National Repository of Grey Literature 121 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Titanium and its alloys in aviation
Černota, Jan ; Adam, Ondřej (referee) ; Němec, Karel (advisor)
This bachelor thesis deals with the issue of the use of titanium and its alloys in aviation. First, it deals with titanium as a light metal, its history, occurrence, use, manufacture, and properties. Then about its alloys, their division, and the characteristics of individual alloys, considering their utility for aerospace applications. The main part deals with the use of titanium and its alloys in the aerospace industry, where the performance requirements of materials used in aviation are summarised, how titanium meets these properties and for which components titanium is most often used. The thesis also predicts the development of the use of these materials in the aerospace industry.
Kinetics of fatigue crack propagation in steels P91 and P92
Kander, Jan ; Němec, Karel (referee) ; Věchet, Stanislav (advisor)
The main subject of this master’s thesis was to evalute inluence of loading cycle asymmetry and long-term thermal exposure on fatigue crack growth rate in martensitic P91 and P92 steels. Experiments were carried out in Material and metallurgical research Ostrava Ltd. and their main aim was to study the influences of different loading cycle asymmetries (R = 0,1 and R = 0,6) as well as 5000 hours/600 °C (P91) respectively 5000 hours/650 °C (P92) of thermal exposure on fatigue crack growth rate.
Pyrolytic graphite
Chýlková, Adéla ; Adam, Ondřej (referee) ; Němec, Karel (advisor)
The purpose of this bachelor thesis was to write a literature search summarizing knowledge about carbon-based materials and experimental determination of thermal expansion and thermal balance of samples of various types of graphite and evaluation of measured data. The research part of the work describes most of the currently known types of carbonaceous materials, with a more thorough study of pyrolytic graphite. The whole next chapter was devoted to a more thorough study of pyrolytic graphite. The second part of the thesis is focused on the experimental determination of thermal expansion and thermal balance on selected graphite samples (natural, expanded, pressed expanded and pyrolytic graphite). We used dilatometric analysis and thermogravimetry to solve this task. Finally, the measurement data were processed into graphs and relevant tables and conclusions were deduced.
Casting defect analysis in steel ingot
Krupica, Roman ; Němec, Karel (referee) ; Jan, Vít (advisor)
This thesis deals with the problematics of ingot casting, factors affecting the quality of ingots and defects occurring in them. The first part defines steel casting, defects of steel, their classifications and causes. The other part of the thesis focuses on the laboratory analysis of ingot samples and metallographic characterization of defects.
Cold weapons
Střechovský, Jan ; Němec, Karel (referee) ; Molliková, Eva (advisor)
The aim of this bachelor thesis is a summary of relevant information concerning cold arms. Concerning the amount of content of this topic, this thesis is focused on general knowledge regarding the types, usage and development of cold arms, with mentioning some interesting and less known facts. It also contains deeper analysis of some chosen cold arms or key parts in their manufacture process.
Damascus Steel
Czudek, Szymon ; Němec, Karel (referee) ; Molliková, Eva (advisor)
This bachelor thesis briefly deals with the characterization of iron-based material and describes the process of steel production and raw material used in this process. In the next part, this thesis is about the history of damascus steel, the processes and methods of producing this type of steel and the properties it recieve through these processes. The next chapter discuss specific usage of this material nowadays and in the end it is about other materials that are often erroneously considered for a kind of damascene steel.
The materials for firearms barells
Mrózek, Jan ; Molliková, Eva (referee) ; Němec, Karel (advisor)
The aim of this Bachelor thesis is to summarise information about development and basic description of individual parts of barrel firearms and appropriate use of materials for their production. The content of this thesis are also methods of surface treatment of the barrel rifling. In conclusion, the thesis describes weapon life and deterioration of barrel firearms.
History of Iron and steelworks Třinecké Železárny
Niemczyk, Roman ; Němec, Karel (referee) ; Věchet, Stanislav (advisor)
The bachelor´s thesis is a technical summary and it is describing the history of Třinecké železárny since its creation in the 1850s to the present. The history of iron processing is briefly described. Furthermore, the thesis focuses to manufacturing process of Třinecké železárny and also to iron and steel production technology. At the last part are decribed typical products of Třinecké železány and future prospects of ironworks.
Manufacture of knives and their heat treatment
Bukvic, Tomáš ; Doležal, Pavel (referee) ; Němec, Karel (advisor)
This bachelor thesis deals with manual small series production of knives. It presents an overview of used cutlery steels and ushers their characteristics. It deals with the choice of blade geometry and material for a particular knife application. Furthermore, it initiates into the issue of heat treatment of knives, which is absolutely necessary for their functionality. The conclusion includes the documentation of the kitchen knife manufacturing process, which was made for the purpose of this thesis.
Structure and mechanical properties of magnesium materials processed by HPT
Poloprudský, Jakub ; Němec, Karel (referee) ; Doležal, Pavel (advisor)
This thesis is focused on processing of pure magnesium by high pressure torsion method (HPT). This process belongs to the group of intensive plastic deformation methods (SPD). SPD methods are in the centre of scientific interest for several decades. Theoretical part of this thesis puts an effort to summarize basic knowledge and principles of SPD methods with extra focus on method HPT. As theoretical part continues magnesium as technical material is presented. Influence of SPD on use and properties of pure magnesium is then presented. This trend is further developed in effort to describe the effect of individual HPT process variables on the properties of pure magnesium and its alloys. Focus of practical part of this thesis is in influence of number of revolutions. Samples were processed at 1/8, 1/4, 1/2, 1, 4 and 8 turns at room temperature. Speed of process was 1rpm and applied pressure was 6 GPa. The structure of commercially pure magnesium prepared by casting and moulding were observed with focus on differences caused by input material. The structure was observed by both light microscopy and back scattered electron diffraction (EBSD), focusing on structure development, grain size and grain orientation. Compared to other works on similar topic, the emphasis here is on observing the microhardness on the vertical edge of the sample. The hardness shows a steep increase right after 1/8 of a turn. With increasing number of turns gradual homogenization of microhardness is presented accompanied by slight decrease in microhardness. No trend in microhardness relative to the distance from anvil has occurred. Structure observed with EBSD shows a bimodal character with larger grains oriented in the same direction. The three-point bending test didn’t end up as expected, and the approach to evaluation of magnesium-based HPT needs to be re-evaluated for future work. A three-point bending test was designed for the initial assessment of the basic mechanical properties of the material.

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See also: similar author names
3 NĚMEC, Karel
2 Němec, Kamil
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