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Thermal stability of Ti/Ni multilayer thin films
Václavík, R. ; Zábranský, L. ; Souček, P. ; Sťahel, P. ; Buršík, Jiří ; Fořt, Tomáš ; Buršíková, V.
In this work, thermal stability and mechanical properties of Ti/Ni multilayer thin films were studied. The multilayer thin films were synthesised by alternately depositing Ti and Ni layers using magnetron sputtering. The thickness of constituent layers of Ti and Ni varied from 1.7 nm to 10 nm, and one coating was deposited by simultaneous sputtering of both targets. Single crystalline silicon was used as a substrate. The effects of thermal treatment on the mechanical properties were studied using nanoindentation and discussed in relation to microstructure evaluated by X-ray diffraction. Annealing was carried out under low-pressure conditions for 2 hours in the range of 100-800 degrees C.
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Compounds in Old Church Slavonic
Zábranský, Lukáš ; Čermák, Václav (advisor) ; Bláhová, Emílie (referee) ; Bauerová, Helena (referee)
In the dissertation Compounds in Old Church Slavonic, the author seeks to shed light on the issue of how to view words formed by composition in the Old Church Slavonic literature. The methodology of processing compounds in Old Church Slavonic is discussed in a separate chapter, which also summarises the recent literature on compounds with the references to key works. It goes on to explain and justify the principles adopted for the analysis of lexemes. Individual chapters, in addition to the various types of composition and the types of compounds divided by the author, also deal with the genre or frequency of specific examples. In the first place it was with a justification defined which lexical units were taken into account in the paper and vice versa, which were not included in the corpus. In the chapter on the methodology, the use of criteria and aspects was justified. Subsequently, a space was devoted to the issue of the so-called connecting morpheme of compounds, its origin and form in specific lexemes, an analysis from a formal point of view. The order of criteria in chapters is determined by their scope, i.e. their applicability to a greater or lesser range of compounds. Statistical data was taken into account in individual groups of lexemes. Subsequently, the compounds were examined in terms of word...
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Dynamic impact wear and impact resistance of W-B-C coatings
Daniel, Josef ; Grossman, Jan ; Buršíková, V. ; Zábranský, L. ; Souček, P. ; Mirzaei, S. ; Vašina, P.
Coated components used in industry are often exposed to repetitive dynamic impact load. The dynamic impact test is a suitable method for the study of thin protective coatings under such conditions. Aim of this paper is to describe the method of dynamic impact testing and the novel concepts of evaluation of the impact test results, such as the impact resistance and the impact deformation rate. All of the presented results were obtained by testing two W-B-C coatings with different C/W ratio. Different impact test results are discussed with respect to the coatings microstructure, the chemical and phase composition, and the mechanical properties. It is shown that coating adhesion to the HSS substrate played a crucial role in the coatings.
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Study of mechanical properties of nanolayered Ti/Ni coatings
Zábranský, L. ; Václavík, R. ; Přibyl, R. ; Ženíšek, J. ; Souček, P. ; Buršík, Jiří ; Fořt, Tomáš ; Buršíková, V.
The aim of the present work was to study the dependence of mechanical properties of Ti/Ni multilayer thin films on the thicknesses of constituent Ti and Ni layers. The multilayer thin films were synthesized by deposition of Ti and Ni layers alternately on single crystalline silicon substrates using direct current magnetron sputtering method. Thicknesses of Ti and Ni layers varied from 1.7 nm to 100 nm. The micro-structure of the multilayer films was studied using X-ray diffraction technique, scanning electron microscopy with focused ion beam technique and transmission electron microscopy. Mechanical properties obtained from nanoindentation experiments were discussed in relation to microstructural observations.
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Characterization of Ta-B-C nanostructured hard coatings
Buršík, Jiří ; Buršíková, V. ; Souček, P. ; Zábranský, L. ; Vašina, P.
