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Modification of electroinsulating varnish with ground mica
Drápal, Aleš ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This master's thesis focuses on composite systems based on varnish combined with different filler ratios of micronized mica. The aim is to analyse impact of the filler on dielectric properties of the varnish, i.e. relative permittivity and loss factor as functions of frequency as well as charging and discharging currents as functions of time. Dielectric mixture formulas are applied on relative permittivity values. Calculated and measured values are compared.
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Impact of the climatic conditions upon the varnishes properties
Mikoláš, Jiří ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This bachelor's project analysis influence of moisture absorption on dielectric properties of composite material, which was exposured various relative humidity. The composite material consist of epoxide varnish EPOXYLITE TSA 220S by company Epoxylite Ltd. with various weight percentage number micro-ground mica. This experiment was carried out by dielectric relaxation spectroscopy with frequency range from 100 Hz to 1 MHz. Elementary results of this project are composite material frequency dependencies of component part of complex permittivity.
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Utilization of mica separated from washed kaolin
Vaculík, Josef ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
The Master’s Thesis aims to laboratory test the possibilities of utilization mica separate, which arises during the process of floating kaolin as a by-product together with sand. Mica and sand are then separated by flotation or vibration. The mica separate thus formed was subjected to analysis. XRD and heating microscopy methods were used for analysis. Subsequently, experiments with mica separation as a filler in composites based on epoxy resins were set up and performed. Furthermore, the separate was tested as a part of plasters and visual building elements. Last but not least, the separate was mixed into the ceramic, which was then subjected to firing in the selected mode. The diploma thesis provides a comprehensive overview of the above-mentioned possibilities of using mica separation, which is based on a sufficient amount of experimental data.
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Study of electric properties of composite
Bariš, Marián ; Havlíček, Svatopluk (referee) ; Polsterová, Helena (advisor)
The theme of this Bachelor's thesis is a problematics of composite materials. On a given samples of polyamide with a various weight filling of a milled mica were measured resistivity, permittivity and loss factor on a consequence of a temperature and filling. The chosen type was a filling with a milled mica in range from 0 to 40 of a weight percentage, temperatures were in range from 20 °C to 90 °C.
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Analysis of varnish composites properties in the course of moisture
Novák, Petr ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
The presented bachelor´s work deals with preparation of micronized mica filled varnish sauples. At the same time the temperature and relative humidity influence on the electrical properties of composite material by dielectric relaxation spectroscopy method are monitoring. The composite material consists of epoxide varnish TSA 220S, which is modified with different mass percentage of micronized mica. The results of this project are frequency dependencies of real and imaginary parts of complex permitivity with the environmental temperatures and humidities parameters of varnish components.
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Dielectric absorption of varnish composites
Reňák, Ladislav ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This work deals with issues of electro insulating varnishes and composite materiále within the frame of dielectric changes depending on a change of relative humidity where these varnishes are located. For this purpose had been created variety of a samples of electroinsulating varnish with different percentage of filling with mica. The general aim is acquire information about dielectric changes of examined electro insulating varnishes that are exposed to atmospheric influence.
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Study of electric properties of composite
Bariš, Marián ; Havlíček, Svatopluk (referee) ; Polsterová, Helena (advisor)
The theme of this Bachelor's thesis is a problematics of composite materials. On a given samples of polyamide with a various weight filling of a milled mica were measured resistivity, permittivity and loss factor on a consequence of a temperature and filling. The chosen type was a filling with a milled mica in range from 0 to 40 of a weight percentage, temperatures were in range from 20 °C to 90 °C.
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Influence of the Temperature on the Dielectric properties epoxy with ground mica
Ráček, Tomáš ; Havlíček, Svatopluk (referee) ; Polsterová, Helena (advisor)
The paper is focused on theoretical analysis of the basic characteristics of dielectrics, especially on the examination of these qualities at samples of epoxy sealing compound filled with powder mica, and their dependance on the temperature and the content of filling in the material. The measured quantities are inner resistivity, relative permitivity, and loss factor. The paper also deals with the sensitivity of the material to humidity, and through the influence of humidity to the other measured quantities.
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Behaviour of varnish composite in various environmental condtions
Kadlec, Michal ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
The diploma thesis is focused on the preparation of test samples of paint-filled micronized mica and analysis of electrical properties of insulating material values in different environmental conditions. For this purpose, it was created five sets of composite paint primers with different ratio of mica. Samples were gradually exposed to the environment relative humidity of 0%, 33%, 55%, 65% and 75%. For each environment with a defined moisture characteristics were observed in samples exposed to the temperature of 20 to 50 ° C. The diploma paper analyzed the influence of the mass implementation of mica in each set of samples and placed on the surface structure of samples.
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