Purpose: The aim of this paper was investigated structure and properties of gradient coatings produced in PVD and CVD processes on MCMgAl9Zn1 magnesium alloys. Design/methodology/approach: The following results concern the structures of the substrates and coatings with the application of electron scanning microscopy ZEISS SUPRA 35; 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 magnesium alloys by the PVD and CVD processes show a clear - over 100% - increase of the microhardness, compared to the base material microhardness. The best results of the sliding distance were obtained for the DLC coatings. Practical implications: Achieving of new operational and functional characteristics and properties of commonly used materials, including the Mg-Al-Zn 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 and CVD coatings obtained on an unconventional substrate such as magnesium 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 magnesium alloys.
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Purpose: The aim of this paper is to present the results of the author’s own investigations concerning heat and surface treatment of Mg-Al-Zn magnesium alloys. Design/methodology/approach: The test results presented concern the characteristics of synergic heat and surface treatment impact on the structure and properties of Mg-Al-Zn cast magnesium alloys. The surface treatment of the magnesium alloys was carried out with the use of chemical and physical deposition methods from PA CVD and CAE PVD gas phase and laser surface treatment, including in particular laser feeding of hard ceramic particles into the surface of materials produced, enabling the production of a quasi-composite MMCs (Metal Matrix Composites) structure. The tests of the surface and internal structure of materials with the use of macro- and microscopic methods were made with the use of light, transmission and scanning electron microscopy as well Raman spectrometry and X-ray phase analysis. The physical and mechanical properties of magnesium alloys after the standard heat and surface treatment operations were tested by methods appropriate for the properties. Findings: The results of mechanical and functional properties measurements of heat treated samples confirms, that the performed heat treatment, consisting of solution heat treatment with cooling in water, as well aging with cooling in air, causes strengthening of the MCMgAl12Zn1, MCMgAl9Zn1 and MCMgAl6Zn1 cast magnesium alloys according to the precipitation strengthening mechanism, induced by inhibition of dislocation movement due to the influence of strain fields of the homogeny distributed y-phase Mg17Al12 precipitates. The combination of properly chosen heat treatment with the possibilities of structure- and phase composition modeling of the magnesium alloys matrix using laser feeding provides an additive increase of mechanical and functional properties by significant grain refinement and production of micro-composite layers with homogeny distributed dispersion phases particle and characteristic zone structure. Increase of mechanical and functional properties of the investigated alloys is also possible by creating coatings on the surface from the gas phase. Practical implication Achieving of new operational and functional characteristics and properties of commonly used materials, including the Mg-Al-Zn 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 originality of this paper consists in the presentation of a very extensive knowledge related to the methods of structure and properties forming of the surface of Mg-Al-Zn alloys, supported by the results of wide author’s research.
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Purpose: The aim of this paper is the presentation of developed computational model build with use of artificial neural networks. This model describes the influence of PVD and CVD coatings properties on the cutting edge durability from sialon tool ceramics covered with these layers. Design/methodology/approach: Obtained model has the ability to compute the durability of the PVD and CVD coatings coated on sialon tool ceramics blades determined in technological cutting trials of grey cast iron, basing on PVD and CVD coatings microhardness, thickness, grain size and their adhesion to the substrate. Findings: Results of researches, performed with use of computational model, revealed, that the greatest influence on the durability of coated sialon tool ceramics blades have the adhesion to the substrate. Smaller influence on blades durability has the size of grains. Minor influence on the cutting tool from other properties was obtained. Practical implications: Achieved results indicates, that the best coating’s adhesion to the substrate for coating material selection and design of PVD and VD coatings deposition process should have priority in implementation. Originality/value: Obtainment and utilisation of computational model builded with use of artificial intelligence methods
In the work it was demonstrated that the exploitative stability of edges from tool ceramics and sintered carbides coated with gradient and multilayer PVD and CVD coatings depends mainly on the adherence of the coatings to the substrate, while the change of coating microhardness from 2300 to 3500 HV0.05, the size of grains and their thickness affect the durability of the edges to a lesser extent. It was found that some coatings showed a fine-grained structure. The coatings which contained the AlN phase with hexagonal lattice showed a considerably higher adhesion to the substrate from sialon ceramics rather than the coatings containing the TiN phase. Better adherence of the coatings containing the AlN phase with hexagonal lattice is connected with the same kind of interatomic bonds (covalent) in material of both coating and ceramic substrate. In the paper the exploitative properties of the investigated coatings in the technological cutting trials were also determined. The models of artificial neural network, which demonstrate a relationships between the edge stability and coating properties such as: critical load, microhardness, thickness and size of grains were worked out.
PL
W pracy wykazano, że trwałość eksploatacyjna ostrzy skrawających z ceramiki narzędziowej i węglików spiekanych pokrytych gradientowymi i wielowarstwowymi powłokami PVD oraz CVD zależy głównie od przyczepności powłok do podłoża, natomiast zmiana mikrotwardości w zakresie od 2300 do 3500 HV0.05. wielkości ziarn oraz ich grubości w mniejszym stopniu wpływają na trwałość ostrzy. Powłoki wykazują drobnoziarnistą strukturę. Powłoki zawierające fazę AlN o sieci heksagonalnej wykazują lepszą przyczepność do sialonowego podłoża niż powłoki zawierające fazę TiN. Lepsza przyczepność powłok zawierających fazę A1N o sieci heksagonalnej związana jest z takim samym rodzajem wiązań międzyatomowych (kowalencyjnych) w materiale powłoki i ceramicznego podłoża. W pracy określono także własności eksploatacyjne powłok w technologicznej próbie toczenia. Zależności pomiędzy trwałością ostrza a własnościami powłok takimi jak obciążenie krytyczne, mikrotwardość, grubość i wielkość ziarna określono z zastosowaniem sztucznych sieci neuronowych.
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Purpose: The purpose of the paper is to present the representative examples for the own scientific research in the area of the forming of the structure and properties of engineering materials including biomaterials, their properties testing and microstructure characterisation and modelling, simulation and prediction of the properties and structure of these materials after selected materials processing technologies. Design/methodology/approach: The main areas of the scientific interests reported in this paper on the basis of the own original research include forming of structure and properties of engineering materials including biomaterials using advanced synthesis and materials processing technologies and nanotechnologies, engineering materials including biomaterials properties testing and microstructure characterisation using very advanced contemporary research methodologies including electron microscopy, modelling, simulation and prediction of properties and structure of engineering materials including biomaterials using advanced methods of computational materials science including artificial intelligence methods. Findings: A general character of the paper concerning many aspects of material science research enabled a detailed description of research methodology and details concerning research results. Detailed information is included in many detailed cited works. Practical implications: Presented research results can be used in practice. Originality/value: The paper presents numerous research results which Has been made during last years generalising the achievements of the research team directed by the author.
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