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Mechanical properties of magnesium alloy AZ91E prepared by ECAP method
Darida, Jiří ; Válka, Libor (referee) ; Pantělejev, Libor (advisor)
This thesis deals with mechanical and fatigue properties of magnesium alloy AZ91 processed by EX-ECAP method. This method involves the application of extrusion followed by equal-channel angular pressing. To obtain basic mechanical characteristics, the tensile test were carried out at room and elevated temperatures. Further the fatigue tests were performed and obtained data were used to compile S-N curve. The work also includes metallographics analysis of microstructure and fractographic analysis of fracture surfaces of tensile and fatigue test specimens.
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Zn and Mg based bulk materials for biomedical applications
Ryšťák, Jaroslav ; Fintová, Stanislava (referee) ; Doležal, Pavel (advisor)
Topic of the diploma thesis is Zn-Mg bulk material preparation by powder mixtures sintering at hot pressing. Structure, porosity and physically mechanical properties of prepared bulk materials were evaluated. Obtained results and their interpretation were served as feedback for following optimization of individual processing parameters of bulk materials preparation. Solution of diploma thesis is focused on study and control of processes during bulk material preparation and processes description from physical-chemical point of view with respect to structure creation and final material properties.
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Nanocomposites with a metal matrix
Chlupová, Monika ; Kohout, Jan (referee) ; Zapletal, Josef (advisor)
This baechelor thesis is focused on metal matrix nanocomposites (MMNCs), whose research has started recently. In the first part of this thesis are generally defined composite materials, the larger part is dedicated to metal matrix composites (MMCs), on which are described the strengthening mechanisms that are also applied to MMNCs. The second part of the thesis is focused specifically on MMNCs. The concept of MMNCs and their distribution is defined first, followed by a definition of the reinforcement that can be used for the production of MMNCs. There are also described the posibilities for the production of these reinforcing phases, and their influence on the structural and mechanical properties of the final MMNCs. This section is followed by a description of possible processes of MMNCs production with their advantages and limitations. The last part outlines how research and development of these materials should be carried out in order to be commercially produced and used in the future.
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The significance of magnesium for human health
Škeřík, Jan ; Hrstka, Miroslav (referee) ; Vránová, Dana (advisor)
Aim of this bachelor thesis was to compare different forms of magnesium. The characteristics and history of magnesium was briefly described at the beginning of the theoretical part. The following chapters explain the importance of magnesium in the body, hypomagnesemia, hypermagnesemia. Another section describes magnesium effect on various diseases, increased intake of magnesium and magnesium metabolism. The ninth and tenth chapter describes the effects of nicotine and alcohol on the metabolism of magnesium and magnesium content in drinking and mineral water. Conclusion of the theoretical part is dedicated to the description of the analytical methods of dosage forms. At the heart of the practical part was using several commonly used methods to determine best magnesium addition. It was the method of determination of the mass uniformity, determining magnesium contents in the tablet, the determination of disintegration, dissolution determination and hardness determination.
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Materials for biodegradable bones based on Fe
Hrabovský, Jan ; Vondrák, Jiří (referee) ; Sedlaříková, Marie (advisor)
The thesis deals with biodegradable bone implants which must have good mechanical properties and also good compatibility with the human body. The thesis contains literary research in the area of bone physiology, biogenic materials and implants for the human body. The thesis focues on the selection of suitable materials for biogenic implants. It is also described the preparation of iron powder mixtures and application onto selected materials. The selected samples were subjected to thermal analysis.
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Preparation and Characterization of Porous Magnesium Based Materials
Březina, Matěj ; Pacal, Bohumil (referee) ; Vojtěch, Dalibor (referee) ; Ptáček, Petr (advisor)
Bulk magnesium materials produced nowadays via powder metallurgy are based on a vastly extensive technological spectrum, which makes it possible to create a wide range of materials. This work focuses on the preparation of bulk materials from magnesium powder by cold pressing and hot pressing, sintering and field assisted sintering. The bulk materials were prepared in a series of compacting pressures from 100 MPa to 500 MPa and the sintering temperatures were selected in the range of 300 ° C to 600 ° C in order to characterize the influence of the manufacturing conditions and technology on the final properties of bulk materials. Prepared materials were evaluated in terms of microstructure, hardness, microhardness, three-point bend test, and fractography. From the hot pressed materials, the samples prepared at 400 and 500 MPa and 400 °C had the highest strength and hardness. The classic sintering of magnesium in the furnace with argon atmosphere proved to be ineffective due to the oxide layer on the surface and the presence of oxygen in technical argon. The SPS sintering (Spark Plasma Sintering) was the more effective with the lower applying pressure used to make the preforms and with the higher applied pressure during the SPS process itself. Highest strength and hardness were achieved in this case of materials sintered at 600 ° C prepared from free powder and the most porous preform (100 MPa). The bulk materials were prepared using all methods used, but the properties of these materials varied considerably depending on the technology used.
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Biocompatible metallic materials
Mišáková, Liliana ; Věchet, Stanislav (referee) ; Němec, Karel (advisor)
This bachelor´s thesis, which was processed in the form of literary research, deals with the issue of biocompatible metallic materials. The aim of this work is to provide an overview of the materials used in general medicine and dentistry and to present the latest knowledge of their development. The first part is devoted to the characterization of biomaterials and their division. In the next section, metals and their alloys are listed together with their desired properties and typical applications. The following section focuses on the method of surface treatment of titanium, which enables it to achieve better bioactivity. The final part of this thesis offers the latest findings on the properties and the way of using low-melting-point alloys.
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Corrosion of biodegradable magnesium alloys in Hank's solutions
Faltejsek, Petr ; Fintová, Stanislava (referee) ; Doležal, Pavel (advisor)
The aim of the thesis was to design a methodology for in-situ evaluation of degradation of selected magnesium alloys using AFM in SBF solutions. Study of the degradation of magnesium alloys in a chemically different corrosive environments of simulated body fluid (SBF - Hank's solution). For the pilot study were used magnesium alloys AZ31 and AZ61, manufactured by advanced method of squeeze casting. Part of the thesis was to evaluate the influence of the chemical composition and structure on the degradation properties of these alloys.
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