|
| |
|
|
Experimental data processing for calibration of isotropic hardening model
Chlaň, Jakub ; Kubík, Petr (referee) ; Šebek, František (advisor)
The main aim of the present bachelor's thesis is to create a universally applicable script, which is used for the data processing of the fatigue test in order to calibrate the isotropic hardening model. The theoretical part is devoted to the phenomenon of cyclic hardening/softening, the mathematical models of hardening and last but not least, the practice of fatigue tests together with the possibilities of their evaluation. The rest of the work includes the algorithm creation procedure and demonstration of its functionality by processing data from fatigue tests of alloy AlCu4Mg1.
|
|
|
Measuring magnetic properties of environmental samples
Zárubová, Alžběta ; Petrovský, Eduard (advisor) ; Kapička, Aleš (referee)
A. Zárubová: Měření magnetických vlastností environmentálních vzorků 1 ENGLISH ABSTRACT This bachelor's thesis presents briefly principles and examples of applications of magnetic measurements in environmental studies. Environmental magnetism is based on determination of iron oxides, their content, concentration and grain size. This information can be interpreted in terms of particle origin, transport or diagenesis. The results can provide information on, e.g., climatic changes in the past, short-term events influencing our environment (e.g., volcanic eruptions) or about contemporary problems associated with human activity (environmental pollution). In the last case, environmental magnetism does not intend to replace geochemical methods, but the main aim is to provide fast and easily available additional information, which helps us to be more effective in mapping contaminated areas, monitoring progression of pollution or modeling transport processes of contaminants. Magnetometry is currently intensively used for mapping contamination of atmosphere, soils and sediments; it can be used in defining long-term levels of contamination, individual pollution sources and their contribution to the overall pollution. This thesis provides a brief overview of the physical basics of environmental magnetism and examples...
|
|
|
Low cycle fatigue of pseudoelastic NiTi alloy
Kaňová, Monika ; Hutař, Pavel (referee) ; Pantělejev, Libor (advisor)
This work is focused on study of mechanical properties of NiTi alloy which shows pseudoelastic and shape memory behaviour. Functional and structural fatigue of the material is examined. The main aim of this work was to perform and to evaluate a series of fatigue tests. The material was supplied in the form of wire which was gripped in the machine using special grips. In the first part of the experiment, tensile tests are evaluated and the reproducibility of measurements is demonstrated. Then, a series of cyclic tests was performed. Results were analysed together with previous measurements. One part of discussion concerned changes of the hysteresis loops during cycling and their dependence on strain rate. The fatigue life curves were plotted. It was found that these curves have non-standard shapes. The reasons for this are explained in the work.
|
|
|
Assesment of stress strain response during cyclic loading
Lehnert, Ondřej ; Slámečka, Karel (referee) ; Horníková, Jana (advisor)
This bachelor´s thesis is focused on assessment of data extracted from testing machine and establishment of cyclic stress-strain curve using peaks of saturated hysteresis loops. In this thesis before data analysis itself, is written down research study about general fatigue of material, then the study is focused on change of mechanical attributes, description of hysteresis loops and cyclic curve. After that follows the procedure of data analysis extracted from testing machine aimed to compare cyclic curve with tensile curve and its mathematical description.
|
|
| |
guest ::