Microstructure and mechanical properties of Ta-B-C nanocrystalline layers prepared by magnetron sputtering were studied. DC magnetron sputtering was used to prepare thin layers on rotated substrates. Various deposition parameters were tested. Microstructure of layers was studied by means of scanning and transmission electron microscopy on thin lamellar cross sections prepared using a focussed ion beam. Both undisturbed layers and the volume under relatively large indentation prints (load of 1 N) were observed. The microstructure observations were correlated with mechanical properties characterized by means of nanoindentation experiments in both the static and the dynamic loading regime. Elastic modulus, indentation hardness and fracture resistance of prepared nanostructured coatings were evaluated and discussed.
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Impact resistence on nanocomposite Mo-B-C- and W-B-C coatings deposited using magnetron sputtering technique
Fořt, Tomáš ; Grossman, Jan ; Daniel, Josef ; Sobota, Jaroslav ; Dupák, Libor ; Buršíková, V. ; Zábranský, L. ; Souček, L. ; Mirzaei, S. ; Alishahi, M. ; Vašina, P. ; Buršík, Jiří
Recently, based on attractive mechanical properties of boride and carbide based X2BC ternary compounds (X = Mo, W and Ta) they became subjects of both theoretical calculations and experimental work. In the case of stoichiometric composition, X2BC with X = Mo, W and Ta are very promising candidates for protection of cutting and forming tools due to their unusually stiffness and moderate ductility.\nIn this work we focus on nanostructured Mo-B-C and W-B-C layers grown by magnetron sputtering on high speed steel (HSS) substrates. Mechanical properties of the layers were characterized by nanoindentation experiments in both static and dynamic loading regimes. Elastic modulus, indentation hardness and fracture resistance were evaluated and discussed. The fracture resistance of both Mo-B-C and W-B-C coatings was compared using both indentation and dynamic impact tests.\n
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Compounds in Old Church Slavonic
Zábranský, Lukáš ; Čermák, Václav (advisor) ; Bláhová, Emílie (referee) ; Bauerová, Helena (referee)
In the dissertation Compounds in Old Church Slavonic, the author seeks to shed light on the issue of how to view words formed by composition in the Old Church Slavonic literature. The methodology of processing compounds in Old Church Slavonic is discussed in a separate chapter, which also summarises the recent literature on compounds with the references to key works. It goes on to explain and justify the principles adopted for the analysis of lexemes. Individual chapters, in addition to the various types of composition and the types of compounds divided by the author, also deal with the genre or frequency of specific examples. In the first place it was with a justification defined which lexical units were taken into account in the paper and vice versa, which were not included in the corpus. In the chapter on the methodology, the use of criteria and aspects was justified. Subsequently, a space was devoted to the issue of the so-called connecting morpheme of compounds, its origin and form in specific lexemes, an analysis from a formal point of view. The order of criteria in chapters is determined by their scope, i.e. their applicability to a greater or lesser range of compounds. Statistical data was taken into account in individual groups of lexemes. Subsequently, the compounds were examined in terms of word...
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Compounds in Old Church Slavonic
Zábranský, Lukáš ; Čermák, Václav (advisor) ; Bláhová, Emílie (referee) ; Bauerová, Helena (referee)
In the dissertation Compounds in Old Church Slavonic, the author seeks to shed light on the issue of how to view words formed by composition in the Old Church Slavonic literature. The methodology of processing compounds in Old Church Slavonic is discussed in a separate chapter, which also summarises the recent literature on compounds with the references to key works. It goes on to explain and justify the principles adopted for the analysis of lexemes. Individual chapters, in addition to the various types of composition and the types of compounds divided by the author, also deal with the genre or frequency of specific examples. In the first place it was with a justification defined which lexical units were taken into account in the paper and vice versa, which were not included in the corpus. In the chapter on the methodology, the use of criteria and aspects was justified. Subsequently, a space was devoted to the issue of the so-called connecting morpheme of compounds, its origin and form in specific lexemes, an analysis from a formal point of view. The order of criteria in chapters is determined by their scope, i.e. their applicability to a greater or lesser range of compounds. Statistical data was taken into account in individual groups of lexemes. Subsequently, the compounds were examined in terms of word...
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