-scaffolds and the application of microporous skeleton materials for this purpose have been presented.
EN
Purpose: The purpose of this article is to synthesized NiO nanostructures by sol-gel method and characterized them for use in dye sensitized solar cells. For this purpose, a paste prepared from nanoparticles was prepared and screen printed on a glass substrate with the FTO layer. Design/methodology/approach: Nickel oxide nanoparticles was synthesized with participation of nickel (II) nitrate hexahydrate and citric acid. The prepared nanopowder has been subjected to structural analysis using a transmission electron microscope (TEM). Scanning Electron Microscopic (SEM) images were taken with a Zeiss Supra 35. Qualitative studies of chemical composition were also performed using the Energy Dispersive Spectrometer (EDS). The structure of nickel oxide was investigated by X-ray crystallography. An average crystallite size were calculated using Scherrer method and Williamson-Hall analysis. Light harvesting efficiency LHE was calculated from measured absorbance. Findings: The uniform nickel oxide nanoparticles with spherical shape were successfully produced by sol-gel method. The diameter of the as prepared nanoparticles does not exceed 25 nm which is confirmed by the XRD and TEM analysis. The light harvesting efficiency of the electrode in the entire studied range it’s over 90%. Therefore the NiO can be an attractive alternative to the most commonly used TiO2. Research limitations/implications: The next step in the research will be to investigate the ZnO/NiO composite on the properties of the photoelectrode of dye sensitized solar cell. Practical implications: The unique properties of produced NiO nanostructural materials have caused their interest in such fields as medicine, transparent electronics and photovoltaics. Originality/value: The NiO nanoparticles were prepared using sol-gel method and then effectively used in the photoanode of dye sensitized solar cell.
EN
Purpose: The article concerns the development of completely new groups of composite materials that can be used to produce functional replacements for damaged bones or teeth. Design/methodology/approach: A selective laser sintering was used to produce the reinforcement of those materials from titanium and its Ti6Al4V alloy in the form of skeletons with pores with adjustable geometric features. The matrix of those materials is either air or crystallised from the liquid AlSi12 or AlSi7Mg0.3 alloys condition after prior vacuum infiltration or human osteoblast cells from the hFOB 1.19 (Human ATCC - CRL - 11372) culture line. Findings: The porous material may be used for the non-biodegradable scaffold. After implantation into the body in the form of an implant-scaffold one, it allows the natural cells of the patient to grow into the pores of the implant, and it fuses with the bone or the appropriate tissue over time. The essential part of the implant-scaffold is the porous part inseparably connected with the core of solid materials. Into pores can grow living cells. Research limitations/implications: Biological-engineering composite materials in which natural cells were cultured in the pores in the laboratory next are combined as an artificial material with the natural cells of the patient in his/her body. Practical implications: The hybrid technologies of the all group of those materials were obtained and optimised. Numerous structure research was carried out using the most modern research methods of contemporary materials engineering, and mechanical tests and biological research involving the cultivation of natural cells were realised. Originality/value: The results of the research indicate the accuracy of the idea of implementing a new group of biological-engineering materials and the wide possibilities of their application in regenerative medicine.
16
Content available Wirtualne laboratorium inżynierii materiałowej
PL
Artykuł opisuje Wirtualne Laboratorium Inżynierii Materiałowej Instytutu Materiałów Inżynierskich i Biomedycznych w Politechnice Śląskiej. Jest to otwarte środowisko naukowo-badawczo-symulacyjne pomocne w realizacji zadań dydaktycznych i naukowych z dziedziny nauki o materiałach. Laboratorium jest zbiorem symulacji i trenażerów odwzorowują budowę, zasadę działania, funkcjonalność i metodykę obsługi sprzętu badawczego zainstalowanego i dostępnego w rzeczywistych laboratoriach naukowych. Zastosowanie wirtualnego sprzętu, który jest praktycznie niezniszczalny, tanie w eksploatacji i łatwy w użyciu zachęca studentów i pracowników naukowych do niezależnych badań i doświadczeń w sytuacjach, gdy możliwości ich realizacji w prawdziwym laboratorium śledcze będą ograniczone ze względu na wysokie materiału kosztów, trudności w dostępie do rzeczywistych urządzeń lub potencjalnego ryzyka jego uszkodzenia.
17
Content available remote Virtual laboratory methodology in scientific researches and education
EN
Purpose: This article is presenting the Material Science Virtual Laboratory. Developed laboratory is an open scientific, investigative, simulating and didactic medium helpful in the realisation of the scientific and didactic tasks in the field of material Science. It is implemented in the Institute of Engineering Materials and Biomaterials of Silesian University of Technology in Gliwice, Poland. Design/methodology/approach: The laboratory is a set of testers and training simulators, set in the Virtuality and created in several languages and the programming techniques, which interprets the properties, functionality and manual rules of actual equipment installed and accessible in the real science labs of scientific universities. Findings: Application of the equipment, that is practically imperishable, cheap in exploitation and ease in the use encourages students and scientific workers to independent audits and experiments in places, where the possibilities of their performance in the real investigative laboratory will be restricted because of the high material costs, difficult access to real equipment or the possible peril of his impairment. Research limitations/implications: The proposed solutions allow the utilisation of the developed virtual environment as a new medium in both, the scientific work performed remotely, as well as in education during classes. Practical implications: The usage possibilities of the virtual laboratory are practically unrestricted; it can be a foundation for any surveys, course or training plan. Originality/value: The project of the virtual laboratory corresponds with the global tendency for expand the investigative and academic centres about the possibilities of training and experiments performance with use of the virtual reality. This enriches investigation and training programmes of the new abilities reserved so far exclusively for effecting only on actual equipment.
EN
Purpose: of this research was examination Al2O3 thin film obtained with two different method, by sol-gel and ALD, and comparison the surface morphology and structure of deposited thin films. The films deposited on the monocrystalline silicon were tested for their suitability for use in silicon solar cells. Design/methodology/approach: Trimethylaluminum (TMA) was used as a precursor of Al2O3 which is reacted with water enabled the deposition of thin films by ALD method. By the sol-gel method the aluminium tri-sec butoxide (TBA) was used as a precursor to obtain Al2O3 thin films. The aluminium oxide solutions prepared by sol-gel method were deposited by spin coating technique. Examination of the structure and morphology of the surface of the Al2O3 thin films deposited by sol gel and ALD method were performed using atomic force microscope and transmission electron microscope. For the analysis of surface topography deposited thin films atomic force microscope XE-100 from Park Systems was used. Qualitative analysis of the chemical composition was carried out using an energy dispersion spectrometer (EDS). The detailed structural studies were conducted using a Titan 80-300 scanning-transmission electron microscope S/TEM from the FEI Company. Detailed research on the structure of the deposited Al2O3 thin films were performed. The HRTEM images and diffraction SAED were recorded. Findings: The small atoms clusters of a width less than 20 nm were documented. The thin film deposited by spin-coating technique on silicon substrate with 3000 rpm is characterized by RMS and Ra values of, respectively, 0.26 and 0.2 nm. RMS was defined as rough mean square parameter and Ra was defined as the arithmetic mean deviation of the profile from the mean line. An analysis of the frequency histograms of irregularities of the thin film obtained by the spin coating on a silicon substrate at 3000 rpm shows that a large part of them does not exceed 0.5 nm, and the single irregularities reach up to 2.2 nm. When comparing the AFM pictures with the thin films deposited by ALD technique and spin-coating it has been found that the thin films obtained on polished silicon substrates are similar in morphology. The EDS spectra shows the characteristic for oxygen (0.525 keV) and aluminum (1.486 keV) reflections derived from the thin film. In Al2O3 thin film obtained by ALD method the occurrence of α phase of aluminum oxide with a hexagonal structure was identified, just like in the case of thin film deposited by sol-gel. Practical implications: Known aluminium oxide properties and the possibility of obtaining a uniform thin layer show that it can be good material for different application. Precise description of the properties of Al2O3 is very important, since this material is one of the most frequently used in catalyst industry, in medicine, electronics and photovoltaics, as well as a protective layer. The Al2O3 thin film can act as passive and anti-reflective layer simultaneously in silicon solar cell. Using this thin film can simplify the technology of manufacturing silicon solar cells Originality/value: The paper presents researches of aluminium oxide thin films deposited by sol-gel and atomic layer deposition method on monocrystalline silicon.
EN
The work presents the results of investigations of the structure and phase composition of newly developed high manganese X98MnAlSiNbTi24–11 steel of TRIPLEX type. The average density of such steel is 6.67 g/cm3, which is less than for typical structural steels by even 15%. A preliminary analysis of phase composition and structure allows to find an austenitic γ-Fe(Mn, Al, C) structure in the investigated steel with uniformly distributed ferritic α-Fe(Mn, Al) areas elongated towards the boundaries of austenite grains and numerous carbides with differentiated chemical composition and varied size. Nb- and Ti-based complex carbides are dominant in the steel. The investigations of the chemical composition of the carbides revealed in the matrix allow to identify with high probability dispersive κ-(Fe, Mn)3AlC carbides with the nanometric size of approx. 10÷160 nm, which has to be yet confirmed with electron transmission microscopy methods. Fe, Mn and Al as well as small amounts of Nb, Ti and Si are contained in such carbides. The occurrence of aluminium carbonitrides with a fraction of Nb and Ti was also revealed. The size of the above Nb and Ti carbides revealed in solid specimens in the matrix of the studied steel is between approx. 10 nm to 15 μm. X-ray diffraction examinations of carbide isolates prepared by the method of chemical dissolution in HCl showed the existence of NbTiC2 carbides in the studied steel. The diffraction examinations of solid specimens revealed, apart from austenite and ferrite, also the existence of TiC carbides and such initially classified as Mn3.6C0.4 type.
PL
Celem pracy była charakterystyka struktury i składu fazowego nowoopracowanej stali wysokomanganowej X98MnAlSiNbTi24–11 typu TRIPLEX zawierającej dodatki stopowe Ti i Nb przy dużej zawartości węgla.
EN
The paper presents the results on the wear resistance of PVD coatings on cutting inserts made from sintered carbide and sialon ceramics. The exploitative properties of coatings in technological cutting trials were defined in the paper, which also examined the adhesion of coatings to the substrate, the thickness of the coating, and the microhardness. As a result, it was found that isomorphic coating with AlN-h phase of covalent interatomic bonds exhibits much better adhesion to the sialon substrate than isomorphic coating with titanium nitride TiN. These coatings assure the high wear resistance of the coated tools, and the high adhesion combined with the high microhardness and fine-grained structure assure an increase in the exploitative life of the coated tools. In the case of coatings on substrate made from sintered carbide, there was a significant influence on the properties of the tools coated with them as concerns the existence of the diffusion zone between the substrate and the coating.
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